Scale-Dependent Habitat Selection and Size-Based Dominance in Adult Male American Alligators.

Bradley A Strickland, Francisco J Vilella, Jerrold L Belant
Author Information
  1. Bradley A Strickland: Department of Wildlife, Fisheries, and Aquaculture, Mississippi State University, Mississippi State, Mississippi, United States of America.
  2. Francisco J Vilella: U.S. Geological Survey, Mississippi Cooperative Fish and Wildlife Research Unit, Mississippi State University, Mississippi State, Mississippi, United States of America.
  3. Jerrold L Belant: Carnivore Ecology Laboratory, Forest and Wildlife Research Center, Mississippi State University, Mississippi State, Mississippi, United States of America.

Abstract

Habitat selection is an active behavioral process that may vary across spatial and temporal scales. Animals choose an area of primary utilization (i.e., home range) then make decisions focused on resource needs within patches. Dominance may affect the spatial distribution of conspecifics and concomitant habitat selection. Size-dependent social dominance hierarchies have been documented in captive alligators, but evidence is lacking from wild populations. We studied habitat selection for adult male American alligators (Alligator mississippiensis; n = 17) on the Pearl River in central Mississippi, USA, to test whether habitat selection was scale-dependent and individual resource selectivity was a function of conspecific body size. We used K-select analysis to quantify selection at the home range scale and patches within the home range to determine selection congruency and important habitat variables. In addition, we used linear models to determine if body size was related to selection patterns and strengths. Our results indicated habitat selection of adult male alligators was a scale-dependent process. Alligators demonstrated greater overall selection for habitat variables at the patch level and less at the home range level, suggesting resources may not be limited when selecting a home range for animals in our study area. Further, diurnal habitat selection patterns may depend on thermoregulatory needs. There was no relationship between resource selection or home range size and body size, suggesting size-dependent dominance hierarchies may not have influenced alligator resource selection or space use in our sample. Though apparent habitat suitability and low alligator density did not manifest in an observed dominance hierarchy, we hypothesize that a change in either could increase intraspecific interactions, facilitating a dominance hierarchy. Due to the broad and diverse ecological roles of alligators, understanding the factors that influence their social dominance and space use can provide great insight into their functional role in the ecosystem.

References

  1. J Anim Ecol. 2011 Jul;80(4):786-98 [PMID: 21418209]
  2. J Appl Ecol. 2008 Oct;45(5):1382-1391 [PMID: 19330031]
  3. Biol Rev Camb Philos Soc. 2007 May;82(2):291-318 [PMID: 17437562]
  4. Ecology. 2008 Mar;89(3):838-46 [PMID: 18459346]
  5. Monogr Popul Biol. 1972;5:1-217 [PMID: 4680650]
  6. J Anim Ecol. 2010 Jan;79(1):4-12 [PMID: 19732211]
  7. J Exp Zool. 2002 Dec 15;294(4):325-33 [PMID: 12461812]
  8. Ecol Lett. 2012 Oct;15(10):1189-98 [PMID: 22897772]
  9. PLoS One. 2014 Jan 15;9(1):e83953 [PMID: 24454711]

MeSH Term

Alligators and Crocodiles
Animals
Behavior, Animal
Body Size
Ecosystem
Male
Social Dominance
United States

Word Cloud

Created with Highcharts 10.0.0selectionhabitathomerangemaydominanceresourcealligatorssizebodyHabitatprocessspatialareaneedswithinpatchesDominancesocialhierarchiesadultmaleAmericanscale-dependentuseddeterminevariablespatternsAlligatorslevelsuggestingalligatorspaceusehierarchyactivebehavioralvaryacrosstemporalscalesAnimalschooseprimaryutilizationiemakedecisionsfocusedaffectdistributionconspecificsconcomitantSize-dependentdocumentedcaptiveevidencelackingwildpopulationsstudiedAlligatormississippiensisn=17PearlRivercentralMississippiUSAtestwhetherindividualselectivityfunctionconspecificK-selectanalysisquantifyscalecongruencyimportantadditionlinearmodelsrelatedstrengthsresultsindicateddemonstratedgreateroverallpatchlessresourceslimitedselectinganimalsstudydiurnaldependthermoregulatoryrelationshipsize-dependentinfluencedsampleThoughapparentsuitabilitylowdensitymanifestobservedhypothesizechangeeitherincreaseintraspecificinteractionsfacilitatingDuebroaddiverseecologicalrolesunderstandingfactorsinfluencecanprovidegreatinsightfunctionalroleecosystemScale-DependentSelectionSize-BasedAdultMale

Similar Articles

Cited By