For almost 10 years, Steller sea lion (Eumetopias jubatus) research has continued to be one of the largest research focuses at the Alaska SeaLife Center. It is no wonder either—Steller sea lion populations in western and south-central Alaska are still below historic numbers, have not fully recovered from significant population declines, and remain listed as endangered on the Federal Endangered Species List. It is not only important to study this species to ensure their survival, but to also learn more about the marine ecosystems in which they inhabit, and how they adapt to environmental change.
In 2001, the National Oceanic and Atmospheric Administration (NOAA), under the U.S. Department of Commerce, recognized the uniqueness of the Alaska SeaLife Center and our abilities to conduct field, captive, and laboratory studies by awarding the Research Department federal appropriations to support Steller sea lion research. Currently, the center is the only facility in the U.S. that houses Steller sea lions in captivity for research-specific purposes. There are currently three adult sea lions at the Alaska SeaLife Center —one male named Woody, and two females named Sugar and Kiska.
When pinniped declines in Alaska were becoming a national concern in the early 1990s, scientists began increasing their efforts to extensively study these species. By 1992, Congress appointed a Steller Sea Lion Recovery Team to identify research priorities for agencies to address that would help in the overall recovery and management of Steller sea lions. Steller sea lion research at the Alaska SeaLife Center is structured around several broad categories—all of which were prioritized as important areas of research by the Steller Sea Lion Recovery Team. Each category is termed important as they are directly linked to either understanding why this species declined or directly contributes to overall recovery of the species. To learn more about each specific project, click below.
All ASLC Steller sea lion research projects conducted in the U.S. are federally permitted and undergo Institutional Animal Care and Use Committee (IACUC) reviews. The research categories that broadly encompass our Steller sea lion research include:
By learning more about juvenile sea lion physiology and behavior, scientists may yield why this particular age class may be having difficulty surviving in the wild. With our special, quarentined facility (amicably named Steller South Beach) dedicated to temporarily housing wild juvenile sea lions, the Alaska SeaLife Center has quickly become one of the important forerunners for juvenile sea lion research. The facility, and its resulting research, has led to non-invasive and cutting edge developments that are pioneering new ways of studying and holding marine mammals in captive settings.
Transient killer whales are a considerable factor in Steller sea lion mortality. But how significant is this rate of mortality—enough to trigger population declines or their lack of recovery? Alaska SeaLife Center scientists and our collaborators are investigating the overall impact predation has upon Steller sea lions and other marine mammals. Several ongoing studies are examining metabolic requirements of killer whales and the tracking of killer whale movements.
Endocrinology & Contaminants
Steller sea lions spend the majority of their lives at sea, and inhabit some of the most extreme environments on earth. To maintain homeostasis in these environments, hormones must control growth, reproduction, and metabolism within the body. The system that regulates these hormones is called the endocrine system. Alaska SeaLife Center scientists are investigating the role the endocrine system plays in sea lion survival, and how contaminants such as DDT affect this important regulatory system.
In any mammal population, diseases have the potential to cause significant mortalities both indirectly and directly. Very little is known as to what diseases—parasitic, viral, or bacterial—Steller sea lions are vulnerable to, and have the potential to being exposed. Alaska SeaLife Center scientists and staff veterinarians are collecting samples from wild sea lions in the hopes of identifying potential diseases and parasites.
There are many components necessary for Steller sea lion survival, but perhaps the most important is the ability for sea lions to find food or prey. Metabolically, they must be able to locate, capture, and assimilate prey while expending less energy than the food they are capturing. To study this dynamic relationship—predator and prey — Alaska SeaLife Center research has investigated prey availability, sea lion foraging and assimilation efficiencies; prey ingestion rates; energetics of inter- and intra-specific prey; and metabolic demands of sea lions.
Researchers are using non-invasive, remote video monitoring equipment for long-term studies on behavior, movements, and mortality of Steller sea lions. Since 1998, scientists have video recorded sea lions at five different locations within Prince William Sound and Resurrection Bay. These cameras capture live, real-time video all of which is controlled with computer software at the main Alaska SeaLife Center facility! This approach allows researchers to collect and record data on reproductive success, extent of maternal care and investment, pup mortality, and other behavioral studies.
Though sea lions forage to survive, it is the quality of prey that determines how much they have to eat or consume. Alaska SeaLife Center scientists and our collaborators are exploring the nutritional qualities of different prey Steller sea lions eat, the effects different diets have upon sea lions, and understanding the energetic demands of Steller sea lions at different ages. Of particular interest is how much energy transfer is occurring between mother and pup during the critical months when pups depend upon milk as the primary food source.