Use of social sounds by humpback whales (Megaptera novaeangliae) in the Western Antarctic Peninsula feeding grounds

Antarctic humpback whales are recovering from near extirpation from commercial whaling. To understand the dynamics of this recovery and establish a baseline to monitor impacts of a rapidly changing environment, we investigated sex ratios and pregnancy rates of females within the Western Antarctic Peninsula (WAP) feeding population. DNA profiling of 577 tissue samples (2010–2016) identified 239 males and 268 females. Blubber progesterone levels indicated 63.5% of the females biopsied were pregnant. This proportion varied significantly across years, from 36% in 2010 to 86% in 2014. A comparison of samples collected in summer versus fall showed significant increases in the proportion of females present (50% to 59%) and pregnant (59% to 72%), consistent with demographic variation in migratory timing. We also found evidence of annual reproduction among females; 54.5% of females accompanied by a calf were pregnant. These high pregnancy rates are consistent with a population recovering from past exploitation, but appear inconsistent with recent estimates of WAP humpback population growth. Thus, our results will help to better understand population growth potential and set a current baseline from which to determine the impact of climate change and variability on fecundity and reproductive rates.

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Sex differences in site fidelity and migration of humpback whales (Megaptera novaeangliae) to the Hawaiian Islands

Canadian Journal of Zoology ◽

10.1139/z97-822 ◽

1997 ◽

Vol 75 (11) ◽

pp. 1923-1933 ◽

Cited By ~ 56

Author(s):

Alison S. Craig ◽

Louis M. Herman

Keyword(s):

Site Fidelity ◽

Hawaiian Islands ◽

High Energy ◽

Megaptera Novaeangliae ◽

Humpback Whales ◽

Low Latitude ◽

Wintering Area ◽

The Mean ◽

And Migration ◽

Feeding Grounds

Humpback whales (Megaptera novaeangliae) perform extensive seasonal migrations between high-latitude summer feeding grounds and low-latitude winter reproductive grounds. To investigate gender-related site fidelity to the Hawaiian Islands, an important wintering area for North Pacific humpback whales, photographically based resight histories of 224 females and 416 males observed in Hawai'i from 1976 through 1991 were compiled. Results indicated that the mean number of years in which they were seen was higher for males than for females, that the probability of an individual being resighted across years was higher for males than for females, and that more males than females were seen in consecutive years. Potential sources of bias favoring the photographic capture of males were considered, but none were judged to be significant contributors to the results obtained. It was proposed instead that not all females undertake or complete the migration to the winter grounds each year. Because of the high energy costs of migration and reproduction, some females may overwinter in high latitudes, while others may become pregnant en route to the area traditionally associated with breeding and return to the feeding grounds before arriving at the terminal winter destination.

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The diets of humpback whales (Megaptera novaeangliae) on the shelf and oceanic feeding grounds in the western North Pacific inferred from stable isotope analysis

Marine Mammal Science ◽

10.1111/j.1748-7692.2012.00617.x ◽

2012 ◽

Vol 29 (3) ◽

pp. E253-E265 ◽

Cited By ~ 4

Author(s):

Olga A. Filatova ◽

Briana H. Witteveen ◽

Anton A. Goncharov ◽

Alexei V. Tiunov ◽

Maria I. Goncharova ◽

...

Keyword(s):

Stable Isotope ◽

Stable Isotope Analysis ◽

North Pacific ◽

Western North Pacific ◽

Isotope Analysis ◽

Megaptera Novaeangliae ◽

Humpback Whales ◽

Feeding Grounds

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Local and migratory movements of humpback whales (Megaptera novaeangliae) satellite-tracked in the North Atlantic Ocean

Canadian Journal of Zoology ◽

10.1139/cjz-2013-0161 ◽

2014 ◽

Vol 92 (1) ◽

pp. 9-18 ◽

Cited By ~ 32

Author(s):

A.S. Kennedy ◽

A.N. Zerbini ◽

O.V. Vásquez ◽

N. Gandilhon ◽

P.J. Clapham ◽

...

Keyword(s):

Dominican Republic ◽

North Atlantic ◽

Gulf Of Maine ◽

North Atlantic Ocean ◽

Megaptera Novaeangliae ◽

Humpback Whales ◽

The North ◽

Breeding Grounds ◽

Multiple Feeding ◽

Feeding Grounds

North Atlantic humpback whales (Megaptera novaeangliae (Borowski, 1781)) migrate from high-latitude summer feeding grounds to low-latitude winter breeding grounds along the Antillean Island chain. In the winters and springs of 2008 through 2012, satellite tags were deployed on humpback whales on Silver Bank (Dominican Republic) and in Guadeloupe (French West Indies) breeding areas. Whales were monitored, on average, for 26 days (range = 4–90 days). Some animals remained near their tagging location for multiple days before beginning their northerly migration, yet some visited habitats along the northwestern coast of the Dominican Republic, northern Haiti, the Turks and Caicos islands, and off Anguilla. Individuals monitored during migration headed towards feeding grounds in the Gulf of Maine (USA), Canada, and the eastern North Atlantic (Iceland or Norway). One individual traveled near Bermuda during the migration. This study provides the first detailed description of routes used by North Atlantic humpback whales towards multiple feeding destinations. Additionally, it corroborates previous research showing that individuals from multiple feeding grounds migrate to the Antilles for the breeding season. This study indicates that North Atlantic humpbacks use an area broader than the existing boundaries of marine mammal sanctuaries, which should provide justification for their expansion.

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Ventilation and dive patterns of humpback whales, Megaptera novaeangliae, on their Alaskan feeding grounds

Canadian Journal of Zoology ◽

10.1139/z87-013 ◽

1987 ◽

Vol 65 (1) ◽

pp. 83-90 ◽

Cited By ~ 37

Author(s):

William Ford Dolphin

Keyword(s):

Megaptera Novaeangliae ◽

Humpback Whales ◽

Prey Patch ◽

Feeding Grounds ◽

Echo Sounder

Noncalf humpback whales in Frederick Sound, Alaska, were tracked for periods of up to 12.5 h during July through September 1982, 1983, and 1984. Ventilation and dive patterns in presumably undisturbed humpback whales were characterized for six behaviors. Humpbacks appeared to restrict their dives to 150 m and rarely exceeded depths of 120 m, as determined by echo sounder tracings. Duration of dives and surfacings, number of blows per surfacing, and mean blow interval were positively correlated with the depth to which whales dived. Ventilation and dive variable values were significantly elevated in 1983 relative to 1982 and 1984. This was likely due to an increase in the depth of available prey during the 1983 season. The depth to which a feeding whale dove could be related to the depth of the target prey patch with greater than 84% accuracy based upon ventilation and dive variables.

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Earlier Sightings of Humpback Whales in Antarctica

Oryx ◽

10.1017/s0030605300018093 ◽

1982 ◽

Vol 16 (5) ◽

pp. 430-430

Author(s):

Peter Kinnear

Keyword(s):

Antarctic Peninsula ◽

West Coast ◽

Megaptera Novaeangliae ◽

Humpback Whales ◽

The West ◽

British Antarctic Survey ◽

The Antarctic

Nigel Bonner has documented sightings of humpbacks Megaptera novaeangliae off the west coast of the Antarctic Peninsula which seem to indicate some recovery of stocks (Oryx 16, 3: 231–232). It may therefore be worth placing on record the following sightings of this species made from Argentine Islands for 1970/72, when I was stationed at the British Antarctic Survey base.

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