Southern Hemisphere humpback whales wintering off Central America: insights from water temperature into the longest mammalian migration

Abstract

We report on a wintering area off the Pacific coast of Central America for humpback whales (Megaptera novaeangliae) migrating from feeding areas off Antarctica. We document seven individuals, including a mother/calf pair, that made this migration (approx. 8300km), the longest movement undertaken by any mammal. Whales were observed as far north as 11 degrees N off Costa Rica, in an area also used by a boreal population during the opposite winter season, resulting in unique spatial overlap between Northern and Southern Hemisphere populations. The occurrence of such a northerly wintering area is coincident with the development of an equatorial tongue of cold water in the eastern South Pacific, a pattern that is repeated in the eastern South Atlantic. A survey of location and water temperature at the wintering areas worldwide indicates that they are found in warm waters (21.1-28.3 degrees C), irrespective of latitude. We contend that while availability of suitable reproductive habitat in the wintering areas is important at the fine scale, water temperature influences whale distribution at the basin scale. Calf development in warm water may lead to larger adult size and increased reproductive success, a strategy that supports the energy conservation hypothesis as a reason for migration.

Aerial behavior of humpback whales Megaptera novaeangliae at the southern limit of the southeast Pacific breeding area

“…In the Southeast Pacific, humpback whales feed in Antarctic and Magellan waters (Acevedo et al 2007) and breed near islands and coastal areas off Ecuador (Félix & Haase 2001, 2005, Colombia (Stone et al 1990, Flórez-González 1991 and as far north as off Panama and Costa Rica (Flórez-González et al 1998, Rasmussen et al 2007). The northern coast of Peru (from the southern limit with Ecuador at ~3°S to ~6°S) is an interesting zone as it may represent the southern limit of the reproductive area (Pacheco et al 2009, Santillan 2011, Castro et al 2011, but also the transition passage from coastal breeding waters to the open oceanic realm used during migration (Félix & Haase 2005).…”

Identification of humpback whale breeding and calving habitat in the Great Barrier Reef

“…Humpback whales Megaptera novaeangliae are a highly mobile, migratory species that annually undertakes seasonal migrations from temperate or subpolar feeding areas in high latitudes to tropical breeding and calving habitat in low latitudes (Dawbin 1966). This migration is the longest known for any mammal (Rasmussen et al 2007, Stevick et al 2011 and represents a very distinct temporal and geographic separation of activities on an annual cycle, resulting in whales inhabiting very disparate environments over the year. Although their migration can occur over deep oceanic waters, humpback whales are typically a coastal species when feeding and breeding.…”

Movements and Timing of Humpback Whales (Megaptera novaeangliae) Within the Breeding Region of the Eastern South Pacific

“…Eastern South Pacific humpback whales (Megaptera novaeangliae) (Breeding Stock G, according to the International Whaling Commission [IWC], 1998) migrate from feeding grounds located mainly in the surroundings of the Antarctic Peninsula (Dalla and to a lesser extent in the Magellan Strait (Gibbons et al, 2003;Acevedo et al, 2006Acevedo et al, , 2013 and Golfo de Corcovado in southern Chile (HuckeGaete et al, 2013) to their breeding region off northern Peru, Ecuador, Colombia, Panama, and Costa Rica (Flórez-González, 1991;Flórez-González et al, 1998;Félix & Haase, 2001;Rasmussen et al, 2007;Pacheco et al, 2009;Guidino et al, 2014;Guzmán et al, 2015). The connectivity between some feeding and breeding grounds has been demonstrated through photoidentification (Stone et al, 1990;Stevick et al, 2004;Acevedo et al, 2007;Rasmussen et al, 2007;Capella et al, 2008) and to a lesser extent with genetics (Caballero et al, 2001;Félix et al, 2012).…”

“…The connectivity between some feeding and breeding grounds has been demonstrated through photoidentification (Stone et al, 1990;Stevick et al, 2004;Acevedo et al, 2007;Rasmussen et al, 2007;Capella et al, 2008) and to a lesser extent with genetics (Caballero et al, 2001;Félix et al, 2012). In addition, regional movements of five individuals and a migratory path used by one humpback whale from the breeding region to feeding grounds has been recently characterized via satellite tracking (Félix & Guzmán, 2014).…”