scholarly journals Distribution and Abundance of the Eastern Canada – West Greenland Bowhead Whale Population Based on the 2013 High Arctic Cetacean Survey

2020 ◽  
Vol 11 ◽  
Author(s):  
Thomas Doniol-Valcroze ◽  
Jean-François Gosselin ◽  
Daniel G. Pike ◽  
Jack W. Lawson ◽  
Natalie C. Asselin ◽  
...  
Keyword(s):  
High Arctic ◽  
Diving Behaviour ◽  
Bowhead Whale ◽  
Survey Area ◽  
Eastern Canada ◽  
West Greenland ◽  
Bowhead Whales ◽  
Abundance Estimate ◽  
Track Line ◽  
Canada West

The hunting of bowhead whales (Balaena mysticetus) is an integral part of Inuit culture. An up-to-date abundance estimate of the entire Eastern Canada – West Greenland (EC-WG) bowhead population is necessary to support sustainable management of this harvest. The High Arctic Cetacean Survey (HACS) was conducted in August 2013, primarily to update abundance estimates for known stocks of Baffin Bay narwhal (Monodon monoceros). As the ranges of narwhal and bowhead largely overlap, the survey area was expanded to cover the summer range of bowhead whales. Bowhead whale abundance was estimated using 3 aircraft to cover the large survey area within a short time frame. Distance sampling methods were used to estimate detection probability away from the track line. Double platform with mark-recapture methods were used to correct for the proportion of whales missed by visual observers on the track line (perception bias). Abundance in Isabella Bay, an area known for high bowhead density, was estimated using density surface modelling to account for its complex shape and uneven coverage. Estimates were corrected for availability bias (whales that were not available for detection because they were submerged when the aircraft passed overhead) using a recent analysis of satellite-linked time depth recorders transmitting information on the diving behaviour of bowhead whales in the study area in August of the same survey year. The fully corrected abundance estimate for the EC-WG bowhead whale population was 6,446 (95% CI: 3,838–10,827). Possible sources of uncertainty include incomplete coverage and the diving behaviour of bowhead whales. These results confirm earlier indications that the EC-WG stock is continuing to recover from past overexploitation.

Seasonal diving and foraging behaviour of Eastern Canada-West Greenland bowhead whales

2020 ◽  
Vol 643 ◽  
pp. 197-217 ◽  
Author(s):  
SME Fortune ◽  
SH Ferguson ◽  
AW Trites ◽  
B LeBlanc ◽  
V LeMay ◽  
...  
Keyword(s):  
Climate Change ◽  
Late Summer ◽  
Calanoid Copepods ◽  
Eastern Canada ◽  
West Greenland ◽  
Bowhead Whales ◽  
Seasonal Movement ◽  
Dive Behaviour ◽  
Calanus Glacialis ◽  
Canada West

Climate change may affect the foraging success of bowhead whales Balaena mysticetus by altering the diversity and abundance of zooplankton species available as food. However, assessing climate-induced impacts first requires documenting feeding conditions under current environmental conditions. We collected seasonal movement and dive-behaviour data from 25 Eastern Canada-West Greenland bowheads instrumented with time-depth telemetry tags and used state-space models to examine whale movements and dive behaviours. Zooplankton samples were also collected in Cumberland Sound (CS) to determine species composition and biomass. We found that CS was used seasonally by 14 of the 25 tagged whales. Area-restricted movement was the dominant behaviour in CS, suggesting that the tagged whales allocated considerable time to feeding. Prey sampling data suggested that bowheads were exploiting energy-rich Arctic copepods such as Calanus glacialis and C. hyperboreus during summer. Dive behaviour changed seasonally in CS. Most notably, probable feeding dives were substantially shallower during spring and summer compared to fall and winter. These seasonal changes in dive depths likely reflect changes in the vertical distribution of calanoid copepods, which are known to suspend development and overwinter at depth during fall and winter when availability of their phytoplankton prey is presumed to be lower. Overall, CS appears to be an important year-round foraging habitat for bowheads, but is particularly important during the late summer and fall. Whether CS will remain a reliable feeding area for bowhead whales under climate change is not yet known.

Occurrence of killer whale Orcinus orca rake marks on Eastern Canada-West Greenland bowhead whales Balaena mysticetus

Polar Biology ◽  
2013 ◽  
Vol 36 (8) ◽  
pp. 1133-1146 ◽  
Author(s):  
N. R. Reinhart ◽  
S. H. Ferguson ◽  
W. R. Koski ◽  
J. W. Higdon ◽  
B. LeBlanc ◽  
...  
Keyword(s):  
Killer Whale ◽  
Orcinus Orca ◽  
Balaena Mysticetus ◽  
Eastern Canada ◽  
West Greenland ◽  
Bowhead Whales ◽  
Canada West

scholarly journals Increasing abundance of bowhead whales in West Greenland

2007 ◽  
Vol 3 (5) ◽  
pp. 577-580 ◽  
Author(s):  
Mads Peter Heide-Jørgensen ◽  
Kristin Laidre ◽  
David Borchers ◽  
Filipa Samarra ◽  
Harry Stern
Keyword(s):  
Survey Design ◽  
Large Population ◽  
Aerial Survey ◽  
Bowhead Whale ◽  
West Greenland ◽  
Threshold Size ◽  
Bowhead Whales ◽  
Abundance Estimate ◽  
Surface Time ◽  
Severe Reduction

In April 2006, a dedicated survey of bowhead whales ( Balaena mysticetus ) was conducted on the former whaling ground in West Greenland to determine the current wintering population abundance. This effort included a double platform aerial survey design, satellite tracking of the movements of nine whales, and estimation of high-resolution surface time from 14 whales instrumented with time–depth recorders. Bowhead whales were estimated to spend an average of 24% (cv=0.03) of the time at or above 2 m depth, the maximum depth at which they can be seen on the trackline. This resulted in a fully corrected abundance estimate of 1229 (95% CI: 495–2939) bowhead whales when the availability factor was applied and sightings missed by observers were corrected. This surprisingly large population estimate is puzzling given that the change in abundance cannot be explained by a recent or rapid growth in population size. One possible explanation is that the population, which demonstrates high age and sex segregation, has recently attained a certain threshold size elsewhere, and a higher abundance of mature females appears on the winter and spring feeding ground in West Greenland. This in combination with the latest severe reduction in sea ice facilitating access to coastal areas might explain the surprising increase in bowhead whale abundance in West Greenland.

scholarly journals Developing a Precautionary Management Approach for the Eastern Canada-West Greenland Population of Bowhead Whales (Balaena mysticetus)

2021 ◽  
Vol 8 ◽  
Author(s):  
Steven H. Ferguson ◽  
Jeff W. Higdon ◽  
Patricia A. Hall ◽  
Rikke Guldborg Hansen ◽  
Thomas Doniol-Valcroze
Keyword(s):  
Population Size ◽  
Carrying Capacity ◽  
Population Increase ◽  
Balaena Mysticetus ◽  
Eastern Canada ◽  
Model Estimate ◽  
Management Framework ◽  
West Greenland ◽  
Bowhead Whales ◽  
Canada West

Bowhead whales (Balaena mysticetus L., 1758) of the Eastern Canada-West Greenland population have been hunted by Inuit for millennia. Significant commercial harvests, conducted by European and American whalers for about 400 years, ended ca. 1915. A small co-managed subsistence harvest from this population has occurred inconsistently in Canada and Greenland, since 1996 and 2009, respectively. Since near extirpation from commercial whaling, population size has increased and the Inuit subsistence hunt now requires a harvest management framework that incorporates knowledge of abundance trends, population dynamics, and carrying capacity. Here, we use a model estimate of pre-commercial exploitation abundance to approximate carrying capacity and develop a management framework with reference points and corresponding stock status zones. When applied to recent abundance estimates, our framework indicates that the population is likely within the healthy (N50–N70) zone. Thus, an appropriate management objective is to support continued population increase, with concurrent marginal harvesting, while maintaining the population level above the target reference point (N70) of ca 12,000 whales. However, there remains large uncertainty about current population size and growth rate. The resulting data gaps require a plan for future research to monitor this population in the context of climate changes.

Recaptures of genotyped bowhead whales Balaena mysticetus in eastern Canada and West Greenland

2011 ◽  
Vol 14 (3) ◽  
pp. 235-242 ◽  
Author(s):  
Ø Wiig ◽  
MP Heide-Jørgensen ◽  
C Lindqvist ◽  
KL Laidre ◽  
LD Postma ◽  
...  
Keyword(s):  
Balaena Mysticetus ◽  
Eastern Canada ◽  
West Greenland ◽  
Bowhead Whales

scholarly journals Three recent ice entrapments of Arctic cetaceans in West Greenland and the eastern Canadian High Arctic

2002 ◽  
Vol 4 ◽  
pp. 143 ◽  
Author(s):  
MP Heide-Jørgensen ◽  
P Richard ◽  
M Ramsay ◽  
S Akeeagok
Keyword(s):  
North Atlantic ◽  
Polar Bear ◽  
Canadian Arctic ◽  
High Arctic ◽  
Bowhead Whale ◽  
Delphinapterus Leucas ◽  
Polar Bears ◽  
Canadian High Arctic ◽  
West Greenland ◽  
The One

Three ice entrapments of Monodontids have been reported in the western North Atlantic since 1993. Hunters in Disko Bay, West Greenland, discovered one in March 1994 that included about 150 narwhals (Monodon monoceros). The entrapment occurred during a sudden cold period which caused ice to form rapidly. The trapped whales were subject to hunting, but about 50 of the killed whales could not be retrieved in the ice. The whales were trapped in a small opening in the ice and because of that they would probably have succumbed even if not discovered by hunters. Two entrapments involving white whales or belugas (Delphinapterus leucas) occurred in the eastern Canadian Arctic in May 1999; one in Lancaster Sound discovered by polar bear (Ursus maritimus) researchers and one in Jones Sound discovered by hunters. The first included one bowhead whale (Balaena mysticetus) and about 40 belugas that were being preyed upon by polar bears. The second involved at least 170 belugas, of which about 100 were killed by polar bears and 17 were taken by hunters. The entrapments in Disko Bay and Jones Sound both occurred in areas where entrapments have previously been reported, whereas the one in Lancaster Sound was in a new area.

scholarly journals Size and trends of the bowhead whale, beluga and narwhal stocks wintering off West Greenland

2002 ◽  
Vol 4 ◽  
pp. 191 ◽  
Author(s):  
MP Heide-Jørgensen ◽  
Mario Acquarone
Keyword(s):  
Bowhead Whale ◽  
Delphinapterus Leucas ◽  
Line Transect ◽  
Total Abundance ◽  
West Greenland ◽  
Bowhead Whales ◽  
Line Transect Survey ◽  
Monodon Monoceros ◽  
Northern Edge ◽  
Index Estimate

To assess the size and trends of the abundance of the bowhead whale (Balaena mysticetus), the beluga, or white whale (Delphinapterus leucas), and the narwhal (Monodon monoceros) visual aerial surveys were conducted in West Greenland in March 1998 and 1999. An estimated 49 bowhead whales (95% CI: 13 to 188) were present at the surface in 1998. Data from land-based observations enabled correction for bowhead whales that were not available at the surface to be seen during the survey. By applying a rounded average of 80% (SE=3) for submergence an estimate of 246 bowhead whales (95% CI: 62 to 978) in 1998 was obtained. The 76 and 47 sightings of beluga pods in 1998 and 1999, respectively, had distributions similar to those of previous surveys with the highest concentration at the northern edge of the northern part of Store Hellefiskebanke. No belugas were seen in the southernmost area between Maniitsoq and Paamiut. The index estimate of the abundance of belugas comparable with previous surveys was 929 (95% CI: 563 to 1,533) in 1998 and 735 (95% CI: 436 to 1,239) in 1999. When analysing the sightings as a line-transect survey and correcting for whales that were either submerged or at the surface but missed by the observers an estimated 7,941 (95% CI: 3,650 to 17,278) belugas wintered in West Greenland in 1998-1999. The uncorrected estimate of narwhal abundance was 524 (95% CI: 214 to 1,284) and correcting for the same biases as for the belugas gives a total abundance of 2,861 (95% CI: 954 to 8,578) narwhals in 1998-1999.

scholarly journals The Northwest Passage opens for bowhead whales

2011 ◽  
Vol 8 (2) ◽  
pp. 270-273 ◽  
Author(s):  
Mads Peter Heide-Jørgensen ◽  
Kristin L. Laidre ◽  
Lori T. Quakenbush ◽  
John J. Citta
Keyword(s):  
Sea Ice ◽  
High Arctic ◽  
Arctic Sea Ice ◽  
Canadian High Arctic ◽  
West Greenland ◽  
Northwest Passage ◽  
Bowhead Whales ◽  
The Pacific ◽  
Arctic Sea ◽  
Two Populations

The loss of Arctic sea ice is predicted to open up the Northwest Passage, shortening shipping routes and facilitating the exchange of marine organisms between the Atlantic and the Pacific oceans. Here, we present the first observations of distribution overlap of bowhead whales ( Balaena mysticetus ) from the two oceans in the Northwest Passage, demonstrating this route is already connecting whales from two populations that have been assumed to be separated by sea ice. Previous satellite tracking has demonstrated that bowhead whales from West Greenland and Alaska enter the ice-infested channels of the Canadian High Arctic during summer. In August 2010, two bowhead whales from West Greenland and Alaska entered the Northwest Passage from opposite directions and spent approximately 10 days in the same area, documenting overlap between the two populations.

Sign in / Sign up

Export Citation Format

Share Document