Reasons for unfulfilled breeding and transfer recommendations in zoos and aquariums

Abstract

One of the primary tools for cooperatively managing animal populations within the Association of Zoos and Aquariums is through Breeding and Transfer Plan (BTP) recommendations. These recommendations consider population demographics, genetics, husbandry, and institutional needs and aim to improve population viability and long‐term sustainability. However, fulfilling (i.e., completing) recommendations can be complicated by biological and logistical challenges. We examined institutional reasons for unfulfilled Breed With, Do Not Breed, Hold, and Send To recommendations collected in surveys in PMCTrack, software for tracking recommendation fulfillment, using descriptive and text‐mining methods. Overall, 73 Animal Programs used PMCTrack to distribute 2335 surveys and accrued responses from 167 zoos and aquariums from 2007 to 2019, with a response rate of 56% (n = 1307). For Breed With recommendations, common reasons were related to an individual animal's status and a pair's breeding behavior; for all other recommendation types, reasons were often management or logistical factors. Most Breed With recommendations were attempted (≥55%) but did not result in detectable pregnancy/eggs or offspring, due to pair incompatibility or not enough time to successfully produce offspring. Hold and Do Not Breed recommendations were often unfulfilled because the BTP recommendation was replaced with an interim (i.e., updated) recommendation during the inter‐planning period. Our results support the importance of some common population management practices, such as maintaining breeding pairs/groups for multiple BTPs to improve mate familiarity, examining husbandry mechanisms to promote breeding success, and making a concerted effort to adhere to planning timelines to facilitate transfers in alignment with breeding seasons.

Impacts of the COVID‐19 pandemic on population management in AZA

“…Before the pandemic, the average recommendation fulfillment rate was 20% for breeding recommendations (meaning the recommended pair successfully produced an offspring) and 57% for transfer recommendations (meaning the animal transferred to the listed facility) in the time between issuing the recommendations and creating the next BTP (Faust et al, 2019). For pre‐pandemic recommendations, most unfulfilled breeding recommendations were due to the individual animal becoming too old to breed, dying, or behavior of the pair (e.g., no courtship or copulation) that led to no offspring (Gray, Faust, Kuykendall, et al, 2022). Conversely, unfulfilled transfer recommendations were typically caused by facilities changing their management plans or receiving interim recommendations to follow (Gray, Faust, Kuykendall, et al, 2022).…”

“…For pre‐pandemic recommendations, most unfulfilled breeding recommendations were due to the individual animal becoming too old to breed, dying, or behavior of the pair (e.g., no courtship or copulation) that led to no offspring (Gray, Faust, Kuykendall, et al, 2022). Conversely, unfulfilled transfer recommendations were typically caused by facilities changing their management plans or receiving interim recommendations to follow (Gray, Faust, Kuykendall, et al, 2022).…”

Institutional networks in cooperative population management: Exploring patterns in transfer fulfillment

“…Transfers also serve as an essential tool in managing often limited holding space across institutions, compounded by unanticipated births, behavioral challenges within social groups, and exhibit renovations (Earnhardt et al, 2001). The main challenges to successful transfers are perceived to be communication and logistics between institutions, changing institutional wants and needs and alterations to husbandry practices (van Doorn, unpublished data; described in Lees & Wilcken, 2009;S. M. Gray et al, 2022).…”

“…BTPs provide recommendations for each individual animal on whether to breed and/or be transferred based on demographics, genetics, husbandry, welfare, logistics, and other species‐specific variables (AZA, 2018; Ballou et al, 2010; Powell et al, 2019). These recommendations are not requirements, and institutions may decide not to comply for various reasons (Lees & Wilcken, 2009) or compliance may be impossible due to issues ranging from biological incompatibility to institutional budget and staffing (Cronin et al, 2006; S. M. Gray et al, 2022). Understanding the factors affecting BTP fulfillment is key to success in meeting genetic and demographic goals for ex‐situ populations.…”

“…Transfers also serve as an essential tool in managing often limited holding space across institutions, compounded by unanticipated births, behavioral challenges within social groups, and exhibit renovations (Earnhardt et al, 2001). The main challenges to successful transfers are perceived to be communication and logistics between institutions, changing institutional wants and needs and alterations to husbandry practices (van Doorn, unpublished data; described in Lees & Wilcken, 2009; S. M. Gray et al, 2022). However, a recent study by S. Gray et al (2023) found reptile and amphibian transfer fulfillment was correlated with the diversity of Taxonomic Advisory Groups (TAGs; the management unit for related species) an institution participates in, suggesting that factors affecting transfer recommendation fulfillment go beyond simple logistics and husbandry.…”