Size‐and Age‐class Segregation of Bowhead Whales Summering in Northern Foxe Basin: A Photogrammetric Analysis

Cosens, Susan E.; Blouw, A.P.

doi:10.1111/j.1748-7692.2003.tb01109.x

Cited by 46 publications

(40 citation statements)

References 7 publications

(9 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Northern Foxe Basin is considered to represent nursing habitat and, as a result, more females with calves and juveniles are present (Finley 2001). Specific habitat requirements differ between sex/age/reproductive classes, as suggested by population segregation (Cosens & Blouw 2003. Bowhead whales are sexually dimorphic with females larger than males.…”

Section: Discussionmentioning

confidence: 99%

“…The Foxe Basin nursery area (Cosens & Blouw 2003) is characterized by shallow waters and spring ice cover, providing safe and relatively calm waters with predictable oceanographic processes suitable for nursing, in contrast to other segments of the population that tend to occupy coastal areas around Baffin Bay during spring (Finley 2001). As sea ice melts, whales are likely exposed to increased vulnerability to predation as killer whales enter the area (Dueck & Ferguson 2009).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Bowhead whale Balaena mysticetus seasonal selection of sea ice

Ferguson¹,

Dueck²,

Loseto³

et al. 2010

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Highly mobile large-bodied organisms are adapted to seasonal variation associated with polar environments. We used satellite tracking data from 27 bowhead whales Balaena mysticetus of the Eastern Canada-West Greenland population to test for movement and habitat selection of the highly variable sea ice landscape that encompasses near-complete coverage in winter to nearcomplete absence in summer. We demarcated 2 bowhead whale seasons based on movement behaviour identified from inflection points of polynomial regression analysis of movement rate: winter (28 December to 15 March, 16.6 ± 2.65 km d ). Resource selection functions were used to evaluate bowhead whale seasonal selection of sea ice landscape (coverage, thickness, and floe size). Movement and habitat use differed between Nunavut tagging sites likely as a consequence of sexual and reproductive segregation. Whales selected relatively low ice coverage, thin ice, and small floe areas in winter close to the maximum ice extent, presumably to reduce risk of ice entrapment while remaining within ice. In contrast, whales selected high ice coverage, thick ice, and large floe size areas in summer, presumably to reduce risk of killer whale predation while providing enriched feeding opportunities. Our results indicate that this largebodied animal can moderate use of the large-scale fluctuations in seasonal sea ice typical of polar environments.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Bowhead whale Balaena mysticetus seasonal selection of sea ice

Ferguson¹,

Dueck²,

Loseto³

et al. 2010

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

show abstract

“…First, measurements from aerial photographs could significantly increase our sample size of individually identified and measured seals, providing novel methods for mark-recapture studies. Second, high-resolution aerial photogrammetry cannot only be used to estimate length for acquiring a size distribution (e.g., Cubbage and Calambokidis 1987;Cosens and Blouw 2003); it can also be used to estimate mass. This will require significant calibration effort and development of quantitative models that relate standard measurements to mass.…”

Section: Leopard Seal Photogrammetrymentioning

confidence: 99%

A small unmanned aerial system for estimating abundance and size of Antarctic predators

et al. 2015

View full text Add to dashboard Cite

Quantifying the distribution and abundance of predators is integral to many ecological studies, but can be difficult in remote settings such as Antarctica. Recent advances in the development of unmanned aerial systems (UAS), particularly vertical takeoff and landing (VTOL) aircraft, have provided a new tool for studying the distribution and abundance of predator populations. We detail our experience and testing in selecting a VTOL platform for use in remote, windy, perennially overcast settings, where acquiring cloud-free high-resolution satellite images is often impractical. We present results from the first use of VTOLs for estimating abundance, colony area, and density of krilldependent predators in Antarctica, based upon 65 missions flown in 2010/2011 (n = 28) and 2012/2013 (n = 37). We address concerns over UAS sound affecting wildlife by comparing VTOL-generated noise to ambient and penguingenerated sound. We also report on the utility of VTOLs for missions other than abundance and distribution, namely to estimate size of individual leopard seals. Several characteristics of small, battery-powered VTOLs make them particularly useful in wildlife applications: (1) portability, (2) stability in flight, (3) limited launch area requirements, (4) safety, and (5) limited sound when compared to fixed-wing and internal combustion engine aircraft. We conclude that of the numerous UAS available, electric VTOLs are among the most promising for ecological applications.

show abstract

“…The abundance of bowhead whales in West Greenland was estimated at 1229 individuals (95% CI: 495-2939) in 2006 . Similarly, bowhead whales are found in large concentrations at specific locations in Foxe Basin, Northern Hudson Bay, in fjords along the east coast of Baffin Island and in the Canadian high Arctic during summer (Davis & Koski 1980, Finley 1990, Cosens & Innes 2000, Cosens & Blouw 2003. In winter, they tend to congregate in Hudson Strait, at the mouth of Cumberland Sound, along West Greenland, and in the North Water (HeideJørgensen et al 2007).…”

Section: Introductionmentioning

confidence: 99%

Large-scale sexual segregation of bowhead whales

Heide‐Jørgensen¹,

Laidre²,

Wiig³

et al. 2010

Endang. Species. Res.

View full text Add to dashboard Cite

Skin biopsy samples from 806 bowhead whales Balaena mysticetus collected between 1995 and 2010 at 4 locations in Nunavut, Canada, and at 1 locality in West Greenland were used for determination of sex and sexual segregation of bowhead whales in the Baffin Bay stock. There was a significant dominance of females in the Disko Bay samples (78%), whereas the sex ratio in aggregations in Nunavut was not significantly different from 50:50. Data on the body length of whales suggest that primarily large mature whales without calves occupy Disko Bay, whereas primarily mothercalf pairs are found in Foxe Basin. On a broader scale, Baffin Bay is more widely used by adult males and resting or pregnant females from Disko Bay, while Prince Regent, Gulf of Boothia, Foxe Basin, and northwestern Hudson Bay are also used by nursing females, calves, and sub-adults. The most parsimonious explanation for the large-scale spatial segregation of sexes in bowhead whales is that mature females without calves utilize Disko Bay as a foraging ground during certain parts of their reproductive cycle. Acoustic recordings of singing males indicate that Disko Bay may also be a mating ground, where some males may be following estrous females into the bay.

show abstract

Size‐and Age‐class Segregation of Bowhead Whales Summering in Northern Foxe Basin: A Photogrammetric Analysis

Cited by 46 publications

References 7 publications

Bowhead whale Balaena mysticetus seasonal selection of sea ice

Bowhead whale Balaena mysticetus seasonal selection of sea ice

A small unmanned aerial system for estimating abundance and size of Antarctic predators

Large-scale sexual segregation of bowhead whales

Contact Info

Product

Resources

About