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RESEARCH INTERESTS
Behavioral ecology of whales and whale lice
Longitudinal life-history studies of southern right whales
Social interactions of mother-calf pairs
Effects of harrassment by kelp gulls on calf growth and mortality
Conservation of right whales and critical habitats
PUBLICATIONS
The large whales have vast ranges and many are at risk of
extinction -- not from hunting (which has stopped), but
from habitat destruction (which is increasing). In 1970,
Roger Payne and several of my other colleagues at the Whale
Conservation Institute/Ocean Alliance (WCI/OA) began a long-term
study of the right whales that calve at Península Valdés,
Argentina. I
have been a member of this team since 1976 and its director
since 1990. We identify individual whales from the white
markings (callosities) on their heads. By analyzing
photographs taken during annual aerial surveys of the
population we have assembled a demographic database that
now includes records of more than 1,800 individuals. Some
of these are "old friends" first identified in the early
1970s and resighted many times since then, often with new
calves. These data have allowed us to generate ever-better
estimates of the total population size and growth rate, and
to document changing pattern of habitat use.
Península Valdés is the best place in the world to observe
whales non-invasively. Mothers with calves stay in
shallow water at the base of tall cliffs, so observers on
land can follow the same individuals without disturbing
them for hours at a time. My specific research interests
center on social interactions among females on the nursery
ground, and on the relationship between a calf's activity
patterns and its mother's blubber reserves. By combining
behavioral observations and retrospective analysis of the
long-term photographic database, we documented an emerging
problem of harassment by kelp gulls which have learned to
feed on skin and blubber that they gouge from the whales's
backs. We are also examining acoustic and other mechanisms
of social cohesion, and the rates and causes of calf
mortality.
Many questions about right whales remain unanswered. They
are on the nursery ground for only three months each year
and most females return only every third year. Where do
they go? Stable isotope analyses suggest that the whales
feed in more than one location, but the isotopic signatures
of prey in the Southern Hemisphere have not been mapped.
The geographic distribution of mitochondrial haplotypes
shows that most females return to their natal nursery
grounds, but what about males? Researchers in Brazil,
Uruguay, Argentina, South Africa, Australia and New Zealand
have catalogues of right whales seen off their shores. We
are now beginning to standardize our data formats so that
newly designed software will allow us to search for
resightings of the same individual anywhere in the Southern
Hemisphere.
Right whale callosities are blanketed by thousands of
amphipod crustaceans called cyamids or "whale lice".
Cyamids have no free-swimming stage and spend their entire
lives clinging to their cetacean hosts. While studying
some of their adaptations to this unusual way of life, I
realized that they could tell us a great deal about the
lives of their hosts. Recent genetic studies by Jon Seger
and former undergraduate Ada Kalizewska have shown that
cyamids, unlike whales, have huge, unstructured populations
and very high levels of genetic diversity. Cyamid genomes
may contain much more information about right-whale
population history than do the whales' own genomes.
I work closely with an Argentine NGO (Instituto de
Conservación de Ballenas [ICB]) which has become a highly visible
and effective voice for right whales and their habitat. I
find it very exciting and satisfying to be involved,
locally, in practical and public applications of a study
that has consumed me scientifically for nearly three
decades.
Best, P.B., R. Payne, V. Rowntree, J.T. Palazzo and M.D.C.
Both. 1993. Long-range movements of South Atlantic right
whales Eubalaena australis. Marine Mammal Science
9(3):227-234.
Rowntree, V.J. 1996. Feeding, distribution, and
reproductive behavior of cyamids (Crustacea: Amphipoda)
living on humpback and right whales. Can. J. Zool.
74:103-109.
Rowntree, V.J., P. MacGuiness, K. Marshall, R. Payne, J.
Seger, and M. Sironi. 1998. Increased harassment of right
whales (Eubalaena australis) by kelp gulls (Larus
dominicanus) at Península Valdés, Argentina. Marine Mammal
Science 14(1):99-115.
Rowntree, V. J., R.S. Payne and D.M. Schell. 2001. Changing
patterns of habitat use by southern right whales (Eubalaena
australis) on their nursery ground at Península Valdés,
Argentina, and in their long-range movements. Journal of
Cetacean Research and Management (Special Issue) 2: 133-
143.
Cooke, J. G., R. Payne and V.J. Rowntree. 2001. Estimates
of demographic parameters for southern right whales
(Eubalaena australis) observed off Península Valdés,
Argentina. Journal of Cetacean Research and Management
(Special Issue) 2: 125-132.
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