Rolf Hicker Nature Photography
Humpback Whale, Megaptera novaeangliae at MarineBio.org
, which occurs when one whale thrusts its head forcefully towards another whale in a threatening manner, are believed to be aggressive behaviors meant to ward off competitors. Males display this behavior most often to gain access to females. Many other behaviors including fluke slaps, flipper slaps, and headslaps have also been characterized, although their apparent functions are unknown. At least 3 different species of barnacles are commonly found on both the flippers and the body of humpback whales. It is also home for a species of
whale lice,
Cyamus boopis
Communication
The
"songs" of humpbacks
are made up of complex vocal patterns. All whales within a given area and season seem to use the same songs. However, the songs appear to change from one breeding season to the next. Scientists believe that only male humpbacks sing. While the purpose of the songs is not known, many scientists think that males sing to attract mates, or to communicate among other males of the pod.
The Pod
A Pod refers to a social group of whales. In Hawaii, humpback whales typically belong to pods consisting of 2-3 individuals, although pods as large as 15 individuals have been sighted. Scientists feel that whales belong to certain pods for relatively short periods of time. One type of pod that is especially interesting is the cow-calf pod. A cow-calf pod represents the longest association between individual whales. In this type of pod, the mother whale, the cow, remains with her calf for a year during which time she nurses the young whale. In may instances, cow-calf pods are accompanied by another adult known as an escort. Escorts can be of either sex, but are most often reported to be males. Escorts do not remain in the cow-calf pod for long periods of time, usually for only a few hours. There have been no reported sightings of whale pods which contain more than one calf, indicating that each young whale is given a great deal of individual attention and care. This fact, together with the fact that the normal breeding-cycle of a humpback whale is two years, helps to explain why recovery of humpback whale populations progresses so slowly.
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