Data for: Sources of intraspecific variation in the isotopic niche of a semi-aquatic predator in a human-modified landscape

Published: 28 March 2023| Version 1 | DOI: 10.17632/6dfzrxcsjz.1


Intraspecific variation modulates patterns of resource use by species, potentially affecting the structure and stability of food webs. In human-modified landscapes, habitat disturbance modifies trophic interactions and intraspecific niche variation, impacting population persistence. Here, we investigated effects triggered by sex, ontogeny, and habitat differences on the trophic niche of Caiman crocodilus in an agricultural landscape. We evaluated temporal variation in the trophic niche parameters using carbon and nitrogen stable isotope analysis from different body tissues. We found that caimans exploit the same carbon and nitrogen pools through time, with low isotopic variability between seasons. In part, due to slow isotope turnover rates of tissues in crocodilians. Conversely, the trophic niche of caimans varied across habitats, but with no difference between natural and anthropogenic habitats, apparently results from habitat suitability, connectivity, and caiman movements during the foraging. Females and males used similar resources, but reproduction leads to a larger niche in females than males. Further, ontogenetic trophic shifts depended on sex, leading to resource partitioning that can potentially reduce intraspecific competition. Since anthropogenic habitats can increase the susceptibility of caiman populations to harmful impacts, intraspecific variation should be the concern of decision-makers and stakeholders for sustainable management and conservation actions. For more information, read the README.txt



Universidade de Brasilia


Ecological Niche, Sexual Dimorphism, Stable Isotope


Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Project Number 23038.006832/2014-11

Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq


The Rufford Foundation


USAID’s PEER program