The daily and seasonal patterns of behavior and abundance of humpback whales (Megaptera novaeangliae) in Hawaiian waters. - Helweg, D.A.
University of Hawaii, Kewalo Basin Marine Mammal Lboratory, 1129 Ala Moana Blvd., Honolulu, HI, USA, 96814 -
- (C) 1989 University of Hawaii
This field study provides data that reveal the temporal patterns of the behavior and distribution of humpback whales (Megaptera novaeangliae) in Hawaiian waters. Observations of whale distribution and behavior were collected during the months of January to April in 1987 and 1988 from elevated shore stations on Maui and Hawaii, using scan sampling and focal observation Acoustic data were gathered from January to June, 1988 from a fixed hydraphone off the west coast of Kauai.
The rates of respirations , headlunging, and lateral fluke displays increased across the day. The rate of resting and no-blow rises were high at 0700. The noon sample was characterized by high rates of behaviors that involve slapping the surface, such as headslaps, fluke slaps and peduncle slaps. The modal size of pods with calves increased from two to three between 0700 and 0900, indicating that calf pods were not likely to be escorted early in the morning. Singing was heard day and night with a midmorning peak in the number singers. The percentage of pods with three or more adults increased across the day. This data suggests that the whales were resting in the predawn hours and that male-male competition peaked in the late afternoon.
The percentage of pods with calves as one member increased across the season, but the total number of calves seen peaked in mid-March, after which the total number of calves declined. Pods with calves were first observed in the first week of February in 1987 and 1988. Numbers of pods and whales counted per hour effort peaked in the first two weeks of February, but observations without whale sightings suggest that the local peaks may shift from region to region. Seasonal changes in pod types suggest that mature males are prepared to compete for mating opportunities are limited by the number of estrous females.
Helweg, D.A. (1989). The daily and seasonal patterns of behavior and abundance of humpback whales (Megaptera novaeangliae) in Hawaiian waters. Unpublished master's thesis, University of Hawaii, Honolulu.
Back to Top Dolphin Programs | Whale Programs | Education Programs | Our Research | Resource Guide Copyright © 2002, The Dolphin Institute |
