Distribution and movements of West Indian humpback whales in winter

Abstract

The humpback whales which winter in the West Indies are principally found over banks which are at latitudes between 10° and 22° N, have substantial areas of flat bottom between 15 and 60 m deep, and lie less than 30 km from the North Atlantic 2000 m contour. The surface sea temperatures in these areas are between 24 and 28 °C. The major concentrations of the humpbacks, which feed little in winter, are on Silver and Navidad banks. On Silver Bank the humpback and humpback song densities peak in the centre of the Bank. Mothers with calves are generally found in areas of calm water, and singers are found over areas with a flat bottom, where they meander slowly. Larger groups move considerably faster and in straighter lines. There is no evidence of whales possessing particular movement patterns, preferred ranges, or territories within the Bank. The concentration of humpbacks may be a significant feature for other humpbacks.

Underwater topography determines critical breeding habitat for humpback whales near Osa Peninsula, Costa Rica: implications for Marine Protected Areas

“…Both preferences are consistent with the average characteristics of the entire study area, and with the affiliation to continental shelf's depths and contours that distribution of humpback whales exhibit as a general pattern reported elsewhere (Caldwell et al 1970, Whitehead and Moore 1982, Mattila and Clapham 1989, Mignucci-Giannoni 1998, Acevedo 2001, Félix and Haase 2001, Acevedo et al 2003, Swartz et al 2003, Frantzis et al 2004, Kaschner 2004, Félix and Haase, 2005: that is, concentrating on or along the edges of shallow banks and islands (Silva et al 2006) like Caño island, in areas less than 200 m deep, with fewer whales found in deep water. in the southern Pacific coast of Ecuador, humpbacks are rarely seen offshore in breeding season, seeking depths less than 60m (Félix and Haase 2005).…”

“…However, the time overlap is rare, since females with calves and competitive male groups were never seen at the same time. For instance, distribution of male singers seemed to follow a similar pattern described by Whitehead and Moore (1982), they report singers in shallow isothermal water over to smooth bottom, where song propagation will be virtually bi-dimensional. However, singers elsewhere had been located on deep waters (Frankel et al 1995), where offshore locations provide different acoustics propagation conditions.…”

“…Generally whales' distribution is restricted to waters of less than 100 fathoms (183m) deep. Records of breeding whales, particularly singing males, have been gathered in open deep waters, sometimes beyond the shelf break (Caldwell et al 1970, Whitehead and Moore 1982, Mattila and Clapham 1989, Mignucci-Giannoni 1998, Felix and Haase 2001, Acevedo et al 2003, Swartz et al 2003, Frantzis et al 2004, Kaschner 2004, Felix and Haase 2005. At a basin scale, Rasmussen et al (2007) identified a correlation on breeding sites in Central America with the occurrence of warm waters north of the equator (24 ˚C -28 ˚C) as opposed to coastal upwelling and cold tongue development during the austral winter, which create cool surface waters that will extend from the South American coast into the eastern equatorial Pacific.…”

Near-shore distribution of Heaviside’s (Cephalorhynchus heavisidii) and dusky dolphins (Lagenorhynchus obscurus) at the southern limit of their range in South Africa

“…In another part of this study, Heaviside's dolphins were found to move offshore at night, where they are thought to feed on vertically migrating prey (Sekiguchi et al 1992), and to spend daylight hours (when the data used in this study were collected) closer to shore resting and not feeding (Elwen et al 2006). In animals that are not feeding, influences on distribution can be far less clear, but most evidence suggests, that when resting or otherwise unengaged, cetaceans choose environments that are safe, from both predators and harsh environmental conditions (Whitehead & Moore 1982;Smultea 1994;Elwen & Best 2003;Lammers 2004;Heithaus & Dill 2006). Thus, even though Heaviside's dolphins appear not to be feeding while close inshore, they may still exhibit a preference for certain habitat types where predation risk is lower (inshore generally) or conditions are more conducive to resting and socializing.…”

A review of marine mammal records of Cuba

“…During winter, most of the North Atlantic population is believed to migrate south to calving grounds in the West Indies (Winn et al, 1975;Whitehead and Moore, 1982;Stevick et al, 1998;Smith et al, 1999). Most humpbacks are found in this region from January through March, with some animals arriving as early as November and a few remaining in the area until June (Erdman et al, 1973;Winn et al, 1975; Katona and Beard, 1991;Reeves et al, 2001).…”