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• 371. [Article] Life history and environmental influences on avian incubation and parental care in songbirds

  Patterns of nest attendance behavior by breeding birds represent a parent-offspring trade-off in which adults balance self-maintenance with parental care decisions. Incubation, in particular, is of interest ...

  Citation × Citation Citation Abstract Copy Title: Life history and environmental influences on avian incubation and parental care in songbirds Author: Austin-Bythell, Suzanne H. Patterns of nest attendance behavior by breeding birds represent a parent-offspring trade-off in which adults balance self-maintenance with parental care decisions. Incubation, in particular, is of interest because adults must provide an environment suitable for embryonic development through nest-building and contact-incubation. We evaluated how adult incubation constancy and nest visitation rates varied with life and natural history traits of temperate and tropical bird species. We found that constancy did not differ by latitude or with nest survival rate. A strong negative correlation between incubation constancy and egg mass relative to adult body mass was present. Birds with low constancy tended to have larger relative egg masses and higher basal metabolic rate. Because adult incubation constancy is relatively plastic (i.e., varies with ambient temperature), birds with larger relative eggs may respond to lower cooling rates rather than direct selection for higher or lower constancy. We then assessed if rates of nest visitation (trips to nests by adults during incubation and nestling phases) followed the predictions of the Skutch hypothesis. Skutch suggested that birds nesting in environments with high levels of nest predation would reduce numbers of trips to their nests so as to minimize the risk of visual detection by nest predators. We found support for the basic pattern predicted by Skutch. We also extended his hypothesis to predict other behavior associated with nesting, such as responses of parents to intruders at the nest. Despite apparently early departure from the nest site, adults with higher visitation rates remained conspicuous around the nest site. Thus, while the flight initiation distance from the human observer was earlier than expected, conspicuousness of behavior was associated with nest visitation rate. Finally, we assessed how an environmental variable, photoperiod, might influence rate of embryonic development in a wild songbird, Sylvia atricapilla. We exposed eggs throughout the incubation period to daily photoperiods consisting of 4 hours of light and 20 hours of dark (4L), 12 hours light and 12 hours dark (12L), 20 hours light and 4 hours dark (20L) and a skeleton photoperiod with two 1-hour pulses of light that framed a 20-hour day. We found that the skeleton treatment group differed significantly from our 4L and 12L, but not the 20L treatment groups. The skeleton photoperiod accelerated embryonic development. We suggest that photoperiod may influence incubation period in wild birds and could account for some portion of the widely observed latitudinal variation in incubation period of songbirds. We encourage others to assess how photoperiod interacts with parental attendance patterns to affect embryonic development. Title: Life history and environmental influences on avian incubation and parental care in songbirds Author: Austin-Bythell, Suzanne H. Patterns of nest attendance behavior by breeding birds represent a parent-offspring trade-off in which adults balance self-maintenance with parental care decisions. Incubation, in particular, is of interest because adults must provide an environment suitable for embryonic development through nest-building and contact-incubation. We evaluated how adult incubation constancy and nest visitation rates varied with life and natural history traits of temperate and tropical bird species. We found that constancy did not differ by latitude or with nest survival rate. A strong negative correlation between incubation constancy and egg mass relative to adult body mass was present. Birds with low constancy tended to have larger relative egg masses and higher basal metabolic rate. Because adult incubation constancy is relatively plastic (i.e., varies with ambient temperature), birds with larger relative eggs may respond to lower cooling rates rather than direct selection for higher or lower constancy. We then assessed if rates of nest visitation (trips to nests by adults during incubation and nestling phases) followed the predictions of the Skutch hypothesis. Skutch suggested that birds nesting in environments with high levels of nest predation would reduce numbers of trips to their nests so as to minimize the risk of visual detection by nest predators. We found support for the basic pattern predicted by Skutch. We also extended his hypothesis to predict other behavior associated with nesting, such as responses of parents to intruders at the nest. Despite apparently early departure from the nest site, adults with higher visitation rates remained conspicuous around the nest site. Thus, while the flight initiation distance from the human observer was earlier than expected, conspicuousness of behavior was associated with nest visitation rate. Finally, we assessed how an environmental variable, photoperiod, might influence rate of embryonic development in a wild songbird, Sylvia atricapilla. We exposed eggs throughout the incubation period to daily photoperiods consisting of 4 hours of light and 20 hours of dark (4L), 12 hours light and 12 hours dark (12L), 20 hours light and 4 hours dark (20L) and a skeleton photoperiod with two 1-hour pulses of light that framed a 20-hour day. We found that the skeleton treatment group differed significantly from our 4L and 12L, but not the 20L treatment groups. The skeleton photoperiod accelerated embryonic development. We suggest that photoperiod may influence incubation period in wild birds and could account for some portion of the widely observed latitudinal variation in incubation period of songbirds. We encourage others to assess how photoperiod interacts with parental attendance patterns to affect embryonic development. Close

• 372. [Article] Biological Soil Crusts of the Great Basin : An Examination of their Distribution, Recovery from Disturbance and Restoration

  We are at risk of losing the sagebrush steppe in the floristic Great Basin to the invasion of Bromus tectorum L., cheatgrass. The floristic Great Basin includes the Central Basin and Range, the Northern ...

  Citation × Citation Citation Abstract Copy Title: Biological Soil Crusts of the Great Basin : An Examination of their Distribution, Recovery from Disturbance and Restoration Author: Condon, Lea A. We are at risk of losing the sagebrush steppe in the floristic Great Basin to the invasion of Bromus tectorum L., cheatgrass. The floristic Great Basin includes the Central Basin and Range, the Northern Basin and Range, and the Snake River Plain. The Great Basin receives most of its precipitation as winter snow and experiences hot and dry summers. Early accounts of invasion by cheatgrass associated it with farming and grazing practices. The non-farmed areas in the region are still actively grazed and referred to as rangelands. On invaded sites, cheatgrass changes the flammability of fuels on invaded landscapes, across the Great Basin, from coarser fuels that are widely spaced to fine fuels that are continuous, filling interspaces between perennial plants. The fuel load created by cheatgrass regenerates annually. This has resulted in a change in the fire regime of the Great Basin from infrequent, small fires to more frequent large fires. In arid lands globally, soil interspaces between perennial plants are typically filled by biological soil crusts (biocrusts). This is also true for ecoregions in and surrounding the Great Basin. Biocrusts are known to influence many ecosystem processes that cheatgrass influences, specifically nutrient cycling and availability of soil moisture. However, little work has been done on biocrusts of the Great Basin and to my knowledge, no one had restored biocrusts within the Great Basin. I attempt to fill some of this knowledge "interspace" by relating biocrust presence to disturbances and cheatgrass invasion and to demonstrate the potential for biocrust restoration within this region. Previous work in eastern Oregon demonstrated relationships between declines in biocrusts and increases in cheatgrass with increasing grazing intensity, soil temperature, and decreasing soil moisture. Grazing intensity influences the cover of biocrusts as well as the abundance and composition of native bunchgrasses. Native bunchgrasses influence the interspace gap size between perennial herbaceous vegetation which is directly associated with the cover of cheatgrass. In a region where grazing records may be incomplete and may exist in various forms of data, having a simple indicator of grazing impacts would be useful. It is also crucial that we have an understanding of what leads to loss of site resistance to cheatgrass. This previous work suggested that cover of biocrusts, in addition to bunchgrass composition, were associated with increased site resistance to cheatgrass. In Chapter 2, I used current grazing records from a range of suspected grazing intensities, to examine the ability of both biocrusts and perennial vegetation to maintain site resistance to cheatgrass after fire. I examined the ability of mosses and lichens to maintain site resistance separately given that these are two very different kinds of organisms. Mosses are non-vascular plants and early colonizers of sites in primary succession. Lichens have a symbiotic relationship between a fungus and a photosynthesizing partner, a cyanobacteria, an algae or both. Using structural equation models, I corroborated that perennial vegetation and lichens are associated with increased site resistance to cheatgrass and that mosses are associated with and may facilitate both lichens and perennial herbaceous vegetation. Also in Chapter 2, I identified that burned sites were associated with increased grazing pressure by livestock as shown by increases in cow dung density and increases in gap size between perennial herbaceous vegetation. The Great Basin is managed for cover of perennial vegetation but it could also be managed for morphogroups of biocrusts. Considering morphogroups of biocrusts, which were shown in the Chapter 2 to be important for site resilience and resistance, I wanted to determine if there were site characteristics associated with biocrust distribution and recovery from disturbance, across the Great Basin. Outside of the Great Basin on the Columbia Plateau, others had found that mosses were still present on disturbed sites whereas lichens were often lost. In addition, biocrust species were more associated with soil properties than with grazing by livestock. Given that grazing by livestock and fire are common disturbances across the region, I wanted to know if the same relationships between biocrusts, soil properties and disturbance were true in the Great Basin. I found that cover of the lichen component of biocrusts was higher on sites that were both ungrazed and unburned. Factors related to disturbance characteristics were correlated with the recovery of biocrusts, even after accounting for time since fire. Factors related to disturbance, a composite of grazing and fire, were more important for structuring the cover and composition of morphogroups as opposed to environmental conditions. Lichens were the most sensitive morphogroup, compared to tall mosses, followed by short mosses which were favored by some disturbance but reduced in cover immediately after fire. Perennial grasses were also favored by some disturbance and perennial forbs did not show an obvious relationship with a disturbance gradient. Chapter 3 highlights that grazing by livestock and fire are common disturbances across the region so much so that the effects of one on the abundances of morphogroups could not be separated from the other. Given the observed contributions of biocrusts to site resilience and resistance, I wanted to know if we could restore biocrusts in the field. Others have grown mosses in a lab setting but this was the first study to restore mosses in the Great Basin. I tested the influence of factors that are commonly used in the field of restoration for facilitating plant establishment. I tested the influence of season of inoculation (fall versus spring), the addition of organic matter (in the form of jute net), irrigation (in the spring season) and the climatic setting of moss the collection sites (for moss propagation), in comparison to the experiment site (warm, dry versus cool, moist) on moss growth. I used two moss species: a ruderal (Bryum argenteum) and a later successional species (Syntrichia ruralis). Moss cover increased when the climatic setting of the collection site matched the experiment site. Mosses were facilitated by the addition of the organic jute netting, putting on most of their growth in winter. Although there is still a great deal of work to be done developing moss material for restoration and working out inoculation rates of moss fragments, similar to seeding rates, land managers have another tool to consider when rehabilitating sites after disturbance. Managing the Great Basin for biocrusts in the presence of grazing and fire will not only increase site resistance to cheatgrass but it will add to the conservation of ecosystem functions related to nutrient cycling, hydrologic cycling and soil erosion. Site resistance will be improved with increased periods of rest from grazing following fire. The lichen component of biocrusts is a more sensitive indicator of disturbance when compared with mosses or perennial vegetation but we are currently actively managing for perennial vegetation and not biocrusts. The moss component of biocrusts can be successfully restored in the Great Basin, without irrigation. This dissertation shows that land managers should consider a suite of organisms, in addition to perennial plants to achieve management goals and maintain site resistance to cheatgrass. Title: Biological Soil Crusts of the Great Basin : An Examination of their Distribution, Recovery from Disturbance and Restoration Author: Condon, Lea A. We are at risk of losing the sagebrush steppe in the floristic Great Basin to the invasion of Bromus tectorum L., cheatgrass. The floristic Great Basin includes the Central Basin and Range, the Northern Basin and Range, and the Snake River Plain. The Great Basin receives most of its precipitation as winter snow and experiences hot and dry summers. Early accounts of invasion by cheatgrass associated it with farming and grazing practices. The non-farmed areas in the region are still actively grazed and referred to as rangelands. On invaded sites, cheatgrass changes the flammability of fuels on invaded landscapes, across the Great Basin, from coarser fuels that are widely spaced to fine fuels that are continuous, filling interspaces between perennial plants. The fuel load created by cheatgrass regenerates annually. This has resulted in a change in the fire regime of the Great Basin from infrequent, small fires to more frequent large fires. In arid lands globally, soil interspaces between perennial plants are typically filled by biological soil crusts (biocrusts). This is also true for ecoregions in and surrounding the Great Basin. Biocrusts are known to influence many ecosystem processes that cheatgrass influences, specifically nutrient cycling and availability of soil moisture. However, little work has been done on biocrusts of the Great Basin and to my knowledge, no one had restored biocrusts within the Great Basin. I attempt to fill some of this knowledge "interspace" by relating biocrust presence to disturbances and cheatgrass invasion and to demonstrate the potential for biocrust restoration within this region. Previous work in eastern Oregon demonstrated relationships between declines in biocrusts and increases in cheatgrass with increasing grazing intensity, soil temperature, and decreasing soil moisture. Grazing intensity influences the cover of biocrusts as well as the abundance and composition of native bunchgrasses. Native bunchgrasses influence the interspace gap size between perennial herbaceous vegetation which is directly associated with the cover of cheatgrass. In a region where grazing records may be incomplete and may exist in various forms of data, having a simple indicator of grazing impacts would be useful. It is also crucial that we have an understanding of what leads to loss of site resistance to cheatgrass. This previous work suggested that cover of biocrusts, in addition to bunchgrass composition, were associated with increased site resistance to cheatgrass. In Chapter 2, I used current grazing records from a range of suspected grazing intensities, to examine the ability of both biocrusts and perennial vegetation to maintain site resistance to cheatgrass after fire. I examined the ability of mosses and lichens to maintain site resistance separately given that these are two very different kinds of organisms. Mosses are non-vascular plants and early colonizers of sites in primary succession. Lichens have a symbiotic relationship between a fungus and a photosynthesizing partner, a cyanobacteria, an algae or both. Using structural equation models, I corroborated that perennial vegetation and lichens are associated with increased site resistance to cheatgrass and that mosses are associated with and may facilitate both lichens and perennial herbaceous vegetation. Also in Chapter 2, I identified that burned sites were associated with increased grazing pressure by livestock as shown by increases in cow dung density and increases in gap size between perennial herbaceous vegetation. The Great Basin is managed for cover of perennial vegetation but it could also be managed for morphogroups of biocrusts. Considering morphogroups of biocrusts, which were shown in the Chapter 2 to be important for site resilience and resistance, I wanted to determine if there were site characteristics associated with biocrust distribution and recovery from disturbance, across the Great Basin. Outside of the Great Basin on the Columbia Plateau, others had found that mosses were still present on disturbed sites whereas lichens were often lost. In addition, biocrust species were more associated with soil properties than with grazing by livestock. Given that grazing by livestock and fire are common disturbances across the region, I wanted to know if the same relationships between biocrusts, soil properties and disturbance were true in the Great Basin. I found that cover of the lichen component of biocrusts was higher on sites that were both ungrazed and unburned. Factors related to disturbance characteristics were correlated with the recovery of biocrusts, even after accounting for time since fire. Factors related to disturbance, a composite of grazing and fire, were more important for structuring the cover and composition of morphogroups as opposed to environmental conditions. Lichens were the most sensitive morphogroup, compared to tall mosses, followed by short mosses which were favored by some disturbance but reduced in cover immediately after fire. Perennial grasses were also favored by some disturbance and perennial forbs did not show an obvious relationship with a disturbance gradient. Chapter 3 highlights that grazing by livestock and fire are common disturbances across the region so much so that the effects of one on the abundances of morphogroups could not be separated from the other. Given the observed contributions of biocrusts to site resilience and resistance, I wanted to know if we could restore biocrusts in the field. Others have grown mosses in a lab setting but this was the first study to restore mosses in the Great Basin. I tested the influence of factors that are commonly used in the field of restoration for facilitating plant establishment. I tested the influence of season of inoculation (fall versus spring), the addition of organic matter (in the form of jute net), irrigation (in the spring season) and the climatic setting of moss the collection sites (for moss propagation), in comparison to the experiment site (warm, dry versus cool, moist) on moss growth. I used two moss species: a ruderal (Bryum argenteum) and a later successional species (Syntrichia ruralis). Moss cover increased when the climatic setting of the collection site matched the experiment site. Mosses were facilitated by the addition of the organic jute netting, putting on most of their growth in winter. Although there is still a great deal of work to be done developing moss material for restoration and working out inoculation rates of moss fragments, similar to seeding rates, land managers have another tool to consider when rehabilitating sites after disturbance. Managing the Great Basin for biocrusts in the presence of grazing and fire will not only increase site resistance to cheatgrass but it will add to the conservation of ecosystem functions related to nutrient cycling, hydrologic cycling and soil erosion. Site resistance will be improved with increased periods of rest from grazing following fire. The lichen component of biocrusts is a more sensitive indicator of disturbance when compared with mosses or perennial vegetation but we are currently actively managing for perennial vegetation and not biocrusts. The moss component of biocrusts can be successfully restored in the Great Basin, without irrigation. This dissertation shows that land managers should consider a suite of organisms, in addition to perennial plants to achieve management goals and maintain site resistance to cheatgrass. Close

• 373. [Article] Hood River Bull Trout Abundance, Life History, and Habitat Connectivity, 2007 Progress Reports 2007

  Abstract -- Hood River bull trout are thought to exist as two independent reproductive units (USFWS 2004), known as local populations (Rieman and McIntyre 1995). The Clear Branch local population is isolated ...

  Citation × Citation Citation Abstract Copy Title: Hood River Bull Trout Abundance, Life History, and Habitat Connectivity, 2007 Progress Reports 2007 Abstract -- Hood River bull trout are thought to exist as two independent reproductive units (USFWS 2004), known as local populations (Rieman and McIntyre 1995). The Clear Branch local population is isolated above Clear Branch Dam, which provides limited downstream fish passage during infrequent and sporadic periods of spill and no upstream passage. Bull trout in this population inhabit Laurance Lake Reservoir and tributaries upstream of Clear Branch Dam. The Hood River local population occurs in the mainstem Hood River and Middle Fork Hood River downstream of the Clear Branch Dam and a small number of adult bull trout migrate each year into the Hood River from the Columbia River (Figure 1). The status of both populations is extremely precarious. The Clear Branch population is at risk of a random extinction event due to low numbers, negative interactions with non-native smallmouth bass, isolation and limited spawning habitat (USFWS, 1998). The Hood River population also appears to be small and is threatened by passage barriers, unscreened irrigation systems, impaired water quality and periodic siltation of spawning substrate by glacial outbursts. Clear Branch bull trout spawn in Clear Branch and Pinnacle Creek. After rearing in these two natal streams for an unknown time period, most are believed to migrate downstream to Laurance Lake Reservoir. Clear Branch bull trout have been documented passing over the dam spillway during high water events (Pribyl et al. 1996) and may provide a recruitment source for the Hood River local population. Adult bull trout tagged at Powerdale Dam have been observed at Coe Branch irrigation diversion and in a trap at the base of Clear Branch dam. These fish may have been attempting to reach spawning areas located upstream of the dam. However, the success of bull trout migrating downstream via the spillway or the possibility of successfully navigating through the diversion network has never been determined. Depending on the water year, the Middle Fork Irrigation District (MFID) may not spill at all, or the timing of the spill may not coincide with the timing of downstream migration, which is currently unknown (East Fork Hood River and Middle Fork Hood River Watershed analysis). Smallmouth bass were discovered in Lake Laurance Reservoir in the 1990s. Creel surveys have shown that large adult bass are caught occasionally in the reservoir and schools of bass fry have been seen by district fish biologist (Rod French, ODFW, personal communication), suggesting that they are spawning successfully. This illegal introduction poses a potential threat to the Clear Branch bull trout population, but its magnitude is unknown because the bass population size and degree of interaction between the two species are unknown. Bull trout and smallmouth bass have significantly different temperature preferences and tolerances, with bull trout being one of the most sensitive coldwater species and bass being a warm water species. Lake Laurance, a relatively high-altitude reservoir at 890 m (2,920 feet), does not provide ideal bass habitat so these two species may have largely non-overlapping distributions or differing activity periods (Terry Shrader, ODFW warmwater fish biologist, personal communication). However, based on past reservoir temperature data (Berger et al. 2005), there are periods in the reservoir when there is potential for bull trout and bass interaction: periods when bull trout are susceptible to bass predation and when juvenile fish might compete for resources. Spawning activity of the Hood River local population has been observed in a few locations within the Middle Fork of Hood River (Figure 1). Although consistent and extensive spawning areas for this population are not known, some of the locations where juvenile rearing or potential bull trout redds have been observed include the Middle Fork Hood River and some of its tributaries: Bear Creek, Compass Creek and Coe Branch (USFWS 2004). However, Coe Branch, Compass Creek, and the Middle Fork are glacial streams with a high volume of sand and silt which may compromise spawning success. No bull trout spawning or rearing has been observed on the East and West Forks of Hood River. The Middle Fork and mainstem Hood River provide foraging, migration and overwintering habitat. Hood River bull trout are also known to migrate into the Columbia River. Two bull trout tagged at Powerdale Dam (RK 7.2 of mainstem Hood River) were recovered near Drano Lake in Washington State; and one was captured 11 kilometers downstream of the confluence of the Hood and Columbia Rivers (USFWS 2004). Every year (usually between May and July), adult bull trout, presumably migrating upstream from the Columbia River, are captured and anchor tagged at Powerdale Dam. Although some of these tagged fish have been observed upstream (one in Coe Branch and three below Clear Branch dam), the spawning destination of fluvial adults within the Hood River basin is largely unknown. Dispersing juvenile bull trout and migrating adults in this local population are threatened by flow diversions with inadequate screening and passage facilities. Several structures are suspected to impede upstream migration or entrain juvenile and adult bull trout into irrigation works (Pribyl et al. 1996, HRWG 1999). These structures include: the diversion at Clear Branch Dam (passage and screening), Coe Branch (passage and screening), and the Farmers Irrigation District diversion (screening) on the mainstem Hood River (HRWG 1999). However, little research has been conducted to assess the impacts of these structures on migrating bull trout. Beyond a general knowledge of the distribution of Hood River bull trout and the nature of anthropogenic factors that potentially restrict their life history and habitat connectivity, little is known about this recovery unit. Baseline information about adult abundance is lacking for both local populations, the potential of a source (Clear Branch) and sink (Hood River) relationship between the two local populations has not been explored, and the migratory life history of adult fish caught at Powerdale Dam is unknown. The degree to which irrigation and hydropower diversions hamper connectivity within the Hood River basin is also poorly understood. Migratory life histories have been viewed as key to species persistence (Rieman and McIntyre 1995; Dunham and Rieman 1999), and understanding movement patterns and associated habitat requirements are critical to maintaining those migratory forms (Muhlfeld and Morotz 2005; Hostettler 2005). Gaining this information is also critical to evaluating bull trout recovery in the Hood River Subbasin (Coccoli 2004). The Oregon Department of Fish and Wildlife (ODFW) initiated a study in 2006 to improve our understanding of the abundance, life history, and potential limiting factors of the bull trout in this recovery unit. This report describes findings for the first two years of the study (2006-2007). Specific study objectives for the first two years were: 1. Determine the migratory life history of Hood River bull trout and assess the potential impacts of flow diversions and two new falls on the Middle Fork Hood River (scoured by the November 2006 glacial outburst) on bull trout migrations. 2. Determine current distribution of bull trout reproduction and early rearing in historical and potential bull trout streams in the Hood River Subbasin. 3. Determine the juvenile and adult life history the Clear Branch local population and develop a statistically reliable and cost-effective protocol for monitoring the abundance of adult Clear Branch bull trout. 4. Assess the potential impact of smallmouth bass on bull trout in Laurance Lake Reservoir. Title: Hood River Bull Trout Abundance, Life History, and Habitat Connectivity, 2007 Progress Reports 2007 Abstract -- Hood River bull trout are thought to exist as two independent reproductive units (USFWS 2004), known as local populations (Rieman and McIntyre 1995). The Clear Branch local population is isolated above Clear Branch Dam, which provides limited downstream fish passage during infrequent and sporadic periods of spill and no upstream passage. Bull trout in this population inhabit Laurance Lake Reservoir and tributaries upstream of Clear Branch Dam. The Hood River local population occurs in the mainstem Hood River and Middle Fork Hood River downstream of the Clear Branch Dam and a small number of adult bull trout migrate each year into the Hood River from the Columbia River (Figure 1). The status of both populations is extremely precarious. The Clear Branch population is at risk of a random extinction event due to low numbers, negative interactions with non-native smallmouth bass, isolation and limited spawning habitat (USFWS, 1998). The Hood River population also appears to be small and is threatened by passage barriers, unscreened irrigation systems, impaired water quality and periodic siltation of spawning substrate by glacial outbursts. Clear Branch bull trout spawn in Clear Branch and Pinnacle Creek. After rearing in these two natal streams for an unknown time period, most are believed to migrate downstream to Laurance Lake Reservoir. Clear Branch bull trout have been documented passing over the dam spillway during high water events (Pribyl et al. 1996) and may provide a recruitment source for the Hood River local population. Adult bull trout tagged at Powerdale Dam have been observed at Coe Branch irrigation diversion and in a trap at the base of Clear Branch dam. These fish may have been attempting to reach spawning areas located upstream of the dam. However, the success of bull trout migrating downstream via the spillway or the possibility of successfully navigating through the diversion network has never been determined. Depending on the water year, the Middle Fork Irrigation District (MFID) may not spill at all, or the timing of the spill may not coincide with the timing of downstream migration, which is currently unknown (East Fork Hood River and Middle Fork Hood River Watershed analysis). Smallmouth bass were discovered in Lake Laurance Reservoir in the 1990s. Creel surveys have shown that large adult bass are caught occasionally in the reservoir and schools of bass fry have been seen by district fish biologist (Rod French, ODFW, personal communication), suggesting that they are spawning successfully. This illegal introduction poses a potential threat to the Clear Branch bull trout population, but its magnitude is unknown because the bass population size and degree of interaction between the two species are unknown. Bull trout and smallmouth bass have significantly different temperature preferences and tolerances, with bull trout being one of the most sensitive coldwater species and bass being a warm water species. Lake Laurance, a relatively high-altitude reservoir at 890 m (2,920 feet), does not provide ideal bass habitat so these two species may have largely non-overlapping distributions or differing activity periods (Terry Shrader, ODFW warmwater fish biologist, personal communication). However, based on past reservoir temperature data (Berger et al. 2005), there are periods in the reservoir when there is potential for bull trout and bass interaction: periods when bull trout are susceptible to bass predation and when juvenile fish might compete for resources. Spawning activity of the Hood River local population has been observed in a few locations within the Middle Fork of Hood River (Figure 1). Although consistent and extensive spawning areas for this population are not known, some of the locations where juvenile rearing or potential bull trout redds have been observed include the Middle Fork Hood River and some of its tributaries: Bear Creek, Compass Creek and Coe Branch (USFWS 2004). However, Coe Branch, Compass Creek, and the Middle Fork are glacial streams with a high volume of sand and silt which may compromise spawning success. No bull trout spawning or rearing has been observed on the East and West Forks of Hood River. The Middle Fork and mainstem Hood River provide foraging, migration and overwintering habitat. Hood River bull trout are also known to migrate into the Columbia River. Two bull trout tagged at Powerdale Dam (RK 7.2 of mainstem Hood River) were recovered near Drano Lake in Washington State; and one was captured 11 kilometers downstream of the confluence of the Hood and Columbia Rivers (USFWS 2004). Every year (usually between May and July), adult bull trout, presumably migrating upstream from the Columbia River, are captured and anchor tagged at Powerdale Dam. Although some of these tagged fish have been observed upstream (one in Coe Branch and three below Clear Branch dam), the spawning destination of fluvial adults within the Hood River basin is largely unknown. Dispersing juvenile bull trout and migrating adults in this local population are threatened by flow diversions with inadequate screening and passage facilities. Several structures are suspected to impede upstream migration or entrain juvenile and adult bull trout into irrigation works (Pribyl et al. 1996, HRWG 1999). These structures include: the diversion at Clear Branch Dam (passage and screening), Coe Branch (passage and screening), and the Farmers Irrigation District diversion (screening) on the mainstem Hood River (HRWG 1999). However, little research has been conducted to assess the impacts of these structures on migrating bull trout. Beyond a general knowledge of the distribution of Hood River bull trout and the nature of anthropogenic factors that potentially restrict their life history and habitat connectivity, little is known about this recovery unit. Baseline information about adult abundance is lacking for both local populations, the potential of a source (Clear Branch) and sink (Hood River) relationship between the two local populations has not been explored, and the migratory life history of adult fish caught at Powerdale Dam is unknown. The degree to which irrigation and hydropower diversions hamper connectivity within the Hood River basin is also poorly understood. Migratory life histories have been viewed as key to species persistence (Rieman and McIntyre 1995; Dunham and Rieman 1999), and understanding movement patterns and associated habitat requirements are critical to maintaining those migratory forms (Muhlfeld and Morotz 2005; Hostettler 2005). Gaining this information is also critical to evaluating bull trout recovery in the Hood River Subbasin (Coccoli 2004). The Oregon Department of Fish and Wildlife (ODFW) initiated a study in 2006 to improve our understanding of the abundance, life history, and potential limiting factors of the bull trout in this recovery unit. This report describes findings for the first two years of the study (2006-2007). Specific study objectives for the first two years were: 1. Determine the migratory life history of Hood River bull trout and assess the potential impacts of flow diversions and two new falls on the Middle Fork Hood River (scoured by the November 2006 glacial outburst) on bull trout migrations. 2. Determine current distribution of bull trout reproduction and early rearing in historical and potential bull trout streams in the Hood River Subbasin. 3. Determine the juvenile and adult life history the Clear Branch local population and develop a statistically reliable and cost-effective protocol for monitoring the abundance of adult Clear Branch bull trout. 4. Assess the potential impact of smallmouth bass on bull trout in Laurance Lake Reservoir. Close

• 374. [Article] All in a DNA's work : conservation genetics and monitoring of the New Zealand endemic Maui's and Hector's dolphins

  The critically endangered Maui's dolphin (Cephalorhynchus hectori maui) and the endangered Hector's dolphin (C. h. hectori) are endemic to the coastal waters of New Zealand, where their primary threat ...

  Citation × Citation Citation Abstract Copy Title: All in a DNA's work : conservation genetics and monitoring of the New Zealand endemic Maui's and Hector's dolphins Author: Hamner, Rebecca Marie The critically endangered Maui's dolphin (Cephalorhynchus hectori maui) and the endangered Hector's dolphin (C. h. hectori) are endemic to the coastal waters of New Zealand, where their primary threat is fisheries-related mortality. The Maui's dolphin is among the most critically endangered cetaceans in the world, with its remnant population primarily concentrated in approximately 140 km along the central west coast of New Zealand's North Island. Its closely related sister subspecies, the Hector's dolphin, is more abundant and offers a useful comparison for studying the Maui's dolphin. My work used genetic tools to examine demographic and genetic parameters relevant for conservation considerations regarding Maui's and Hector's dolphins, as well as to build upon past genetic baselines for the purpose of long-term genetic monitoring of these subspecies. Three genetic datasets formed the basis for most analyses: (1) Maui's 01-07, including 54 Maui's dolphin individuals sampled between 2001 and 2007 (n = 70 biopsies, 12 beachcast); (2) Maui's 10-11, including 40 Maui's dolphin individuals sampled in 2010 and 2011 (n = 69 biopsies, 1 beachcast); and (3) Hector's CB11-12, including 148 Hector's dolphin individuals sampled in Cloudy Bay in 2011 and 2012 (n = 263 biopsies). Microsatellite genotypes were used to identify individuals for a genotype recapture abundance estimate of individuals age 1⁺ (N₁₊) and for the estimation of effective population size (N[subscript e]). Both populations exhibited a high N[subscript e] relative to N₁₊, consistent with expectations given their life history characteristics and the limited data available for other dolphin species. The abundance of Maui's dolphins was confirmed to be very low, Maui's 10-11 N₁₊ = 55 (95% CL = 48 - 69), and as expected, it had much lower linkage disequilibrium N[subscript e] (61, 95% CL = 29 - 338) than Hector's CB11-12 (N[subscript e] = 207, 95% CL = 127 - 447; N₁₊ = 272, 95% CL = 236 - 323). The slightly higher Ne/N₁₊ ratio of the Maui's dolphin compared to the Hector's dolphin is consistent with a recent decline in the Maui's dolphin. Although the point estimates of both N[subscript e] and N₁₊ decreased between the two Maui's dolphin datasets (Maui's 01-07: N[subscript e] = 74, 95% CL = 37 - 318; N₁₊ = 69, 95% CL = 38 - 125), the confidence intervals widely overlapped. Maui's 10-11 had significantly fewer alleles (average 4 alleles/locus) and lower heterozygosity (H₀ = 0.316, H[subscript e] = 0.319) than Hector's CB11-12 (average 7 alleles/locus, H₀ = 0.500, H[subscript e] = 0.495; all P <0.001). Interestingly, one microsatellite locus (PPHO104) had anomalously high diversity (31 to 63 alleles) in both Hector's and Maui's dolphins and appears to be influenced by diversifying selection. The observed and expected heterozygosity, internal relatedness, and F[subscript IS] of Maui's dolphins all showed patterns consistent with a decline of the subspecies, although none differed significantly over the short time interval between the two datasets collected in 2001-07 and 2010-11. The lack of significant decline in any of the parameters analyzed for Maui's dolphins is not surprising given the low power to detect a low to moderate decline over the short interval (<1 generation) between the two sampling periods. Compared to minimum viable effective population sizes proposed to guide management decisions, the Maui's dolphin has declined below the recommended threshold of N[subscript e] = 50, recently increased to N[subscript e] ≥100, thought to be necessary to avoid inbreeding depression in the short term (5 generations, ~65.2 years for Maui's and Hector's dolphins). Additionally, both the Maui's dolphin and Cloudy Bay Hector's dolphin populations are below the recommended threshold of N[subscript e] = 500, recently increased to N[subscript e] ≥1000, thought to be necessary to preserve long-term evolutionary potential. This is less of a concern for the Cloudy Bay Hector's population, which is thought to maintain gene flow with neighboring populations. However, for the small, isolated Maui's dolphin population, inbreeding depression is likely to be an increasing concern. Furthermore, each Maui's dolphin individual holds a disproportionate amount of the total genetic variation of the subspecies and would represent a disproportionately large demographic and genetic loss if it died before realizing its reproductive potential in the population. There is, however, potential for genetic restoration by interbreeding with Hector's dolphins, as genetic monitoring of Maui's dolphins revealed the first contemporary dispersal of four (two living females, one dead female, one dead male) Hector's dolphins into the Maui's dolphin distribution. Two Hector's dolphins (one dead female neonate, one living male) were also sampled along the North Island's southwest coast, outside the presumed range of either subspecies. Together, these records provide evidence of long-distance dispersal by Hector's dolphins (≥400 km) and the possibility of an unsampled Hector's dolphin population along the southwest coast of the North Island or northern South Island. These results highlight the value of genetic monitoring for subspecies lacking distinctive physical appearances, as such discoveries are not detected by other means but have important conservation implications. Although the Maui's dolphin is critically endangered, it is not necessarily doomed to extinction. The subspecies appears to be maintaining an equal sex ratio and connectivity within its remnant range, and the highly diverse locus PPHO104 could potentially offer clues to an inbreeding avoidance mechanism. If Maui's dolphins interbreed with the recently identified Hector's dolphin immigrants, it could provide genetic restoration, enhancing chances of long-term survival of the Maui's dolphin. Continued genetic monitoring and examination of recovered carcasses for phenotypic signs of inbreeding are important for gauging genetic threats to the survival of Maui's dolphins, as well as determining if any Hector's dolphin populations appear to be declining toward the critically endangered state of the Maui's dolphin. The results of this work contributed to the decision by the New Zealand Department of Conservation and Ministry for Primary Industries to conduct an updated risk assessment for Maui's dolphins and accelerate the review of the Maui's Dolphin Threat Management Plan. Consequently, commercial and recreational set net restrictions were extended slightly to reduce entanglement risk to Maui's dolphins utilizing the southern part of their distribution, as well as any Hector's dolphins that disperse north into that area. The results related to the population of Hector's dolphins in Cloudy Bay provide information that will contribute to the upcoming review of the Hector's dolphin component of the Threat Management Plan. Title: All in a DNA's work : conservation genetics and monitoring of the New Zealand endemic Maui's and Hector's dolphins Author: Hamner, Rebecca Marie The critically endangered Maui's dolphin (Cephalorhynchus hectori maui) and the endangered Hector's dolphin (C. h. hectori) are endemic to the coastal waters of New Zealand, where their primary threat is fisheries-related mortality. The Maui's dolphin is among the most critically endangered cetaceans in the world, with its remnant population primarily concentrated in approximately 140 km along the central west coast of New Zealand's North Island. Its closely related sister subspecies, the Hector's dolphin, is more abundant and offers a useful comparison for studying the Maui's dolphin. My work used genetic tools to examine demographic and genetic parameters relevant for conservation considerations regarding Maui's and Hector's dolphins, as well as to build upon past genetic baselines for the purpose of long-term genetic monitoring of these subspecies. Three genetic datasets formed the basis for most analyses: (1) Maui's 01-07, including 54 Maui's dolphin individuals sampled between 2001 and 2007 (n = 70 biopsies, 12 beachcast); (2) Maui's 10-11, including 40 Maui's dolphin individuals sampled in 2010 and 2011 (n = 69 biopsies, 1 beachcast); and (3) Hector's CB11-12, including 148 Hector's dolphin individuals sampled in Cloudy Bay in 2011 and 2012 (n = 263 biopsies). Microsatellite genotypes were used to identify individuals for a genotype recapture abundance estimate of individuals age 1⁺ (N₁₊) and for the estimation of effective population size (N[subscript e]). Both populations exhibited a high N[subscript e] relative to N₁₊, consistent with expectations given their life history characteristics and the limited data available for other dolphin species. The abundance of Maui's dolphins was confirmed to be very low, Maui's 10-11 N₁₊ = 55 (95% CL = 48 - 69), and as expected, it had much lower linkage disequilibrium N[subscript e] (61, 95% CL = 29 - 338) than Hector's CB11-12 (N[subscript e] = 207, 95% CL = 127 - 447; N₁₊ = 272, 95% CL = 236 - 323). The slightly higher Ne/N₁₊ ratio of the Maui's dolphin compared to the Hector's dolphin is consistent with a recent decline in the Maui's dolphin. Although the point estimates of both N[subscript e] and N₁₊ decreased between the two Maui's dolphin datasets (Maui's 01-07: N[subscript e] = 74, 95% CL = 37 - 318; N₁₊ = 69, 95% CL = 38 - 125), the confidence intervals widely overlapped. Maui's 10-11 had significantly fewer alleles (average 4 alleles/locus) and lower heterozygosity (H₀ = 0.316, H[subscript e] = 0.319) than Hector's CB11-12 (average 7 alleles/locus, H₀ = 0.500, H[subscript e] = 0.495; all P <0.001). Interestingly, one microsatellite locus (PPHO104) had anomalously high diversity (31 to 63 alleles) in both Hector's and Maui's dolphins and appears to be influenced by diversifying selection. The observed and expected heterozygosity, internal relatedness, and F[subscript IS] of Maui's dolphins all showed patterns consistent with a decline of the subspecies, although none differed significantly over the short time interval between the two datasets collected in 2001-07 and 2010-11. The lack of significant decline in any of the parameters analyzed for Maui's dolphins is not surprising given the low power to detect a low to moderate decline over the short interval (<1 generation) between the two sampling periods. Compared to minimum viable effective population sizes proposed to guide management decisions, the Maui's dolphin has declined below the recommended threshold of N[subscript e] = 50, recently increased to N[subscript e] ≥100, thought to be necessary to avoid inbreeding depression in the short term (5 generations, ~65.2 years for Maui's and Hector's dolphins). Additionally, both the Maui's dolphin and Cloudy Bay Hector's dolphin populations are below the recommended threshold of N[subscript e] = 500, recently increased to N[subscript e] ≥1000, thought to be necessary to preserve long-term evolutionary potential. This is less of a concern for the Cloudy Bay Hector's population, which is thought to maintain gene flow with neighboring populations. However, for the small, isolated Maui's dolphin population, inbreeding depression is likely to be an increasing concern. Furthermore, each Maui's dolphin individual holds a disproportionate amount of the total genetic variation of the subspecies and would represent a disproportionately large demographic and genetic loss if it died before realizing its reproductive potential in the population. There is, however, potential for genetic restoration by interbreeding with Hector's dolphins, as genetic monitoring of Maui's dolphins revealed the first contemporary dispersal of four (two living females, one dead female, one dead male) Hector's dolphins into the Maui's dolphin distribution. Two Hector's dolphins (one dead female neonate, one living male) were also sampled along the North Island's southwest coast, outside the presumed range of either subspecies. Together, these records provide evidence of long-distance dispersal by Hector's dolphins (≥400 km) and the possibility of an unsampled Hector's dolphin population along the southwest coast of the North Island or northern South Island. These results highlight the value of genetic monitoring for subspecies lacking distinctive physical appearances, as such discoveries are not detected by other means but have important conservation implications. Although the Maui's dolphin is critically endangered, it is not necessarily doomed to extinction. The subspecies appears to be maintaining an equal sex ratio and connectivity within its remnant range, and the highly diverse locus PPHO104 could potentially offer clues to an inbreeding avoidance mechanism. If Maui's dolphins interbreed with the recently identified Hector's dolphin immigrants, it could provide genetic restoration, enhancing chances of long-term survival of the Maui's dolphin. Continued genetic monitoring and examination of recovered carcasses for phenotypic signs of inbreeding are important for gauging genetic threats to the survival of Maui's dolphins, as well as determining if any Hector's dolphin populations appear to be declining toward the critically endangered state of the Maui's dolphin. The results of this work contributed to the decision by the New Zealand Department of Conservation and Ministry for Primary Industries to conduct an updated risk assessment for Maui's dolphins and accelerate the review of the Maui's Dolphin Threat Management Plan. Consequently, commercial and recreational set net restrictions were extended slightly to reduce entanglement risk to Maui's dolphins utilizing the southern part of their distribution, as well as any Hector's dolphins that disperse north into that area. The results related to the population of Hector's dolphins in Cloudy Bay provide information that will contribute to the upcoming review of the Hector's dolphin component of the Threat Management Plan. Close

• 375. [Article] Epichloë typhina (fungus) - Botanophila lobata (fly) interaction : an invasive "pollinator" system in its introduced range in western Oregon

  Epichloë typhina (Ascomycetes: Clavicipitaceae) is an endophytic fungus that infects perennial Pooid grasses and is the causal agent of choke disease. It is endemic to Europe and was inadvertently introduced ...

  Citation × Citation Citation Abstract Copy Title: Epichloë typhina (fungus) - Botanophila lobata (fly) interaction : an invasive "pollinator" system in its introduced range in western Oregon Author: Kaser, Joseph M. Epichloë typhina (Ascomycetes: Clavicipitaceae) is an endophytic fungus that infects perennial Pooid grasses and is the causal agent of choke disease. It is endemic to Europe and was inadvertently introduced into orchardgrass seed production fields in western Oregon. Choke disease, which was first recorded in Oregon in 1996, currently infects ~90% of cultivated orchardgrass seed fields in the region, resulting in yield losses >65%. Infective propagules (i.e. ascospores) are produced sexually by the bipolar heterothallic fungus and gamete outcross has been shown to be facilitated in the wild by Botanophila spp. (Diptera: Anthomyiidae), including Botanophila lobata. The fly - fungus interaction is generally considered to be one of obligatory mutualism based on studies conducted in areas endemism. However, recent evidence suggests that the fungus is able to sexually outcross in cultivated Oregon orchardgrass fields without the aid of fly "pollinators." Additionally, ascosporic fertilization has recently been implicated as an alternative mechanism for gamete transfer and might have important impacts on fungal reproduction in Oregon. The objectives of this study were to: 1) explore how two tightly linked species, which appear to have an obligate mutualistic relationship in areas of endemism, interact in a non-native context; 2) quantitatively examine the seasonal and diurnal presence of E. typhina ascospores in a cultivated Oregon orchardgrass field; and 3) test alternative transfer mechanisms of fungal spermatia for E. typhina. To address objective 1), the spatial variability and reproductive success of E. typhina and B. lobata were estimated during surveys of ten cultivated orchardgrass fields in 2008 and four fields in 2009. Fungal distributions were spatially aggregated at five of the study sites in 2008 and three in 2009. Fly distributions were spatially aggregated at three sites in 2008 and one in 2009. Botanophila lobata density exhibited a positive linear relationship with E. typhina density, suggestive of positive density dependence of fly oviposition with fungal density. However, fungal reproductive success was not affected by fly density or fungal density within the range of distributions observed in this study. To address objective 2), airborne ascospores were monitored in a single cultivated orchardgrass field during 2008 and 2009 using a Burkard volumetric spore trap. Ascospore production began in early to middle May and continued into late July during both years of the study. Daily ascospore production exhibited a circadian rhythm, with production peaking on average at 1:08 am and 12:36 am, in 2008 and 2009, respectively. The prolonged duration and high intensity of ascospore production during the growing season suggest a large window within which new plants are at risk to infection, and within which preventative management strategies must be adopted. To address objective 3), splash fertilization, contact fertilization and B. lobata fertilization were tested in the greenhouse. Although only two replicates were completed, both contact and splash fertilization appeared to be viable mechanisms of sexual outcross for E. typhina. The results of this study strongly indicate that E. typhina can successfully reproduce without the presence of B. lobata. Splash and contact fertilization, as well as ascosporic fertilization, provide opportunities for reproduction of the fungus in absence of fly pollinators. It appears that the fly - fungus interaction has shifted from an obligatory mutualism to facultative mutualism or simple fungivory within the introduced range in western Oregon. Title: Epichloë typhina (fungus) - Botanophila lobata (fly) interaction : an invasive "pollinator" system in its introduced range in western Oregon Author: Kaser, Joseph M. Epichloë typhina (Ascomycetes: Clavicipitaceae) is an endophytic fungus that infects perennial Pooid grasses and is the causal agent of choke disease. It is endemic to Europe and was inadvertently introduced into orchardgrass seed production fields in western Oregon. Choke disease, which was first recorded in Oregon in 1996, currently infects ~90% of cultivated orchardgrass seed fields in the region, resulting in yield losses >65%. Infective propagules (i.e. ascospores) are produced sexually by the bipolar heterothallic fungus and gamete outcross has been shown to be facilitated in the wild by Botanophila spp. (Diptera: Anthomyiidae), including Botanophila lobata. The fly - fungus interaction is generally considered to be one of obligatory mutualism based on studies conducted in areas endemism. However, recent evidence suggests that the fungus is able to sexually outcross in cultivated Oregon orchardgrass fields without the aid of fly "pollinators." Additionally, ascosporic fertilization has recently been implicated as an alternative mechanism for gamete transfer and might have important impacts on fungal reproduction in Oregon. The objectives of this study were to: 1) explore how two tightly linked species, which appear to have an obligate mutualistic relationship in areas of endemism, interact in a non-native context; 2) quantitatively examine the seasonal and diurnal presence of E. typhina ascospores in a cultivated Oregon orchardgrass field; and 3) test alternative transfer mechanisms of fungal spermatia for E. typhina. To address objective 1), the spatial variability and reproductive success of E. typhina and B. lobata were estimated during surveys of ten cultivated orchardgrass fields in 2008 and four fields in 2009. Fungal distributions were spatially aggregated at five of the study sites in 2008 and three in 2009. Fly distributions were spatially aggregated at three sites in 2008 and one in 2009. Botanophila lobata density exhibited a positive linear relationship with E. typhina density, suggestive of positive density dependence of fly oviposition with fungal density. However, fungal reproductive success was not affected by fly density or fungal density within the range of distributions observed in this study. To address objective 2), airborne ascospores were monitored in a single cultivated orchardgrass field during 2008 and 2009 using a Burkard volumetric spore trap. Ascospore production began in early to middle May and continued into late July during both years of the study. Daily ascospore production exhibited a circadian rhythm, with production peaking on average at 1:08 am and 12:36 am, in 2008 and 2009, respectively. The prolonged duration and high intensity of ascospore production during the growing season suggest a large window within which new plants are at risk to infection, and within which preventative management strategies must be adopted. To address objective 3), splash fertilization, contact fertilization and B. lobata fertilization were tested in the greenhouse. Although only two replicates were completed, both contact and splash fertilization appeared to be viable mechanisms of sexual outcross for E. typhina. The results of this study strongly indicate that E. typhina can successfully reproduce without the presence of B. lobata. Splash and contact fertilization, as well as ascosporic fertilization, provide opportunities for reproduction of the fungus in absence of fly pollinators. It appears that the fly - fungus interaction has shifted from an obligatory mutualism to facultative mutualism or simple fungivory within the introduced range in western Oregon. Close

• 376. [Article] Brown Marmorated Stink Bug (BMSB), Halyomorpha halys Taint in Wine : Impact on Wine Sensory, Effect of Wine-processing and Management Techniques

  Brown marmorated stink bug (BMSB), (Halyomorpha halys, Hemiptera: Pentatomidae) is an invasive species that damages numerous agricultural crops including grapes. Related damage include lower ...

  Citation × Citation Citation Abstract Copy Title: Brown Marmorated Stink Bug (BMSB), Halyomorpha halys Taint in Wine : Impact on Wine Sensory, Effect of Wine-processing and Management Techniques Author: Mohekar, Pallavi, 1985- Brown marmorated stink bug (BMSB), (Halyomorpha halys, Hemiptera: Pentatomidae) is an invasive species that damages numerous agricultural crops including grapes. Related damage include lower berry weight with increased exposure and cracked berries as a result of BMSB feeding activity. The insect is currently detected in 43 US states including Oregon, Washington, California, and New York. The grape and wine industries in these areas hold significant economic value. BMSB damage has already resulted in major economic loss in the agricultural industry. Current data indicates that the infestation is spreading to new regions and its population density is increasing in regions where it has been detected. Surveys show BMSB in vineyards of Oregon, Virginia and New York where BMSB can damage grapes, lowering their yield and quality. When harvested with grape clusters, BMSB can introduce volatile compounds, trans-2-decenal and tridecane, into wine. Prior work has shown that the presence of these compounds alters wine sensory. In this thesis, the focus is on analyzing BMSB’s impact on wine quality and consumer preference. Additionally, this work determines the action threshold (AT) for BMSB in the vineyard, which is likely to prove important to the grape and wine industry in designing control limits and maintaining wine quality. The first contribution of this work establishes the sensory detection threshold (DT) and consumer rejection thresholds (CRT) for trans-2-decenal in red wine. Trans-2-decenal is one of the main aroma compounds in BMSB taint, having green, cilantro-like aroma characteristics that is undesirable in wine. Results conclusively show that trans-2-decenal in wine has a negative effect on its quality. In Pinot noir, consumers were able to perceive trans-2-decenal at 1.92 µg/L (DT). Consumer preference for Pinot noir and Merlot containing trans-2-decenal decreased significantly above the concentration of 4.8 µg/L (CRT). Pinot noir containing trans-2-decenal above CRT was described as green, herbal, musty and less fruity by wine professionals. Based on such findings, the use of CRT is recommended when establishing consumer tolerance levels of trans-2-decenal in wine. The second contribution relates BMSB presence in vineyard with sensory threshold of trans-2-decenal in the finished wine. Pinot noir, Merlot and Pinot gris were produced using different densities of BMSB in grape clusters. The results of this study indicate BMSB density of three per cluster can result in Pinot noir containing trans-2-decenal at its DT and below its CRT. This density can be used as AT for BMSB in the vineyard since wines made from grapes contaminated at or greater than 3 BMSB per cluster are likely to experience low preference by wine consumers. The same BMSB density can be used to devise control measures for Merlot since trans-2-decenal CRT was found to be similar for both Pinot noir and Merlot. Pinot gris was found to be free of trans-2-decenal even at BMSB density of 1 per cluster. Therefore, we believe that BMSB may not be a concern for white wines. The third contribution provides methods to reduce BMSB taint in finished wine. This can be done by modifying the winemaking process or by applying corrective measures in the wine. During winemaking, destemming and pressing were identified to be the steps responsible for increasing BMSB taint levels in wine whereas alcoholic fermentation decreases taint levels. Consequently, finished white wine was found to be free of trans-2-decenal since fermentation occurs after pressing. However, trans-2-decenal was present in finished red wine since pressing occurs after fermentation. Taint levels in finished red wine are also affected by different pressing variants (free run versus press fraction, bladder press versus basket press), with press fraction and bladder press introducing more BMSB taint compared to free run and basket press. This information will allow winemakers to adjust processing steps in order to minimize BMSB taint levels in red wines. Further reduction in taint levels was shown to be possible through the use of reverse osmosis filtration. Alternatively, oak addition can be used to mask the sensory attributes of trans-2-decenal at the risk of introducing spicy notes into wine. None of the other common fining agents tested were found to be effective against trans-2-decenal. Taken together, this thesis contributes a number of novel insights into the impact of BMSB on red and white wine. By relating consumer thresholds and descriptive analysis with chemical and wine processing, we are able to establish control densities for the pest in the vineyard, identify key processing steps and post-fermentation treatments to reduce BMSB taint. The information contained in this thesis is likely to prove valuable to the wine industry in its struggle against BMSB. Title: Brown Marmorated Stink Bug (BMSB), Halyomorpha halys Taint in Wine : Impact on Wine Sensory, Effect of Wine-processing and Management Techniques Author: Mohekar, Pallavi, 1985- Brown marmorated stink bug (BMSB), (Halyomorpha halys, Hemiptera: Pentatomidae) is an invasive species that damages numerous agricultural crops including grapes. Related damage include lower berry weight with increased exposure and cracked berries as a result of BMSB feeding activity. The insect is currently detected in 43 US states including Oregon, Washington, California, and New York. The grape and wine industries in these areas hold significant economic value. BMSB damage has already resulted in major economic loss in the agricultural industry. Current data indicates that the infestation is spreading to new regions and its population density is increasing in regions where it has been detected. Surveys show BMSB in vineyards of Oregon, Virginia and New York where BMSB can damage grapes, lowering their yield and quality. When harvested with grape clusters, BMSB can introduce volatile compounds, trans-2-decenal and tridecane, into wine. Prior work has shown that the presence of these compounds alters wine sensory. In this thesis, the focus is on analyzing BMSB’s impact on wine quality and consumer preference. Additionally, this work determines the action threshold (AT) for BMSB in the vineyard, which is likely to prove important to the grape and wine industry in designing control limits and maintaining wine quality. The first contribution of this work establishes the sensory detection threshold (DT) and consumer rejection thresholds (CRT) for trans-2-decenal in red wine. Trans-2-decenal is one of the main aroma compounds in BMSB taint, having green, cilantro-like aroma characteristics that is undesirable in wine. Results conclusively show that trans-2-decenal in wine has a negative effect on its quality. In Pinot noir, consumers were able to perceive trans-2-decenal at 1.92 µg/L (DT). Consumer preference for Pinot noir and Merlot containing trans-2-decenal decreased significantly above the concentration of 4.8 µg/L (CRT). Pinot noir containing trans-2-decenal above CRT was described as green, herbal, musty and less fruity by wine professionals. Based on such findings, the use of CRT is recommended when establishing consumer tolerance levels of trans-2-decenal in wine. The second contribution relates BMSB presence in vineyard with sensory threshold of trans-2-decenal in the finished wine. Pinot noir, Merlot and Pinot gris were produced using different densities of BMSB in grape clusters. The results of this study indicate BMSB density of three per cluster can result in Pinot noir containing trans-2-decenal at its DT and below its CRT. This density can be used as AT for BMSB in the vineyard since wines made from grapes contaminated at or greater than 3 BMSB per cluster are likely to experience low preference by wine consumers. The same BMSB density can be used to devise control measures for Merlot since trans-2-decenal CRT was found to be similar for both Pinot noir and Merlot. Pinot gris was found to be free of trans-2-decenal even at BMSB density of 1 per cluster. Therefore, we believe that BMSB may not be a concern for white wines. The third contribution provides methods to reduce BMSB taint in finished wine. This can be done by modifying the winemaking process or by applying corrective measures in the wine. During winemaking, destemming and pressing were identified to be the steps responsible for increasing BMSB taint levels in wine whereas alcoholic fermentation decreases taint levels. Consequently, finished white wine was found to be free of trans-2-decenal since fermentation occurs after pressing. However, trans-2-decenal was present in finished red wine since pressing occurs after fermentation. Taint levels in finished red wine are also affected by different pressing variants (free run versus press fraction, bladder press versus basket press), with press fraction and bladder press introducing more BMSB taint compared to free run and basket press. This information will allow winemakers to adjust processing steps in order to minimize BMSB taint levels in red wines. Further reduction in taint levels was shown to be possible through the use of reverse osmosis filtration. Alternatively, oak addition can be used to mask the sensory attributes of trans-2-decenal at the risk of introducing spicy notes into wine. None of the other common fining agents tested were found to be effective against trans-2-decenal. Taken together, this thesis contributes a number of novel insights into the impact of BMSB on red and white wine. By relating consumer thresholds and descriptive analysis with chemical and wine processing, we are able to establish control densities for the pest in the vineyard, identify key processing steps and post-fermentation treatments to reduce BMSB taint. The information contained in this thesis is likely to prove valuable to the wine industry in its struggle against BMSB. Close

• 377. [Article] Conserving energy by safe and environmentally acceptable practices in maintaining and procuring transmission poles for long service ; August 1985

  This fifth annual Cooperative Pole Research Program report outlines our progress in the six project objectives. Improved Fumigants Sampling of previously established field tests revealed that Vorlex and ...

  Citation × Citation Citation Abstract Copy Title: Conserving energy by safe and environmentally acceptable practices in maintaining and procuring transmission poles for long service ; August 1985 Author: Oregon State University, Oregon State University. Dept. of Forest Products This fifth annual Cooperative Pole Research Program report outlines our progress in the six project objectives. Improved Fumigants Sampling of previously established field tests revealed that Vorlex and Chloropicrin continued to perform well after 15 years, while Vapam was slightly less effective. Solid methylisothiocyanate (MIT) also performed well in the field after 7 years. In additional tests, gelatin encapsulated MIT migrated through Douglas-fir heartwood with addition of moderate quantities of water to degrade the gelatin. However, in the presence of higher quantities of water or no additional water, MIT migration into the wood was slowed. In a previously established test, gelatin encapsulated MIT continues to inhibit reinfestation of poles 3 years after treatment. Pelletized MIT is a new formulation (65% active ingredient) that appears to have some promise. Preliminary tests indicate that up to 95% of the MIT is release in 24 hours, but a small quantity of MIT remains in the pellets after 63 days aeration and may pose a disposal hazard. The solid MIT formulations will permit aboveground applications, increasing the risk that MIT will come in contact with pole hardware. Preliminary tests indicate that MIT had little effect on corrosion of hot dipped, galvanized bolts attached to wood. This suggests that treatment in the crossarm zone with MIT or fumigants that produce MIT should not affect the integrity of attached hardware. i-i In addition to fumigant evaluations, we recently examined an earlier test of groundline treatments with Osmoplastic® and Hollowheart®. After 10 years, these treatments are performing reasonably well, with only a slight rise in the incidence of decay fungi in the past 4 years. We also reevaluated the effectiveness of kerfing for preventing decay and found that this process reduced the depth and width of checks, resulting in a decreased incidence of decay fungi. Kerfing appears to be a valuable method for preventing internal decay at the groundline. Cedar Sapwood Decay Control This past year, the second set of five chemicals applied to control sapwood decay were evaluated after 2 years of exposure. As in earlier evaluations using the Aspergillus bioassay, none of the chemicals approach pentachlorophenol in oil for ability to inhibit sporulation of Aspergillus niger; however, several samples from zones deep in the wood produced a slight zone of effect. This may indicate the presence of a reservoir for long-term protection against decay. Several of the chemicals including Fluor Chrome Arsenic Phenol and Ammoniacal Copper Arsenate (ACA) appear to bind to the wood and may be difficult to detect by the bioassay method. We expect to assess the effectiveness of these treatments using a soil block test. Investigations of the reliability of the Aspergillus bioassay under a variety of conditions indicated that quantity of spores, use of glass or plastic petri dishes, long-term cold storage, and the use of spray inoculum instead of flooding spores had little influence on the bioassay results with pentachiorophenol, Tributyl-tinoxide, or 3 iodo propynyl butylcarbamate; however, incubation temperature did influence assay results. The Aspergillus bioassay is a simple, effective means for estimating residual preservative levels. Bolt Holes Again this year, wood around the unprotected, control bolt holes in pole sections contained such low levels of decay fungi that evaluation of the treated poles will be delayed another year. In addition to the initial bolt hole treatments, we have begun a test to determine if gelatin encapsulated or pelletized MIT can prevent decay development in field-drilled bolt holes. The pole sections used in these tests had already begun to develop decay prior to treatment and will provide an ideal test material. Detecting Decay and Estimatin& Residual Strength of Poles Fluorescent labeled lectins used in our earlier studies detected decay fungi at low weight losses under laboratory conditions. We are currently evaluating this method for detecting fungi in increment cores removed from poles to reduce the need for culturing. Last year we identified a peak that was unique to infrared (IR) spectra of warm water extracts from decayed wood. This past year we attempted to identify the chemical responsible for this peak and found that carbonyl compounds, probably from oxidative lignin degradation, were responsible for the peak. Since brown rot fungi apparently do iv not completely metabolize lignin breakdown products, they accumulate in the decaying wood and can be readily detected by their IR spectra. Strength properties of beams cut front Douglas-fir pole sections, air-seasoned for 3 years significantly decreased although decay fungi could not be uniformly isolated from the beams. In addition, there were gradual declines in work to maximum load and modulus of elasticity, as well as increased Pilodyn pin penetration. These results suggest that some strength losses occurred during air-seasoning; however, the losses were not large and should not endanger pole users. We compared several test methods including the Pilodyn, radial compression tests, longitudinal compression tests, and the pick test for evaluating residual pole strength of the wood surface of Douglas-fir treated with combinations of funtigants or groundline wraps. The results indicate that only the pick test could accurately detect surface damage and illustrate the difficulty of detecting surface damage. This past year we evaluated several sections cut from ACA treated poles stored for a number of years to determine if they were worth salvaging. Static bending tests of beams cut from the ACA treated zone, the treated/untreated boundary, and the inner heartwood revealed ACA treated sapwood had lower MOR and longitudinal compression strength than the other zones. These results represent only a small sample, but they suggest that some strength loss occurs during ACA V treatments. More importantly, the results suggest that we could have reliably predicted beam MOR by testing small plugs removed from the poles. Small beams cut from decaying, pentachlorophenol treated Douglas-fir poles were acoustically tested for residual wood strength, then evaluated to failure in static bending. The acoustic test consisted of sending a pulsed sonic wave into the wood and recording this wave after it passed through the beam. As it moved, the wave was altered by the presence of any wood defects or decay, and these alterations create a "fingerprint" specific for that defect. Preliminary results indicated that signal analysis was highly 2 2 correlated with work to maximum load (r =.82) and MOR (r .88), suggesting that this approach to decay detection may prove more reliable than measuring of sound velocity. Initiation of Decay in Air-Seasoning Douglas-fir The results of the initial survey to determine the incidence of decay fungi in poles from widely scattered Pacific Northwest seasoning yards indicated that a variety of fungi were colonizing the wood. While most of these fungi do not pose a serious decay problem, two species, Poria carbonica and Poria placenta, became increasingly abundant with length of air-seasoning. These fungi are also the most conunon decayers of Douglas-fir poles in service. As expected, the number of fungi and the wood volume they occupied increased with seasoning time; however, this incidence varied considerably between yards, especially in poles air-seasoned for vi shorter time periods. In addition to the variation between sites, many of the decay fungi colonizing the wood appear to be monokaryons, indicating that spores landing on the wood are initiating the infestation. The distribution of fungi within the poles indicated that several of the more abundant decay fungi were present in the outer sapwood where they would be eliminated by conventional pressure treatment. The remaining fungi were most abundant in the heartwood but were more concentrated near the pole end. This suggests that exposed end grain was more readily invaded than lateral grain exposed in checks. In addition to identifying the fungi colonizing Douglas-fir, we examined the effects these fungi had on wood strength. Toughness tests indicated the presence of wide variation in decay capability of the isolates. Although there was no consistent pattern, most of the isolates did not cause substantial decay and, of those that did, only . carbonica and P. placenta were sufficiently abundant to have a large influence on wood strength. Due to the prevalence of P. carbonica and P. placenta in the inner heartwood, where they might not be eliminated in a short heating cycle, we evaluated the temperature tolerance of these two fungi in Douglas-fir heartwood blocks. These tests indicated that both fungi were eliminated by exposure to temperatures above 71°C for over 1 hour or 60°C for 2 hours. The results suggest that careful control of temperature during treatment should eliminate decay fungi and that wood treated at ambient temperatures should be heated to kill fungi that become established during air-seasoning. vii This past year was the third and final year of the decay development study. In this study, sterile pole sections have been exposed for 1, 2, or 3 years at widely scattered Pacific Northwest sites, then returned to the laboratory and extensively sampled. We are now in the process of identifying the fungi from the third year poles. In addition to examining poles prior to preservative treatment, we are also evaluating poles treated with waterborne chemicals (ACA or CCA) for the incidence of surface decay. This past year we examined twenty ACA-treated poles from a line installed in 1946. While a variety of fungi were cultured from the wood, none of the poles had evidence of substantial surface deterioration. A study was initiated on the fungal flora of fumigant treated wood because of the potential for fungi developing resistance to low levels of fumigant or the ability to actively degrade the chemical. Both of these developments could shorten fumigant retreatment cycles and increase maintenance costs. We have evaluated poles treated 7 and 15 years ago with fumigants and find markedly reduced fungal flora. Tests are continuing on the fungi isolated, and we hope to assess the effects of these isolates on long-term fumigant effectiveness. Title: Conserving energy by safe and environmentally acceptable practices in maintaining and procuring transmission poles for long service ; August 1985 Author: Oregon State University, Oregon State University. Dept. of Forest Products This fifth annual Cooperative Pole Research Program report outlines our progress in the six project objectives. Improved Fumigants Sampling of previously established field tests revealed that Vorlex and Chloropicrin continued to perform well after 15 years, while Vapam was slightly less effective. Solid methylisothiocyanate (MIT) also performed well in the field after 7 years. In additional tests, gelatin encapsulated MIT migrated through Douglas-fir heartwood with addition of moderate quantities of water to degrade the gelatin. However, in the presence of higher quantities of water or no additional water, MIT migration into the wood was slowed. In a previously established test, gelatin encapsulated MIT continues to inhibit reinfestation of poles 3 years after treatment. Pelletized MIT is a new formulation (65% active ingredient) that appears to have some promise. Preliminary tests indicate that up to 95% of the MIT is release in 24 hours, but a small quantity of MIT remains in the pellets after 63 days aeration and may pose a disposal hazard. The solid MIT formulations will permit aboveground applications, increasing the risk that MIT will come in contact with pole hardware. Preliminary tests indicate that MIT had little effect on corrosion of hot dipped, galvanized bolts attached to wood. This suggests that treatment in the crossarm zone with MIT or fumigants that produce MIT should not affect the integrity of attached hardware. i-i In addition to fumigant evaluations, we recently examined an earlier test of groundline treatments with Osmoplastic® and Hollowheart®. After 10 years, these treatments are performing reasonably well, with only a slight rise in the incidence of decay fungi in the past 4 years. We also reevaluated the effectiveness of kerfing for preventing decay and found that this process reduced the depth and width of checks, resulting in a decreased incidence of decay fungi. Kerfing appears to be a valuable method for preventing internal decay at the groundline. Cedar Sapwood Decay Control This past year, the second set of five chemicals applied to control sapwood decay were evaluated after 2 years of exposure. As in earlier evaluations using the Aspergillus bioassay, none of the chemicals approach pentachlorophenol in oil for ability to inhibit sporulation of Aspergillus niger; however, several samples from zones deep in the wood produced a slight zone of effect. This may indicate the presence of a reservoir for long-term protection against decay. Several of the chemicals including Fluor Chrome Arsenic Phenol and Ammoniacal Copper Arsenate (ACA) appear to bind to the wood and may be difficult to detect by the bioassay method. We expect to assess the effectiveness of these treatments using a soil block test. Investigations of the reliability of the Aspergillus bioassay under a variety of conditions indicated that quantity of spores, use of glass or plastic petri dishes, long-term cold storage, and the use of spray inoculum instead of flooding spores had little influence on the bioassay results with pentachiorophenol, Tributyl-tinoxide, or 3 iodo propynyl butylcarbamate; however, incubation temperature did influence assay results. The Aspergillus bioassay is a simple, effective means for estimating residual preservative levels. Bolt Holes Again this year, wood around the unprotected, control bolt holes in pole sections contained such low levels of decay fungi that evaluation of the treated poles will be delayed another year. In addition to the initial bolt hole treatments, we have begun a test to determine if gelatin encapsulated or pelletized MIT can prevent decay development in field-drilled bolt holes. The pole sections used in these tests had already begun to develop decay prior to treatment and will provide an ideal test material. Detecting Decay and Estimatin& Residual Strength of Poles Fluorescent labeled lectins used in our earlier studies detected decay fungi at low weight losses under laboratory conditions. We are currently evaluating this method for detecting fungi in increment cores removed from poles to reduce the need for culturing. Last year we identified a peak that was unique to infrared (IR) spectra of warm water extracts from decayed wood. This past year we attempted to identify the chemical responsible for this peak and found that carbonyl compounds, probably from oxidative lignin degradation, were responsible for the peak. Since brown rot fungi apparently do iv not completely metabolize lignin breakdown products, they accumulate in the decaying wood and can be readily detected by their IR spectra. Strength properties of beams cut front Douglas-fir pole sections, air-seasoned for 3 years significantly decreased although decay fungi could not be uniformly isolated from the beams. In addition, there were gradual declines in work to maximum load and modulus of elasticity, as well as increased Pilodyn pin penetration. These results suggest that some strength losses occurred during air-seasoning; however, the losses were not large and should not endanger pole users. We compared several test methods including the Pilodyn, radial compression tests, longitudinal compression tests, and the pick test for evaluating residual pole strength of the wood surface of Douglas-fir treated with combinations of funtigants or groundline wraps. The results indicate that only the pick test could accurately detect surface damage and illustrate the difficulty of detecting surface damage. This past year we evaluated several sections cut from ACA treated poles stored for a number of years to determine if they were worth salvaging. Static bending tests of beams cut from the ACA treated zone, the treated/untreated boundary, and the inner heartwood revealed ACA treated sapwood had lower MOR and longitudinal compression strength than the other zones. These results represent only a small sample, but they suggest that some strength loss occurs during ACA V treatments. More importantly, the results suggest that we could have reliably predicted beam MOR by testing small plugs removed from the poles. Small beams cut from decaying, pentachlorophenol treated Douglas-fir poles were acoustically tested for residual wood strength, then evaluated to failure in static bending. The acoustic test consisted of sending a pulsed sonic wave into the wood and recording this wave after it passed through the beam. As it moved, the wave was altered by the presence of any wood defects or decay, and these alterations create a "fingerprint" specific for that defect. Preliminary results indicated that signal analysis was highly 2 2 correlated with work to maximum load (r =.82) and MOR (r .88), suggesting that this approach to decay detection may prove more reliable than measuring of sound velocity. Initiation of Decay in Air-Seasoning Douglas-fir The results of the initial survey to determine the incidence of decay fungi in poles from widely scattered Pacific Northwest seasoning yards indicated that a variety of fungi were colonizing the wood. While most of these fungi do not pose a serious decay problem, two species, Poria carbonica and Poria placenta, became increasingly abundant with length of air-seasoning. These fungi are also the most conunon decayers of Douglas-fir poles in service. As expected, the number of fungi and the wood volume they occupied increased with seasoning time; however, this incidence varied considerably between yards, especially in poles air-seasoned for vi shorter time periods. In addition to the variation between sites, many of the decay fungi colonizing the wood appear to be monokaryons, indicating that spores landing on the wood are initiating the infestation. The distribution of fungi within the poles indicated that several of the more abundant decay fungi were present in the outer sapwood where they would be eliminated by conventional pressure treatment. The remaining fungi were most abundant in the heartwood but were more concentrated near the pole end. This suggests that exposed end grain was more readily invaded than lateral grain exposed in checks. In addition to identifying the fungi colonizing Douglas-fir, we examined the effects these fungi had on wood strength. Toughness tests indicated the presence of wide variation in decay capability of the isolates. Although there was no consistent pattern, most of the isolates did not cause substantial decay and, of those that did, only . carbonica and P. placenta were sufficiently abundant to have a large influence on wood strength. Due to the prevalence of P. carbonica and P. placenta in the inner heartwood, where they might not be eliminated in a short heating cycle, we evaluated the temperature tolerance of these two fungi in Douglas-fir heartwood blocks. These tests indicated that both fungi were eliminated by exposure to temperatures above 71°C for over 1 hour or 60°C for 2 hours. The results suggest that careful control of temperature during treatment should eliminate decay fungi and that wood treated at ambient temperatures should be heated to kill fungi that become established during air-seasoning. vii This past year was the third and final year of the decay development study. In this study, sterile pole sections have been exposed for 1, 2, or 3 years at widely scattered Pacific Northwest sites, then returned to the laboratory and extensively sampled. We are now in the process of identifying the fungi from the third year poles. In addition to examining poles prior to preservative treatment, we are also evaluating poles treated with waterborne chemicals (ACA or CCA) for the incidence of surface decay. This past year we examined twenty ACA-treated poles from a line installed in 1946. While a variety of fungi were cultured from the wood, none of the poles had evidence of substantial surface deterioration. A study was initiated on the fungal flora of fumigant treated wood because of the potential for fungi developing resistance to low levels of fumigant or the ability to actively degrade the chemical. Both of these developments could shorten fumigant retreatment cycles and increase maintenance costs. We have evaluated poles treated 7 and 15 years ago with fumigants and find markedly reduced fungal flora. Tests are continuing on the fungi isolated, and we hope to assess the effects of these isolates on long-term fumigant effectiveness. Close