Coastal Restoration Trust of New Zealand

Coastal Dune Ecosystem Reference Database

Predicting harvest impact and establishment success when translocating highly mobile and endangered species Journal Paper

Author
JH Fischer, HU Wittmer, CF Kenup, KA Parker, R Cole, I Debski, GA Taylor, JG Ewen &; DP Armstrong
Year
2022
Journal / Source
Journal of Applied Ecology
Publisher / Organisation
British Ecological Society
Month
March 2022
Pages
13
ISBN / ISSN
doi: 10.1111/1365-2664.14219
Species
Pelecanoides whenuahouensis sp. nov.
Keywords
Bayesian inference, conservation, integrated population model, metapopulation dynamics, Pelecanoides whenuahouensis, philopatry, reintroduction, seabirds
Summary
1. Harvesting individuals for translocations can negatively impact source popula-tions, a critical challenge for species reduced to small populations. Consequently, translocation cohorts often remain small, reducing the establishment probability at the destination. Balancing the potential benefits and risks of such transloca-tions is further complicated by philopatry and natural metapopulation dynamics if the target species is highly mobile. These challenges highlight the importance of translocation feasibility assessments, but such assessments often remain qualitative to date. 2. The critically endangered Kuaka (Whenua Hou Diving Petrel; Pelecanoides when-uahouensis) is a philopatric, highly mobile seabird that could benefit from con-servation translocations, but only one small population remains. Through expert elicitations with a user-friendly Shiny app, we developed a novel metapopulation extension to an integrated population model fitted to long-term data, allowing us to simultaneously project harvest impact on the source and establishment of destination populations under alternative translocation scenarios, while ac-counting for philopatry and metapopulation dynamics. 3. Establishment of a destination population without excessive impact on the source was possible, but subject to uncertainty about philopatry and metap-opulation dynamics. Accounting for juveniles returning to the source post- translocations reduced impact on the source, but also decreased establishment at the destination. Natural movements of adults and juveniles between source and destination populations were predicted to modulate effects of different harvest intensities. 4. Synthesis and application. Using state- of- the art integrated population mod-els and expert elicitations, we illustrate how translocation feasibility can be evaluated transparently and quantitatively, even when targeting endangered, philopatric and highly mobile species. Our approach is a considerable improve-ment on current qualitative feasibility assessments. However, we also illustrate that, ultimately, the favoured translocation strategy depends on balancing bio-logical and other fundamental objectives inherent to translocations. Therefore, the ideal strategy cannot be determined solely mathematically, and feasibility assessments should incorporate explicit value statements. Our methodology is applicable to any future translocation scenario.