Although it might sound obvious to a human reader of this news — after all our mothers, and our fathers teach us where to get our food — the teaching of such a specific behavior in the natural world is not universal. Often, if involves instinctive behavior and in any case, documenting the mechanics of how the young of a species acquire such critical knowledge is extremely difficult. In the case of whales, it’s made all the more difficult because of the environment — wild ocean waters — in which they live and must be observed. Researchers at the University of Utah were recently able to document the transfer of feeding ground knowledge from mother southern right whales to their offspring, which raises concern about their ability to find new places to feed if Earth’s changing climate disrupts their traditional feeding grounds.
One of the co-authors of the study, Vicky Rowntree, research associate professor of biology at the University of Utah, said, “A primary concern is, what are whales going to do with global warming, which may change the location and abundance of their prey?” asks Vicky Rowntree, research associate professor of biology and a coauthor of the new study. “Can they adapt if they learn from their mother where to feed – or will they die?”
This new study — scheduled for publication in the Feb. 15 issue of the journal Molecular Ecology — used genetic and chemical isotope evidence to show that mothers teach their calves where to go for food.
“Southern right whales consume enormous amounts of food and have to travel vast distances to find adequate amounts of small prey,” says study coauthor Jon Seger, professor of biology at the University of Utah. “This study shows that mothers teach their babies in the first year of life where to go to feed in the immensity of the ocean.”
The study tracked how whales are related by analyzing maternal DNA, and then compared that with dietary information obtained by characterizing different forms or isotopes of chemical elements in their skin. The two techniques – which the researchers say they used together for the first time – allowed the scientists to determine that whale mothers, their offspring and other extended family members eat in the same place.
“North Atlantic right whales feed in similar patterns and scientists have access to their feeding areas, but we don’t know where South Atlantic whales are feeding, so we had to use a combination of techniques to track this down,” says Luciano Valenzuela, a postdoctoral researcher in biology who led the study as part of his doctoral thesis at Utah.
The study’s other coauthor was Mariano Sironi, scientific director of the Instituto de Conservación de Ballenas (Institute for the Conservation of Whales) in Argentina.
You can read more about this study HERE, including the sophisticated DNA techniques used to follow the locations of individual whales and groups. Materials for this story were provided by the University of Utah’s News Center.
Copyright © 2009 by Marine Science Today, a publication of OceanLines LLC