Habitat use by an endemic and a non-native gecko: natural habitat provides a last refuge for the Barbados Leaf-Toed gecko

Abstract

Island endemic reptiles face many threats that potentially have a negative effect on their conservation status, such as habitat loss, interactions with introduced predators and competitors, and stochastic environmental events. Since confirmation of the continued existence of the Barbados Leaf Toed gecko (Phyllodactylus pulcher) on the island of Barbados, West Indies, efforts have been made to increase ecological knowledge of the gecko in order to inform conservation direction and safeguard this critically endangered endemic species. The present study is the first to determine the microhabitat use of P. pulcher and that of the non-native gecko Hemidactylus mabouia on Barbados, and makes comparison to patterns of displacement of native geckos following Hemidactylus spp. invasions seen elsewhere. Factor Analyses of gecko locations and habitat data collected during night-time surveys indicated a strong nonrandom selection by P. pulcher for structurally diverse, rock habitat with an abundance of natural crevices. Where H. mabouia is present in natural habitat along the Barbados coast, the species also selected for exposed rocky habitat, albeit to a significantly lesser degree than did P. pulcher. Measures of body condition suggest the non-native gecko is less able to exploit such habitats and that its ability to thrive on Barbados is due to utilisation of a broader niche as befitting a habitat "generalist", rather than competitive displacement of the native gecko from cliff side habitat. Our findings highlight the importance for protection of the remaining natural cliff side habitat and promotion of biosecurity on Barbados as being key to the survival of P. pulcher.

How the African house gecko (Hemidactylus mabouia) conquered the world

“…[ 26 , 31 , 74 , 75 ]). Hemidactylus mabouia ss is a scansorial generalist with a preference for open, human-dominated habitats [ 76 ], though it is also found in natural habitats in both the New World and Africa [ 30 ]. Of 70 of our unique H. mabouia ss localities in Africa, only 14 were from either forest or field stations within forest.…”

High occupancy of European leaf-toed geckoEuleptes europaeain two island stands ofEucalyptus sp.: tree selection, co-occurrence and habitat effect

“…The latter is a massive gecko known for its strong territoriality and frequent agonistic behaviour (Lisicic et al 2012; Salvador 2016), and it is suspected of having caused the decline of E. europaea in a mainland locality (Renet et al in prep .). The arrival of T. mauritanica on Levant Island is likely to lead to behavioural responses in the E. europaea population: for example, asynchronous activity rates (Luiselli & Capizzi 1999) or the emergence of avoidance strategies such as retreating into specialised habitats (Delaugerre et al 2019; Williams et al 2020a, b). This will certainly have a cost that needs to be assessed in the future.…”

Interactions between the endemic gecko Phelsuma inexpectata and the introduced Phelsuma laticauda: understanding the drivers of invasion on Reunion Island

“…In lizards, inter-specific interactions are complex with subtle differences in behaviour and habitat occupancy that allow coexistence, such as differences in activity peaks (Luiselli & Capizzi, 1999;Porcel et al, 2021), use of supports (Williams et al, 2020;Porcel et al, 2021), food resources (Simbula et al, 2019), and sometimes distinct diurnal and nocturnal roosting sites (Zughaiyir, 2016;Zduneck, 2022;Meek & Luiselli, 2022). All species of the genus Phelsuma are frequent visitors of floral food resources, these are often very localised, thus attracting several individuals to the same location.…”

“…In addition, P. inexpectata has colonised only specific sections of the botanical garden whereas P. laticauda is now found widely across the whole estate, suggesting the use of a wider range of habitats. The displacement of other native gecko populations by non-native lizards to more specialised habitats has been documented, a good example being Phyllodactylus pulcher by Hemidactylus mabouia in Barbados (Williams et al, 2020).…”