Strategic confiscation and placement of illegally collected turtles for maximizing conservation outcomes
Dates
Start Date
2021-01-01
End Date
2022-12-31
Summary
The U.S. Fish and Wildlife Service, working with state and federal agencies with regulatory authority over turtles in the northeastern U.S., makes decisions about the confiscation and disposition of multiple species of turtles encountered via legal and extra-legal trade routes. Illegal collection of wild animals for the pet trade has resulted in population declines (Stanford et al. 2020), and U.S. freshwater turtles are particularly vulnerable to illegal collection (Mali et al 2014). Decisions about the disposition of confiscated animals, including whether animals may be released in the wild, are complicated by uncertainty and risk, primarily of the health and genetic (i.e., originating population) status of individual animals. Decision-makers [...]
Summary
The U.S. Fish and Wildlife Service, working with state and federal agencies with regulatory authority over turtles in the northeastern U.S., makes decisions about the confiscation and disposition of multiple species of turtles encountered via legal and extra-legal trade routes. Illegal collection of wild animals for the pet trade has resulted in population declines (Stanford et al. 2020), and U.S. freshwater turtles are particularly vulnerable to illegal collection (Mali et al 2014). Decisions about the disposition of confiscated animals, including whether animals may be released in the wild, are complicated by uncertainty and risk, primarily of the health and genetic (i.e., originating population) status of individual animals. Decision-makers wish to maximize the conservation status of turtle populations in the wild, which are declining (or locally extirpated) in part because of illegal harvest. The problem is further complicated in that the decision to confiscate an illegally harvested turtle is a ‘linked decision,’ where the choices available to one decision maker may depend on the choices made by another decision maker. Risk is present in three facets of the decision. First, there is risk of decline to the turtle population if illegal harvest is not addressed (Stanford et al. 2020). Second, there is genetic inbreeding risk if repatriation of an individual introduces deleterious alleles into a population (Lynch 1990). Finally, handling and captivity may result in disease risk if a novel pathogen is introduced to a naïve population (Vaughan-Higgins 2019).
Objectives:
We propose to use tools from decision science and population viability analysis to frame and address this problem. This analysis will be comprised of 3 steps: (1) outlining a conceptual model to identify points of intervention and decision-making authority at each point, (2) parameterizing a tunable population viability analysis that can be used to predict the outcomes for populations of the linked decisions and (3) evaluating a decision tree to incorporate uncertainties and the linked decisions to identify optimal solutions.
We will use wood turtles as a case study, a species listed under Appendix II of CITES, meaning that they are at risk for extinction given current levels of trade. Wood turtles have an active working group, are well-studied relative to other at-risk turtles, and is a species for which we have developed baseline population models. There are confiscation data for this species, including genetic population assignment tests. The USFWS and partners can expand this case study for other turtle species of trade concern (e.g., spotted turtles, eastern box turtles, Blanding’s turtles, and diamondback terrapins).
We have worked with decision makers from USFWS, AZA, and States to frame the decisions they are facing. It is clear that these decisions are linked; i.e. they are dependent on antecedent decisions. For example, the decision to confiscate a turtle depends on the availability of a temporary holding facility, and whether or not a turtle can be subsequently released to the wild. These decisions are made by different management agencies, who may be constrained by resources (space, funding) or uncertainty (disease status, population origin). By clarifying the jurisdiction, the objectives, risk tolerances, and the allowable tradeoffs by each agency, the proposed analysis will improve coordination in repatriating or releasing confiscated turtles to the wild.
