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• 11. [Article] Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon

  The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed ...

  Citation × Citation Citation Abstract Copy Title: Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon Author: Foster, Susan Ann Year: 1992 The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed subspecies of western gray squirrel (S. griseus) were conducted at three sites in the ponderosa pine-Oregon white oak zone on the eastern slopes of Mt. Hood, Wasco County, Oregon, between 1981 and 1989. From 1981 through 1987, a Hunter Cooperation Program provided remains of squirrels shot during the annual late summer-early autumn hunting season. Other data were gathered through capture and release studies, radiotelemetry, and habitat analysis. The age structure of these populations, as revealed by examination of squirrels killed by hunters, is predominantly mature animals. Also, the population as estimated by hunter success during the Hunter Cooperation Program and by field observations appears to be declining. In the sites studied, western gray squirrels have two seasons of reproductive activity annually. Some individuals mate from January through March; their young emerge from the nest in May and June. Other individuals mate during May and June; their young emerge in August and September. The latter matings are usually the most productive. Analysis of nest trees and their surroundings revealed that nests are most likely to be located in mature trees that have well-developed crowns and occur in stands with a high degree of canopy closure. Nest trees were usually located within approximately 180 meters of permanent water and on sites with a south-southeasterly exposure. Home ranges of squirrels examined in this study were usually large compared to home ranges reported for this species elsewhere in its range. Given the cost of having large home ranges, it seems possible that the squirrels at these study sites exist in less than optimal ecological circumstances. Human factors that may have contributed to the decline of the populations in this study may include the nature of logging activities and the timing of the annual hunting season. Limiting factors other than human activities may include competition with other mast-consuming animals (mule deer, elk, wild turkeys, and three other species of squirrels) for limited and variable mast crops. Title: Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon Author: Foster, Susan Ann Year: 1992 The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed subspecies of western gray squirrel (S. griseus) were conducted at three sites in the ponderosa pine-Oregon white oak zone on the eastern slopes of Mt. Hood, Wasco County, Oregon, between 1981 and 1989. From 1981 through 1987, a Hunter Cooperation Program provided remains of squirrels shot during the annual late summer-early autumn hunting season. Other data were gathered through capture and release studies, radiotelemetry, and habitat analysis. The age structure of these populations, as revealed by examination of squirrels killed by hunters, is predominantly mature animals. Also, the population as estimated by hunter success during the Hunter Cooperation Program and by field observations appears to be declining. In the sites studied, western gray squirrels have two seasons of reproductive activity annually. Some individuals mate from January through March; their young emerge from the nest in May and June. Other individuals mate during May and June; their young emerge in August and September. The latter matings are usually the most productive. Analysis of nest trees and their surroundings revealed that nests are most likely to be located in mature trees that have well-developed crowns and occur in stands with a high degree of canopy closure. Nest trees were usually located within approximately 180 meters of permanent water and on sites with a south-southeasterly exposure. Home ranges of squirrels examined in this study were usually large compared to home ranges reported for this species elsewhere in its range. Given the cost of having large home ranges, it seems possible that the squirrels at these study sites exist in less than optimal ecological circumstances. Human factors that may have contributed to the decline of the populations in this study may include the nature of logging activities and the timing of the annual hunting season. Limiting factors other than human activities may include competition with other mast-consuming animals (mule deer, elk, wild turkeys, and three other species of squirrels) for limited and variable mast crops. Close

• 12. [Article] Impacts of Predicted Global Sea-Level Rise on Oregon Beaches and Tidelands

  Forward by: Phillip Johnson, Executive Director Oregon Shores Conservation Coalition The Oregon Shores Conservation Coalition’s "Coastal Climate Change Adaptation Project" is under development as an experiment ...

  Citation × Citation Citation Abstract Copy Title: Impacts of Predicted Global Sea-Level Rise on Oregon Beaches and Tidelands Author: Peterson, Curt D. Year: 2013 Forward by: Phillip Johnson, Executive Director Oregon Shores Conservation Coalition The Oregon Shores Conservation Coalition’s "Coastal Climate Change Adaptation Project" is under development as an experiment in grassroots organizing for adaptive planning for expected climate change impacts. Oregon Shores is a regional conservation group with a 40-year history of working to protect marine, shoreline, estuarine and other coastal habitats. The organization’s board and staff came to recognize that the likely effects of climate change—rising sea levels, more intensive storm surges, increased erosion, lower-river flooding, among others—would affect every aspect of the group’s work. Consequently, a new program, the Climate Action Program, was created to address the need for long-range adaptive planning to preserve the resilience of communities, both human and natural. Oregon Shores’ premise in developing the Coastal Climate Change Adaptation Project is that for adaptive planning to be meaningful, broad community acceptance and support are necessary. The project is thus designed as a grassroots effort, with the aim of developing broad support before any proposal should be submitted to local governments. Title: Impacts of Predicted Global Sea-Level Rise on Oregon Beaches and Tidelands Author: Peterson, Curt D. Year: 2013 Forward by: Phillip Johnson, Executive Director Oregon Shores Conservation Coalition The Oregon Shores Conservation Coalition’s "Coastal Climate Change Adaptation Project" is under development as an experiment in grassroots organizing for adaptive planning for expected climate change impacts. Oregon Shores is a regional conservation group with a 40-year history of working to protect marine, shoreline, estuarine and other coastal habitats. The organization’s board and staff came to recognize that the likely effects of climate change—rising sea levels, more intensive storm surges, increased erosion, lower-river flooding, among others—would affect every aspect of the group’s work. Consequently, a new program, the Climate Action Program, was created to address the need for long-range adaptive planning to preserve the resilience of communities, both human and natural. Oregon Shores’ premise in developing the Coastal Climate Change Adaptation Project is that for adaptive planning to be meaningful, broad community acceptance and support are necessary. The project is thus designed as a grassroots effort, with the aim of developing broad support before any proposal should be submitted to local governments. Close

• 13. [Article] Climate Change, Its Effect on Migration Patterns of the Cackling Goose and White-Fronted Goose in the Willamette Valley, and Implications for Goose Management

  This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted ...

  Citation × Citation Citation Abstract Copy Title: Climate Change, Its Effect on Migration Patterns of the Cackling Goose and White-Fronted Goose in the Willamette Valley, and Implications for Goose Management Author: Warren, Kelly Year: 2010 This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted geese (Anser albifrons frontalis). Ancillary questions that are considered are as follows: • If global warming is affecting these species, what is the nature of the effects? • How are the changes affecting the human environment and what can be done about these effects? In 1994, the majority of the cackler population in the Pacific Flyway began to winter in Oregon’s Willamette Valley rather than in their historical wintering areas in California’s Central Valley. In recent years, the Pacific white-fronted goose has shown a change in behavior similar to that of cacklers just before their major shift. The reasons for this shift have not been clear, though climate change, agricultural shifts, or competition with other species were thought to be possible causes. Analyses of historical breeding and wintering surveys, bird band data, harvest data, agricultural data, and climate and weather data were undertaken in the course of this thesis to see if the cause or causes could be identified. The results showed that climate and weather data, i.e. an increase in average annual temperature coupled with occasional severe winters, most closely correlated with the cacklers’ shift northward. The data comparison revealed that there is a direct relationship between cacklers and a warming shift seen on the wintering grounds. There also was a secondary correlation between the northward shift and recent changes in agricultural crops in the Willamette Valley. Substantially less data are available for white-fronts, and the relationship between their recent migration changes and climate and/or other factors is much less clear. The following recommendations for management and further study are aimed at more completely understanding the scope and causes of migration shifts and formulating well-founded management plans for geese in the Pacific Flyway: • Continue research to determine if climate change is causing changes in goose population numbers and behavior. • Expand breeding ground flight surveys to include cacklers and habitat preference to learn how habitat change on the Y-K Delta is altering cackler behavior and breeding success. • Expand radio transmitter studies and collar programs for cacklers in Oregon and Washington to verify northerly wintering shifts. • Expand collar programs for cacklers wintering in the Willamette Valley to determine if the population is continuing to shift northward. • Expand banding programs for white-fronted geese to gather more data about migration patterns. • Develop models that will allow researchers and managers to correlate migration behavior with various environmental factors including climate change in order to: 1) determine which factors are causing migration changes in specific waterfowl populations and 2) allow managers to make changes to management plans in advance of rapid changes. • Inform the public about how it can assist in collar surveys or volunteer for the U.S. Fish and Wildlife Service (USFWS). This will enable USFWS to have more concrete data and give the public an opportunity gain a greater understanding of geese and goose management. • Expand research on urban cackling geese to determine the nature and scope of their effect on the human environment and to devise management strategies. • Research energetics in migrating geese to determine whether the shift in migration patterns has its basis in climate change. • Increase data exchange and coordination among agencies. • Formulate and implement plans at the city and county levels to manage growing numbers of geese in urban areas. • Recognize and anticipate the possibility that goose populations may move into new wintering areas and formulate plans for management of those species. • Implement low cost techniques, such as more liberal bag limits and seasons, hazing, etc., to assist agricultural landowners in decreasing goose-related crop damage. Title: Climate Change, Its Effect on Migration Patterns of the Cackling Goose and White-Fronted Goose in the Willamette Valley, and Implications for Goose Management Author: Warren, Kelly Year: 2010 This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted geese (Anser albifrons frontalis). Ancillary questions that are considered are as follows: • If global warming is affecting these species, what is the nature of the effects? • How are the changes affecting the human environment and what can be done about these effects? In 1994, the majority of the cackler population in the Pacific Flyway began to winter in Oregon’s Willamette Valley rather than in their historical wintering areas in California’s Central Valley. In recent years, the Pacific white-fronted goose has shown a change in behavior similar to that of cacklers just before their major shift. The reasons for this shift have not been clear, though climate change, agricultural shifts, or competition with other species were thought to be possible causes. Analyses of historical breeding and wintering surveys, bird band data, harvest data, agricultural data, and climate and weather data were undertaken in the course of this thesis to see if the cause or causes could be identified. The results showed that climate and weather data, i.e. an increase in average annual temperature coupled with occasional severe winters, most closely correlated with the cacklers’ shift northward. The data comparison revealed that there is a direct relationship between cacklers and a warming shift seen on the wintering grounds. There also was a secondary correlation between the northward shift and recent changes in agricultural crops in the Willamette Valley. Substantially less data are available for white-fronts, and the relationship between their recent migration changes and climate and/or other factors is much less clear. The following recommendations for management and further study are aimed at more completely understanding the scope and causes of migration shifts and formulating well-founded management plans for geese in the Pacific Flyway: • Continue research to determine if climate change is causing changes in goose population numbers and behavior. • Expand breeding ground flight surveys to include cacklers and habitat preference to learn how habitat change on the Y-K Delta is altering cackler behavior and breeding success. • Expand radio transmitter studies and collar programs for cacklers in Oregon and Washington to verify northerly wintering shifts. • Expand collar programs for cacklers wintering in the Willamette Valley to determine if the population is continuing to shift northward. • Expand banding programs for white-fronted geese to gather more data about migration patterns. • Develop models that will allow researchers and managers to correlate migration behavior with various environmental factors including climate change in order to: 1) determine which factors are causing migration changes in specific waterfowl populations and 2) allow managers to make changes to management plans in advance of rapid changes. • Inform the public about how it can assist in collar surveys or volunteer for the U.S. Fish and Wildlife Service (USFWS). This will enable USFWS to have more concrete data and give the public an opportunity gain a greater understanding of geese and goose management. • Expand research on urban cackling geese to determine the nature and scope of their effect on the human environment and to devise management strategies. • Research energetics in migrating geese to determine whether the shift in migration patterns has its basis in climate change. • Increase data exchange and coordination among agencies. • Formulate and implement plans at the city and county levels to manage growing numbers of geese in urban areas. • Recognize and anticipate the possibility that goose populations may move into new wintering areas and formulate plans for management of those species. • Implement low cost techniques, such as more liberal bag limits and seasons, hazing, etc., to assist agricultural landowners in decreasing goose-related crop damage. Close