Factors affecting frog density in the Solomon Islands
Patrick Pikacha A B E , Chris Filardi C , Clare Morrison D and Luke Leung AA School of Agriculture and Food Sciences, University of Queensland, Gatton, Qld 4343, Australia.
B School of Civil Engineering, University of Queensland, St Lucia, Qld 4067, Australia.
C Pacific Programs, American Museum of Natural History, New York, USA.
D International Centre for Ecotourism Research, Griffith University, Gold Coast, Qld 4215, Australia.
E Corresponding author. Email: p.pikacha@uq.edu.au
Pacific Conservation Biology 22(3) 223-235 https://doi.org/10.1071/PC14927
Submitted: 27 August 2015 Accepted: 1 November 2015 Published: 12 February 2016
Abstract
This paper identifies some important factors affecting the density of frogs in the Solomon Islands. Distance sampling was used to estimate frog density in all major frog habitats across 13 islands. A total of 109 transects, covering five forest types (coastal, freshwater marshes, lowland forest, hill or ridge, and montane forest) were used, with 16 species being sampled. Estimated densities ranged from 2 ha–1 to 675 ha–1. Akaike’s Information Criterion (AIC) was used to select the most parsimonious model of frog density. Factors identified in the selected model to predict density of Batrachylodes elegans, Batrachylodes vertebralis, Ceratobatrachus guentheri, Discodeles bufoniformis, Discodeles guppyi, Discodeles malukuna, Litoria thesaurensis, Palmatorappia solomonis, Platymantis guppyi, Platymantis neckeri, Platymantis solomonis, Platymantis sp., Platymantis weberi, and Rana kreffti were island, landform, and forest type. Additional factors such as disturbance, leaf litter, shrub, and understorey were also described by the regression model as predictors of density for B. vertebralis, C. guentheri, D. guppyi, D. malukuna, Pal. solomonis, P. guppyi, and R. kreffti. These findings have important management implications for the conservation of frogs in the Solomon Islands. High densities of most species were strongly related with forest type and low disturbance. Preservation of rainforest, in especially high conservation value old-growth forests, is imperative to protecting these species.
Additional keywords: conservation, density, forest type, frogs.
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