D'em Bones!

In the late 1800s, the fledgling Smithsonian Institution acquired a lone Steller sea lion skull for its specimen collection. Some time before 1916, the skull was donated to Scotland’s Edinburgh University and later moved to its current home at the National Museums of Scotland. The skull’s origins will likely never be known, but after more than a century of storage in museum collections this well-traveled specimen may contribute to a better understanding of today’s Steller sea lions.

A team of scientists recently undertook an ambitious survey of 1,740 Steller sea lion skulls in 44 scientific collections around the world, with a view to determining whether enough historical data exists to support focused research on population declines in Alaska. Dr. Edward Miller of the Memorial University of Newfoundland, Dr. Øystein Wiig of the University of Oslo’s Natural History Museum, and Dr. Andrew Trites of the University of British Columbia’s Marine Mammal Research Unit directly examined or obtained information on specimens in collections in Canada, Germany, Japan, the Netherlands, Russia, the United Kingdom, and the United States.

A century of acquisitions has enhanced many of these collections, enabling modern scientists to study sea lion populations on unprecedented scales of time and geography. “Even without new collections,” the authors write, “existing collections of Steller sea lions are large and represent areas and times of interest for understanding population declines of the species.”

The specimens examined in the survey, 60% of which came from known locations in the United States, were well distributed across the species’ breeding range, including areas in which populations are declining. The survey results show that specimens have been collected at a higher rate in the last 32 years than over the first 127 years of the sampling period (the oldest specimen dated back to 1842). They also reveal periods of high collecting activity: the 1880s, during which time the Smithsonian Institution was actively expanding its collection; and the 1960s.

Because the survey included over 90% of the world’s collected Steller sea lion skulls, the authors express confidence in the accuracy of their data. But they note the survey was not exhaustive and does not include information from key Japanese and Russian collections, which total several hundred specimens. Other confounding factors included specimens with vague information about their origins, the inclusion of specimens from zoo animals, and the early practice of exchanging specimens between collections without documentation.

Based on their findings, the survey’s authors believe enough historical information exists to support further research, such as re-examining how Steller sea lion distribution has changed with time, or determining how individual size, morphology, or pathology vary between populations and with time. The researchers also point out the importance of obtaining samples from selected breeding sites and at specific times of year, to provide a more comprehensive range of information.

Biological collections have served a variety of purposes through the ages, from documenting early voyages of exploration to cataloguing the discoveries of modern scientific expeditions. In a world of rapidly dwindling biodiversity, however, these collections have become irreplaceable cultural treasures and a rich scientific
treasure trove: by catching a glimpse of the past, today’s researchers can give sea lions of the future a fighting chance for survival.

Publication:
International survey of scientific collections of Steller sea lions. Miller, E.H., A.W. Trites, and Ø. Wiig. 2005. Fisheries Centre Research Reports Vol 13(6) pp. 69 abstract We examined or obtained information on specimens of Steller sea lions in museums and other collections. We report on 1740 specimens (complete or partial skulls) in 44 collections in Canada, Germany, Japan, the Netherlands, Russia, the United Kingdom, and the United States. At least several hundred other specimens also exist, mainly in Japan and Russia. Collection dates range from 1842 to the present. Geographically, specimens are well represented in both ?Western? and ?Eastern? regions (separated at 144 W longitude): 509 and 956, respectively. Collection localities within Alaskan regions 2 (Eastern Gulf of Alaska) to 8 (Eastern Bering Sea) are represented by 290 specimens; another 566 specimens are from Japan and Russia and 462 from Alaska region 1 (Southeastern Alaska) southwards. Thus specimens are well spread across the species? breeding range, including areas of population decline. Representation is also good for the period of population decline and earlier per! iods: 442 specimens are from before 1960, 352 from 1960-69, 370 from 1970-79, and 487 from 1980 onwards. There are some problems with quality of data, and with seasonal and geographic representation, but we conclude that ample specimens exist to permit research pertinent to population declines in parts of the species? range.

27 October 2005