While at the New York Aquarium Paul Sieswerda began a project to count seals that were returning to Staten Island each winter. He modeled the project on the Christmas Bird Count conducted by the National Audubon Society. Beginning in 1900 the Audubon Society asked their members to make a count of all the birds they saw on a particular day around Christmas. This was an outgrowth of a tradition where hunters would see how many birds they could kill, not for food, but for what, at that time, was considered sport. Frank Chapman, an early founder of the Audubon Society, suggested that their members count, rather than kill, the birds they encountered.
This concept was refined over the years to generate a census of birds across the country. The body of information is huge and valuable. It has become respected by scientists as an overview, or "snapshot" of the population of birds that would otherwise be impossible.
Beginning in 2006, Sieswerda conducted a similar annual survey to count the seals that were reported to be on Swinburne Island, a small man-made island just off the east coast of Staten Island. Having observed the expansion of seals into Massachusetts waters during his tenure at the New England Aquarium, he was intrigued by wildlife so close to urban centers.
New York City represents the epitome of human development and to see marine mammals so close to one of the world's great cities, deserved study. Annual counts established that seals were consistently returning to Swinburne every year in growing numbers. Upon his retirement in 2009 Sieswerda joined American Princess Cruises