Abstract
AbstractBiological invasions are a major threat to biodiversity and have particularly devastating impacts on island ecosystems. The New Caledonia archipelago is considered a biodiversity hotspot due to its diverse native flora. Javan rusa deer (Rusa timorensis) were introduced to New Caledonia in 1870 and the population consists of several hundred thousand individuals today. They directly threaten rare endemic species and affect the composition and structure of the vegetation. While a rusa deer management plan has identified ten priority areas for deer control operations, removing deer could be offset by the dispersal of animals back into the control areas. Here, we genotyped 628 rusa deer using 16 microsatellite markers to analyse the genetic structure of the animals in New Caledonia. We aimed to assess fine-scale genetic structure, to identify natural barriers to deer movement and to assess functional connectivity by optimising individual-based landscape resistance models. Our results suggested that rusa deer formed a single genetic population on the main New Caledonian island. The isolation-by-distance pattern suggested that female dispersal was limited, whereas males had larger dispersal distances. We assessed functional connectivity using different genetic distance metrics and all models performed poorly (mR2 ≤ 0.0043). Landscape features thus hardly affected deer movement. The characteristics of our results suggested that they were not an artefact of the colonisation history of the species. Achieving an effective reduction of deer population sizes in specific management areas will be difficult because of the deer’s high dispersal capabilities and impossible without very substantial financial investment.
Funder
Agence pour l’Indemnisation des Calamités Agricoles ou Naturelles (APICAN)/Agence rurale
L‘Oréal-UNESCO For Women in Science Grant
Publisher
Springer Science and Business Media LLC
Subject
Management, Monitoring, Policy and Law,Nature and Landscape Conservation,Ecology, Evolution, Behavior and Systematics
Reference93 articles.
1. Amos M, Pople A, Brennan M, Sheil D, Kimber M, Cathcart A (2022) Home ranges of rusa deer (Cervus timorensis) in a subtropical peri-urban environment in South East Queensland. Aust Mammal 45:116–120. https://doi.org/10.1071/AM21052
2. Anderson EC, Dunham KK (2008) The influence of family groups on inferences made with the program Structure. Mol Ecol 8:1219–1229. https://doi.org/10.1111/j.1755-0998.2008.02355.x
3. Anonymous (2022) Réalisation d’opérations de lutte contre les ongulés envahissants. Projet Régional Océanien des Territoires pour la Gestion durable des Ecosystèmes. https://protege.spc.int/sites/default/files/documents/22_09_PROTEGE-FicheSuivi-EspecesEnvahissantes-13B.1_BD.pdf. Accessed 18 April 2023
4. Aronson J, Vallaur D, Jaffré T, Lowry P II (2005) Restoring dry tropical forest. In: Mansourian S, Vallauri D, Dudley N (eds) Restoring forests and their functions in landscapes, beyond planting trees. Springer, New York, pp 285–290
5. Barendse W, Armitage SM, Kossarek L et al (1994) A genetic linkage map of the bovine genome. Nat Genet 6:227–235. https://doi.org/10.1038/ng0394-227