Skip to main content
WCS
Menu
Library
Library Catalog
eJournals & eBooks
WCS Research
Archives
Research Use
Finding Aids
Digital Collections
WCS History
WCS Research
Research Publications
Science Data
Services for WCS Researchers
Archives Shop
Bronx Zoo
Department of Tropical Research
Browse By Product
About Us
FAQs
Intern or Volunteer
Staff
Donate
Search WCS.org
Search
search
Popular Search Terms
WCS History
Library and Archives
Library and Archives Menu
Library
Archives
WCS Research
Archives Shop
About Us
Donate
en
fr
Title
Intraspecific trophic variation during the early chick-rearing period in Magellanic penguins Spheniscus magellanicus: Influence of age and colony location
Author(s)
Dodino, Samanta; Riccialdelli, Luciana; Polito, Michael J.; Pütz, Klemens; Rey, Andrea Raya
Published
2022
Publisher
Marine Biology
Published Version DOI
https://doi.org/10.1007/s00227-022-04100-4
Abstract
Intraspecific competition for food resources has the potential to be high for central-place foragers such as penguins and can result in spatial and dietary foraging niche segregation among individuals of the same species. We sampled adults, chicks, and juvenile individuals’ whole blood from three colonies of Magellanic penguins (Spheniscus magellanicus) from Tierra del Fuego along an inshore-offshore corridor. We analyzed the isotopic niche, the trophic position and the diet composition in penguins to investigate intraspecific trophic niche variation in relation to biological (age of individuals) and external factors (foraging habitats, colony location) using carbon (δ13C) and nitrogen (δ15N) stable isotope values. We found isotopic niche segregation between age classes within each colony. When comparing across colonies, only juvenile exhibited some degree of isotopic niche overlap among colonies. In addition, at all three colonies juveniles had the largest isotopic niches with relatively higher variation in δ13C values. All individuals consumed low trophic position (TP) prey items such as the pelagic form of Munida gregaria based on stable isotope mixing model results. Adults and juveniles incorporated high TP (silverside and nototheniids) prey items into their diets, except for juveniles from Martillo Island whose proportions mirror chicks’ values. These results denote that parents consumed different prey items for themselves than for their chicks. Intraspecific trophic niche partitioning between colonies showed a decreasing δ13C and δ15N values from the nearest inshore colony relative to the farther offshore colonies. Understanding within and between colonies foraging strategies are important to set up connectivity between populations, status of the different colonies, and to develop adequate conservation actions.
Keywords
intraspecific competition; trophic niche; stable isotopes; Southern Ocean; seabirds
Access Full Text
A full-text copy of this article may be available. Please email the
WCS Library
to request.
Back
PUB35712