Habitat use of humpback whales in Godthaabsfjord, West Greenland, with implications for commercial exploitation

Abstract

North Atlantic humpback whales migrate from breeding grounds to high latitude feeding areas to where individuals display large scale site fidelity. In Godthaabsfjord (Greenland), humpback whales are present from early spring to late autumn. To test for small scale site fidelity and occurrence, identification-photographs were collected from May to September 2007 and 2008 and compared with an older catalogue. We found high small scale site fidelity where 40% of the whales present in 2007 were resighted in 2008. The average resight rate from 1992 to 2008 was 30.2%. Individuals did not remain in the fjord the entire season and the time spent in the fjord was highly variable amongst individuals varying between 7-60% of the time from May to September. Individual humpback whales in the presence and absence of boats were tracked with a land-based theodolite to test for effects of whale watching on whale behaviour. Whale watch vessels were shown to significantly increase whale swimming speed, to shorten long dives and diminish the ratio between surfacings and long dives. It is concluded that the same foraging whales use this fjord system year after year, calling for regulation of whale watching and for consideration when discussing reopening the whaling of humpback whales in West Greenland.

Effects of whale watching on the activity budgets of humpback whales,Megaptera novaeangliae(Borowski, 1781), on a feeding ground

“…Whale‐watching activities occur both in the breeding (Avila, Correa, & Parsons, ; Morete, Bisi, & Rosso, ; Schaffar, Madon, Garrigue, & Constantine, ) and the feeding (Boye et al, ) grounds of whales. In the feeding grounds of SEAK, whales feed on abundant prey resources, including: Pacific herring, Clupea pallasii Valenciennes, 1847; capelin, Mallotus villosus (Müller, 1776); and euphasiids, primarily Euphausia pacifica , Hansen, 1911 (Chenoweth, Gabriele, & Hill, ; Dolphin, ).…”

“…The recent worldwide growth of whale watching has raised concerns about its effects on targeted cetacean populations (O'Connor, Campbell, Cortez, & Knowles, 2009). These activities can affect cetaceans' habitat use and social cohesion (Boye, Simon, & Madsen, 2010;Nowacek, Wells, & Solow, 2001), and can also acoustically mask their abilities to communicate with sound (Buckstaff, 2004;Scarpaci, Bigger, Corkeron, & Nugegoda, 2000). Short-term effects can consist of the alteration of movement behaviour, such as changes in path linearity (Christiansen, Rasmussen, & Lusseau, 2013a), diving pattern (Gordon, Leaper, Hartley, & Chappell, 1992;Richter, Dawson, & Slooten, 2003), and also respiration rate (Williams, Trites, & Bain, 2002).…”

Groups of related belugas (Delphinapterus leucas) travel together during their seasonal migrations in and around Hudson Bay

“…Finally, it is worth noting that we did not find evidence for fidelity to specific summer sites, as reported in some whales [51,52], including beluga [53]. If belugas showed site fidelity in the study area, we would have expected significant mean relatedness (R xy ) for the site category.…”

Climate change and marine mammals

“…Oshima et al (2010) found that home ranges of the same species in the Cananéia Estuary, Brazil, also showed great individual variability. Boye et al (2010) showed that although the same humpback whales use the Godthaabsfjord system, West Greenland, as a foraging area year after year, individuals did not remain in the fjord the entire season and the time spent in the fjord was highly variable amongst individuals.…”