Impact of Plant Cover on Fitness and Behavioural Traits of Captive Red-Eyed Tree Frogs (Agalychnis callidryas)

Abstract

Despite the importance of ex situ conservation programmes as highlighted in the Amphibian Conservation Action Plan, there are few empirical studies that examine the influence of captive conditions on the fitness of amphibians, even for basic components of enclosure design such as cover provision. Maintaining the fitness of captive amphibian populations is essential to the success of ex situ conservation projects. Here we examined the impact of plant cover on measures of fitness and behaviour in captive red-eyed tree frogs (Agalychnis callidryas). We found significant effects of plant provision on body size, growth rates and cutaneous bacterial communities that together demonstrate a compelling fitness benefit from cover provision. We also demonstrate a strong behavioural preference for planted rather than non-planted areas. We also assessed the impact of plant provision on the abiotic environment in the enclosure as a potential driver of these behavioural and fitness effects. Together this data provides valuable information regarding enclosure design for a non-model amphibian species and has implications for amphibian populations maintained in captivity for conservation breeding programmes and research.

Diversity and stability of egg‐bacterial assemblages: The role of paternal care in the glassfrog Hyalinobatrachium colymbiphyllum

“…Some of these bacteria can confer resistance to infection from Batrachochytrium dendrobatidis (Harris et al 2006, 2009a,b, Lam et al 2010, an emerging fungal pathogen influencing global declines in amphibian populations (Daszak et al 2003, Wake & Vredenburg 2008. Current evidence indicates that the amphibian skin bacteria can be acquired and maintained via horizontal (host-to-host e.g., Rebollar et al 2016a), environmental (e.g., Michaels et al 2014, Loudon et al 2016, Rebollar et al 2016a, and/or vertical transmission (from parent to offspring, e.g., Banning et al 2008, Walke et al 2011. Vertical transmission of bacterial symbionts has been suggested to occur in two amphibian species with parental care based on the presence of similar bacteria on parents and their eggs: a salamander with maternal care, Hemidactylium scutatum (Banning et al 2008), and a frog with paternal care, Hyalinobactrachium colymbiphyllum (Walke et al 2011).…”

The effect of captivity on the skin microbial symbionts in threeAtelopusspecies from the lowlands of Colombia and Ecuador

“…Several studies have reported changes in the microbial associated communities when animals are moved from the wild to captive environments ( Isaacs et al, 2009 ; Dhanasiri et al, 2011 ; Wienemann et al, 2011 ; Nelson et al, 2013 ). In amphibians, research assessing the effect of captivity on bacterial communities is increasing ( Antwis et al, 2014 ; Becker et al, 2014 ; Michaels, Antwis & Preziosi, 2014 ; Kueneman et al, 2016 ). Through culture-independent and dependent approaches, these studies have demonstrated changes in the skin bacterial community composition due to conditions imposed by captivity.…”

“…Various studies have suggested that skin associated microbes of individuals in captivity differ from those in the wild ( Becker et al, 2014 ; Kueneman et al, 2016 ; Sabino-Pinto et al, 2016 ). In the case of the red-eyed tree frog ( Agalychnis callidryas ) , community composition, species richness, and abundance of bacterial groups seem to be influenced mainly by the availability of carotenoids in their diet ( Antwis et al, 2014 ), and by the cover provided in the enclosures ( Michaels, Antwis & Preziosi, 2014 ). However, other factors including humidity, temperature, pH and disinfection methods affect the presence of certain bacterial species and could facilitate or impede colonization and establishment in the host skin ( Mendoza et al, 2012 ).…”

“…For example, Becker et al (2015) showed that survival rates after exposure to Bd seem to be associated with the initial composition of the skin bacterial community, so different initial communities result in different outcomes for the host. Even though scientists have provided important insights on how different factors affect microbial assemblages in captive conditions ( Antwis et al, 2014 ; Michaels, Antwis & Preziosi, 2014 ; Michaels, Downie & Campbell-Palmer, 2014 ), additional research is required to determine the impact of captivity on the proportion of bacteria with anti- Bd properties for specific amphibian species. Knowing how captive conditions affect the proportion and performance of bacteria with antifungal capacities will allow us to more accurately predict the fate of species considered for reintroduction into the wild.…”

Amphibians and conservation breeding programmes: do all threatened amphibians belong on the ark?

“…Carotenoid availability also affects the composition of bacterial colonies associated with amphibian skin (Antwis et al 2014). Diverse bacterial colonies may offer protection against pathogens (Antwis et al 2014), but captive environments can significantly alter the bacterial skin floras implicated in disease resistance (Loudon et al 2013;Antwis et al 2014;Michaels et al 2014d); captive bred animals may therefore lack this protection.…”