On September 15th, 2026 Professor Emeritus Dr. Donald “Don” Siniff passed away at his home in Wisconsin. Don is the founder of this Erebus Bay Weddell Seal Population Study.

The following statement is from current Project Lead Scientist Prof. Jay Rotella:

As a faculty member of the Department of Ecology and Behavioral Biology at the University of Minnesota, Donald “Don” B. Siniff built on earlier work by Ian Stirling to establish the Weddell Seal Erebus Bay Population Study in 1968.

Within a short number of years, Don and his colleagues put in place the field methods of marking and surveying that are still used today and that have been used every year for decades to document the lives of individual seals and to track changes in the population’s size and composition. Don led the project for most years from 1968 through 2001 and wrote a number of important papers on Weddell seal ecology including an Ecological Monograph in 1977 that remains an important source of key information on the species and study population.

As documented in his obituary, “Don trained more than 50 Ph.D. students and helped establish foundations for marine mammal conservation and management in North America and beyond. He also served on numerous panels and committees, including the Marine Mammal Commission, the National Research Council Committee to Review the Bering Sea Ecosystem, the National Research Council Committee on Polar Research, and was appointed to the Scientific Committee on Antarctic Research by President Gerald Ford.”

Don and his students studied not only the population ecology of Weddell seals but also investigated a variety of other topics including genetics, movements, and territoriality to name a few. An impressive number of the graduate students that Don trained went on to have successful careers in marine ecology and have made and continue to make important contributions to marine mammal science and marine conservation.

In the early 2000’s, Don collaborated with Dr. Robert “Bob” Garrott, a professor at Montana State University who was one of Don’s Ph.D. students, to move the project to Montana State University where the project has been based since 2002. From 2002 until quite recently Don continued to be a valued collaborator of Bob Garrott and Jay Rotella, a faculty member at Montana State University who Bob got involved in the project.

Don’s legacy of establishing and conducting the project as well as the large number of students that he has trained has created an impressive and important legacy in marine mammal ecology and in the scientific understanding of Weddell seals. We are extremely impressed by his career and legacy and deeply appreciative of all he has accomplished. Fittingly, Don’s Antarctic work is recognized by having the water body between Verleger and Melville Points bear his name as “Siniff Bay”.

– Prof. Jay Rotella, Lead Scientist, Erebus Bay Weddell Seal Population Study