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Stable isotope differences between sea lions (Zalophus) from the Gulf of California and Galapagos Islands
(Journal of Mammalogy, 2009)
Spatial or temporal isotopic variation, or both, in primary producers must be controlled for when investigating the foraging and trophic ecology of top consumers using isotopic data. Populations of the sister species ...
Can a 'wintering area effect' explain population status of Swainson's hawks? A stable isotope approach
(Wiley Blackwell Publishing, Inc, 2008-07)
It has been suggested that declines in breeding populations of Swainson's hawks (Buteo swainsoni) in California, Oregon, and Nevada may be due to differential mortality of hawks on their wintering grounds. Although massive ...
Ontogenetic changes in feeding habits of northern elephant seals revealed by δ15N and δ13C analysis of growth layers in teeth
(Marine Ecology Progress Series, 2012)
Stable isotope analysis is useful for examining the feeding strategies of mammals. Isotopes in the annual deposition growth layers of dentine in teeth permit assessment of ontogenetic dietary shifts in individuals, because ...
Trophic shift in the diet of the pelagic thresher shark based on stomach contents and stable isotope analyses
The trophic ecology of the pelagic thresher shark (Alopias pelagicus) was analysed using stomach contents and carbon (d13C)
and nitrogen (d15N) stable isotope analysis. The sharks were caught in Ecuadorian waters between ...
Stable oxygen and carbon isotope composition of holocene mytilidae from the camarones coast (Chubut, argentina): Palaeoceanographic implications
(MDPI AG, 2020-12)
The stable isotope composition of living and of Holocene Mytilidae shells was measured in the area of Camarones (Chubut, Argentina). The most striking results were the high δ18 O values measured in samples older than ca. ...
Zooarchaeological and Stable Isotopic Assessments on Pinniped-Human Relations in the Beagle Channel (Tierra del Fuego, Southern South America)
(John Wiley & Sons Inc, 2013-11)
Recent zooarchaeological investigations in the Beagle Channel region have shown long-term variations characterised by a high inter-taxonomic dominance of pinnipeds during the first moments of the archaeological sequence ...
Stable carbon isotopic composition of Brazilian beers-A comparison between large- and small-scale breweries
(Academic Press Inc Elsevier ScienceSan DiegoEUA, 2013)
Stable isotopes indicate differing foraging strategies in two sympatric otariids of the Galapagos Islands
(Journal of Experimental Marine Biology and Ecology, 2012)
The feeding behavior of marine predators varies with the level of competition to which they are exposed. Populations living in the same or overlapping geographic regions (sympatric) are generally subject to inter-specific ...