Population characteristics of humpback whales in Glacier Bay and adjacent waters: 2001

Doherty, Janet; Gabriele, Christine

We photographically identified 97 individual humpback whales (Megaptera novaeangliae), including 12 mother/calf pairs, in Glacier Bay and Icy Strait between June 1 and August 31, 2001. This represents the second highest number of whales ever identified in the study area since 1985. In contrast, in Glacier Bay, the whale counts were at their lowest levels in over five years. The frequency of whale sightings in western Icy Strait was high while the number of whale sightings in the Lower Bay was low. The standardized count of 57 whales and the total count of 82 whales in Icy Strait are the highest whale counts ever documented in Icy Strait. Twenty-six percent (n = 25) of the whales we identified were of known age. The number of calves we observed (n = 12) is almost double the average number of calves (6.2) since 1982. The sex of three of the mothers we identified (#1014, #1479 and #1273) was not known previously. We have documented whale #1014, the 1989 calf of #236, every year in the study area since 1991 without a calf, making her 12 years old at the age of her first known reproduction. We observed whale #587, identified with a calf in May and August, without her calf in September. We documented the evolution of an unusual deformity on whale #564's flank. We found whale #68, a pregnant female, dead near Point Gustavus in July from multiple fractures of the skull. The nature and severity of her injuries and the investigations into the circumstances surrounding her death indicate that this individual died from a collision with a large ship.