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Background: Mesocosm experiments have become increasingly popular in climate change research as they bridge the gap between small-scale, less realistic, microcosm experiments, and large-scale, more complex, natural systems. Characteristics of aquatic mesocosm designs (e.g., mesocosm volume, study duration, and replication) vary widely, potentially affecting the magnitude and direction of effect sizes measured in experiments. In this global systematic review we aim to identify the type, direction and strength of climate warming effects on aquatic species, communities and ecosystems in mesocosm experiments. Furthermore, we will investigate the context-dependency of the observed effects on several a priori determined effect moderators (ecological and methodological). Our conclusions will provide recommendations for aquatic scientists designing mesocosm experiments, as well as guidelines for interpretation of experimental results by scientists, policy-makers and the general public. Methods: We will conduct a systematic search using multiple online databases to gather evidence from the scientific literature on the effects of warming experimentally tested in aquatic mesocosms. Data from relevant studies will be extracted and used in a random effects meta-analysis to estimate the overall effect sizes of warming experiments on species performance, biodiversity and ecosystem functions. Experimental characteristics (e.g., mesocosm size and shape, replication-level, experimental duration and design, biogeographic region, community type, crossed manipulation) will be further analysed using subgroup analyses.

Conservation breeding program practitioners select potential mates in an attempt to maximize pair compatibility and maintain genetic diversity. Therefore, pair duration, or the number of breeding seasons that individuals retain the same mate, is practitioner-determined in these settings. There is a critical need to evaluate whether pair duration influences reproductive success in ex situ assurance populations, particularly for socially monogamous species. The 'Alalā (Hawaiian crow, Corvus hawaiiensis) is a monogamous forest bird that is currently extinct in the wild. Today, 'Alalā exist only in human care for intensive conservation breeding. We analyzed breeding program data from 2018-2021 to determine the effects of 'Alalā pair duration and age on reproduction (nest building, egg laying, hatching, and fledging). We found that pair duration does not influence reproductive outcomes, and thus practitioners can be more proactive when re-pairing birds. Female and male age, on the other hand, influenced the probability of nest building, clutch production, and overall reproductive success. Nest building and clutch production probabilities were high (near 1) and stable as females aged from 2 to ~ 12 years old, declining sharply thereafter. In males, overall reproductive success (from building robust nests to rearing at least one nestling to fledge) increased with age from 2 to ~ 9 years old, peaked and reached an asymptote with males ≳ 9 to ~ 13 years old, and decreased in males = 13 years old. Thus, integrating age into the pair selection process will increase the likelihood of achieving conservation goals. To our knowledge, we are the first to utilize empirical pair duration results to provide specific management recommendations for mate selection in an avian conservation breeding program. Our findings have critical utility for guiding 'Alalā pairing decisions, and more broadly underscore the importance of evaluating mate retention and selection protocols in other conservation breeding programs. [ABSTRACT FROM AUTHOR]

For some critically endangered species, conservation breeding is a vital steppingstone toward re‐establishing wild populations. The 'Alalā (Hawaiian crow, Corvus hawaiiensis), currently extinct in the wild, exists today only in a conservation breeding program, which, for many years, utilized successful hands‐on husbandry approaches such as separating and resocializing pairs, providing partially manmade nests, artificially incubating eggs, and puppet rearing nestlings. Yet, a top priority of any conservation breeding program is to retain natural behaviors essential to postrelease survival and reproduction, to achieve successful reintroduction and restoration to the wild. We describe how we are adapting 'Alalā husbandry techniques to strengthen pair bonds through full‐time socialization, enable pairs to build robust nests, encourage females to incubate eggs to hatch, and provide pairs and their offspring with vital parental rearing experiences. We discuss the use of standardized, data‐driven methods to objectively track our progress towards successful parental breeding and to select release candidates based on their likelihood to survive and breed in the wild. The information shared in this report can be applied to other conservation breeding programs, particularly those implementing or transitioning to husbandry techniques geared towards preparing species to thrive in the wild. Research highlights: Conservation breeding techniques for 'Alalā are designed to prepare individuals to thrive in the wild.A top priority is to maintain natural, species‐typical behaviors that are essential for post‐release survival and reproduction.Pairs are quantitatively monitored to assess performance and to identify release candidates. [ABSTRACT FROM AUTHOR]

Conservation breeding programs can save species from extinction by establishing assurance populations that provide individuals for achieving species recovery goals in the wild. However, keeping animals in human care can result in the selection of phenotypes that may be suboptimal for post-release survival and reproduction. It is therefore essential that conservation breeding programs provide animals with naturalistic conditions that facilitate the performance of species-typical behaviors, an endeavor that is also a vital aspect of animal welfare. Here, we describe how we established a conservation breeding program for the 'Akikiki (Oreomystis bairdi), a Hawaiian honeycreeper that is facing imminent extinction in the wild. We share how we utilized the species' native habitat as a template for developing husbandry practices with a primary focus on how we simulate wild environmental conditions in enclosures, mimic naturalistic foraging experiences, and facilitate pair bonding and parental breeding behaviors., (© 2024 The Author(s). Zoo Biology published by Wiley Periodicals LLC.)

Conservation breeding programs for endangered species face challenges, notably in the development of husbandry techniques, complicated by the impracticality of conducting controlled experiments. To reduce uncertainty regarding what works in conservation breeding programs, it is essential to capture data. In avian breeding programs, the construction of quality nests and appropriate incubation and handling of eggs by the parents are essential prerequisites to the successful production of offspring. Here, we study factors influencing nest-building and parental incubation outcomes in 'alalā (Corvus hawaiiensis), which is extinct in the wild and numbers fewer than 130 individuals in human care. Using parent-incubated egg data from 2018 to 2021 (171 clutches, 55 pairs), we evaluated the role of husbandry factors in determining the quality of nests constructed by 'alalā and the likelihood of nest quality and other social and environmental factors to predict egg loss (breaking, cannibalization, or ejection of an egg from the nest). More than half of all eggs laid failed to reach the hatch date. Nest quality was the most influential predictor of egg loss, with eggs in higher quality nests more likely to reach the hatch date. Male age also influenced egg loss, with very young (3 years old) and older males (⪞12 years old) experiencing more egg loss. Furthermore, the two facilities and two aviary types also differed in the quality of nests 'alalā constructed, indicating that nest-building behavior can be influenced by husbandry practices. These findings reduce uncertainty and provide insights for recommended management interventions to facilitate successful reproduction in human care., (© 2024 Wiley Periodicals LLC.)