Sex-specific median life expectancies from ex situ populations for 330 animal species.

We present life expectancy estimates for hundreds of vertebrate species based on carefully vetted studbook data from North American zoos and aquariums. These data include sex-specific median life expectancies as well as sample size and 95% confidence limits for each estimate. Existing longevity data for animals primarily consist of maximum lifespan values, which are single observations rather than statistically derived estimates of longevity. Moreover, all of our estimates are based on the same type of data and calculated using consistent, standardized methods. To derive these estimates, we conducted Kaplan-Meier survival analyses using individual-level demographic data (i.e., records of birth and mortality events) from studbook records for each ex situ population. Our species set represents a range of vertebrate taxa (primarily mammals, birds, amphibians, and reptiles) and diverse life histories. This dataset will have broad utility, not only for informing comparative demographic and life history studies, but also more broadly for any research or conservation application that requires sex- or species-specific life expectancy information.

Uncovering challenges to sustainability of AZA Animal Programs by evaluating the outcomes of breeding and transfer recommendations with PMCTrack.

The Association of Zoos and Aquariums (AZA) cooperatively manages Species Survival Plans® to create demographically and genetically viable populations. SSPs issue animal-specific recommendations to participating institutions via Breeding and Transfer Plans (BTPs). Fulfillment of recommendations is a crucial step in maintaining viable populations, but there have been no comprehensive evaluations of the system. Using PMCTrack, a database of over 110,000 breeding and transfer recommendations issued from over 200 SSPs from 1999 to 2013, we analyzed fulfillment of recommendations. Action-based recommendations had lower rates: Breed With recommendations were fulfilled at a rate of 20.0% before the next BTP, Send To at 56.8%, Do Not Breed at 95.7%, and Hold at 92.9%. We used generalized (logistic) mixed-effects model regressions to evaluate the impact of biological, management, and programmatic factors on fulfillment rates. For all recommendation types, there was significant variation in fulfillment among Programs and within Programs among BTPs. Out of 80 potential hypothesized fixed effects (20 factors * 4 recommendation types), only 20 effects (25%) were statistically significant. Rates were strongly influenced by temporal variables, generally increasing over time and as programs get older. Notably, the amount of time between BTPs was the only variable that significantly predicted fulfillment of all recommendation types. Many additional factors at the individual animal and institutional level may effect fulfillment rates and should be the subject of future analysis. Our results illustrate the utility of PMCTrack and indicate that improvements to the viability of SSPs will need to address multiple biological and management challenges.