Spatial components of bowhead whale (Balaena mysticetus) distribution in the Alaskan Beaufort Sea

Bowhead whales (Balaena mysticetus) on their fall migration are exposed to oil exploration activities in the Alaskan Beaufort Sea. While previous research into the effect of industrial noise on whale behavior and distribution has noted significant responses, this research has often proceeded from a parametric statistical framework. To account for the presence of spatially autocorrelated and intercorrelated data, we propose a suite of spatial analysis techniques to assess the distribution of bowhead whales relative to oil exploration activities. Using random resampling techniques and Mantel tests, we analyzed the distribution of bowhead whales around active drilling rigs in 1993. Results from the resampling tests indicated that whales were distributed farther from the drilling rig than they would be under a random scenario. Results from the Mantel tests indicated that in 1993, the spatial pattern of bowhead whale distribution was highly correlated with distance from the drilling rig, indicating that the presence of the drilling rig resulted in a significant temporary loss in available habitat. These techniques offer a new perspective on spatial analysis in the marine realm.

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Satellite-monitored movements of radio-tagged bowhead whales in the Beaufort and Chukchi seas during the late-summer feeding season and fall migration

Canadian Journal of Zoology ◽

10.1139/z00-045 ◽

2000 ◽

Vol 78 (7) ◽

pp. 1168-1181 ◽

Cited By ~ 26

Author(s):

Bruce R Mate ◽

Gregory K Krutzikowsky ◽

Martha H Winsor

Keyword(s):

Shallow Water ◽

Late Summer ◽

Open Water ◽

Beaufort Sea ◽

River Delta ◽

Bowhead Whale ◽

Balaena Mysticetus ◽

Bowhead Whales ◽

Russian Waters ◽

Summer Feeding

From 30 August to 6 September 1992, we tagged 12 juvenile bowhead whales (Balaena mysticetus) with Argos satellite-monitored radio tags in the Canadian Beaufort Sea off the Mackenzie River Delta. Eight tags documented [Formula: see text]9820 km of movements between 392 locations during 111 whale-tracking days. The whales did not move in unison. Individual movements and average speeds (1.1-5.8 km/h) varied widely. One whale stayed in Mackenzie Bay for 23.5 d, while the rest stayed an average of only 2.4 d. The majority of locations for all whales were in shallow water: 65% at <50 m depth and 87% at <100 m depth. Seven whales went into water >100 m deep and four were in water >500 m deep. The whale with the longest record traveled [Formula: see text]3886 km to Siberia in 32.5 d, averaging 5.0 km/h. Its westerly route through the Beaufort and Chukchi seas was between 70° and 72°N and primarily in heavy ice ([Formula: see text]90% coverage), which was continuous west of 151°W. This whale's speed was faster, though not significantly, in heavy ice than in more open water. This is the first detailed documentation of the route and speed of a bowhead whale during its fall migration from Canadian to Russian waters.

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Observations of Beachcast Bowhead Whales (Balaena mysticetus) in the Southeastern Beaufort Sea and Amundsen Gulf, 1987–2016

The Canadian Field-Naturalist ◽

10.22621/cfn.v131i3.2028 ◽

2018 ◽

Vol 131 (3) ◽

pp. 270-279

Author(s):

Lois A. Harwood ◽

Ellen V. Lea ◽

Stephen A. Raverty ◽

Patricia A. Hall ◽

Erin Linn ◽

...

Keyword(s):

Beaufort Sea ◽

Bowhead Whale ◽

Grizzly Bears ◽

Balaena Mysticetus ◽

Adult Group ◽

Mature Adult ◽

Bowhead Whales ◽

Mature Adults ◽

Amundsen Gulf ◽

Summer Feeding

Each spring, most Bowhead Whales (Balaena mysticetus) of the Bering-Chukchi-Beaufort (BCB) population migrate to the Canadian Beaufort Sea and Amundsen Gulf for summer feeding. Occasionally, Inuvialuit hunters and others observe beachcast (stranded) or adrift Bowhead Whale carcasses. From 1987 to 2016, 26 such occurrences were recorded. Most (65%) were found by Inuvialuit hunters travelling on the land, with the majority (54%) reported during 2000–2006. Bowhead Whale carcasses were found widely distributed throughout the region, with twice as many in Amundsen Gulf (65%) compared with the southeastern Beaufort Sea (35%). It was possible to measure or estimate standard length for 17 of 26 specimens, and all were either provisional ‘subadults’ (7–9.5 m; n = 10; 59%) or provisional ‘mature adults’ (13–16 m; n = 7; 41%). The cause(s) of mortality was not determined for any of the specimens. Whales in the ‘subadult’ group were likely 1–4 years old, while the ‘mature adult’ group were likely mostly mature animals (~25 y), including some potentially very old (>100 y). There was evidence or direct observation of Polar Bears (Ursus maritimus) and/or Grizzly Bears (U. arctos) scavenging at 60% of the carcasses for which presence or absence of bears or bear sign (scats and/or tracks) was reported. It is important to continue to record incidental observations of beachcast Bowhead Whales, as this may enable stranding rates to be evaluated.

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Mitogenomics and the genetic differentiation of contemporary Balaena mysticetus (Cetacea) from Svalbard

Zoological Journal of the Linnean Society ◽

10.1093/zoolinnean/zlaa082 ◽

2020 ◽

Author(s):

Lutz Bachmann ◽

Andrea A Cabrera ◽

Mads Peter Heide-Jørgensen ◽

Olga V Shpak ◽

Christian Lydersen ◽

...

Keyword(s):

Genetic Differentiation ◽

High Throughput Sequencing ◽

Demographic History ◽

Bowhead Whale ◽

Recent Common Ancestor ◽

Mitochondrial Genomes ◽

Balaena Mysticetus ◽

Bowhead Whales ◽

Most Recent Common Ancestor ◽

Loop Region

Abstract Full mitochondrial genomes were assembled for 12 recently sampled animals from the Svalbard bowhead whale (Balaena mysticetus) stock via high-throughput sequencing data, facilitating analysis of the demographic history of the population for the first time. The Svalbard population has retained noticeable amounts of mitochondrial genome diversity despite extreme historical harvest levels. Haplotype and nucleotide diversities were similar to those estimated earlier for other bowhead whale populations. The reconstructed demographic history was in accordance with a boom–bust scenario, combining a slight Pleistocene population growth 25 000–35 000 years ago and a Holocene decline. Employing a mutation rate of 3.418 × 10–8 substitutions per site per year, the time to the most recent common ancestor for the mitochondrial genomes of the contemporary Svalbard bowhead whales was estimated to be 68 782 (54 353–83 216) years before the present. Based on 370 bp fragments of the D-loop region, significant genetic differentiation was detected between all extant bowhead whale populations across the circumpolar Arctic. Thus, the Svalbard bowhead whales can be regarded as a population with its own genetic legacy.

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