Individual humpback whales (Megaptera novaengliae) show a high degree of fidelity to sites within their summer feeding range in the North Atlantic; little exchange is observed between these areas. Within the North Atlantic, feeding concentrations of humpback whales are found in areas of high productivity extending from the north-east coast of the U.S.A. to the Barents Sea (Katona & Beard, 1990; Smith et al., 1999;). Individuals from all North Atlantic feeding aggregations are known to congregate on a common breeding area in the West Indies for mating and calving (Katona & Beard, 1990; Stevick, Øien et al., 1999).
|All photos copyright: ©Chiara G. Bertulli
It has been suggested that eastern and western North Atlantic humpback whales constitute separate stocks, though the specific boundaries of the two stocks and the extent of overlap have been controversial (see reviews by Mitchell & Reeves, 1983; Christensen, Haug & Øien, 1992). Humpback whales are known to occur in the Cape Verde Islands in winter (Hazevoet & Wenzel, 2000), consistent with an eastern breeding area, though no re-sightings from this area have been confirmed. Genetic analysis of nuclear markers revealed a low but significant degree of heterogeneity between samples collected off Iceland and those collected in the western North Atlantic (Valsecchi et al., 1997). Recent findings that animals from Norwegian waters are sighted later in the West Indies season than the mean for other areas (Stevick, Øien et al., 1999) suggests that feeding ground origin may influence timing of occurrence in the West Indies.
Current research objectives
- Determine the abundance of humpback whales in the Faxaflói population
An intensive photo-identification study designed to minimize violation of mark-recapture assumptions can help to minimize bias and maximize precision of population estimates
- Determine patterns of residency of humpback whales in the Faxaflói populations
Using the photo-ID data for each year, it is possible to examine the number of days individual whales and dolphins are re-sighted; minimum residency time (the number of days between first and last sightings within the same season); and re-sighting rate (the proportion of individual whales/dolphins identified on more than one day within the same season)
- Investigate the prevalence of cutaneous disorders in humpback whales of Faxaflói Bay
Skin diseases in free-ranging whales have been studied using a variety of research methods including photographic identification (photo-id) surveys. Thus, photo-identification techniques can be extended to record the prevalence of certain signs of disease in whales, and suggests that these methods could be used to complement other studies of disease in wild cetacean populations
- Investigate the presence of peduncle scarrings for entanglement scarification studies
Photographs of the caudal peduncle of humpback whales obtained aboard commercial whale watch boats operating in the coastal waters of Massachusetts, particularly within the Gerry E. Studds-Stellwagen National Marine Sanctuary (Stellwagen Bank), were used to evaluate rates and severity of entanglement. The purpose of this collaboration between the Faxaflói Cetacean Research project, Húsavík Research Centre and the Provincetown Centre for Coastal Studies is to use images of caudal peduncle scarrings to monitor entanglement rates to be able in the future to evaluate potential factors, such as age and sex, to affect entanglement risk