10.26686/wgtn.12510497.v1
Heiko Wittmer
Heiko
Wittmer
DA Kelt
DA
Kelt
PA Kelly
PA
Kelly
DF Williams
DF
Williams
Use of simulation modeling to evaluate management strategies for reintroduced riparian brush rabbits in California
Open Access Te Herenga Waka-Victoria University of Wellington
2020
population modeling
reintroduction
endangered species
extinction risk
San Joaquin Valley
riparian brush rabbit
Sylvilagus bachmani riparius
Science & Technology
Life Sciences & Biomedicine
Biodiversity Conservation
Ecology
Biodiversity & Conservation
Environmental Sciences & Ecology
POPULATION VIABILITY ANALYSIS
TRANSLOCATION SUCCESS
WILD RABBITS
BIOLOGY
MAMMALS
CONSERVATION
DIRECTIONS
SELECTION
2020-06-18 22:48:11
Journal contribution
https://openaccess.wgtn.ac.nz/articles/journal_contribution/Use_of_simulation_modeling_to_evaluate_management_strategies_for_reintroduced_riparian_brush_rabbits_in_California/12510497
© 2016, U.S. Fish and Wildlife Service. All rights reserved. The riparian brush rabbit Sylvilagus bachmani riparius is restricted to areas of dense cover along rivers and tributaries in the Central Valley of California, USA, and is considered endangered under the U.S. Endangered Species Act. An approved recovery plan for this subspecies recommended establishment of three additional self-sustaining populations within its historical range. Concurrent with habitat restoration efforts that included revegetation of levees and provision of flood refugia, we reintroduced 325 captive-bred individuals to the San Joaquin River National Wildlife Refuge between July 2002 and July 2005, and monitored their survival with radiotelemetry. Using available survival estimates and estimated reproductive parameters, we developed a population viability analysis model to determine the risk of extinction of the reintroduced population under a series of alternate scenarios including different release strategies. All model scenarios resulted in high probabilities of extinction over 20 y in the absence of either ongoing supplementations or significant improvements to vital rates. Extinction risks over 20 y appeared independent of initial release strategies. The risk of extinction remained high (>99%) even when the initial founder population was supplemented with captive-bred brush rabbits for up to 10 y. Supplementing the population annually for the entire 20-y period would be required for the population to persist given current estimates of vital rates. These results suggest that the reintroduced population is not self-sustaining and continued releases will not provide the anticipated longterm benefits. Additionally, our understanding of the integral components of habitat and potential limiting factors should be refined to address their influence on demographics and the cause of brush rabbit declines at the release site in a comprehensive way. These results underscore the importance of viability analyses and developing testable hypotheses about potential limiting factors early in reintroduction efforts to more efficiently guide data-gathering and monitoring criteria, identify data deficiencies, and refine reintroduction techniques in the early stages of management.