A poor international standard for trap selectivity threatens carnivore conservation

Abstract

Unintentional mortality of endangered carnivores due to non-selective trapping is important for conservation and warrants urgent attention. Currently, non-selective traps are being approved and used based on trap selectivity tests conducted according to International Organization for Standardization (ISO) guidelines. We review these guidelines and find them inadequate, because: 1) the ISO definition of selectivity does not account for relative abundance of target and non-target species and does not therefore meaningfully reflect selectivity; 2) the guidelines methodology at best quantifies relative selectivity of one trap against another, which is of limited use unless the control trap is known to have an acceptable level of absolute selectivity for the target species; 3) information on relative trap selectivity cannot simply be extrapolated elsewhere, unless species assemblage and relative species abundances are consistent. We demonstrate that the ISO definition of trap selectivity is only a simple capture proportion and therefore does not represent trap selectivity. ISO guidelines on trap selectivity should be reviewed to reflect particular ecological scenarios and we suggest how this might be done. Policy-makers, practitioners and researchers should interpret scientific results more cautiously. Trap approval decisions should be based on scientific evidence to avoid undermining the conservation of biodiversity.

Updating the AIHTS Trapping Standards to Improve Animal Welfare and Capture Efficiency and Selectivity

“…Over the last 20 years, countless datasets have been collected on the impact of trapping on animal welfare [ 10 ], trap selectivity and the impact of trapping on the persistence of animal populations [ 13 , 15 ], and the ethics of wildlife professionals and managers with respect to mammal trapping [ 2 , 9 , 10 , 72 , 97 ]. The development of better trapping standards should not require another 20 years due to a lack of definitions, a poor understanding of trapping research and development technology, or conceptual views about human–wildlife relationships.…”

“…The stated principle is to evaluate, in the field, the capability of a trap to capture target rather than non-target animals by recording the number of each that is captured by the test trap and by a control trap [ 6 , 7 ]. Virgós et al [ 13 ] reviewed these guidelines and found them inadequate because (1) the ISO definition of selectivity does not account for the relative abundance of target and non-target species and does not therefore meaningfully reflect selectivity; (2) the guidelines’ methodology at best quantifies the relative selectivity of one trap against another, which is of limited use unless the control trap is known to have an acceptable level of absolute selectivity for the target species; (3) as with capture efficiency, information on relative trap selectivity cannot simply be extrapolated elsewhere, unless species assemblage and relative species abundances are consistent. The ISO definition of trap selectivity in effect provides only a simple capture proportion and therefore does not represent trap selectivity [ 13 ].…”

“…The AIHTS standards are now more than 20 years old. Over this time, scientists have criticized these AIHTS for (1) omitting species that are commonly trapped [ 8 ]; (2) threshold levels of acceptance that are not representative of state-of-the-art trap technology [ 9 , 10 ]; (3) excluding commonly used traps which are known to cause prolonged pain and stress to captured animals [ 11 , 12 ]; (4) inadequate guidelines to assess capture efficiency and species selectivity (i.e., number of captures of target and non-target species) performance [ 13 ]. Concerns have been voiced by wildlife biologists, managers, and conservation groups about the ineffectiveness of standards and test procedures in ensuring animal welfare [ 14 ] and in implementing standards [ 12 , 15 , 16 ].…”

Evaluation of pay‐for‐release conservation incentives for unintentionally caught threatened species

“…Globally, the continued and increasing rate of incidental capture of animals that commonly include the most severely threatened species (Corlett ; Virgós et al. ) may jeopardize their permanence in the wild (Dulvy et al. ; Brashares et al.…”

“…Incidental capture of aquatic animals as bycatch in fisheries accounts for 40% of the global harvest (Keledjian et al 2014), and on land, unintentional captures of mammals and birds also occur via unselective capture methods (Noss 1998;Zöckler et al 2010;Becker et al 2013). Globally, the continued and increasing rate of incidental capture of animals that commonly include the most severely threatened species (Corlett 2007;Virgós et al 2016) may jeopardize their permanence in the wild (Dulvy et al 2003;Brashares et al 2004;Hays et al 2004). Remediation of this problem has chiefly focused on reducing the probability of capturing threatened species (Albrechtsen et al 2007;Komoroske & Lewison 2015;Leeney et al 2015).…”