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Cited by 28Wildlife Ecology and ConservationGenetic diversity and population structureAmphibian and Reptile Biology

Translocation, genetic structure and homing ability confirm geographic barriers disrupt saltwater crocodile movement and dispersal

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Fukuda, Yusuke, Webb, Grahame, Manolis, Charlie, Lindner, Garry, Banks, Sam·2019·PLOS ONE
DOI 10.1371/journal.pone.0205862PMC PMC6713319
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Abstract

Translocated saltwater crocodiles (Crocodylus porosus) in the Northern Territory (NT) of Australia often return to their original capture sites, which complicates management interventions aimed at reducing human-crocodile conflict. We examined the spatial events implicated in this homing ability, using ARGOS satellite tracking devices. Five large male C. porosus (3.03 m to 4.02 m TL) were shifted and released 100-320 km from their capture sites, and 3 additional ones (3.67 m to 4.23 m TL) were released at their site of capture as controls. Translocated crocodiles were more mobile than the controls, and moved at sea in the direction of their original capture site. However, they were unable or unwilling to swim around a geographic structure, Cobourg Peninsula, which prevented homing being achieved in all five cases. Two control crocodiles remained near their capture sites, but one, after the first year, made a 900km journey for six months, before returning to its original capture and release site. Genetic analysis of tissue samples from nests across the NT coast demonstrated significant genetic structure across the coast, and confirmed that Cobourg Peninsula contributes to genetic differentiation among populations along the NT coast. These results provide new insights into C. porosus movements, which have management significance for the maintenance of public safety.

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  • Recent studies employing genome-wide SNP data have demonstrated substantial phylogeographic structure within C. porosus in Australia, indicating restricted gene flow and regional adaptation.

    “Recent studies employing genome-wide SNP data [68][69][70] have demonstrated substantial phylogeographic structure within C. porosus in Australia, indicating restricted gene flow and regional adaptation.”

    From Mitogenomic Crocodylia phylogeny and population structure of <i>Crocodylus porosus</i> including the extinct Seychelles crocodile (2026) · cites this paper as [69]

    The Results (Genetic analysis; page not provided) report regional clustering in 8,312 SNPs and less gene flow across the Cobourg Peninsula than among neighbouring populations on the same side. This supports geographic genetic structure and restricted gene flow in the sampled Northern Territory crocodiles, but the paper does not demonstrate regional adaptation. (LLM, conf=0.88)

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Cited by

Sorted by citations

Authors
Fukuda, Y., Webb, G., Manolis, C., Lindner, G., & Banks, S.
Affiliations
  • Australian National University (AU)
  • Charles Darwin University (AU)
  • Wildlife Management International (NZ)
  • Australian Government (AU)
Corresponding author
Fukuda, Yusuke
ORCID
Venue
PLOS ONE
Publisher
Public Library of Science (PLoS)
Published
2019-08-28
Volume
14
Issue
8
Pages
e0205862
ISSN
1932-6203 (ISSN-L)
DOI
10.1371/journal.pone.0205862
PMC
PMC6713319
OpenAlex
W2970753013
Cited by
28
References
1
Citations by year
2026: 2 · 2024: 2 · 2023: 6 · 2022: 6 · 2021: 7 · 2020: 5
FWCI
2.86
Type
journal article
Language
en
Open access
Licence
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • ANU Open Research (Australian National University) (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Figshare (submittedVersion, cc-by)
Funders
  • Department of Environment and Natural Resources, Northern Territory
  • National Geographic Society (51-16)
  • Holsworth Wildlife Research Endowment (HWRE2016R2027NEW)
  • IUCN-SSC Crocodile Specialist Group
  • ACT Herpetological Association
  • Parks Australia, Australia Government
  • Wildlife Management International Pty. Limited
Topics
  • Physical Sciences › Environmental Science › Ecology › Wildlife Ecology and Conservation
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Genetic diversity and population structure
  • Physical Sciences › Environmental Science › Global and Planetary Change › Amphibian and Reptile Biology
Keywords
saltwater crocodile, Crocodylus porosus, translocation, homing behavior, animal movement, dispersal, geographic barriers, Cobourg Peninsula, population structure, genetic differentiation, human-crocodile conflict, Argos satellite tracking
MeSH terms
Alligators and Crocodiles, Animals, Geography, Homing Behavior, Male, Movement, Spacecraft, Genetic Structures, Animal Distribution

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