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• 1. [Article] Modeling Predator Habitat to Enhance Reintroduction Planning

  Context The success of species reintroduction often depends on predation risk and spatial estimates of predator habitat. The fisher (Pekania pennanti) is a species of conservation concern and populations ...

  Citation × Citation Citation Abstract Copy Title: Modeling Predator Habitat to Enhance Reintroduction Planning Author: Halsey, Shiloh Michael, Zielinski, William J., Scheller, Robert M. Year: 2015 Context The success of species reintroduction often depends on predation risk and spatial estimates of predator habitat. The fisher (Pekania pennanti) is a species of conservation concern and populations in the western United States have declined substantially in the last century. Reintroduction plans are underway, but the ability of the species to establish a selfsustaining population is affected by predation from its primary predator, the bobcat (Lynx rufus). Objectives To develop a habitat model that incorporates both habitat of the focal species and the spatial patterning of predator habitat. To locate areas of densely aggregated habitat that would be suitable for reintroduction. Methods Using camera survey data, we modeled the association between bobcat presence and environmental features using a classification tree. We applied this model to a spatial analysis of fisher habitat and identified reintroduction areas in the southern Washington Cascade Range. Results The classification tree predicted bobcat detection based on elevation and mean tree diameter. The final model identified fisher reintroduction locations primarily in or near existing wilderness areas. Fisher habitat areas identified considering both habitat and predation risk differed from those identified without considering predation. Conclusion Our spatial approach is unique among fisher reintroduction plans by accounting for both resource requirements and risk of predation. It can be used as a template for future reintroduction efforts in other regions and for other species. Using similar models to refine population management and reintroduction should improve the probability of successful population establishment and stability. Title: Modeling Predator Habitat to Enhance Reintroduction Planning Author: Halsey, Shiloh Michael, Zielinski, William J., Scheller, Robert M. Year: 2015 Context The success of species reintroduction often depends on predation risk and spatial estimates of predator habitat. The fisher (Pekania pennanti) is a species of conservation concern and populations in the western United States have declined substantially in the last century. Reintroduction plans are underway, but the ability of the species to establish a selfsustaining population is affected by predation from its primary predator, the bobcat (Lynx rufus). Objectives To develop a habitat model that incorporates both habitat of the focal species and the spatial patterning of predator habitat. To locate areas of densely aggregated habitat that would be suitable for reintroduction. Methods Using camera survey data, we modeled the association between bobcat presence and environmental features using a classification tree. We applied this model to a spatial analysis of fisher habitat and identified reintroduction areas in the southern Washington Cascade Range. Results The classification tree predicted bobcat detection based on elevation and mean tree diameter. The final model identified fisher reintroduction locations primarily in or near existing wilderness areas. Fisher habitat areas identified considering both habitat and predation risk differed from those identified without considering predation. Conclusion Our spatial approach is unique among fisher reintroduction plans by accounting for both resource requirements and risk of predation. It can be used as a template for future reintroduction efforts in other regions and for other species. Using similar models to refine population management and reintroduction should improve the probability of successful population establishment and stability. Close

• 2. [Article] Aquatic Plant Surveys in the Bureau of Land Management, Medford District, 2010-2011

  The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. ...

  Citation × Citation Citation Abstract Copy Title: Aquatic Plant Surveys in the Bureau of Land Management, Medford District, 2010-2011 Author: Sytsma, Mark D., Miller, Rich, Morgan, Vanessa Year: 2011 The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. Early detection of new invasions can improve chances for successful eradication or containment to reduce the risk of IAPS spread. The Oregon Department of Agriculture (ODA) lists the most egregious offenders as “Noxious Weeds” which are defined as plants classified by the Oregon State Weed Board that are injurious to public health, agriculture, recreation, wildlife, or any public or private property (ODA 2011). Several IAPS classified as noxious have been detected within the Medford District of the Bureau of Land Management (BLM) in Southern Oregon including yellow floating heart (Nymphoides peltata) and yellow flag iris (Iris pseudacorus). During the summers of 2010 and 2011, IAPS surveys were conducted at selected reservoirs, lakes, and river boat launches within the Medford District to determine the extent of IAPS infestations as well as the distributions of native aquatic plant species. This report summarizes results of the surveys and provides recommendations for management of IAPS within the Medford District. Observations of any invasive aquatic animal species such as New Zealand mudsnails (Potamopyrgus antipodarum) are also reported. Title: Aquatic Plant Surveys in the Bureau of Land Management, Medford District, 2010-2011 Author: Sytsma, Mark D., Miller, Rich, Morgan, Vanessa Year: 2011 The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. Early detection of new invasions can improve chances for successful eradication or containment to reduce the risk of IAPS spread. The Oregon Department of Agriculture (ODA) lists the most egregious offenders as “Noxious Weeds” which are defined as plants classified by the Oregon State Weed Board that are injurious to public health, agriculture, recreation, wildlife, or any public or private property (ODA 2011). Several IAPS classified as noxious have been detected within the Medford District of the Bureau of Land Management (BLM) in Southern Oregon including yellow floating heart (Nymphoides peltata) and yellow flag iris (Iris pseudacorus). During the summers of 2010 and 2011, IAPS surveys were conducted at selected reservoirs, lakes, and river boat launches within the Medford District to determine the extent of IAPS infestations as well as the distributions of native aquatic plant species. This report summarizes results of the surveys and provides recommendations for management of IAPS within the Medford District. Observations of any invasive aquatic animal species such as New Zealand mudsnails (Potamopyrgus antipodarum) are also reported. Close

• 3. [Article] Divergent Carbon Dynamics under Climate Change in Forests with Diverse Soils, Tree Species, and Land Use Histories

  Accounting for both climate change and natural disturbances—which typically result in greenhouse gas emissions—is necessary to begin managing forest carbon sequestration. Gaining a complete understanding ...

  Citation × Citation Citation Abstract Copy Title: Divergent Carbon Dynamics under Climate Change in Forests with Diverse Soils, Tree Species, and Land Use Histories Author: Scheller, Robert M., Kretchun, Alec M., Van Tuyl, Steve, Clark, Kenneth L., Lucash, Melissa S., Hom, John Year: 2012 Accounting for both climate change and natural disturbances—which typically result in greenhouse gas emissions—is necessary to begin managing forest carbon sequestration. Gaining a complete understanding of forest carbon dynamics is, however, challenging in systems characterized by historic over-utilization, diverse soils and tree species, and frequent disturbance. In order to elucidate the cascading effects of potential climate change on such systems, we projected forest carbon dynamics, including soil carbon changes, and shifts in tree species composition as a consequence of wildfires and climate change in the New Jersey pine barrens (NJPB) over the next 100 years. To do so, we used the LANDIS-II succession and disturbance model combined with the CENTURY soil model. The model was calibrated and validated using data from three eddy flux towers and the available empirical or literature data. Our results suggest that climate change will not appreciably increase fire sizes and intensity. The recovery of C stocks following substantial disturbances at the turn of the 20th century will play a limited but important role in this system. In areas characterized by high soil water holding capacity, reduced soil moisture may lead to lower total C and these forests may switch from being carbon sinks to becoming carbon neutral towards the latter part of the 21st century. In contrast, other areas characterized by lower soil water holding capacity and drought tolerant species are projected to experience relatively little change over the next 100 years. Across all soil types, however, the regeneration of many key tree species may decline leading to longer-term (beyond 2100) risks to forest C. These divergent responses were largely a function of the dominant tree species, and their respective temperature and soil moisture tolerances, and soil water holding capacity. In summary, the system is initially C conservative but by the end of the 21st century, there is increasing risk of de-stabilization due to declining growth and regeneration. Title: Divergent Carbon Dynamics under Climate Change in Forests with Diverse Soils, Tree Species, and Land Use Histories Author: Scheller, Robert M., Kretchun, Alec M., Van Tuyl, Steve, Clark, Kenneth L., Lucash, Melissa S., Hom, John Year: 2012 Accounting for both climate change and natural disturbances—which typically result in greenhouse gas emissions—is necessary to begin managing forest carbon sequestration. Gaining a complete understanding of forest carbon dynamics is, however, challenging in systems characterized by historic over-utilization, diverse soils and tree species, and frequent disturbance. In order to elucidate the cascading effects of potential climate change on such systems, we projected forest carbon dynamics, including soil carbon changes, and shifts in tree species composition as a consequence of wildfires and climate change in the New Jersey pine barrens (NJPB) over the next 100 years. To do so, we used the LANDIS-II succession and disturbance model combined with the CENTURY soil model. The model was calibrated and validated using data from three eddy flux towers and the available empirical or literature data. Our results suggest that climate change will not appreciably increase fire sizes and intensity. The recovery of C stocks following substantial disturbances at the turn of the 20th century will play a limited but important role in this system. In areas characterized by high soil water holding capacity, reduced soil moisture may lead to lower total C and these forests may switch from being carbon sinks to becoming carbon neutral towards the latter part of the 21st century. In contrast, other areas characterized by lower soil water holding capacity and drought tolerant species are projected to experience relatively little change over the next 100 years. Across all soil types, however, the regeneration of many key tree species may decline leading to longer-term (beyond 2100) risks to forest C. These divergent responses were largely a function of the dominant tree species, and their respective temperature and soil moisture tolerances, and soil water holding capacity. In summary, the system is initially C conservative but by the end of the 21st century, there is increasing risk of de-stabilization due to declining growth and regeneration. Close

• 4. [Article] OSMB Final Report: Task 5. Zebra and Quagga Mussel Early-Detection Monitoring in High Risk Oregon Waters

  Neither zebra nor quagga mussels (Dreissena polymorpha and D. rostriformis bugensis, respectively) were detected by Portland State University (PSU) during their early detection sampling in Oregon water ...

  Citation × Citation Citation Abstract Copy Title: OSMB Final Report: Task 5. Zebra and Quagga Mussel Early-Detection Monitoring in High Risk Oregon Waters Author: Wells, Steve W., Sytsma, Mark Year: 2014 Neither zebra nor quagga mussels (Dreissena polymorpha and D. rostriformis bugensis, respectively) were detected by Portland State University (PSU) during their early detection sampling in Oregon water bodies during 2013. PSU conducted sampling for planktonic larvae, juvenile, and adult mussels at nine Oregon water bodies during the July to August period coinciding with water temperatures favorable for mussel spawning. A total of 113 plankton samples were collected and over 1.6 million liters of lake water were filtered through 63-μm mesh nets during plankton sample collection. The greatest sampling effort occurred in East Lake, Prineville Reservoir, and Paulina Lake; these water bodies were identified as high risk for both mussel establishment and introduction according to Wells et al. (2009). The sampling effort, however, was fairly uniform amongst the targeted water bodies, and sampling also occurred in Upper Klamath Lake, Howard Prairie Lake, Hyatt Reservoir, Emigrant Lake, Ochoco Reservoir, and Lake Billy Chinook. Non-native invertebrates and macrophytes were opportunistically collected during Dreissena spp. sampling in 2013. Corbicula fluminea (Asian clam) straight-hinge juveniles were collected in plankton samples from East Lake and Howard Prairie Lake. Potamopyrgus antipodarum (New Zealand mud snails) were collected in Lake Billy Chinook. Radix auricularia (big-ear radix) snails were collected in Hyatt Reservoir, Lake Billy Chinook and Paulina Lake. Orconectes neglectus (ringed crayfish) were collected in Hyatt Reservoir. Potamogeton crispus (curly leaf pondweed) were collected in Howard Prairie Lake, Hyatt Reservoir, Lake Billy Chinook, and Upper Klamath Lake. Most of these collections were not the first detections for these species in these locations; however, to the authors’ knowledge, the following represent first detections: R. auricularia in Hyatt Reservoir and Paulina Lake, O. neglectus in Hyatt Reservoir and C. fluminea in Howard Prairie Lake. Title: OSMB Final Report: Task 5. Zebra and Quagga Mussel Early-Detection Monitoring in High Risk Oregon Waters Author: Wells, Steve W., Sytsma, Mark Year: 2014 Neither zebra nor quagga mussels (Dreissena polymorpha and D. rostriformis bugensis, respectively) were detected by Portland State University (PSU) during their early detection sampling in Oregon water bodies during 2013. PSU conducted sampling for planktonic larvae, juvenile, and adult mussels at nine Oregon water bodies during the July to August period coinciding with water temperatures favorable for mussel spawning. A total of 113 plankton samples were collected and over 1.6 million liters of lake water were filtered through 63-μm mesh nets during plankton sample collection. The greatest sampling effort occurred in East Lake, Prineville Reservoir, and Paulina Lake; these water bodies were identified as high risk for both mussel establishment and introduction according to Wells et al. (2009). The sampling effort, however, was fairly uniform amongst the targeted water bodies, and sampling also occurred in Upper Klamath Lake, Howard Prairie Lake, Hyatt Reservoir, Emigrant Lake, Ochoco Reservoir, and Lake Billy Chinook. Non-native invertebrates and macrophytes were opportunistically collected during Dreissena spp. sampling in 2013. Corbicula fluminea (Asian clam) straight-hinge juveniles were collected in plankton samples from East Lake and Howard Prairie Lake. Potamopyrgus antipodarum (New Zealand mud snails) were collected in Lake Billy Chinook. Radix auricularia (big-ear radix) snails were collected in Hyatt Reservoir, Lake Billy Chinook and Paulina Lake. Orconectes neglectus (ringed crayfish) were collected in Hyatt Reservoir. Potamogeton crispus (curly leaf pondweed) were collected in Howard Prairie Lake, Hyatt Reservoir, Lake Billy Chinook, and Upper Klamath Lake. Most of these collections were not the first detections for these species in these locations; however, to the authors’ knowledge, the following represent first detections: R. auricularia in Hyatt Reservoir and Paulina Lake, O. neglectus in Hyatt Reservoir and C. fluminea in Howard Prairie Lake. Close

• 5. [Article] Connecting Habitat Across Roads: Field Testing Mitigation Strategies for Reducing Road Mortality of an Imperiled Butterfly

  Roads impact wildlife in a variety of ways including fragmentation of populations, reduced access to habitat, and direct mortality from vehicle strikes. Such road effects likely impact the Oregon silverspot ...

  Citation × Citation Citation Abstract Copy Title: Connecting Habitat Across Roads: Field Testing Mitigation Strategies for Reducing Road Mortality of an Imperiled Butterfly Author: Littlejohn, Rebecca Jalene Year: 2012 Roads impact wildlife in a variety of ways including fragmentation of populations, reduced access to habitat, and direct mortality from vehicle strikes. Such road effects likely impact the Oregon silverspot butterfly (Speyeria zerene hippolyta) at one of its few remaining sites. The Rock Creek-Big Creek population of this threatened fritillary butterfly species is bisected by highway 101 on the central Oregon coast. Habitat resources for S. z. hippolyta are found on both the east and west sides of the highway at this site, and vehicle-strikes have been found to cause mortality of some individuals crossing the highway. The 2001 revised Recovery Plan calls out road mortality as a primary threat to S. z. hippolyta and land managers are considering mitigation strategies to reduce this threat on the population. A previous study at Rock Creek- Big Creek prioritized mitigation strategies including mowing of the road sides to decrease flowering plants along the verge and installation of vegetative hedgerows along the highway where the butterflies are crossing to encourage increased flight height over the road. Mowing has taken place over the last two years, but the hedgerows have neither been installed nor tested for effectiveness. This study investigates the effectiveness of hedgerows to increase the flight height of S. z. hippolyta through experimental tests using 3-meter tall nets as "guiding barriers" to mimic vegetative hedgerows in the flight path of S. z. hippolyta at another site in Oregon, Mt. Hebo. Mt. Hebo was chosen because of the stable population of S. z. hippolyta that is found there, the low risk of mortality for individual butterflies during the course of the study, and consistent use of a corridor by S. z. hippolyta. Treatments were designed to mimic a flight path in which a butterfly encounters a "road" of a width simulating that of highway 101 with 3-meter guiding barriers on either side. Based on previous research observations, it was hypothesized that S. z. hippolytaindividuals would fly over the guiding barriers at an increased "safe" flight height such that they would fly over traffic height. Results of the experimental study indicated that a 3-meter guiding barrier in the flight path of S. z. hippolyta did not significantly increase the flight height of individuals. None of the individuals observed flew at a safe flight height over the road (>3 meters). Further, S. z. hippolyta individuals landed on the road surface more often when there was a guiding barrier in the flight path. These results suggest that while S. z. hippolyta individuals are able to fly over guiding barriers in their path at heights of 3 meters or more, there is no evidence to suggest that these structures will influence flight height over highway 101 such that road mortality is reduced. Additionally, this study investigated the known butterfly crossing points at Rock Creek-Big Creek to test the hypothesis that S. z. hippolyta individuals are crossing at points of lower vegetation adjacent to the road. Using data from previous studies, ten crossing points were mapped at this site. Light detection and ranging data (LiDAR) was used to derive vegetation height along highway 101 and analyzed between known crossing points and random points within the Rock Creek-Big Creek area in addition to resource density of the larval host plant (Viola adunca) within the meadows. Statistical analysis indicated that the butterflies were generally crossing at points along the highway with significantly lower vegetation adjacent to the road. Visual analysis indicated that the butterflies were also generally crossing between areas of densely located V. adunca. Additional spatial data is needed to do further path-analysis of S. z. hippolyta individuals. Title: Connecting Habitat Across Roads: Field Testing Mitigation Strategies for Reducing Road Mortality of an Imperiled Butterfly Author: Littlejohn, Rebecca Jalene Year: 2012 Roads impact wildlife in a variety of ways including fragmentation of populations, reduced access to habitat, and direct mortality from vehicle strikes. Such road effects likely impact the Oregon silverspot butterfly (Speyeria zerene hippolyta) at one of its few remaining sites. The Rock Creek-Big Creek population of this threatened fritillary butterfly species is bisected by highway 101 on the central Oregon coast. Habitat resources for S. z. hippolyta are found on both the east and west sides of the highway at this site, and vehicle-strikes have been found to cause mortality of some individuals crossing the highway. The 2001 revised Recovery Plan calls out road mortality as a primary threat to S. z. hippolyta and land managers are considering mitigation strategies to reduce this threat on the population. A previous study at Rock Creek- Big Creek prioritized mitigation strategies including mowing of the road sides to decrease flowering plants along the verge and installation of vegetative hedgerows along the highway where the butterflies are crossing to encourage increased flight height over the road. Mowing has taken place over the last two years, but the hedgerows have neither been installed nor tested for effectiveness. This study investigates the effectiveness of hedgerows to increase the flight height of S. z. hippolyta through experimental tests using 3-meter tall nets as "guiding barriers" to mimic vegetative hedgerows in the flight path of S. z. hippolyta at another site in Oregon, Mt. Hebo. Mt. Hebo was chosen because of the stable population of S. z. hippolyta that is found there, the low risk of mortality for individual butterflies during the course of the study, and consistent use of a corridor by S. z. hippolyta. Treatments were designed to mimic a flight path in which a butterfly encounters a "road" of a width simulating that of highway 101 with 3-meter guiding barriers on either side. Based on previous research observations, it was hypothesized that S. z. hippolytaindividuals would fly over the guiding barriers at an increased "safe" flight height such that they would fly over traffic height. Results of the experimental study indicated that a 3-meter guiding barrier in the flight path of S. z. hippolyta did not significantly increase the flight height of individuals. None of the individuals observed flew at a safe flight height over the road (>3 meters). Further, S. z. hippolyta individuals landed on the road surface more often when there was a guiding barrier in the flight path. These results suggest that while S. z. hippolyta individuals are able to fly over guiding barriers in their path at heights of 3 meters or more, there is no evidence to suggest that these structures will influence flight height over highway 101 such that road mortality is reduced. Additionally, this study investigated the known butterfly crossing points at Rock Creek-Big Creek to test the hypothesis that S. z. hippolyta individuals are crossing at points of lower vegetation adjacent to the road. Using data from previous studies, ten crossing points were mapped at this site. Light detection and ranging data (LiDAR) was used to derive vegetation height along highway 101 and analyzed between known crossing points and random points within the Rock Creek-Big Creek area in addition to resource density of the larval host plant (Viola adunca) within the meadows. Statistical analysis indicated that the butterflies were generally crossing at points along the highway with significantly lower vegetation adjacent to the road. Visual analysis indicated that the butterflies were also generally crossing between areas of densely located V. adunca. Additional spatial data is needed to do further path-analysis of S. z. hippolyta individuals. Close