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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] The Limitation of Spread of Non-native Marine Invertebrates from Artificial Structures to Natural Habitats

  Artificial structures created for aquatic anthropogenic activities are often colonized and fouled by many non-native species, few of which have invaded natural areas. Some research has indicated predation ...

  Citation × Citation Citation Abstract Copy Title: The Limitation of Spread of Non-native Marine Invertebrates from Artificial Structures to Natural Habitats Author: McClees, Whitney, de Rivera, Catherine E. Year: 2017 Artificial structures created for aquatic anthropogenic activities are often colonized and fouled by many non-native species, few of which have invaded natural areas. Some research has indicated predation is limiting the spread of non-native species, while other research has indicated that it is dispersal-driven. To determine the effects of dispersal limitation and predation on the risk to surrounding habitats of being invaded by non-native species established on marina docks, we used a three-factor design, deploying seven unglazed ceramic panels per each treatment combination of 1) inside versus outside a marina in Yaquina Bay, Oregon; 2) cage keeping out predators >mesh size, no cage, or partial cage; 3) fixed near the substrata (benthic) versus floating 1m below the surface. We also moved panels of either adults or recruits from floating in the marina to any of the treatment combinations to test if they would have lower survival outside by the substrate. The community on panels suspended in the marina only minimally overlapped with panels outside of the marina near the bottom. However, there was no difference between the cage treatments, which suggests that predators excluded by the cages are not responsible for the observed differences in species richness or composition. Title: The Limitation of Spread of Non-native Marine Invertebrates from Artificial Structures to Natural Habitats Author: McClees, Whitney, de Rivera, Catherine E. Year: 2017 Artificial structures created for aquatic anthropogenic activities are often colonized and fouled by many non-native species, few of which have invaded natural areas. Some research has indicated predation is limiting the spread of non-native species, while other research has indicated that it is dispersal-driven. To determine the effects of dispersal limitation and predation on the risk to surrounding habitats of being invaded by non-native species established on marina docks, we used a three-factor design, deploying seven unglazed ceramic panels per each treatment combination of 1) inside versus outside a marina in Yaquina Bay, Oregon; 2) cage keeping out predators >mesh size, no cage, or partial cage; 3) fixed near the substrata (benthic) versus floating 1m below the surface. We also moved panels of either adults or recruits from floating in the marina to any of the treatment combinations to test if they would have lower survival outside by the substrate. The community on panels suspended in the marina only minimally overlapped with panels outside of the marina near the bottom. However, there was no difference between the cage treatments, which suggests that predators excluded by the cages are not responsible for the observed differences in species richness or composition. Close