North pacific climate mediates offspring sex ratio in northern elephant seals

Derek Lee, William J. Sydeman

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

Determinants of sex ratios in animal populations have been of general interest to ecologists for decades. We tested the hypothesis that offspring sex ratio in a population of northern elephant seals (Mirounga angustirostris) was related to large-scale environmental indices reflecting ocean climate and productivity that affected the condition of reproductive females over 31 years (1976-2006). More males were produced during years of weaker pressure differences and warmer sea surface temperature anomalies in the northeastern Pacific., conditions that reduce or disperse prey resources for gestating females in the North Pacific Ocean. For this species, sexually distinct forage resources exist, so competition for food resources occurs predominately within sex. These results are consistent with the resource competition model for facultative adjustments of offspring sex ratio. Anthropogenic global warming is predicted to warm the North Pacific. This could result in altered basin-scale ocean productivity, increased nutritional stress, and an overabundance of males that may adversely affect this and other similarly regulated mammalian populations.

Original languageEnglish (US)
Pages (from-to)1-8
Number of pages8
JournalJournal of Mammalogy
Volume90
Issue number1
DOIs
StatePublished - Feb 1 2009

Fingerprint

Earless Seals
Mirounga angustirostris
Sex Ratio
elephant
Climate
Oceans and Seas
sex ratio
climate
resource
oceans
Pacific Ocean
Population
Global Warming
ecologists
productivity
global warming
surface temperature
ocean
temperature anomaly
forage

All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Animal Science and Zoology
  • Genetics
  • Nature and Landscape Conservation

Cite this

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North pacific climate mediates offspring sex ratio in northern elephant seals. / Lee, Derek; Sydeman, William J.

In: Journal of Mammalogy, Vol. 90, No. 1, 01.02.2009, p. 1-8.

Research output: Contribution to journalArticle

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