scholarly journals Bowhead Whale Distribution and Feeding near Barrow, Alaska, in Late Summer 2005–06

ARCTIC ◽  
2010 ◽  
Vol 63 (2) ◽  
Author(s):  
Sue E. Moore ◽  
J.C. "Craig" George ◽  
Gay Sheffield ◽  
Joshua Bacon ◽  
Carin J. Ashjian
Keyword(s):  
2018 ◽  
Vol 79 (2) ◽  
pp. 1-22
Author(s):  
Kim E. W. Shelden ◽  
Julie A. Mocklin ◽  
Kimberly T. Goetz ◽  
David J. Rugh ◽  
Linda Vate Brattström ◽  
...  

2000 ◽  
Vol 78 (7) ◽  
pp. 1168-1181 ◽  
Author(s):  
Bruce R Mate ◽  
Gregory K Krutzikowsky ◽  
Martha H Winsor

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.


2013 ◽  
Vol 134 (6) ◽  
pp. 4323-4334 ◽  
Author(s):  
Russell A. Charif ◽  
Ashakur Rahaman ◽  
Charles A. Muirhead ◽  
Michael S. Pitzrick ◽  
Ann M. Warde ◽  
...  

2016 ◽  
Vol 12 (9) ◽  
pp. 20160251 ◽  
Author(s):  
Sue E. Moore

The marine ecosystem in the Pacific Arctic region has experienced dramatic transformation, most obvious by the loss of sea ice volume (75%), late-summer areal extent (50%) and change in phenology (four to six weeks longer open-water period). This alteration has resulted in an opening of habitat for subarctic species of baleen whales, many of which are recovering in number from severe depletions from commercial whaling in the nineteenth and twentieth centuries. Specifically, humpback, fin and minke whales ( Megaptera novaeangliae , Balaenoptera physalus and Balaenoptera acutorostrata ) are now regularly reported during summer and autumn in the southern Chukchi Sea. These predators of zooplankton and forage fishes join the seasonally resident grey whale ( Eschrichtius robustus ) and the arctic-endemic bowhead whale ( Balaena mysticetus ) in the expanding open-ocean habitat of the Pacific Arctic. Questions arising include: (i) what changes in whale-prey production and delivery mechanisms have accompanied the loss of sea ice, and (ii) how are these five baleen whale species partitioning the expanding ice-free habitat? While there has been no programme of research specifically focused on these questions, an examination of seasonal occurrence, foraging plasticity and (for bowhead whales) body condition suggests that the current state of Pacific Arctic marine ecosystem may be ‘boom times’ for baleen whales. These favourable conditions may be moderated, however, by future shifts in ecosystem structure and/or negative impacts to cetaceans related to increased commercial activities in the region.


2014 ◽  
Vol 135 (3) ◽  
pp. 1641-1641
Author(s):  
Russell A. Charif ◽  
Ashakur Rahaman ◽  
Charles A. Muirhead ◽  
Michael S. Pitzrick ◽  
Ann M. Warde ◽  
...  

ARCTIC ◽  
2017 ◽  
Vol 70 (2) ◽  
pp. 161 ◽  
Author(s):  
Lois A. Harwood ◽  
Lori T. Quakenbush ◽  
Robert J. Small ◽  
J. Craig George ◽  
James Pokiak ◽  
...  

Each spring, most bowhead whales of the Bering-Chukchi-Beaufort (BCB) population migrate to the southeast Beaufort Sea and summer in Canadian waters. In August and September, they form aggregations, which are known to occur mainly in the shallow, shelf waters when oceanographic conditions promote concentration of their zooplankton prey. The movements of individual bowheads while they occupy these late summer habitats are less well known; our knowledge is based on photographic evidence and limited tagging studies conducted from 1982 to 2000. In this study, 85% (17) of the 20 satellite-tagged whales that could have spent some time in the Canadian portion of the Beaufort Sea during late summer 2006 to 2012 spent all or part of August and September there. We analyzed location data for 16 whales, using a two-state switching correlated random walk (CRW) behavioural model, and classified locations in the Canadian waters as associated with lingering behaviour (inferred foraging) or directed travel. We found that these whales spent the greatest proportion of their time lingering (59%), followed by traveling (22%), and transitioning between lingering and traveling (19%). Using only lingering locations for these tagged whales in all study years pooled, we calculated kernel densities and defined five areas within the 75% density contour as aggregation areas. Together, the five aggregation areas we defined comprised 25 341 km2, 14.1% of the total area used by these tagged whales in Canadian waters during August and September of the deployment years. Three aggregation areas were located in shallow waters of the Beaufort Sea Shelf and were used almost exclusively by immature tagged whales in our sample. Two other aggregation areas were observed, one in Darnley Bay and one in Viscount Melville Sound in the Canadian Arctic Archipelago. Each of these was used by one mature whale. Tagged whales were observed to use one or two aggregation areas in a single season, and rarely more. The proportion of lingering time spent in each aggregation area was highly variable among individuals. The largest aggregation area (10 877 km2), located over the Beaufort Shelf north of the Tuktoyaktuk Peninsula (5 – 52 m depth), was used by 13 of the 16 tagged whales, almost exclusively by the immature whales, including three of four that were tracked in two consecutive summers. The Beaufort Shelf overall (and possibly the Tuktoyaktuk Shelf, including the Outer Shelf, in particular) was especially important for immature bowhead whales, while mature whales used habitats beyond the Beaufort Shelf during late summer. Findings may be important to inform both decisions on management and mitigative actions relating to bowhead whale use of the Beaufort Shelf and studies that aim to improve our understanding of the prey base of BCB bowhead whales in the Canadian Beaufort Sea region.


2006 ◽  
Vol 36 (17) ◽  
pp. 12
Author(s):  
MICHAEL E. PICHICHERO
Keyword(s):  

2020 ◽  
Vol 643 ◽  
pp. 197-217 ◽  
Author(s):  
SME Fortune ◽  
SH Ferguson ◽  
AW Trites ◽  
B LeBlanc ◽  
V LeMay ◽  
...  

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.


Author(s):  
Majid Baserisalehi ◽  
Samira Zarezadeh ◽  
Majid Baserisalehi ◽  
Saeed Shoa

Stenotrophomonas maltophilia is an emerging pathogenic non-fermentative Gram-negative Bacillus species. It has caused many nosocomial infections and can be isolated from various hospital wards and healthcare facilities. Research has shown that most of its strains are inherently resistant to many antibiotics and have multidrug resistance. This research intended to determine its occurrence frequency at some Hospitals in shiraz, Iran. The present study was conducted in six months (from early spring to late summer 2019). Clinical samples (Blood, Urine and cerebrospinal fluid (CSF)) collected from 120 patients afflicted with various infections. The samples were transferred to the Laboratory and subjected to microbiological analysis. Identification of the isolates was carried out by phenotypic methods and Stenotrophomonas maltophilia isolates verified using molecular methods. In total, various bacteria were isolated from 84 clinical samples. The isolates were Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Stenotrophomonas maltophilia, Staphylococcus aureus and Pseudomonas aeruginosa. Stenotrophomonas maltophilia was isolated from 17 (20.2%) positive samples and most of them were isolated from blood samples. Our finding indicated that Stenotrophomonas maltophilia isolated more from blood samples follow by CSF sample. In addition, our finding illustrated that Stenotrophomonas maltophilia can be considered as the common nosocomial agent at hospitals in Shiraz, Iran.


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