Home range utilisation and long-range movement of estuarine crocodiles during the breeding and nesting season.

The estuarine crocodile (Crocodylus porosus) is the apex-predator in waterways and coastlines throughout south-east Asia and Australasia. C. porosus pose a potential risk to humans, and management strategies are implemented to control their movement and distribution. Here we used GPS-based telemetry...

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Main Authors: Hamish A Campbell, Ross G Dwyer, Terri R Irwin, Craig E Franklin
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2013-01-01
Series:PLoS ONE
Online Access:https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/23650510/?tool=EBI
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author Hamish A Campbell
Ross G Dwyer
Terri R Irwin
Craig E Franklin
author_facet Hamish A Campbell
Ross G Dwyer
Terri R Irwin
Craig E Franklin
author_sort Hamish A Campbell
collection DOAJ
description The estuarine crocodile (Crocodylus porosus) is the apex-predator in waterways and coastlines throughout south-east Asia and Australasia. C. porosus pose a potential risk to humans, and management strategies are implemented to control their movement and distribution. Here we used GPS-based telemetry to accurately record geographical location of adult C. porosus during the breeding and nesting season. The purpose of the study was to assess how C. porosus movement and distribution may be influenced by localised social conditions. During breeding, the females (2.92 ± 0.013 metres total length (TL), mean ± S.E., n = 4) occupied an area<1 km length of river, but to nest they travelled up to 54 km away from the breeding area. All tagged male C. porosus sustained high rates of movement (6.49 ± 0.9 km d(-1); n = 8) during the breeding and nesting period. The orientation of the daily movements differed between individuals revealing two discontinuous behavioural strategies. Five tagged male C. porosus (4.17 ± 0.14 m TL) exhibited a 'site-fidelic' strategy and moved within well-defined zones around the female home range areas. In contrast, three males (3.81 ± 0.08 m TL) exhibited 'nomadic' behaviour where they travelled continually throughout hundreds of kilometres of waterway. We argue that the 'site-fidelic' males patrolled territories around the female home ranges to maximise reproductive success, whilst the 'nomadic' males were subordinate animals that were forced to range over a far greater area in search of unguarded females. We conclude that C. porosus are highly mobile animals existing within a complex social system, and mate/con-specific interactions are likely to have a profound effect upon population density and distribution, and an individual's travel potential. We recommend that impacts on socio-spatial behaviour are considered prior to the implementation of management interventions.
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spelling doaj.art-479e9e61fbc14d08ab95a9e6ba3ef6e02022-12-21T23:09:10ZengPublic Library of Science (PLoS)PLoS ONE1932-62032013-01-0185e6212710.1371/journal.pone.0062127Home range utilisation and long-range movement of estuarine crocodiles during the breeding and nesting season.Hamish A CampbellRoss G DwyerTerri R IrwinCraig E FranklinThe estuarine crocodile (Crocodylus porosus) is the apex-predator in waterways and coastlines throughout south-east Asia and Australasia. C. porosus pose a potential risk to humans, and management strategies are implemented to control their movement and distribution. Here we used GPS-based telemetry to accurately record geographical location of adult C. porosus during the breeding and nesting season. The purpose of the study was to assess how C. porosus movement and distribution may be influenced by localised social conditions. During breeding, the females (2.92 ± 0.013 metres total length (TL), mean ± S.E., n = 4) occupied an area<1 km length of river, but to nest they travelled up to 54 km away from the breeding area. All tagged male C. porosus sustained high rates of movement (6.49 ± 0.9 km d(-1); n = 8) during the breeding and nesting period. The orientation of the daily movements differed between individuals revealing two discontinuous behavioural strategies. Five tagged male C. porosus (4.17 ± 0.14 m TL) exhibited a 'site-fidelic' strategy and moved within well-defined zones around the female home range areas. In contrast, three males (3.81 ± 0.08 m TL) exhibited 'nomadic' behaviour where they travelled continually throughout hundreds of kilometres of waterway. We argue that the 'site-fidelic' males patrolled territories around the female home ranges to maximise reproductive success, whilst the 'nomadic' males were subordinate animals that were forced to range over a far greater area in search of unguarded females. We conclude that C. porosus are highly mobile animals existing within a complex social system, and mate/con-specific interactions are likely to have a profound effect upon population density and distribution, and an individual's travel potential. We recommend that impacts on socio-spatial behaviour are considered prior to the implementation of management interventions.https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/23650510/?tool=EBI
spellingShingle Hamish A Campbell
Ross G Dwyer
Terri R Irwin
Craig E Franklin
Home range utilisation and long-range movement of estuarine crocodiles during the breeding and nesting season.
PLoS ONE
title Home range utilisation and long-range movement of estuarine crocodiles during the breeding and nesting season.
title_full Home range utilisation and long-range movement of estuarine crocodiles during the breeding and nesting season.
title_fullStr Home range utilisation and long-range movement of estuarine crocodiles during the breeding and nesting season.
title_full_unstemmed Home range utilisation and long-range movement of estuarine crocodiles during the breeding and nesting season.
title_short Home range utilisation and long-range movement of estuarine crocodiles during the breeding and nesting season.
title_sort home range utilisation and long range movement of estuarine crocodiles during the breeding and nesting season
url https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/23650510/?tool=EBI
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