The following paper was published in Molecular Ecology's
EarlyView today.
Isotopic and genetic evidence for culturally inherited site fidelity to
feeding grounds in southern right whales (Eubalaena australis).
Luciano O. Valenzuela, Mariano Sironi, Victoria J. Rowntree and Jon
Seger. DOI: 10.1111/j.1365-294X.2008.04069.x
Abstract
Ocean warming will undoubtedly affect the migratory patterns of many
marine species, but specific changes can be predicted only where
behavioural mechanisms guiding migration are understood. Southern right
whales show maternally inherited site fidelity to near-shore winter
nursery grounds, but exactly where they feed in summer (collectively
and individually) remains mysterious. They consume huge quantities of
copepods and krill, and their reproductive rates respond to
fluctuations in krill abundance linked to El Niño Southern Oscillation
(ENSO). Here we show that genetic and isotopic signatures, analysed
together, indicate maternally directed site fidelity to diverse summer
feeding grounds for female right whales calving at Península Valdés,
Argentina. Isotopic values from 131 skin samples span a broad range
(–23.1 to –17.2‰δ13C, 6.0 to 13.8‰δ15N) and are more similar than
expected among individuals sharing the same mitochondrial haplotype.
This pattern indicates that calves learn summer feeding locations from
their mothers, and that the timescale of culturally inherited site
fidelity to feeding grounds is at least several generations. Such
conservatism would be expected to limit the exploration of new feeding
opportunities, and may explain why this population shows increased
rates of reproductive failure in years following elevated sea-surface
temperature anomalies off South Georgia, the richest known feeding
ground for baleen whales in the South Atlantic.
Thanks,
Luciano Valenzuela
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Luciano O. Valenzuela
Postdoctoral Researcher
Department of Biology
University of Utah
257 South 1400 East
Salt Lake City, UT, 84112, USA
Phone: 1-801-587-3405
valenzuela@biology.utah.edu
http://ecophys.biology.utah.edu