Baleen whales and their prey in a coastal environment

1989 ◽  
Vol 67 (6) ◽  
pp. 1523-1530 ◽  
Author(s):  
John F. Piatt ◽  
David A. Methven ◽  
Alan E. Burger ◽  
Ruth L. McLagan ◽  
Vicki Mercer ◽  
...  
Keyword(s):  
Environmental Parameters ◽  
Abundance Ratio ◽  
Coastal Environment ◽  
Strongly Correlated ◽  
Balaenoptera Acutorostrata ◽  
Mallotus Villosus ◽  
Balaenoptera Physalus ◽  
Baleen Whales ◽  
Intermediate Depth ◽  
Capelin Mallotus Villosus

Patterns of abundance of humpback (Megaptera novaeangliae), fin (Balaenoptera physalus), and minke (Balaenoptera acutorostrata) whales are described in relation to the abundance of their primary prey, capelin (Mallotus villosus), during 1982–1985 at Witless Bay, Newfoundland. The abundance ratio of the three whale species was 10:1:3.5, respectively. Abundance of all whale species was strongly correlated with abundance of capelin through each season and between years. Capelin abundance accounted for 63% of the variation in whale numbers in 1983 and 1984, while environmental parameters (e.g., water temperatures) accounted for little variance. The amount of capelin consumed by whales was small (< 2%) compared with the amount available. All three species overlapped temporally at Witless Bay, but spatial overlap was reduced as fins occurred primarily offshore, minkes primarily inshore, and humpbacks in bay habitats of intermediate depth.

Predicting Inshore Whale Abundance — Whales and Capelin off the Newfoundland Coast

1985 ◽  
Vol 42 (5) ◽  
pp. 976-981 ◽  
Author(s):  
Hal Whitehead ◽  
J. E. Carscadden
Keyword(s):  
Fishing Gear ◽  
Balaenoptera Acutorostrata ◽  
Short Term ◽  
Balaenoptera Physalus ◽  
Baleen Whales ◽  
Large Numbers ◽  
Class Strength ◽  
Capelin Mallotus Villosus ◽  
Abiotic Variables ◽  
Northeast Coast

Inshore abundance of baleen whales along the Newfoundland coasts changed considerably during the period 1973–83. In particular, large numbers of humpbacks were present along the northeast coast each summer between 1977 and 1980. This influx led to entrapment of whales in fishing gear. Counts of humpback (Megaptera novaeangliae), finback (Balaenoptera physalus), and minke (Balaenoptera acutorostrata) whales during standard surveys along the coast are used as indices of inshore abundance, and are related to the year-class strengths of capelin (Mallotus villosus), their major food in the Newfoundland region. Whales are found inshore when there are few immature capelin offshore. Minke whale distributions seem more closely related to the abundance of 1- to 2-yr-old, immature capelin, but humpback and finback whales are found inshore with low abundances of 2- to 3-yr-old, mainly immature capelin. We suggest that estimates of capelin year-class strength predicted from abiotic variables can be used to predict inshore whale abundance, at least 1 yr in advance. The extreme influx of humpbacks of the late 1970s is unlikely to recur in the short term. The analysis suggests that finback populations in the area are declining.

Net Entanglements of Baleen Whales in the Inshore Fishery of Newfoundland

1979 ◽  
Vol 36 (5) ◽  
pp. 521-528 ◽  
Author(s):  
J. S. Perkins ◽  
P. C. Beamish
Keyword(s):  
Key Words ◽  
Newfoundland And Labrador ◽  
Megaptera Novaeangliae ◽  
Humpback Whales ◽  
Balaenoptera Acutorostrata ◽  
Balaenoptera Physalus ◽  
Baleen Whales ◽  
Minke Whales ◽  
Capelin Mallotus Villosus ◽  
Inshore Waters

This paper documents net entrapments of baleen whales in the inshore waters of Newfoundland and Labrador. The species involved are principally minke whales (Balaenoptera acutorostrata) and humpback whales (Megaptera novaeangliae). Finback whales (Balaenoptera physalus) are also caught in nets but far less frequently. The timing of these entrapments corresponds with the spawning season for capelin (Mallotus villosus) on the beaches around the province. The magnitude and implications of this problem, both to the whales and the fisherman, are assessed. Key words: baleen whales, net entrapments, mortality assessment, capelin, Balaenoptera acutorostrata, B. physalus, Megaptera novaeangliae

Channel head dynamics: capelin (Mallotus villosus) aggregation in the tidally driven upwelling system of the Saguenay - St. Lawrence Marine Park's whale feeding ground

2002 ◽  
Vol 59 (2) ◽  
pp. 197-210 ◽  
Author(s):  
Yvan Simard ◽  
Diane Lavoie ◽  
François J Saucier
Keyword(s):  
Circulation Model ◽  
Feeding Strategies ◽  
Total Biomass ◽  
Balaenoptera Acutorostrata ◽  
Mallotus Villosus ◽  
Tidal Dynamics ◽  
Lawrence Estuary ◽  
Fin Whale ◽  
Capelin Mallotus Villosus ◽  
Tidally Driven

Capelin (Mallotus villosus) tridimensional distribution at the head of the Laurentian Channel in the St. Lawrence estuary was investigated using 38- and 120-kHz acoustic surveys in the summers of 1994, 1995, 1997, and 1998. The results are interpreted with the help of a high-resolution tridimensional tidal circulation model. Total biomasses were small (93–4583 t) and showed rapid fluctuations, whereas mesoscale distribution was more constant. Capelin tended to occupy the very end of the channel head, especially the slopes and shallows surrounding the basins. This pattern did not coincide with the krill distribution, but the two total biomass series were significantly correlated. Capelin tidal dynamics is characterized by herding of capelin against the channel head slopes by the starting flooding currents, followed by an upwelling over the sills and shallows during maximum flood currents, and a return to the channel by the surface outflow during ebb. Each side of the channel head has a distinct capelin retention tidal cycle involving passive advection, swimming, and the two-layer estuarine circulation. This capelin distribution and tidal dynamics closely match the local fin whale (Balaenoptera physalus) and minke whale (Balaenoptera acutorostrata) distributions observed from the whale-watching fleet and typical tidal feeding strategies at the channel head.

scholarly journals The diet of the minke whale in Greenland - A short review

2000 ◽  
Vol 2 ◽  
pp. 92 ◽  
Author(s):  
Pia Barner Neve
Keyword(s):  
Prey Item ◽  
Stomach Contents ◽  
Short Review ◽  
Coastal Areas ◽  
Minke Whale ◽  
Balaenoptera Acutorostrata ◽  
Mallotus Villosus ◽  
Minke Whales ◽  
Capelin Mallotus Villosus

Information on the diet of minke whales (Balaenoptera acutorostrata) in Greenland waters is reviewed. The knowledge is based on reports by whale catchers in Greenland, supplemented by limited scientific studies of stomach contents. The available material indicates that capelin (Mallotus villosus) is the predominant prey item in Greenland waters, particularly in coastal areas. In offshore areas, sand eel (Ammodytes spp) is consumed rather frequently, and krill (euphausids) appears to play a certain role in some areas or periods.

Observations on Three Species of Baleen Whales off Northern Newfoundland and Adjacent Waters

1977 ◽  
Vol 34 (9) ◽  
pp. 1436-1440 ◽  
Author(s):  
Judith Perkins ◽  
Hal Whitehead
Keyword(s):  
Key Words ◽  
Population Size ◽  
Geographical Distribution ◽  
Humpback Whales ◽  
Population Estimate ◽  
Balaenoptera Acutorostrata ◽  
Balaenoptera Physalus ◽  
Baleen Whales ◽  
Sailing Boat ◽  
Water Depths

Minke, Balaenoptera acutorostrata, finback, Balaenoptera physalus, and humpback whales, Megaptera novaeangliae, were observed off northern Newfoundland and southern Labrador between June and September 1975, principally from a sailing boat. Distributions for these species are recorded and correlated with water depths and distances from shore. Several isolated sounds, but no "songs," were recorded from humpback whales in Notre Dame Bay, where a population estimate was calculated based on a new method of photographic marking of individuals. Key words: baleen whales, geographical distribution, population size, photographic tagging

Corneal anatomy of marine mammals

1993 ◽  
Vol 71 (11) ◽  
pp. 2282-2290 ◽  
Author(s):  
M. T. Pardue ◽  
J. G. Sivak ◽  
K. M. Kovacs
Keyword(s):  
Marine Mammals ◽  
Equatorial Region ◽  
Balaenoptera Acutorostrata ◽  
Marine Habitat ◽  
Corneal Surface ◽  
Balaenoptera Physalus ◽  
Phoca Groenlandica ◽  
Minke Whales ◽  
Transmission Electron ◽  
Ultrathin Sections

The corneal anatomy of fin whales (Balaenoptera physalus), minke whales (Balaenoptera acutorostrata), harp seals (Phoca groenlandica), ringed seals (Phoca hispida), and bearded seals (Eriganthus barbatus) was examined to determine if marine mammals have evolved specialized corneas for life in a marine habitat. One to seven eyes of each species were analyzed: paraffin sections stained with haematoxylin and eosin for light microscopy; and ultrathin sections for transmission electron microscopy. All corneas contain the five typical mammalian layers: epithelium, Bowman's layer, stroma, Descemet's membrane, and endothelium. The corneas of these marine mammals are thicker than human corneas because of a thicker stromal layer. The other layers are thinner than those found in humans, except for the epithelial layer in the bearded seal and the cetaceans where it may provide extra protection for the eye during feeding behaviour. The epithelial cells in all corneas studied have an abundance of tonofilaments, which may strengthen the cells and distribute force across the corneal surface. No special organization of collagen fibrils was found in the stroma that would offer protection from ultraviolet radiation or glare for pinnipeds when on ice. The thickness of the sclera in the cetaceans may serve to hold the inner globe of the eye in an elliptical shape, while the thinning of the sclera in the equatorial region in pinnipeds may flatten the eye in air to reduce aerial myopia.

scholarly journals Early life growth is affecting timing of spawning in the semelparous Barents Sea capelin (Mallotus villosus)

2021 ◽  
pp. 102614
Author(s):  
Florian Berg ◽  
Samina Shirajee ◽  
Arild Folkvord ◽  
Jane Aanestad Godiksen ◽  
Georg Skaret ◽  
...  
Keyword(s):  
Early Life ◽  
Barents Sea ◽  
Mallotus Villosus ◽  
Capelin Mallotus Villosus ◽  
Timing Of Spawning

Nutrients and phytoplankton in three shallow, freshwater lakes of different tropic status in Western Australia

1981 ◽  
Vol 32 (4) ◽  
pp. 541 ◽  
Author(s):  
DM Gordon ◽  
CM Finlayson ◽  
AJ McComb
Keyword(s):  
Green Algae ◽  
Western Australia ◽  
Organic Phosphorus ◽  
Environmental Parameters ◽  
Strongly Correlated ◽  
Freshwater Lakes ◽  
Nitrogen And Phosphorus ◽  
Water Conductivity ◽  
Blue Green Algae ◽  
Nitrogen Concentrations

The trophic status of three shallow, freshwater lakes on the Swan coastal plain near Perth, Western Australia, was assessed from February 1975 to January 1976. Loch McNess is in a National Park, Lake Joondalup is in an area becoming urbanized, and Lake Monger is in a suburb near the centre of Perth. Monthly measurements were made of phytoplankton numbers and environmental parameters, including forms of nitrogen and phosphorus. Populations tended to be high when lake levels were low. Phytoplankton numbers were dominated by blue-green 'algae' in summer in each lake, with the lowest numbers in Loch McNess. Green algae were most prominent in autumn and winter. Diatoms were present at relatively lower numbers throughout the year. Phytoplankton numbers were strongly correlated with phosphorus levels, particularly for blue-green algae, and less so with nitrogen. Green algae were also strongly correlated with water conductivity. Nearly 80% of variance in phytoplankton numbers was accounted for in multiple linear regression by temperature, sunlight hours, depth, pH, conductivity and phosphate, organic phosphorus, ammonia, nitrate-nitrite, and organic nitrogen concentrations. Much of the variance was accounted for by the nutrients alone. Comparisons with data in the literature suggest that Lakes Joondalup and Monger are eutrophic by world standards, and are far more eutrophic than Loch McNess.

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