Episodic Upwelling of Zooplankton within a Bowhead Whale Feeding Area near Barrow, AK

1. Factors controlling the distribution of the bird fleas Ceratophyllus styx, the sand-martin flea, C. gallinae, the hen flea, and Dasypsylla gallinulae, the blackbird flea, were investigated in the field.2. Sand-martin fleas (C. styx) pass the winter as adults within cocoons in the old nests of their host. Observations indicate that the fleas are stimulated to emerge from the cocoons by the rise in temperature in the spring, and some of the adult fleas emigrate in the spring and invade new nest burrows. Observations and experiments showed that sand-martin fleas disperse from old burrows both laterally and vertically and that emigrating fleas could reach areas as far as 33·8 m. from the old nests. The detection of the new burrow entrances is not due to vision, or to the recognition of difference of humidity between the burrow and the cliff face, or to the reaction to air current differences between the burrow and the cliff face, but to recognition of the horizontal floor of the burrows and a tendency to congregate upon horizontal surfaces. How the fleas distinguish the horizontal burrow surface from the cliff top is still unknown. The colonization of new burrows by the fleas does not occur at night. It is suggested that, in addition to finding their hosts in the spring by invading new burrows, sand-martin fleas may jump on to the birds when they are hovering near the cliff face. Many adult fleas leave the burrows within 3 days of the fledging time of the young sand-martins but a small number remain within the nest. The fate of these specimens is not known.3. C. gallinae, the hen flea, and D. gallinulae, the blackbird flea, pass the winter principally as adults enclosed in the cocoons in the old nest material. In the spring they emerge from the cocoons, emigrate away from the old nest and are free-living on the ground. Probably the adult C. gallinae and D. gallinulae jump on to birds when they are feeding on the ground in the spring.* Therefore the absence of hen fleas in nests situated on the ground or in open nests built in low vegetation, is not due to lack of opportunity of contact between the adult flea and the birds which construct such nests.4. It is concluded that in host-seeking, adults of C. gallinae and D. gallinulae emigrate away from old nests in the spring and come in contact with the host birds on the ground in the birds' feeding area, whereas C. styx adults emigrate into the hosts' breeding area and come in contact with the birds in the new nesting burrows.

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Olfaction and brain size in the bowhead whale (Balaena mysticetus)

Marine Mammal Science ◽

10.1111/j.1748-7692.2010.00406.x ◽

2010 ◽

Vol 27 (2) ◽

pp. 282-294 ◽

Cited By ~ 60

Author(s):

J. G. M. Thewissen ◽

John George ◽

Cheryl Rosa ◽

Takushi Kishida

Keyword(s):

Brain Size ◽

Bowhead Whale ◽

Balaena Mysticetus

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AGROTECNICAL SUBSTANTIATION OF THE SOWING METHOD AND WORKING BODIES OF THE GRAIN STUBBLE SEEDER

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2021/2/67-70 ◽

1970 ◽

pp. 67-70

Author(s):

D. N. Radnaev ◽

S. V. Petunov ◽

D-Ts. B. Badmatsyrenov

Keyword(s):

Wind Erosion ◽

Cutting Tools ◽

Conservation Agriculture ◽

Mineral Fertilizers ◽

Continuous Rolling ◽

Grain Crops ◽

Feeding Area ◽

The Republic ◽

The Arid Regions ◽

Working Bodies

The paper presents the results of studies of grain crops row sowing method agrotechnical indicators after the modernization of the working bodies of the SZS-2.1 seeder-cultivator. The SZS-2,1 stubble cultivator seeder has found wide application in the arid regions of the Republic of Buryatia, whose soils are prone to wind erosion. This seeder provides a combination of pre-sowing cultivation, sowing grain crops, applying mineral fertilizers to the sown rows and rolling them on stubble backgrounds, that is, in fields that have been processed since autumn with flat-cutting tools or have not been cultivated at all. Sowing with these seeders with 23 cm row spacing in a row method is the main method of sowing spring wheat in the soil conservation agriculture system. Routine sowing on soils of light texture, subject to wind erosion, causes thickening of plants in a row, which leads to irrational use of the feeding area by plants, increased weediness of crops between rows and, ultimately, to a decrease in yield. A distributor for the coulter has been developed, where the seeds are fed to the distributor. Then, reflecting from the distributor, the seeds are evenly dispersed in the opener under the plow space. Also, instead of serial wedge-shaped packer rollers, ring-spur rollers of the 3KSH-6 type are installed on the seeder. In addition, continuous rolling provides the necessary contact of seeds with the soil, preserves soil moisture and helps to attract it from the lower layers. Thus, the modernization of the SZS-2.1 seeder made it possible to substantiate subsurface-spread strip sowing with continuous rolling, which ultimately led to an increase in grain yield by 10-15%.

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Organization and distribution of glomeruli in the bowhead whale olfactory bulb

10.7287/peerj.preprints.740 ◽

2014 ◽

Author(s):

Takushi Kishida ◽

J. G. M. Thewissen ◽

Sharon Usip ◽

John C George ◽

Robert S Suydam

Keyword(s):

Olfactory Bulb ◽

Olfactory Receptor ◽

Olfactory Receptors ◽

Molecular Data ◽

Dorsal Side ◽

Bowhead Whale ◽

Model Organisms ◽

Marker Genes ◽

Baleen Whales ◽

Olfactory Receptor Genes

Although modern baleen whales still possess a functional olfactory systems that includes olfactory bulbs, cranial nerve I and olfactory receptor genes, their olfactory capabilities have been reduced profoundly. This is probably in response to their fully aquatic lifestyle. The glomeruli that occur in the olfactory bulb can be divided into two non-overlapping domains, a dorsal domain and a ventral domain. Recent molecular studies revealed that all modern whales have lost olfactory receptor genes and marker genes that are specific to the dorsal domain, and that a modern baleen whale possess only 60 olfactory receptor genes. Here we show that olfactory bulb of bowhead whales (Balaena mysticetus, Mysticeti) lacks glomeruli on the dorsal side, consistent with the molecular data. In addition, we estimate that there are more than 4,000 glomeruli in the bowhead whale olfactory bulb. Olfactory sensory neurons that express the same olfactory receptor in mice generally project to two specific glomeruli in an olfactory bulb, meaning that ratio of the number of olfactory receptors : the number of glomeruli is approximately 1:2. However, we show here that this ratio is not applicable to whales, indicating the limitation of mice as model organisms for understanding the initial coding of odor information among mammals.

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A description and summary of the Antarctic Humpback Whale Catalogue

J. Cetacean Res. Manage. ◽

10.47536/jcrm.vi.307 ◽

2020 ◽

pp. 95-99

Author(s):

Judith Allen ◽

Carole Carlson ◽

Peter T. Stevick

Keyword(s):

South America ◽

Southern Ocean ◽

Antarctic Peninsula ◽

Humpback Whale ◽

Humpback Whales ◽

Western Coast ◽

Long Distance ◽

Dorsal Fin ◽

Feeding Area ◽

The Antarctic

The Antarctic Humpback Whale Catalogue (AHWC) is an international collaborative project investigating movement patterns of humpback whales in the Southern Ocean and corresponding lower latitude waters. The collection contains records contributed by 261 researchers and opportunistic sources. Photographs come from all of the Antarctic management areas, the feeding grounds in southern Chile and also most of the known or suspected low-latitude breeding areas and span more than two decades. This allows comparisons to be made over all of the major regions used by Southern Hemisphere humpback whales. The fluke, left dorsal fin/flank and right dorsal fin/flank collections represent 3,655, 413 and 407 individual whales respectively. There were 194 individuals resighted in more than one year, and 82 individuals resighted in more than one region. Resightings document movement along the western coast of South America and movement between the Antarctic Peninsula and western coast of South America and Central America. A single individual from Brazil was resighted off South Georgia, representing the first documented link between the Brazilian breeding ground and any feeding area. A second individual from Brazil was resighted off Madagascar, documenting long distance movement of a female between non-adjacent breeding areas. Resightings also include two matches between American Samoa and the Antarctic Peninsula, documenting the first known feeding site for American Somoa and setting a new long distance seasonal migration record. Three matches between Sector V and eastern Australia support earlier evidence provided by Discovery tags. Multiple resightings of individuals in the Antarctic Peninsula during more than one season indicate that humpback whales in this area show some degree of regional feeding area fidelity. The AHWC provides a powerful non-lethal and non-invasive tool for investigating the movements and population structure of the whales utilising the Southern Ocean Sanctuary. Through this methodical, coordinated comparison and maintenance of collections from across the hemisphere, large-scale movement patterns may be examined, both within the Antarctic, and from the Antarctic to breeding grounds at low latitudes.

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MICROFLORA ASSOCIATED WITH THE SKIN OF THE BOWHEAD WHALE (BALAENA MYSTICETUS)

Journal of Wildlife Diseases ◽

10.7589/0090-3558-26.3.351 ◽

1990 ◽

Vol 26 (3) ◽

pp. 351-359 ◽

Cited By ~ 11

Author(s):

E. B. Shotts ◽

T. F. Albert ◽

R. E. Wooley ◽

J. Brown

Keyword(s):

Bowhead Whale ◽

Balaena Mysticetus

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