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
Breeding habitat requirements of the Imperial Cormorant and Rock Shag in Central Patagonia, Argentina
Author(s)
Punta, G; Yorio, P; Saravia, J; Borboroglu, PG
Published
2003
Publisher
Waterbirds
Abstract
We studied the habitat requirements and nest site characteristics of Imperial Cormorants (Phalacrocorax atriceps) and Rock Shags (P. magellanicus) in northern Golfo San Jorge, Argentina. Colonies of both species were only located on islands. We characterized nesting habitat at 15 and 31 islands with and without Imperial Cormorant colonies, and 19 and 27 islands with and without Rock Shag colonies, respectively. The probability of finding nesting cormorants and shags was independent of island size. Both cormorants and shags nested on only 18% of islands or islets closer than one km to the mainland, but nested in between 35% and 52% of islands located further offshore. All Imperial Cormorant and Rock Shag colonies were located on bare, rocky substrate. All colonies of both species were located more than 50 m from shrubs. The mean slope of the substrate where colonies were located was significantly greater for Rock Shags than for Imperial Cormorants (73degrees vs. 3degrees). Orientation of cliffs and steep slopes where Rock Shags nested was mostly to the east. Over 86% of Imperial Cormorant colonies were located on the side of the island facing the open sea. Both height and depth of the nest were significantly larger for the Rock Shag, while internal diameter was significantly larger for Imperial Cormorant nests. The distribution patterns of cormorants and shags at the northern sector of Golfo San Jorge appears to be largely determined by the presence of islands, with availability of open rocky substrate and low shrub vegetation cover.
Keywords
NEST-SITE CHARACTERISTICS; MAGELLANIC PENGUINS; SELECTION; SUCCESS; SEABIRDS; TERNS; GULL
Access Full Text
A full-text copy of this article may be available. Please email the
WCS Library
to request.
Back
PUB11244