COI Funded Project: Demographic Models for the North Atlantic Right Whale

Hal Caswell, Biology

Project Duration: 6/1/98-12/31/99
Key Words: Western North Atlantic, Right Whale, endangered species, population modeling, photo-identification

Proposed Research

The North Atlantic right whale is the most endangered of the large whales. Hunted to near extinction by the end of the 19th century, it has recovered only slowly since commercial whaling was eliminated in the 1930's. Its population numbers only about 300 individuals. We will develop a population model for right whales, based on data obtained in photographic identification surveys by the New England Aquarium. These models will categorize individuals by developmental stage (yearling, juvenile, reproductive adult, nonreproductive adult), and will be one of the few such models for any whale population. They will provide estimates of population growth rate, extinction probability, population structure, and the effects of possible management interventions.

We have recently documented an apparent decline in mean annual survival probability over the last 15 years. If it is real, this decline is sufficient to cause extinction of the population. It is critical to determine whether the apparent trend persists when stage structure is included in the model, and how it is affected by the differences among stages. Our research will provide this information.