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• 161. [Article] Translocation and hand-rearing of the short-tailed albatross Phoebastria albatrus: early indicators of success for species conservation and island restoration

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by Fauna & Flora International ...

  Citation × Citation Citation Abstract Copy Title: Translocation and hand-rearing of the short-tailed albatross Phoebastria albatrus: early indicators of success for species conservation and island restoration Author: Balogh, Gregory R., Sato, Fumio, Suryan, Robert M., Jacobs, Judy F., Deguchi, Tomohiro, Ozaki, Kiyoaki, Nakamura, Noboru To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by Fauna & Flora International and published by Cambridge University Press. Parts of this are a work of the U.S. Government and not subject to copyright protection in the United States. The article can be found at: http://journals.cambridge.org/action/displayJournal?jid=ORX. Title: Translocation and hand-rearing of the short-tailed albatross Phoebastria albatrus: early indicators of success for species conservation and island restoration Author: Balogh, Gregory R., Sato, Fumio, Suryan, Robert M., Jacobs, Judy F., Deguchi, Tomohiro, Ozaki, Kiyoaki, Nakamura, Noboru To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by Fauna & Flora International and published by Cambridge University Press. Parts of this are a work of the U.S. Government and not subject to copyright protection in the United States. The article can be found at: http://journals.cambridge.org/action/displayJournal?jid=ORX. Close

• 162. [Article] The study of fluo-tantalum species by solvent extraction

  The extraction of tantalum fluoride complexes by large cationic extractants (tetraphenylarsonium ion, TPA, and crystal violet) and by methyl isobutyl ketone (MIBK) has been investigated as a function of ...

  Citation × Citation Citation Abstract Copy Title: The study of fluo-tantalum species by solvent extraction Author: Coker, Marjory Carol The extraction of tantalum fluoride complexes by large cationic extractants (tetraphenylarsonium ion, TPA, and crystal violet) and by methyl isobutyl ketone (MIBK) has been investigated as a function of fluoride concentration using ¹⁸² Ta as tracer. Extractions by the cationic extractants into chloroform were carried out in the absence of a constant ionic medium because of the high extractability of perchlorate; aqueous phases contained only HF. Dependence of the distribution ratio Φ of Ta upon extractant concentration is approximately linear; at HF concentrations above 10⁻3 M the distribution is independent of metal concentration (10⁻⁷ to 10⁻⁶ M) indicating absence of polynuclear Ta species in this range. Both TPA and crystal violet exhibit a distribution maximum at 0.4 M HF (approximately 1 x 10⁻² M [F⁻]) which is probably due to the extraction of TaF₆⁻ through ion pair formation; the extraction drops sharply at higher fluoride concentrations. At HF concentrations below 10⁻³ M evidence was found for hydrolytic polymerization with one of the products extracting at about 10⁻⁴ M HF. Distribution of ¹⁸²Ta between pre-equilibrated MIBK and MIBK-saturated aqueous 1.0 M perchlorate (constant [H⁺] = 0.40, 0.70 and 1.0 M) and 2.0 M perchlorate (constant [H⁺] = 2.0 M) media maintained by HC1O₄ and NaC1O₄ was studied as a function of free fluoride concentration calculated from known HF and HC1O₄ concentrations. Increasing distribution ratios with increasing (H⁺) within the 1.0 M perchlorate system, as well as comparison of the function Φ [(F⁻)] with that expected from published tantalum fluoride formation constants, indicate the primary extracting species to be TaF₆⁻ paired with the hydrated and solvated hydronium ion. A shift in the distribution maximum to lower fluoride concentrations with increasing (H+ ) is probably due to changes in activity coefficients. This shift continues, accompanied by a change in slope of the distribution curve and a decrease in the maximum extraction, as the background electrolyte concentration is increased from 1.0 M to 2.0 M HC1O₄; the reasons for this behavior are not clear but may involve changes in hydration and solvation numbers of the extracting species as well as activity effects. Mutual solubilities of MIBK and the various aqueous media have been investigated. MIBK solubility in perchlorate solutions increases with HC1O₄ concentration. Extraction of NaC1O₄ into MIBK is practically negligible but the distribution ratio of HC1O₄ is significant, increases with acid concentration and is accompanied by the extraction of water. Evidence was found for the dissociation of HC1O₄ in MIBK. Hydrofluoric acid extracts as molecular HF and appears to be monomeric at concentrations up to about 1 M in the MIBK phase. Significant and changing aqueous phase MIBK solubilities and MIBK phase HC1O₄ and HF concentrations make it questionable whether reliable tantalum fluoride formation constants can be obtained from distribution data in this system. Title: The study of fluo-tantalum species by solvent extraction Author: Coker, Marjory Carol The extraction of tantalum fluoride complexes by large cationic extractants (tetraphenylarsonium ion, TPA, and crystal violet) and by methyl isobutyl ketone (MIBK) has been investigated as a function of fluoride concentration using ¹⁸² Ta as tracer. Extractions by the cationic extractants into chloroform were carried out in the absence of a constant ionic medium because of the high extractability of perchlorate; aqueous phases contained only HF. Dependence of the distribution ratio Φ of Ta upon extractant concentration is approximately linear; at HF concentrations above 10⁻3 M the distribution is independent of metal concentration (10⁻⁷ to 10⁻⁶ M) indicating absence of polynuclear Ta species in this range. Both TPA and crystal violet exhibit a distribution maximum at 0.4 M HF (approximately 1 x 10⁻² M [F⁻]) which is probably due to the extraction of TaF₆⁻ through ion pair formation; the extraction drops sharply at higher fluoride concentrations. At HF concentrations below 10⁻³ M evidence was found for hydrolytic polymerization with one of the products extracting at about 10⁻⁴ M HF. Distribution of ¹⁸²Ta between pre-equilibrated MIBK and MIBK-saturated aqueous 1.0 M perchlorate (constant [H⁺] = 0.40, 0.70 and 1.0 M) and 2.0 M perchlorate (constant [H⁺] = 2.0 M) media maintained by HC1O₄ and NaC1O₄ was studied as a function of free fluoride concentration calculated from known HF and HC1O₄ concentrations. Increasing distribution ratios with increasing (H⁺) within the 1.0 M perchlorate system, as well as comparison of the function Φ [(F⁻)] with that expected from published tantalum fluoride formation constants, indicate the primary extracting species to be TaF₆⁻ paired with the hydrated and solvated hydronium ion. A shift in the distribution maximum to lower fluoride concentrations with increasing (H+ ) is probably due to changes in activity coefficients. This shift continues, accompanied by a change in slope of the distribution curve and a decrease in the maximum extraction, as the background electrolyte concentration is increased from 1.0 M to 2.0 M HC1O₄; the reasons for this behavior are not clear but may involve changes in hydration and solvation numbers of the extracting species as well as activity effects. Mutual solubilities of MIBK and the various aqueous media have been investigated. MIBK solubility in perchlorate solutions increases with HC1O₄ concentration. Extraction of NaC1O₄ into MIBK is practically negligible but the distribution ratio of HC1O₄ is significant, increases with acid concentration and is accompanied by the extraction of water. Evidence was found for the dissociation of HC1O₄ in MIBK. Hydrofluoric acid extracts as molecular HF and appears to be monomeric at concentrations up to about 1 M in the MIBK phase. Significant and changing aqueous phase MIBK solubilities and MIBK phase HC1O₄ and HF concentrations make it questionable whether reliable tantalum fluoride formation constants can be obtained from distribution data in this system. Close

• 163. [Article] Responses of a threatened cutthroat trout to an introduced, invading salmonid : ecological implications for growth, stress, and behavior

  Recent studies suggest that competition from brook trout (Salvelinus fontinalis; EBT) may have negative effects (e.g. displacement) on Lahontan cutthroat trout (Oncorhynchus clarki henshawi; LCT). Results ...

  Citation × Citation Citation Abstract Copy Title: Responses of a threatened cutthroat trout to an introduced, invading salmonid : ecological implications for growth, stress, and behavior Author: Osborne-Gowey, Jeremiah D. Recent studies suggest that competition from brook trout (Salvelinus fontinalis; EBT) may have negative effects (e.g. displacement) on Lahontan cutthroat trout (Oncorhynchus clarki henshawi; LCT). Results from these studies have failed to elucidate the responsible mechanisms and have not examined if changing environmental conditions result in competitive/subordinate role reversals. The primary objectives of this study were to 1) determine if LCT and EBT compete for resources in a stream in which they co-occur, 2) determine the mechanisms responsible for the apparent competition and 3) determine if the results from competitive interactions change under variable environmental conditions. A field study examined how LCT and EBT interacted in a colonization situation typical of many LCT reintroductions, and provided insights into how LCT responded, under natural conditions, to EBT under various habitat conditions. A laboratory experiment, informed largely from the field study, was designed to force competitive interactions and measure the responses of LCT under varying habitat and environmental conditions. Results from the field manipulation revealed that EBT re-colonized a section of stream farther and faster than LCT and that about 25% of the individuals of both species stayed in the relocation pool. When in sympatry, LCT lost five times as much weight as EBT during the three week trial (2.5g to 0.5g, respectively). Lahontan cutthroat trout almost always had empty stomachs whereas EBT usually had at least some food present in their stomachs. Under laboratory conditions where density, species proportions, and temperature were manipulated, LCT typically lost weight and exhibited elevated blood plasma cortisol levels, an indicator of stress, during the 9 day trials (-8% and ~60 ng/mL, respectively) whereas EBT typically gained weight and exhibited lower cortisol levels (+1% and ~23 ng/mL). When the water temperature remained at 13°C, EBT gained an average of 5% of their body weight and had low plasma cortisol levels (~16 ng/mL) whereas LCT lost an average of 6% of their body weight and had elevated plasma cortisol levels (~40 ng/mL). As temperatures increased to 23°C, both species lost weight and exhibited elevated cortisol levels but LCT lost more weight than EBT (11% vs. 5%). As the proportion of EBT increased relative to LCT in experimental trials, LCT lost more weight and generally exhibited higher cortisol levels. Additionally, feeding observations in tanks that contained both species indicated that EBT were the first feed greater than 90% of the time, while LCT almost never fed and remained inactive when in the presence of EBT. In tanks that did not contain EBT, LCT were active and readily fed. Collectively, these results suggest that EBT are the dominant competitor and that the mechanisms for competitive dominance may, in part, be both physiological and behavioral in nature. Title: Responses of a threatened cutthroat trout to an introduced, invading salmonid : ecological implications for growth, stress, and behavior Author: Osborne-Gowey, Jeremiah D. Recent studies suggest that competition from brook trout (Salvelinus fontinalis; EBT) may have negative effects (e.g. displacement) on Lahontan cutthroat trout (Oncorhynchus clarki henshawi; LCT). Results from these studies have failed to elucidate the responsible mechanisms and have not examined if changing environmental conditions result in competitive/subordinate role reversals. The primary objectives of this study were to 1) determine if LCT and EBT compete for resources in a stream in which they co-occur, 2) determine the mechanisms responsible for the apparent competition and 3) determine if the results from competitive interactions change under variable environmental conditions. A field study examined how LCT and EBT interacted in a colonization situation typical of many LCT reintroductions, and provided insights into how LCT responded, under natural conditions, to EBT under various habitat conditions. A laboratory experiment, informed largely from the field study, was designed to force competitive interactions and measure the responses of LCT under varying habitat and environmental conditions. Results from the field manipulation revealed that EBT re-colonized a section of stream farther and faster than LCT and that about 25% of the individuals of both species stayed in the relocation pool. When in sympatry, LCT lost five times as much weight as EBT during the three week trial (2.5g to 0.5g, respectively). Lahontan cutthroat trout almost always had empty stomachs whereas EBT usually had at least some food present in their stomachs. Under laboratory conditions where density, species proportions, and temperature were manipulated, LCT typically lost weight and exhibited elevated blood plasma cortisol levels, an indicator of stress, during the 9 day trials (-8% and ~60 ng/mL, respectively) whereas EBT typically gained weight and exhibited lower cortisol levels (+1% and ~23 ng/mL). When the water temperature remained at 13°C, EBT gained an average of 5% of their body weight and had low plasma cortisol levels (~16 ng/mL) whereas LCT lost an average of 6% of their body weight and had elevated plasma cortisol levels (~40 ng/mL). As temperatures increased to 23°C, both species lost weight and exhibited elevated cortisol levels but LCT lost more weight than EBT (11% vs. 5%). As the proportion of EBT increased relative to LCT in experimental trials, LCT lost more weight and generally exhibited higher cortisol levels. Additionally, feeding observations in tanks that contained both species indicated that EBT were the first feed greater than 90% of the time, while LCT almost never fed and remained inactive when in the presence of EBT. In tanks that did not contain EBT, LCT were active and readily fed. Collectively, these results suggest that EBT are the dominant competitor and that the mechanisms for competitive dominance may, in part, be both physiological and behavioral in nature. Close

• 164. [Article] Aspects of the foraging ecology of humpback whales (Megaptera novaeangliae) in Frederick Sound and Stephens Passage, Southeast Alaska

  The North Pacific humpback whale (Megaptera novaeangliae) population has been increasing at an average annual rate of ~6% since the early 1990s. In northern Southeast Alaska alone, there are now more whales ...

  Citation × Citation Citation Abstract Copy Title: Aspects of the foraging ecology of humpback whales (Megaptera novaeangliae) in Frederick Sound and Stephens Passage, Southeast Alaska Author: Szabo, Andrew, 1974- The North Pacific humpback whale (Megaptera novaeangliae) population has been increasing at an average annual rate of ~6% since the early 1990s. In northern Southeast Alaska alone, there are now more whales than estimated for the entire North Pacific several decades ago. An understanding of how this growing population is repopulating traditional foraging grounds will benefit from detailed investigations of their prey preferences and trends in whale abundance and distribution relative to those prey. This dissertation examines these issues from late May until early September 2008 in Frederick Sound and Stephens Passage, a Southeast Alaskan feeding area historically used by humpback whales. The foundation for the study is an analysis of the life histories and abundance patterns of euphausiids, the principal prey of humpbacks in the area, during late spring and summer. Four species, Thysanoessa raschii, T. longipes, T. spinifera, and Euphausia pacifica, were identified in plankton net samples collected at random locations throughout the study site (n = 49) and in locations where a strong scattering layer was observed on a 120 kHz echosounder (n = 48). Both sample types varied in euphausiid species composition. Abundance patterns of immature euphausiids coupled with observations of females carrying spermatophores indicated differences between species in spawning schedules. Thysanoessa spp. began spawning in early April with the spring phytoplankton bloom and continued until late June, whereas E. pacifica began spawning in early June and continued until late August. This protracted recruitment of immature euphausiids was geographically widespread throughout the summer in contrast to adults, which, although present all summer, were found primarily in slope and shallow (< 100 m) areas. To determine if humpback whales preferred one euphausiid species or life-stage over another, net sample and hydroacoustic data collected in the vicinity of whales were compared to similar data collected in random locations throughout the study site. This revealed that whales targeted dense aggregations of adult euphausiids, but did not discriminate between the various species, which was surprising because of presumed differences in the energy density linked to their different spawning schedules. Additionally, whales did not spend time in areas with concentrations of immature euphausiids, which were likely not large enough during the study period to be suitable prey. With this preference for adult euphausiids, the abundance and distribution patterns of humpbacks were examined in relation to prey availability. Whale abundance was lowest at the beginning of the study in late May at ca. 68 whales and peaked in late July at ca. 228 animals – approximately 12% of the region’s estimated abundance for the study year. This study did not detect a concomitant increase in the availability of adult euphausiids, which is unsurprising since immature euphausiids would not recruit into the adult population until after the end of the study, and post-spawning mortality and predation pressure is presumably high during this time. Instead, whales clustered increasingly around comparatively fewer prey as the summer progressed. These observations, combined with a plateau in whale abundance after July, suggest that their abundance in the area was limited by euphausiid availability. Estimates of whales using the study site during the summer have remained similar over several decades despite a dramatic increase in humpback numbers in Southeast Alaska and elsewhere in the North Pacific. The results from this study suggest that, although the study site remains important seasonally to some whales, it is not a significant source of prey responsible for regional population growth in general. More likely, it is part of a network of feeding areas that has influenced the population trend. Further insight into these and the other issues raised in this dissertation could come from several additional analyses. An extended sampling season that captures the recruitment of immature euphausiids into the adult population would reveal whether a given year's prey cohort represents an important resource to whales in that same year, which has potential implications for interpreting mid-late season whale abundance patterns. As well, a photo-identification study would be useful in characterizing whale residency patterns and determining whether the abundance trends reflect a relatively small subset of the regional population using the area for most of the season or a continuous flow of a larger portion of the population. Finally, similar analyses as those outlined here but conducted in other areas within the region would provide additional insight into the network’s capacity to support the recovering whale population. Title: Aspects of the foraging ecology of humpback whales (Megaptera novaeangliae) in Frederick Sound and Stephens Passage, Southeast Alaska Author: Szabo, Andrew, 1974- The North Pacific humpback whale (Megaptera novaeangliae) population has been increasing at an average annual rate of ~6% since the early 1990s. In northern Southeast Alaska alone, there are now more whales than estimated for the entire North Pacific several decades ago. An understanding of how this growing population is repopulating traditional foraging grounds will benefit from detailed investigations of their prey preferences and trends in whale abundance and distribution relative to those prey. This dissertation examines these issues from late May until early September 2008 in Frederick Sound and Stephens Passage, a Southeast Alaskan feeding area historically used by humpback whales. The foundation for the study is an analysis of the life histories and abundance patterns of euphausiids, the principal prey of humpbacks in the area, during late spring and summer. Four species, Thysanoessa raschii, T. longipes, T. spinifera, and Euphausia pacifica, were identified in plankton net samples collected at random locations throughout the study site (n = 49) and in locations where a strong scattering layer was observed on a 120 kHz echosounder (n = 48). Both sample types varied in euphausiid species composition. Abundance patterns of immature euphausiids coupled with observations of females carrying spermatophores indicated differences between species in spawning schedules. Thysanoessa spp. began spawning in early April with the spring phytoplankton bloom and continued until late June, whereas E. pacifica began spawning in early June and continued until late August. This protracted recruitment of immature euphausiids was geographically widespread throughout the summer in contrast to adults, which, although present all summer, were found primarily in slope and shallow (< 100 m) areas. To determine if humpback whales preferred one euphausiid species or life-stage over another, net sample and hydroacoustic data collected in the vicinity of whales were compared to similar data collected in random locations throughout the study site. This revealed that whales targeted dense aggregations of adult euphausiids, but did not discriminate between the various species, which was surprising because of presumed differences in the energy density linked to their different spawning schedules. Additionally, whales did not spend time in areas with concentrations of immature euphausiids, which were likely not large enough during the study period to be suitable prey. With this preference for adult euphausiids, the abundance and distribution patterns of humpbacks were examined in relation to prey availability. Whale abundance was lowest at the beginning of the study in late May at ca. 68 whales and peaked in late July at ca. 228 animals – approximately 12% of the region’s estimated abundance for the study year. This study did not detect a concomitant increase in the availability of adult euphausiids, which is unsurprising since immature euphausiids would not recruit into the adult population until after the end of the study, and post-spawning mortality and predation pressure is presumably high during this time. Instead, whales clustered increasingly around comparatively fewer prey as the summer progressed. These observations, combined with a plateau in whale abundance after July, suggest that their abundance in the area was limited by euphausiid availability. Estimates of whales using the study site during the summer have remained similar over several decades despite a dramatic increase in humpback numbers in Southeast Alaska and elsewhere in the North Pacific. The results from this study suggest that, although the study site remains important seasonally to some whales, it is not a significant source of prey responsible for regional population growth in general. More likely, it is part of a network of feeding areas that has influenced the population trend. Further insight into these and the other issues raised in this dissertation could come from several additional analyses. An extended sampling season that captures the recruitment of immature euphausiids into the adult population would reveal whether a given year's prey cohort represents an important resource to whales in that same year, which has potential implications for interpreting mid-late season whale abundance patterns. As well, a photo-identification study would be useful in characterizing whale residency patterns and determining whether the abundance trends reflect a relatively small subset of the regional population using the area for most of the season or a continuous flow of a larger portion of the population. Finally, similar analyses as those outlined here but conducted in other areas within the region would provide additional insight into the network’s capacity to support the recovering whale population. Close

• 165. [Article] Influence of light on the growth of advance regeneration in the understory of Douglas-fir dominated forests in western Oregon

  The growth potential of Douglas-fir, grand fir and western hemlock advance regeneration in the forest understory of Douglas-fir-dominated forests was investigated to detennine the feasibility of selection ...

  Citation × Citation Citation Abstract Copy Title: Influence of light on the growth of advance regeneration in the understory of Douglas-fir dominated forests in western Oregon Author: Deisenhofer, Florian The growth potential of Douglas-fir, grand fir and western hemlock advance regeneration in the forest understory of Douglas-fir-dominated forests was investigated to detennine the feasibility of selection cutting systems in northwest Oregon. This study compared the growth of Douglas-fir, grand fir and western hemlock advance regeneration along a light gradient with hemispherical photography, modeled the relative importance of light, competition, subject tree and stand characteristics on growth and reported observations on the growth response of advance regeneration to stand manipulation. Western hemlock, grand fir and Douglas-fir advance regeneration was found at 5, 6, and 7 % of diffuse skylight in selection thinned stands respectively, indicating that all three species are capable of survival and growth in low light and, therefore, are suitable for uneven-aged management. Growth of advance regeneration in terms of height, diameter and volume followed the order: Western hemlock > Douglas-fir> grand fir, although there was seldom a significant difference between Douglas-fir and grand fir. Overtopping shrub vegetation significantly reduced growth and light availability in comparison to trees that were not overtopped. Height, radial and volume growth of all three species increased with increasing light. Regression analysis revealed that along the measured light gradient (6 44 % of diffuse skylight) i; growth of western hemlock was superior (different intercepts) to Douglas-fir at one interior Coast Range site but there was no significant difference in the relationship of growth to increased light levels (equal slopes) ii; Douglas-fir advance regeneration growth was superior (different intercepts) to grand fir at three sites but there was no significant difference in the relationship of growth to increased light levels (equal slopes). Growth modeling explained 36 to 67 % of the variation in Douglas-fir, western hemlock and grand fir advance regeneration growth and revealed that tree characteristics were better predictors of advance regeneration growth than environmental variables. Independent of species, live crown ratio was the most important variable explaining variation in absolute height growth. The best-growing trees were in general taller than competing shrub vegetation and characterized by higher live crown ratios. Western hemlock was particularly sensitive to shrub cover and grew best when shnib cover was low (< 35 %). Therefore, where possible, select future crop trees with a live crown ratio of at least 50 % for Douglas-fir and grand fir and 60 % for western hemlock and remove competing vegetation. Studying the release of midstory and understory trees at the four sites in northwestern Oregon after thinning revealed in general that Douglas-fir, grand fir and western hemlock grew better following release. However, the vigor of response differed for the three species and increased in the order of western hemlock, grand fir and Douglas-fir. Douglas-fir generally released more rapidly and more vigorously than grand fir, but also decreased more rapidly. To keep a significant proportion of the advance regeneration in a very vigorous state, thinning cycles of 6 to 10 years appear necessary. Since advance regeneration of Douglas-fir and grand fir released to thinning, thinning cycles of 10 to 15 years are possible for keeping a large proportion of the advance regeneration in stable condition. Even highly suppressed Douglas-fir were capable of release after thinning. Title: Influence of light on the growth of advance regeneration in the understory of Douglas-fir dominated forests in western Oregon Author: Deisenhofer, Florian The growth potential of Douglas-fir, grand fir and western hemlock advance regeneration in the forest understory of Douglas-fir-dominated forests was investigated to detennine the feasibility of selection cutting systems in northwest Oregon. This study compared the growth of Douglas-fir, grand fir and western hemlock advance regeneration along a light gradient with hemispherical photography, modeled the relative importance of light, competition, subject tree and stand characteristics on growth and reported observations on the growth response of advance regeneration to stand manipulation. Western hemlock, grand fir and Douglas-fir advance regeneration was found at 5, 6, and 7 % of diffuse skylight in selection thinned stands respectively, indicating that all three species are capable of survival and growth in low light and, therefore, are suitable for uneven-aged management. Growth of advance regeneration in terms of height, diameter and volume followed the order: Western hemlock > Douglas-fir> grand fir, although there was seldom a significant difference between Douglas-fir and grand fir. Overtopping shrub vegetation significantly reduced growth and light availability in comparison to trees that were not overtopped. Height, radial and volume growth of all three species increased with increasing light. Regression analysis revealed that along the measured light gradient (6 44 % of diffuse skylight) i; growth of western hemlock was superior (different intercepts) to Douglas-fir at one interior Coast Range site but there was no significant difference in the relationship of growth to increased light levels (equal slopes) ii; Douglas-fir advance regeneration growth was superior (different intercepts) to grand fir at three sites but there was no significant difference in the relationship of growth to increased light levels (equal slopes). Growth modeling explained 36 to 67 % of the variation in Douglas-fir, western hemlock and grand fir advance regeneration growth and revealed that tree characteristics were better predictors of advance regeneration growth than environmental variables. Independent of species, live crown ratio was the most important variable explaining variation in absolute height growth. The best-growing trees were in general taller than competing shrub vegetation and characterized by higher live crown ratios. Western hemlock was particularly sensitive to shrub cover and grew best when shnib cover was low (< 35 %). Therefore, where possible, select future crop trees with a live crown ratio of at least 50 % for Douglas-fir and grand fir and 60 % for western hemlock and remove competing vegetation. Studying the release of midstory and understory trees at the four sites in northwestern Oregon after thinning revealed in general that Douglas-fir, grand fir and western hemlock grew better following release. However, the vigor of response differed for the three species and increased in the order of western hemlock, grand fir and Douglas-fir. Douglas-fir generally released more rapidly and more vigorously than grand fir, but also decreased more rapidly. To keep a significant proportion of the advance regeneration in a very vigorous state, thinning cycles of 6 to 10 years appear necessary. Since advance regeneration of Douglas-fir and grand fir released to thinning, thinning cycles of 10 to 15 years are possible for keeping a large proportion of the advance regeneration in stable condition. Even highly suppressed Douglas-fir were capable of release after thinning. Close

• 166. [Article] Respiratory adaptations of two macrurousanomuran mud shrimps, Callianassa Califormiensis and Upogebia pugettensis (Decapoda, Thalassinidea)

  Callianassa californiensis Dana and Upogebia pugettensis (Dana) inhabit estuarine mudflats and are subjected to the hypoxic conditions that prevail during tidal exposure. Metabolic responses for both these ...

  Citation × Citation Citation Abstract Copy Title: Respiratory adaptations of two macrurousanomuran mud shrimps, Callianassa Califormiensis and Upogebia pugettensis (Decapoda, Thalassinidea) Author: Thompson, Rogene Kasparek Callianassa californiensis Dana and Upogebia pugettensis (Dana) inhabit estuarine mudflats and are subjected to the hypoxic conditions that prevail during tidal exposure. Metabolic responses for both these species, as indicated by critical oxygen tension, metabolic rate, and tolerance to anoxia were determined. An oxygen macro-electrode and a physiological gas analyzer in conjunction with the sealed jar method were used in all metabolic experiments. The survival time under anoxia was measured. A procedure is also described for counting heart rates of Callianassa. Field samples were analyzed for oxygen content by a micro-Winkler procedure. The ghost shrimp, Callianassa, and the blue mud shrimp, Upogebia, show metabolic adaptations for living in the mudflat biotope. Both species are good metabolic regulators. Callianassa) however, has a considerably lower critical oxygen tension (10-20 mmHg) than Upogebia (45-50 mmHg). The mean metabolic rates, within the independent range of respiration, are significantly different at the one percent level of probability. Callianassa has a metabolic rate of 0.024 mls 0₂/gm wet wt/hr compared to 0.050 mis 0₂/gm wet wt/hr for Upogebia. Data are also presented which suggest that postmolt Upogebia are relatively more oxygen dependent than intermolt shrimp and hence temporarily lose their regulatory ability. Heart rates of Callianassa subjected to diminishing oxygen concentrations show a regulatory pattern similar to that of the metabolic rate, with bradycardia occurring at low oxygen tensions. Both species survive anoxia for astonishing periods of time. The mean survival time for Callianassa is approximately 5.7 days and for Upogebia 3.3 days. It is proposed that the quantitative differences in the metabolic requirements of the two species reflect the availability of oxygen in their respective niches. Despite the fact that muds are generally more anoxic than sandy substrates Upogebia, in fact, has more oxygen available owing to a firmly constructed burrow system. Callianassa burrows are not firmly constructed and the upper reaches of the burrows tend to collapse during ebb tide. Hence, the ghost shrimps are most likely exposed directly to hypoxic interstitial waters. Preliminary field data and ecological observations support this conclusion. Upogebia burrow water has a mean concentration of 0.58 mis 0₂/l and interstitial water probably less. Title: Respiratory adaptations of two macrurousanomuran mud shrimps, Callianassa Califormiensis and Upogebia pugettensis (Decapoda, Thalassinidea) Author: Thompson, Rogene Kasparek Callianassa californiensis Dana and Upogebia pugettensis (Dana) inhabit estuarine mudflats and are subjected to the hypoxic conditions that prevail during tidal exposure. Metabolic responses for both these species, as indicated by critical oxygen tension, metabolic rate, and tolerance to anoxia were determined. An oxygen macro-electrode and a physiological gas analyzer in conjunction with the sealed jar method were used in all metabolic experiments. The survival time under anoxia was measured. A procedure is also described for counting heart rates of Callianassa. Field samples were analyzed for oxygen content by a micro-Winkler procedure. The ghost shrimp, Callianassa, and the blue mud shrimp, Upogebia, show metabolic adaptations for living in the mudflat biotope. Both species are good metabolic regulators. Callianassa) however, has a considerably lower critical oxygen tension (10-20 mmHg) than Upogebia (45-50 mmHg). The mean metabolic rates, within the independent range of respiration, are significantly different at the one percent level of probability. Callianassa has a metabolic rate of 0.024 mls 0₂/gm wet wt/hr compared to 0.050 mis 0₂/gm wet wt/hr for Upogebia. Data are also presented which suggest that postmolt Upogebia are relatively more oxygen dependent than intermolt shrimp and hence temporarily lose their regulatory ability. Heart rates of Callianassa subjected to diminishing oxygen concentrations show a regulatory pattern similar to that of the metabolic rate, with bradycardia occurring at low oxygen tensions. Both species survive anoxia for astonishing periods of time. The mean survival time for Callianassa is approximately 5.7 days and for Upogebia 3.3 days. It is proposed that the quantitative differences in the metabolic requirements of the two species reflect the availability of oxygen in their respective niches. Despite the fact that muds are generally more anoxic than sandy substrates Upogebia, in fact, has more oxygen available owing to a firmly constructed burrow system. Callianassa burrows are not firmly constructed and the upper reaches of the burrows tend to collapse during ebb tide. Hence, the ghost shrimps are most likely exposed directly to hypoxic interstitial waters. Preliminary field data and ecological observations support this conclusion. Upogebia burrow water has a mean concentration of 0.58 mis 0₂/l and interstitial water probably less. Close

• 167. [Article] The Uneven Geography of River Conservation In The U.S.: Insights From The Application Of The Wild And Scenic Rivers Act

  Rivers are vital for sustaining biodiversity and human development, yet globally only a small fraction of rivers enjoy protection and those with protections are often impaired or modified. Rapid rates ...

  Citation × Citation Citation Abstract Copy Title: The Uneven Geography of River Conservation In The U.S.: Insights From The Application Of The Wild And Scenic Rivers Act Author: Perry, Denielle Year: 2017 Rivers are vital for sustaining biodiversity and human development, yet globally only a small fraction of rivers enjoy protection and those with protections are often impaired or modified. Rapid rates of freshwater species’ extinctions indicate current conservation practices are failing. Despite over fifty years of scientific evidence justifying river conservation, it remains that less attention is focused on protecting ecosystems than on developing water resources for economic growth. This disparity is indicative of the ‘nature as resource’ versus ‘conservation of nature’ paradigm. Today, this paradigm is complicated by new attentions centering both on water resource development projects and conservation policy as climate change adaptation strategies. Policies protecting rivers are recommended for contending with more intense storms and flooding, increasing resilience for species, forests, and agricultural areas, and fostering some types of water security. Creating, implementing, and managing climate adaptation policies will require a strong state presence in water resource governance. We know, however, the aforementioned paradigm hinders conservation policymaking. Therefore, understanding how conservation policy has already been rationalized, implemented, and managed is critical to advancing climate adaptation policymaking. Yet, little empirical research has been conducted on federal river conservation policy creation or application across the U.S. To that end, this dissertation, presented in three discrete original research articles, examines the United States National Wild and Scenic Rivers System. Specifically, this study investigates the socio-ecological drivers behind the creation of the Wild and Scenic Rivers Act of 1968 (WSRA hereinafter) and the spatial dimensions of the policy’s application and management over time. This study is grounded empirically in extensive archival materials, interviews with federal land management agency personnel, conservation advocates, and technical experts, as well as spatial and temporal analysis of a geodatabase. Together, these methods were employed to answer the following research questions which guide this study: (1) What factors influence the temporal and spatial distribution of river segments protected under the Wild & Scenic Rivers Act? (2) What does the history of management in designated segments suggest about emerging trends and patterns in river conservation? (3) How are competing environmental values and ideologies understood and reconciled in the context of river conservation? Title: The Uneven Geography of River Conservation In The U.S.: Insights From The Application Of The Wild And Scenic Rivers Act Author: Perry, Denielle Year: 2017 Rivers are vital for sustaining biodiversity and human development, yet globally only a small fraction of rivers enjoy protection and those with protections are often impaired or modified. Rapid rates of freshwater species’ extinctions indicate current conservation practices are failing. Despite over fifty years of scientific evidence justifying river conservation, it remains that less attention is focused on protecting ecosystems than on developing water resources for economic growth. This disparity is indicative of the ‘nature as resource’ versus ‘conservation of nature’ paradigm. Today, this paradigm is complicated by new attentions centering both on water resource development projects and conservation policy as climate change adaptation strategies. Policies protecting rivers are recommended for contending with more intense storms and flooding, increasing resilience for species, forests, and agricultural areas, and fostering some types of water security. Creating, implementing, and managing climate adaptation policies will require a strong state presence in water resource governance. We know, however, the aforementioned paradigm hinders conservation policymaking. Therefore, understanding how conservation policy has already been rationalized, implemented, and managed is critical to advancing climate adaptation policymaking. Yet, little empirical research has been conducted on federal river conservation policy creation or application across the U.S. To that end, this dissertation, presented in three discrete original research articles, examines the United States National Wild and Scenic Rivers System. Specifically, this study investigates the socio-ecological drivers behind the creation of the Wild and Scenic Rivers Act of 1968 (WSRA hereinafter) and the spatial dimensions of the policy’s application and management over time. This study is grounded empirically in extensive archival materials, interviews with federal land management agency personnel, conservation advocates, and technical experts, as well as spatial and temporal analysis of a geodatabase. Together, these methods were employed to answer the following research questions which guide this study: (1) What factors influence the temporal and spatial distribution of river segments protected under the Wild & Scenic Rivers Act? (2) What does the history of management in designated segments suggest about emerging trends and patterns in river conservation? (3) How are competing environmental values and ideologies understood and reconciled in the context of river conservation? Close

• 168. [Article] River-dependent bird species as potential indicators of ecosystem response to removal of dams on the Elwha River, Washington

  If two dams on the Elwha River are removed, the ecosystem will be open to the downstream flow of sediments and the upstream flow of marine nutrients in the form of anadromous fish. Nutrient enrichment ...

  Citation × Citation Citation Abstract Copy Title: River-dependent bird species as potential indicators of ecosystem response to removal of dams on the Elwha River, Washington Author: Blackie, Barbara If two dams on the Elwha River are removed, the ecosystem will be open to the downstream flow of sediments and the upstream flow of marine nutrients in the form of anadromous fish. Nutrient enrichment may influence trophic dynamics of the entire ecosystem, extending beyond the aquatic boundary. I assessed the current relative densities of five river dependent bird species on the Elwha and three other rivers in Olympic National Park in Washington State to describe pretreatment reference conditions as a basis for assessment of post-treatment ecosystem responses. I also compared the amount of time that non-breeding and failed-breeding (NBIFB) female Harlequin Ducks (Histrionicus histrionicus) spent foraging on different rivers and on adjacent coastal habitat to determine whether time spent foraging could be used as an indicator of habitat preference. Surveys of key river-dependent bird species were conducted on two rivers in 1996 and on four rivers in 1997. The benthivorous foraging guild was represented by the American Dipper (Cinclus mexicanus), Harlequin Duck and Spotted Sandpiper (Actitis macularia). Harlequin Ducks had higher relative densities on the Elwha than the Hoh and Soleduck Rivers, but densities were similar to those found on the Duckabush River. There were greater numbers of Harlequin Ducks per linear kilometer above the two dams than between or below them. Relative densities of American Dippers on the Elwha were lower than on the Duckabush but not statistically different from those on the Hoh and Soleduck Rivers. Spotted Sandpipers had similar densities on all rivers except the Soleduck River where their numbers were lower. The piscivorous foraging guild was represented by the Common Merganser (Mergus merganser) and Belted Kingfisher (Ceryle alcyon). Common Mergansers were relatively more abundant on the Elwha River than on the other rivers due to their high numbers below the lowest dam where wild and hatchery anadromous fish are present. Belted Kingfisher relative densities showed no significant differences between rivers as they were found in low numbers on all rivers. Using relative abundances of some river dependent bird species as indicators of ecosystem recovery after dam removal may be useful tool surveys are continued throughout the process. In spite of lack of anadromy, the Elwha River ecosystem supports a significant population of Harlequin Ducks when compared to other Olympic rivers. American Dippers are also well represented on the Elwha River, specifically above the dams. Because of their relative abundance, these benthivore populations may have a measurable, upriver response to any nutrient enrichment as a result of dam removal and both species should be monitored. The Duckabush River, with a similar Harlequin Duck relative abundance in the lower reaches, should be monitored concurrently to account for region-wide population shifts of that species over time. The Common Merganser may be the best indicator of below dam effects on the Elwha River and numbers could be compared with the lower Soleduck River, however alternative survey methods, specifically drift boat surveys, should be considered to improve count accuracy. During June and July of 1997, time-activity budget data were gathered on NB/FB Harlequin Ducks on the Elwha, Duckabush and Dosewallips Rivers and at their mouths and at the mouth of Salt Creek. Time spent foraging by NBIFB Harlequin Ducks was similar among the three rivers examined. NB/FB Harlequin Ducks on the spent 33.1%, 33.2%, 36.4% of their time feeding, on the Elwha, Duckabush Dosewallips Rivers respectively. The Elwha River system was the only system where time activity budgets could be compared between river and adjacent coastal habitats. Time spent foraging at the mouth of the Elwha was significantly higher (52.5%) than on the Elwha River proper. Food availability on river habitat may be a factor in NB/FB females' decision to remain on river habitat during the breeding season or migrate to the ocean. Time-activity budgets provide information on Harlequin Duck life history but a better understanding of their foraging behavior and the role of food availability in habitat selection is needed before time-activity budgets alone can be used as a tool for assessing ecosystem response to dam removal. Time-activity budget data collected concurrently with food availability data from field studies, along with energetics and food preference data from field or laboratory studies may establish a clearer link between time spent feeding and habitat quality and preferences. Title: River-dependent bird species as potential indicators of ecosystem response to removal of dams on the Elwha River, Washington Author: Blackie, Barbara If two dams on the Elwha River are removed, the ecosystem will be open to the downstream flow of sediments and the upstream flow of marine nutrients in the form of anadromous fish. Nutrient enrichment may influence trophic dynamics of the entire ecosystem, extending beyond the aquatic boundary. I assessed the current relative densities of five river dependent bird species on the Elwha and three other rivers in Olympic National Park in Washington State to describe pretreatment reference conditions as a basis for assessment of post-treatment ecosystem responses. I also compared the amount of time that non-breeding and failed-breeding (NBIFB) female Harlequin Ducks (Histrionicus histrionicus) spent foraging on different rivers and on adjacent coastal habitat to determine whether time spent foraging could be used as an indicator of habitat preference. Surveys of key river-dependent bird species were conducted on two rivers in 1996 and on four rivers in 1997. The benthivorous foraging guild was represented by the American Dipper (Cinclus mexicanus), Harlequin Duck and Spotted Sandpiper (Actitis macularia). Harlequin Ducks had higher relative densities on the Elwha than the Hoh and Soleduck Rivers, but densities were similar to those found on the Duckabush River. There were greater numbers of Harlequin Ducks per linear kilometer above the two dams than between or below them. Relative densities of American Dippers on the Elwha were lower than on the Duckabush but not statistically different from those on the Hoh and Soleduck Rivers. Spotted Sandpipers had similar densities on all rivers except the Soleduck River where their numbers were lower. The piscivorous foraging guild was represented by the Common Merganser (Mergus merganser) and Belted Kingfisher (Ceryle alcyon). Common Mergansers were relatively more abundant on the Elwha River than on the other rivers due to their high numbers below the lowest dam where wild and hatchery anadromous fish are present. Belted Kingfisher relative densities showed no significant differences between rivers as they were found in low numbers on all rivers. Using relative abundances of some river dependent bird species as indicators of ecosystem recovery after dam removal may be useful tool surveys are continued throughout the process. In spite of lack of anadromy, the Elwha River ecosystem supports a significant population of Harlequin Ducks when compared to other Olympic rivers. American Dippers are also well represented on the Elwha River, specifically above the dams. Because of their relative abundance, these benthivore populations may have a measurable, upriver response to any nutrient enrichment as a result of dam removal and both species should be monitored. The Duckabush River, with a similar Harlequin Duck relative abundance in the lower reaches, should be monitored concurrently to account for region-wide population shifts of that species over time. The Common Merganser may be the best indicator of below dam effects on the Elwha River and numbers could be compared with the lower Soleduck River, however alternative survey methods, specifically drift boat surveys, should be considered to improve count accuracy. During June and July of 1997, time-activity budget data were gathered on NB/FB Harlequin Ducks on the Elwha, Duckabush and Dosewallips Rivers and at their mouths and at the mouth of Salt Creek. Time spent foraging by NBIFB Harlequin Ducks was similar among the three rivers examined. NB/FB Harlequin Ducks on the spent 33.1%, 33.2%, 36.4% of their time feeding, on the Elwha, Duckabush Dosewallips Rivers respectively. The Elwha River system was the only system where time activity budgets could be compared between river and adjacent coastal habitats. Time spent foraging at the mouth of the Elwha was significantly higher (52.5%) than on the Elwha River proper. Food availability on river habitat may be a factor in NB/FB females' decision to remain on river habitat during the breeding season or migrate to the ocean. Time-activity budgets provide information on Harlequin Duck life history but a better understanding of their foraging behavior and the role of food availability in habitat selection is needed before time-activity budgets alone can be used as a tool for assessing ecosystem response to dam removal. Time-activity budget data collected concurrently with food availability data from field studies, along with energetics and food preference data from field or laboratory studies may establish a clearer link between time spent feeding and habitat quality and preferences. Close

• 169. [Article] Competitive Interactions and Resource Partitioning Between Northern Spotted Owls and Barred Owls in Western Oregon

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the Wildlife Society ...

  Citation × Citation Citation Abstract Copy Title: Competitive Interactions and Resource Partitioning Between Northern Spotted Owls and Barred Owls in Western Oregon Author: Forsman, Eric D., Anthony, Robert G., Wiens, J. David To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the Wildlife Society and published by John Wiley & Sons, Ltd. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291938-5455. Title: Competitive Interactions and Resource Partitioning Between Northern Spotted Owls and Barred Owls in Western Oregon Author: Forsman, Eric D., Anthony, Robert G., Wiens, J. David To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the Wildlife Society and published by John Wiley & Sons, Ltd. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291938-5455. Close

• 170. [Article] State of the California Current 2014-15: Impacts of the Warm-Water "Blob"

  Physical supporting data from this document has been moved to an online supplement (www.calcofi.org/ccpublications/ state-of-the-california-current-live-supplement.html).

  Citation × Citation Citation Abstract Copy Title: State of the California Current 2014-15: Impacts of the Warm-Water "Blob" Author: Gaxiola-Castro, Gilberto, Field, John, Suryan, Robert M., Schneider, Stephanie R., Barceló, Caren, Sakuma, Keith, McClatchie, Sam, Durazo, Reginaldo, Auth, Toby D., Bradley, Russell, Watson, William, Robertson, Roxanne R., Brodeur, Ric, Bjorkstedt, Eric P., Weber, Edward D., Abell, Jeffrey, Sydeman, William J., Golightly, Richard T., Goericke, Ralf, Daly, Elizabeth A., Leising, Andrew W., Melin, Sharon R., Morgan, Cheryl, Warybok, Peter, Porquez, Jessica M., Santora, Jarrod A., Gladics, Amanda J., Schroeder, Isaac D., Chavez, Francisco P., Peterson, William T., Bograd, Steven J., Fisher, Jennifer Physical supporting data from this document has been moved to an online supplement (www.calcofi.org/ccpublications/ state-of-the-california-current-live-supplement.html). Title: State of the California Current 2014-15: Impacts of the Warm-Water "Blob" Author: Gaxiola-Castro, Gilberto, Field, John, Suryan, Robert M., Schneider, Stephanie R., Barceló, Caren, Sakuma, Keith, McClatchie, Sam, Durazo, Reginaldo, Auth, Toby D., Bradley, Russell, Watson, William, Robertson, Roxanne R., Brodeur, Ric, Bjorkstedt, Eric P., Weber, Edward D., Abell, Jeffrey, Sydeman, William J., Golightly, Richard T., Goericke, Ralf, Daly, Elizabeth A., Leising, Andrew W., Melin, Sharon R., Morgan, Cheryl, Warybok, Peter, Porquez, Jessica M., Santora, Jarrod A., Gladics, Amanda J., Schroeder, Isaac D., Chavez, Francisco P., Peterson, William T., Bograd, Steven J., Fisher, Jennifer Physical supporting data from this document has been moved to an online supplement (www.calcofi.org/ccpublications/ state-of-the-california-current-live-supplement.html). Close