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• 1. [Article] Nesting ecology of mallards in the Willamette Valley of Oregon

  Although widely studied in many portions of North America, little is known about the specific habitat requirements of mallard ducks (Anas platyrhynchos) during the breeding season in western Oregon. I ...

  Citation × Citation Citation Abstract Copy Title: Nesting ecology of mallards in the Willamette Valley of Oregon Author: Rickerson, Eric V. Although widely studied in many portions of North America, little is known about the specific habitat requirements of mallard ducks (Anas platyrhynchos) during the breeding season in western Oregon. I radio-marked 72 female mallards in the Willamette Valley of Oregon in March-April 1995-96 to document wetland habitat selection during pre-nesting and nesting phases, nesting cover selection, nesting and female success rates, nesting chronology, and survival of females during the pre-nesting and nesting periods. Wetland habitat selection was higher for seasonal riverine and permanent lacustrine habitats during the pre-nesting and nesting periods. Uncultivated upland and wetland habitat nesting sites with a strong cover component had a higher selection ranking compared to agricultural cropland and ash-cottonwood riparian. The reproductive period was 107 days beginning in early-March and concluding in late-June with the peak of nest attempts occurring around May 9. Nesting effort was low with 38.4% of females failing to attempts at least one nest. Nest survival probabilities ranged from 0.106 in 1995 to 0.216 in 1996 with a pooled estimate of 0.186 (95% C.I.=0.122-0.298). Mammalian predation accounted for 84% of nest failures. Overall female success was 40.5% and differed between first year (SY) and second year and older females (ASY). Female survival probabilities ranged from 0.5 11 in 1995 to 0.733 in 1996, with a pooled estimate of 0.668 (95% C.I.=0.5370.842). Title: Nesting ecology of mallards in the Willamette Valley of Oregon Author: Rickerson, Eric V. Although widely studied in many portions of North America, little is known about the specific habitat requirements of mallard ducks (Anas platyrhynchos) during the breeding season in western Oregon. I radio-marked 72 female mallards in the Willamette Valley of Oregon in March-April 1995-96 to document wetland habitat selection during pre-nesting and nesting phases, nesting cover selection, nesting and female success rates, nesting chronology, and survival of females during the pre-nesting and nesting periods. Wetland habitat selection was higher for seasonal riverine and permanent lacustrine habitats during the pre-nesting and nesting periods. Uncultivated upland and wetland habitat nesting sites with a strong cover component had a higher selection ranking compared to agricultural cropland and ash-cottonwood riparian. The reproductive period was 107 days beginning in early-March and concluding in late-June with the peak of nest attempts occurring around May 9. Nesting effort was low with 38.4% of females failing to attempts at least one nest. Nest survival probabilities ranged from 0.106 in 1995 to 0.216 in 1996 with a pooled estimate of 0.186 (95% C.I.=0.122-0.298). Mammalian predation accounted for 84% of nest failures. Overall female success was 40.5% and differed between first year (SY) and second year and older females (ASY). Female survival probabilities ranged from 0.5 11 in 1995 to 0.733 in 1996, with a pooled estimate of 0.668 (95% C.I.=0.5370.842). Close

• 2. [Article] Floodplain emergent wetlands as rearing habitat for fishes and the implications for wetland enhancement

  Seasonal emergent wetlands in the Pacific Northwest have not been regarded traditionally as fish rearing habitat, despite access to such habitat when river flows overtop riverbanks and connect to the floodplain. ...

  Citation × Citation Citation Abstract Copy Title: Floodplain emergent wetlands as rearing habitat for fishes and the implications for wetland enhancement Author: Henning, Julie A. Seasonal emergent wetlands in the Pacific Northwest have not been regarded traditionally as fish rearing habitat, despite access to such habitat when river flows overtop riverbanks and connect to the floodplain. As a result, restoration and enhancement projects to remediate for the loss of such wetland habitat are being implemented for waterfowl and other wildlife with little consideration for fishes such as juvenile salmon (Oncorhynchus spp.). The objectives of this study were to examine the degree to which fish utilize emergent wetlands and to determine the influence of wetland enhancement on fish communities in the Chehalis River floodplain. Furthermore, I quantified the influence of enhanced wetlands on juvenile coho salmon. A minimum of 18 fish species utilized floodplain wetlands, and the most abundant were three-spine stickleback (Gasterosteus aculeatus) and Olympic mudminnow (Novumbra hubbsi). Both enhanced and unenhanced emergent wetlands had higher abundances of nongame native fishes than oxbow habitats. Coho salmon (Oncorhynchus kisutch) was the dominant salmonid at all sites and enhanced wetlands had significantly higher abundances of yearling coho salmon than unenhanced wetlands. Dissolved oxygen concentrations decreased in emergent wetlands throughout the season and were near lethal limits for juvenile salmon by June each year. Survival of fishes utilizing emergent wetlands was dependent on movement to the river before water quality decreased and/or the wetland became isolated and stranding occurred. Emigration patterns suggested that coho salmon yearling and young-of-the-year emigrated as habitat conditions declined. This was further supported by the results of the experimental release of yearling coho salmon. Yearling coho salmon benefited from rearing in enhanced wetland habitats where their growth and survival were comparable to studies of juvenile coho off-channel habitats. Title: Floodplain emergent wetlands as rearing habitat for fishes and the implications for wetland enhancement Author: Henning, Julie A. Seasonal emergent wetlands in the Pacific Northwest have not been regarded traditionally as fish rearing habitat, despite access to such habitat when river flows overtop riverbanks and connect to the floodplain. As a result, restoration and enhancement projects to remediate for the loss of such wetland habitat are being implemented for waterfowl and other wildlife with little consideration for fishes such as juvenile salmon (Oncorhynchus spp.). The objectives of this study were to examine the degree to which fish utilize emergent wetlands and to determine the influence of wetland enhancement on fish communities in the Chehalis River floodplain. Furthermore, I quantified the influence of enhanced wetlands on juvenile coho salmon. A minimum of 18 fish species utilized floodplain wetlands, and the most abundant were three-spine stickleback (Gasterosteus aculeatus) and Olympic mudminnow (Novumbra hubbsi). Both enhanced and unenhanced emergent wetlands had higher abundances of nongame native fishes than oxbow habitats. Coho salmon (Oncorhynchus kisutch) was the dominant salmonid at all sites and enhanced wetlands had significantly higher abundances of yearling coho salmon than unenhanced wetlands. Dissolved oxygen concentrations decreased in emergent wetlands throughout the season and were near lethal limits for juvenile salmon by June each year. Survival of fishes utilizing emergent wetlands was dependent on movement to the river before water quality decreased and/or the wetland became isolated and stranding occurred. Emigration patterns suggested that coho salmon yearling and young-of-the-year emigrated as habitat conditions declined. This was further supported by the results of the experimental release of yearling coho salmon. Yearling coho salmon benefited from rearing in enhanced wetland habitats where their growth and survival were comparable to studies of juvenile coho off-channel habitats. Close

• 3. [Article] Food abundance and energetic carrying capacity for wintering waterfowl in the Great Salt Lake wetlands

  Great Salt Lake (GSL), Utah, is surrounded by 191,884 hectares of wetlands. These wetlands provide critical habitat for hundreds of thousands of breeding, migrating and wintering waterfowl each year. ...

  Citation × Citation Citation Abstract Copy Title: Food abundance and energetic carrying capacity for wintering waterfowl in the Great Salt Lake wetlands Author: Johnson, Amber Marie Great Salt Lake (GSL), Utah, is surrounded by 191,884 hectares of wetlands. These wetlands provide critical habitat for hundreds of thousands of breeding, migrating and wintering waterfowl each year. As the human population around GSL increases, government officials have proposed to divert more water from the Jordan, Ogden, and Bear Rivers to meet municipal demands. Freshwater diversions from the rivers that supply the wetlands will likely decrease the amount of wetland habitat available to waterfowl. To justify current and future water allocation for wetlands around the GSL, managers must quantify the value of these habitats to migratory wetland birds, and one measure of habitat quality is food abundance. However, food abundance in the GSL wetlands is unknown. In this study, I quantified food abundance in managed and unmanaged wetland areas along the east side of the GSL. Managed wetlands included state, federal, and private lands contained within levees and actively managed as waterfowl habitat. I defined unmanaged wetlands as those shallow water areas outside levees impacted by freshwater flows from the Jordan, Bear, and Ogden Rivers and from managed wetlands. Unmanaged wetlands are under no specific management regime and are under the greatest threat by proposed water diversions because they are currently not protected under Utah water laws. I used multi-stage and simple random sampling to quantify food abundance in managed and unmanaged wetland. Sampling in managed wetlands occurred during September 2005-2006 (n = 12) and unmanaged wetlands during 2006 (n = 3) before the majority of waterfowl arrive on fall migration. I estimated the biomass of seeds, tubers, invertebrates, and submerged aquatic vegetation (SAV). Mean tuber and invertebrate biomass was similar between managed and unmanaged wetlands in 2006 (ps > 0.09); however, leafy biomass was 37% higher in unmanaged wetlands (t = 2.47, p = 0.015) and seed biomass was 65% higher in managed wetlands (t = 5.06, p <0.001). I then used biomass estimates to calculate energetic carrying capacity of both managed and unmanaged wetland habitats and determine the effects of possible water diversions from unmanaged wetlands on migratory waterfowl. I used information on daily bird energy needs, biomass estimates, and true metabolizable energy of each food type to estimate duck carrying capacity in habitats dominated by submerged aquatic vegetation. I separated ducks into three guilds based on food habits and feeding methods (dabblers, divers and grazers). The unit of comparison for energetic carrying capacity was Duck Use Day (DUD), defined as the amount of energy needed to support one duck for one day. Carrying capacity was higher in managed vs. unmanaged habitats for all three duck foraging guilds. If unmanaged wetlands decline by 80%, I estimated that duck carrying capacity would decrease 34% for grazers, 20% for divers, and 14% for dabblers. Results from this research provide a quantitative value to both managed and unmanaged wetlands surrounding the GSL to wintering waterfowl and provide guidance for the future conservation, restoration and maintenance of hundreds of thousands of hectares of critical wetland habitat. Title: Food abundance and energetic carrying capacity for wintering waterfowl in the Great Salt Lake wetlands Author: Johnson, Amber Marie Great Salt Lake (GSL), Utah, is surrounded by 191,884 hectares of wetlands. These wetlands provide critical habitat for hundreds of thousands of breeding, migrating and wintering waterfowl each year. As the human population around GSL increases, government officials have proposed to divert more water from the Jordan, Ogden, and Bear Rivers to meet municipal demands. Freshwater diversions from the rivers that supply the wetlands will likely decrease the amount of wetland habitat available to waterfowl. To justify current and future water allocation for wetlands around the GSL, managers must quantify the value of these habitats to migratory wetland birds, and one measure of habitat quality is food abundance. However, food abundance in the GSL wetlands is unknown. In this study, I quantified food abundance in managed and unmanaged wetland areas along the east side of the GSL. Managed wetlands included state, federal, and private lands contained within levees and actively managed as waterfowl habitat. I defined unmanaged wetlands as those shallow water areas outside levees impacted by freshwater flows from the Jordan, Bear, and Ogden Rivers and from managed wetlands. Unmanaged wetlands are under no specific management regime and are under the greatest threat by proposed water diversions because they are currently not protected under Utah water laws. I used multi-stage and simple random sampling to quantify food abundance in managed and unmanaged wetland. Sampling in managed wetlands occurred during September 2005-2006 (n = 12) and unmanaged wetlands during 2006 (n = 3) before the majority of waterfowl arrive on fall migration. I estimated the biomass of seeds, tubers, invertebrates, and submerged aquatic vegetation (SAV). Mean tuber and invertebrate biomass was similar between managed and unmanaged wetlands in 2006 (ps > 0.09); however, leafy biomass was 37% higher in unmanaged wetlands (t = 2.47, p = 0.015) and seed biomass was 65% higher in managed wetlands (t = 5.06, p <0.001). I then used biomass estimates to calculate energetic carrying capacity of both managed and unmanaged wetland habitats and determine the effects of possible water diversions from unmanaged wetlands on migratory waterfowl. I used information on daily bird energy needs, biomass estimates, and true metabolizable energy of each food type to estimate duck carrying capacity in habitats dominated by submerged aquatic vegetation. I separated ducks into three guilds based on food habits and feeding methods (dabblers, divers and grazers). The unit of comparison for energetic carrying capacity was Duck Use Day (DUD), defined as the amount of energy needed to support one duck for one day. Carrying capacity was higher in managed vs. unmanaged habitats for all three duck foraging guilds. If unmanaged wetlands decline by 80%, I estimated that duck carrying capacity would decrease 34% for grazers, 20% for divers, and 14% for dabblers. Results from this research provide a quantitative value to both managed and unmanaged wetlands surrounding the GSL to wintering waterfowl and provide guidance for the future conservation, restoration and maintenance of hundreds of thousands of hectares of critical wetland habitat. Close

• 4. [Article] Areal distribution, change, and restoration potential of wetlands within the lower Columbia River riparian zone, 1948-1991

  The lower Columbia River (LCR) riparian zone is rich in habitat diversity. However, the natural beauty and species diversity along the river have increasingly become affected by human activity. This study ...

  Citation × Citation Citation Abstract Copy Title: Areal distribution, change, and restoration potential of wetlands within the lower Columbia River riparian zone, 1948-1991 Author: Allen, Tracy Hunter The lower Columbia River (LCR) riparian zone is rich in habitat diversity. However, the natural beauty and species diversity along the river have increasingly become affected by human activity. This study quantifies the areal extent and degree of wetlands change and associated causes along the LCR over the past 44 years. This research examines the distribution of wetland types and their patterns of change, developing regional models which rank areas most conducive to potential wetland recovery or restoration efforts. The length of the study area totals 234 river kilometers, from the mouth of the Columbia River to Bonneville Dam. The width includes the active channel and an approximately three-kilometer swath on either side of the river. Aerial photography was the primary means for interpreting historical extent of wetlands, using five photo dates (1948, 1961, 1973, 1983, and 1991), based upon their time interval, coverage, and photo quality. For each photo throughout the entire study site, land uses and wetland habitats greater than one hectare were identified and classified. Each classified polygon was digitized and spatially analyzed using a Geographic Information System. This study indicates that wetland habitats which were once contiguously draped upon the linear features of the river are decreasing in size and becoming fragmented. There have been both increases and decreases in specific wetland habitat areas which vary by river reach, even though wetlands have diminished overall. The estuarine section of the LCR experienced a 25% net decrease in wetland area between 1948 and 1991, while the riverine tidal section fostered a 1% increase. The riverine lower perennial section sustained the greatest loss of wetlands, which decreased by 37%. Causes for wetland losses in the estuarine section were largely related to in-water activities, such as channelization, while the causes for declines in the riverine lower perennial section were correlated with rapid urbanization. Wetland increases in the riverine tidal section were generally influenced by significant growth in palustrine and forested wetlands associated with the establishment of wildlife refuges and the incremental increase of upstream flood storage capacity. This research provides a template for identifying degraded or displaced wetlands. Through the use of a GIS, each historical wetland was ranked in either low, moderate, or high categories for restoration potential. GIS technology permits focused, sequentially-refined queries to identify potential restoration or recovery sites. In the estuarine section, 74 historical wetland sites were ranked high for restoration potential, while in the riverine tidal and riverine lower perennial sections, there were 178 and 105, respectively. Overall, these sites represent only 25% of the area occupied by wetlands in 1948. While this study advocates restoration potential, restoration is not a surrogate for responsible ecosystem-wide stewardship of the riparian zone. Restoration will not succeed unless degrading factors are mitigated or eliminated. Title: Areal distribution, change, and restoration potential of wetlands within the lower Columbia River riparian zone, 1948-1991 Author: Allen, Tracy Hunter The lower Columbia River (LCR) riparian zone is rich in habitat diversity. However, the natural beauty and species diversity along the river have increasingly become affected by human activity. This study quantifies the areal extent and degree of wetlands change and associated causes along the LCR over the past 44 years. This research examines the distribution of wetland types and their patterns of change, developing regional models which rank areas most conducive to potential wetland recovery or restoration efforts. The length of the study area totals 234 river kilometers, from the mouth of the Columbia River to Bonneville Dam. The width includes the active channel and an approximately three-kilometer swath on either side of the river. Aerial photography was the primary means for interpreting historical extent of wetlands, using five photo dates (1948, 1961, 1973, 1983, and 1991), based upon their time interval, coverage, and photo quality. For each photo throughout the entire study site, land uses and wetland habitats greater than one hectare were identified and classified. Each classified polygon was digitized and spatially analyzed using a Geographic Information System. This study indicates that wetland habitats which were once contiguously draped upon the linear features of the river are decreasing in size and becoming fragmented. There have been both increases and decreases in specific wetland habitat areas which vary by river reach, even though wetlands have diminished overall. The estuarine section of the LCR experienced a 25% net decrease in wetland area between 1948 and 1991, while the riverine tidal section fostered a 1% increase. The riverine lower perennial section sustained the greatest loss of wetlands, which decreased by 37%. Causes for wetland losses in the estuarine section were largely related to in-water activities, such as channelization, while the causes for declines in the riverine lower perennial section were correlated with rapid urbanization. Wetland increases in the riverine tidal section were generally influenced by significant growth in palustrine and forested wetlands associated with the establishment of wildlife refuges and the incremental increase of upstream flood storage capacity. This research provides a template for identifying degraded or displaced wetlands. Through the use of a GIS, each historical wetland was ranked in either low, moderate, or high categories for restoration potential. GIS technology permits focused, sequentially-refined queries to identify potential restoration or recovery sites. In the estuarine section, 74 historical wetland sites were ranked high for restoration potential, while in the riverine tidal and riverine lower perennial sections, there were 178 and 105, respectively. Overall, these sites represent only 25% of the area occupied by wetlands in 1948. While this study advocates restoration potential, restoration is not a surrogate for responsible ecosystem-wide stewardship of the riparian zone. Restoration will not succeed unless degrading factors are mitigated or eliminated. Close

• 5. [Article] Siletz Bay National Fish and Wildlife Refuge : environmental assessment

  "The Service is proposing to establish the Siletz Bay National Fish and Wildlife Refuge by initially accepting a donation of 46 acres of salt marsh, acquiring up to 793 acres of land, and cooperatively ...

  Citation × Citation Citation Abstract Copy Title: Siletz Bay National Fish and Wildlife Refuge : environmental assessment Author: U.S. Fish and Wildlife Service. Region 1, Harrison, Ben "The Service is proposing to establish the Siletz Bay National Fish and Wildlife Refuge by initially accepting a donation of 46 acres of salt marsh, acquiring up to 793 acres of land, and cooperatively managing 1,060 acres of tidelands with the State of Oregon... The primary need for the Service acquisition is to preserve diverse coastal wetland habitats and upland buffers for a variety of waterfowl, shorebirds, marine mammals, endangered species, raptors, songbirds, anadromous and resident fish, and other wildlife." (p.2) The report describes the area and discusses potential issues. It includes maps, an aerial photograph, and a species list. Title: Siletz Bay National Fish and Wildlife Refuge : environmental assessment Author: U.S. Fish and Wildlife Service. Region 1, Harrison, Ben "The Service is proposing to establish the Siletz Bay National Fish and Wildlife Refuge by initially accepting a donation of 46 acres of salt marsh, acquiring up to 793 acres of land, and cooperatively managing 1,060 acres of tidelands with the State of Oregon... The primary need for the Service acquisition is to preserve diverse coastal wetland habitats and upland buffers for a variety of waterfowl, shorebirds, marine mammals, endangered species, raptors, songbirds, anadromous and resident fish, and other wildlife." (p.2) The report describes the area and discusses potential issues. It includes maps, an aerial photograph, and a species list. Close

• 6. [Article] Multiscale relationships of wintering birds with riparian and wetland habitat in the Willamette Valley, Oregon

  Relatively little is known about wintering bird communities in lowlands of the Pacific Northwest, yet, the condition of winter habitats potentially can pose a major constraint on bird populations. I initiated ...

  Citation × Citation Citation Abstract Copy Title: Multiscale relationships of wintering birds with riparian and wetland habitat in the Willamette Valley, Oregon Author: Adamus, Paul R. Relatively little is known about wintering bird communities in lowlands of the Pacific Northwest, yet, the condition of winter habitats potentially can pose a major constraint on bird populations. I initiated a study to determine: (1) Which avian species use lowland riparian and wetland habitats in the Willamette Valley during winter, and with what intraseasonal regularity? (2) To what extent are these species associated - individually and collectively - with landscape and site-scale habitat variables? (3) To what extent are these species associated - individually and collectively - with particular landscape vs. site-scale variables? (4) How are the apparent associations affected by survey procedures and data analysis methods? Two survey procedures (area counts and point counts) in 1995 and 1996 found 104 species during 10 visits to 142 riparian and wetland sites. Area counts mainly surveyed waterbirds and raptors; point counts surveyed passerines. From area counts, mean richness ranged 0 toll species among sites and 1 to 5 species among weeks at an average site; mean number of individuals ranged 0 to 1016 among sites and from 6 to 199 among weeks at an average site. From point counts, richness ranged 1 to 6 species both among sites and among weeks at an average site. Mean number of individuals ranged 0 to 1016 per site and 6 to 199 among weeks at an average site. I individually examined 64 species to identify relative degree of association with site-scale and landscape variables. Winter Wren, Bewick's Wren, Hutton's Vireo, and Varied Thrush were significantly associated with woody cover at one or more spatial scales. Passerine abundance was greatest at sites with slowflowing water. Richness was associated with soil inundation category, peaking at intermediate frequencies and interacting with canopy cover and wooded patch extent. Richness of non-passerines was greater where standing water occupied >6% of the landscape nearest the site. Conclusions for many species and community metrics were sensitive to choice of survey methods, variables, measurement procedures, and statistical analysis tests. Ratings generated by OFWAM, a general tool for categorizing overall wetland habitat quality, did not significantly parallel measured richness and abundance of wintering birds. Title: Multiscale relationships of wintering birds with riparian and wetland habitat in the Willamette Valley, Oregon Author: Adamus, Paul R. Relatively little is known about wintering bird communities in lowlands of the Pacific Northwest, yet, the condition of winter habitats potentially can pose a major constraint on bird populations. I initiated a study to determine: (1) Which avian species use lowland riparian and wetland habitats in the Willamette Valley during winter, and with what intraseasonal regularity? (2) To what extent are these species associated - individually and collectively - with landscape and site-scale habitat variables? (3) To what extent are these species associated - individually and collectively - with particular landscape vs. site-scale variables? (4) How are the apparent associations affected by survey procedures and data analysis methods? Two survey procedures (area counts and point counts) in 1995 and 1996 found 104 species during 10 visits to 142 riparian and wetland sites. Area counts mainly surveyed waterbirds and raptors; point counts surveyed passerines. From area counts, mean richness ranged 0 toll species among sites and 1 to 5 species among weeks at an average site; mean number of individuals ranged 0 to 1016 among sites and from 6 to 199 among weeks at an average site. From point counts, richness ranged 1 to 6 species both among sites and among weeks at an average site. Mean number of individuals ranged 0 to 1016 per site and 6 to 199 among weeks at an average site. I individually examined 64 species to identify relative degree of association with site-scale and landscape variables. Winter Wren, Bewick's Wren, Hutton's Vireo, and Varied Thrush were significantly associated with woody cover at one or more spatial scales. Passerine abundance was greatest at sites with slowflowing water. Richness was associated with soil inundation category, peaking at intermediate frequencies and interacting with canopy cover and wooded patch extent. Richness of non-passerines was greater where standing water occupied >6% of the landscape nearest the site. Conclusions for many species and community metrics were sensitive to choice of survey methods, variables, measurement procedures, and statistical analysis tests. Ratings generated by OFWAM, a general tool for categorizing overall wetland habitat quality, did not significantly parallel measured richness and abundance of wintering birds. Close

• 7. [Article] The Effects of Tide Gates on Estuarine Habitats and Migratory Fish

  Citation × Citation Citation Abstract Copy Title: The Effects of Tide Gates on Estuarine Habitats and Migratory Fish Author: Souder, Jon A., Giannico, Guillermo R. Title: The Effects of Tide Gates on Estuarine Habitats and Migratory Fish Author: Souder, Jon A., Giannico, Guillermo R. Close

• 8. [Article] Hawaiian duck (Anas wyvilliana) behavior and response to wetland habitat management at Hanalei National Wildlife Refuge on Kaua'i

  The endangered Hawaiian Duck (koloa maoli; Anas wyvilliana), a non-migratory and island-endemic species, experienced a significant population decline during the twentieth century due to factors such as ...

  Citation × Citation Citation Abstract Copy Title: Hawaiian duck (Anas wyvilliana) behavior and response to wetland habitat management at Hanalei National Wildlife Refuge on Kaua'i Author: Malachowski, Christopher P. The endangered Hawaiian Duck (koloa maoli; Anas wyvilliana), a non-migratory and island-endemic species, experienced a significant population decline during the twentieth century due to factors such as habitat loss, overharvest, introduced mammalian predators, and hybridization with introduced feral Mallards (A. platyrhynchos). A key objective for Hawaiian Duck recovery is to establish a protected and managed network of wetland habitats; however, development of effective habitat management plans is stymied by the lack of information on patterns of habitat use in relation to fundamental resource requirements. Furthermore, many generalizations regarding dabbling duck behavior and resource requirements that guide seasonal wetland management objectives in North America may not apply to tropical regions and island systems. In this thesis, I compare the behavioral repertoire of the Hawaiian Duck with closely related island-endemic waterfowl and migratory North American Anas, I investigate the behavioral response of Hawaiian Ducks to wetland habitat management and taro cultivation, and I examine the effects of environmental, climatic, temporal, and social factors on the activity budgets of Hawaiian Ducks. I conducted instantaneous focal sampling (n = 984 observation sessions; 328.8 hr) throughout the annual cycle from September 2010 to August 2011 at managed wetlands and taro lo'i within Hanalei National Wildlife Refuge (NWR), Kaua'i. I documented 73 specific Hawaiian Duck behaviors in eight broad behavior categories including foraging, maintenance, resting, locomotion, alert, courtship, and intraspecific and interspecific agonistic interactions. I found that the behavioral repertoire of the Hawaiian Duck was similar to that of the Mallard; however, subtle variations in the form and linkage of certain courtship displays, such as nod-swimming, were observed. Additionally, male Hawaiian Ducks were occasionally associated with brood-rearing females (11% of brood observations), and this behavior appeared to be a male strategy whereby females received little perceived benefit , but males may have potentially garnered additional breeding attempts or maintained pair-bonds for subsequent breeding seasons. After accounting for sex, pair status, month, and time of day, the diurnal behavioral activities of Hawaiian Ducks differed between managed wetlands and taro habitats (F₆,₉₆₀ = 30.3, P < 0.001). Hawaiian Ducks utilized taro predominantly for resting (44%), maintenance (21%), and foraging (15%), while birds used managed wetlands for a variety of activities, including foraging (11%), maintenance (28%), resting (27%), and locomotion (22%). Social activities, particularly courtship, occurred more frequently in managed wetlands than in taro (H₁ = 11.9, P < 0.001). In managed wetlands, birds foraged slightly more with increasing cover of Cyperus spp. (r = 0.18, P < 0.001) and Fimbristylis littoralis (r = 0.17, P < 0.01) and decreasing cover of Urochloa mutica (r = -0.15, P < 0.01) and wetland vegetation height (r = -0.22, P < 0.001). Within taro habitat, the behavioral activities of Hawaiian Ducks differed significantly between birds in lo'i and on dikes (F₆,₄₆₈ = 142.8, P < 0.001); birds utilized lo‘i dikes for resting (60%) and maintenance activities (21%), whereas birds entered lo‘i primarily to forage (45%). The activity budget of Hawaiian Ducks was strongly influenced by time of day (F₁₈,₂₇₁₅.₇₈ = 6.4, P < 0.001), and birds spent more time engaged in active behaviors (i.e., foraging, locomotion, and alert) and less time resting during early morning and evening than during late morning and afternoon. While strong seasonal shifts in most behavioral patterns were not detected, males allocated more time to courting (1.1 vs. 0.3%; H1 = 6.92, P = 0.009) and mate-guarding (0.5 vs. <0.1%; H₁ = 9.83, P = 0.002) in managed wetlands between November and March than the remainder of the year. The effects of sex (F₆,₉₆₀ = 6.06, P < 0.001) and social status (F₆,₆₈₂ = 6.69, P < 0.001) on activity budgets were also significant. Females spent more time foraging (18 vs. 12%) and less time in alert, locomotor, and social behaviors than males. Paired birds allocated more time to aggression towards conspecifics, mate-guarding, and courtship, and within taro lo‘i, paired birds foraged more and rested less than unpaired birds. Overall, Hawaiian Duck allocated diurnal activity budgets differently in managed and cultivated wetland habitat at Hanalei NWR, suggesting that both systems may play an important role in fulfilling fundamental daily and seasonal resource requirements. The increased range of activities and foraging tactics used in managed wetlands may indicate the greater habitat diversity (e.g., vegetation structure, patchiness, plant species richness, range of water depths) provided by seasonal wetlands. In general, Hawaiian Duck allocated less time to diurnal foraging than North American Anas, such Mallard and Mottled Duck (A. fulvigula), suggesting that Hawaiian Duck may have lower daily and seasonal energy demands, have access to higher quality diet, or allot more time to nocturnal foraging activities. Also, unlike many North American migratory waterfowl that demonstrate significant behavioral plasticity in adjusting activity budgets to meet seasonal energy demands associated with breeding, molting, wintering, and migration, Hawaiian Duck did not exhibit a strong seasonal shift in most behaviors which may reflect their non-migratory nature and asynchronous life history cycle. Title: Hawaiian duck (Anas wyvilliana) behavior and response to wetland habitat management at Hanalei National Wildlife Refuge on Kaua'i Author: Malachowski, Christopher P. The endangered Hawaiian Duck (koloa maoli; Anas wyvilliana), a non-migratory and island-endemic species, experienced a significant population decline during the twentieth century due to factors such as habitat loss, overharvest, introduced mammalian predators, and hybridization with introduced feral Mallards (A. platyrhynchos). A key objective for Hawaiian Duck recovery is to establish a protected and managed network of wetland habitats; however, development of effective habitat management plans is stymied by the lack of information on patterns of habitat use in relation to fundamental resource requirements. Furthermore, many generalizations regarding dabbling duck behavior and resource requirements that guide seasonal wetland management objectives in North America may not apply to tropical regions and island systems. In this thesis, I compare the behavioral repertoire of the Hawaiian Duck with closely related island-endemic waterfowl and migratory North American Anas, I investigate the behavioral response of Hawaiian Ducks to wetland habitat management and taro cultivation, and I examine the effects of environmental, climatic, temporal, and social factors on the activity budgets of Hawaiian Ducks. I conducted instantaneous focal sampling (n = 984 observation sessions; 328.8 hr) throughout the annual cycle from September 2010 to August 2011 at managed wetlands and taro lo'i within Hanalei National Wildlife Refuge (NWR), Kaua'i. I documented 73 specific Hawaiian Duck behaviors in eight broad behavior categories including foraging, maintenance, resting, locomotion, alert, courtship, and intraspecific and interspecific agonistic interactions. I found that the behavioral repertoire of the Hawaiian Duck was similar to that of the Mallard; however, subtle variations in the form and linkage of certain courtship displays, such as nod-swimming, were observed. Additionally, male Hawaiian Ducks were occasionally associated with brood-rearing females (11% of brood observations), and this behavior appeared to be a male strategy whereby females received little perceived benefit , but males may have potentially garnered additional breeding attempts or maintained pair-bonds for subsequent breeding seasons. After accounting for sex, pair status, month, and time of day, the diurnal behavioral activities of Hawaiian Ducks differed between managed wetlands and taro habitats (F₆,₉₆₀ = 30.3, P < 0.001). Hawaiian Ducks utilized taro predominantly for resting (44%), maintenance (21%), and foraging (15%), while birds used managed wetlands for a variety of activities, including foraging (11%), maintenance (28%), resting (27%), and locomotion (22%). Social activities, particularly courtship, occurred more frequently in managed wetlands than in taro (H₁ = 11.9, P < 0.001). In managed wetlands, birds foraged slightly more with increasing cover of Cyperus spp. (r = 0.18, P < 0.001) and Fimbristylis littoralis (r = 0.17, P < 0.01) and decreasing cover of Urochloa mutica (r = -0.15, P < 0.01) and wetland vegetation height (r = -0.22, P < 0.001). Within taro habitat, the behavioral activities of Hawaiian Ducks differed significantly between birds in lo'i and on dikes (F₆,₄₆₈ = 142.8, P < 0.001); birds utilized lo‘i dikes for resting (60%) and maintenance activities (21%), whereas birds entered lo‘i primarily to forage (45%). The activity budget of Hawaiian Ducks was strongly influenced by time of day (F₁₈,₂₇₁₅.₇₈ = 6.4, P < 0.001), and birds spent more time engaged in active behaviors (i.e., foraging, locomotion, and alert) and less time resting during early morning and evening than during late morning and afternoon. While strong seasonal shifts in most behavioral patterns were not detected, males allocated more time to courting (1.1 vs. 0.3%; H1 = 6.92, P = 0.009) and mate-guarding (0.5 vs. <0.1%; H₁ = 9.83, P = 0.002) in managed wetlands between November and March than the remainder of the year. The effects of sex (F₆,₉₆₀ = 6.06, P < 0.001) and social status (F₆,₆₈₂ = 6.69, P < 0.001) on activity budgets were also significant. Females spent more time foraging (18 vs. 12%) and less time in alert, locomotor, and social behaviors than males. Paired birds allocated more time to aggression towards conspecifics, mate-guarding, and courtship, and within taro lo‘i, paired birds foraged more and rested less than unpaired birds. Overall, Hawaiian Duck allocated diurnal activity budgets differently in managed and cultivated wetland habitat at Hanalei NWR, suggesting that both systems may play an important role in fulfilling fundamental daily and seasonal resource requirements. The increased range of activities and foraging tactics used in managed wetlands may indicate the greater habitat diversity (e.g., vegetation structure, patchiness, plant species richness, range of water depths) provided by seasonal wetlands. In general, Hawaiian Duck allocated less time to diurnal foraging than North American Anas, such Mallard and Mottled Duck (A. fulvigula), suggesting that Hawaiian Duck may have lower daily and seasonal energy demands, have access to higher quality diet, or allot more time to nocturnal foraging activities. Also, unlike many North American migratory waterfowl that demonstrate significant behavioral plasticity in adjusting activity budgets to meet seasonal energy demands associated with breeding, molting, wintering, and migration, Hawaiian Duck did not exhibit a strong seasonal shift in most behaviors which may reflect their non-migratory nature and asynchronous life history cycle. Close

• 9. [Article] Habitat associations and life histories of odonata in riverine wetlands of the Willamette Valley, Oregon

  This thesis explored the distributions and life histories of dragonflies and damselflies (Insecta: Odonata) of the riverine wetlands of the Willamette Valley in western Oregon, USA. Odonate species distributions ...

  Citation × Citation Citation Abstract Copy Title: Habitat associations and life histories of odonata in riverine wetlands of the Willamette Valley, Oregon Author: Beatty, Christopher D. This thesis explored the distributions and life histories of dragonflies and damselflies (Insecta: Odonata) of the riverine wetlands of the Willamette Valley in western Oregon, USA. Odonate species distributions were characterized over two seasons in the autumn of 2000 and the spring of 2001-at twenty-seven wetlands located throughout the valley. Distributions of nymphs and adults were compared with wetland habitat conditions that may affect odonate diversity. Odonate nymph and adult distributions were analyzed through Hierarchical Agglomerative cluster analysis (HA). HA identified discrete clusters of sites based on the distributions of species in the genera Aeshna, Erythemis, Lestes, Libellula, Pachydiplax, Sympetrum and Tramea. To identify habitat associations with odonate species, nymph and adult data were analyzed by Non-metric Multidimensional Scaling (NMS). NMS revealed that odonate distributions are associated with site hydrology, water depth and temperature, the presence of large emergent plants (e.g. Typha latifolia), the presence of fish, and surrounding landcover. These data will provide guidance for wetland managers in the use of odonates as indicators of wetland health. To further examine the relationship between odonate species and their wetland habitats, quantitative life history data for the 27 odonate species were analyzed to determine functional associations between species attributes and the environments in which they are found. Oviposition location, presence of a resting egg, over-wintering life stage, nymphal foraging strategy and adult flight season were subjected to NMS, to determine biological similarities between species occupying particular locations. Life history patterns correlated strongly with hydrology. Analysis of sites by odonate species ricimess found a relationship between richness and site hydrology, but failed to explain the distribution of several species associated with wetlands that dry during part of the year. We conclude from our results that species-level life history data are essential for explaining odonate distributions. We determined that the presence of odonate species in a wetland is indicative of habitat condition, that analysis of odonate distributions at the species level is necessary to understand habitat associations, and that analysis of life-history attributes provides a functional understanding of odonate distributions that measurements of species richness or the distributions of generaor families alone cannot explain. Title: Habitat associations and life histories of odonata in riverine wetlands of the Willamette Valley, Oregon Author: Beatty, Christopher D. This thesis explored the distributions and life histories of dragonflies and damselflies (Insecta: Odonata) of the riverine wetlands of the Willamette Valley in western Oregon, USA. Odonate species distributions were characterized over two seasons in the autumn of 2000 and the spring of 2001-at twenty-seven wetlands located throughout the valley. Distributions of nymphs and adults were compared with wetland habitat conditions that may affect odonate diversity. Odonate nymph and adult distributions were analyzed through Hierarchical Agglomerative cluster analysis (HA). HA identified discrete clusters of sites based on the distributions of species in the genera Aeshna, Erythemis, Lestes, Libellula, Pachydiplax, Sympetrum and Tramea. To identify habitat associations with odonate species, nymph and adult data were analyzed by Non-metric Multidimensional Scaling (NMS). NMS revealed that odonate distributions are associated with site hydrology, water depth and temperature, the presence of large emergent plants (e.g. Typha latifolia), the presence of fish, and surrounding landcover. These data will provide guidance for wetland managers in the use of odonates as indicators of wetland health. To further examine the relationship between odonate species and their wetland habitats, quantitative life history data for the 27 odonate species were analyzed to determine functional associations between species attributes and the environments in which they are found. Oviposition location, presence of a resting egg, over-wintering life stage, nymphal foraging strategy and adult flight season were subjected to NMS, to determine biological similarities between species occupying particular locations. Life history patterns correlated strongly with hydrology. Analysis of sites by odonate species ricimess found a relationship between richness and site hydrology, but failed to explain the distribution of several species associated with wetlands that dry during part of the year. We conclude from our results that species-level life history data are essential for explaining odonate distributions. We determined that the presence of odonate species in a wetland is indicative of habitat condition, that analysis of odonate distributions at the species level is necessary to understand habitat associations, and that analysis of life-history attributes provides a functional understanding of odonate distributions that measurements of species richness or the distributions of generaor families alone cannot explain. Close

• 10. [Article] Sauvie Island north unit wetlands project : biological opinion

  The objective of this Biological Opinion (BO) is to determine whether the action to restore emergent vegetation to wetlands on Sauvie Island is likely to jeopardize the continued existence of Upper Willamette ...

  Citation × Citation Citation Abstract Copy Title: Sauvie Island north unit wetlands project : biological opinion The objective of this Biological Opinion (BO) is to determine whether the action to restore emergent vegetation to wetlands on Sauvie Island is likely to jeopardize the continued existence of Upper Willamette River chinook salmon and Lower Columbia river chinook salmon or destroy, or adversely modify proposed critical habitat. Title: Sauvie Island north unit wetlands project : biological opinion The objective of this Biological Opinion (BO) is to determine whether the action to restore emergent vegetation to wetlands on Sauvie Island is likely to jeopardize the continued existence of Upper Willamette River chinook salmon and Lower Columbia river chinook salmon or destroy, or adversely modify proposed critical habitat. Close