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.

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.

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

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

Severe mutilation of a baleen whale in a longline fishery off the Brazilian coast

2015 ◽  
Vol 8 ◽  
Author(s):  
Flavia C.F. Pinheiro ◽  
Salvatore Siciliano ◽  
Jailson F. de Moura ◽  
Davi C. Tavares
Keyword(s):  
Atlantic Ocean ◽  
Minke Whale ◽  
Brazilian Coast ◽  
Fishing Gear ◽  
Longline Fishery ◽  
Baleen Whale ◽  
Balaenoptera Acutorostrata ◽  
Baleen Whales ◽  
South West ◽  
Longline Fisheries

The interaction between baleen whales and longline fisheries is poorly known worldwide and likely underestimated. This article presents one of the most severe scenarios of this interaction; an incident that resulted in the severe mutilation of the entire fluke of a whale and probably lead to its death. Considering the characteristic of the fluke, we strongly suggest that the fluke belonged to a small balaenopterid, most likely a dwarf minke whale (Balaenoptera acutorostrata). The episode reported here seems to be the first in its nature involving a baleen whale entangled in longline fishing gear off the Brazilian coast, and so, it represents, at the very least, the need for further investigation into the magnitude of such interactions in the south-west Atlantic Ocean.

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.

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.

Anadromous Sturgeons: Habitats, Threats, and Management

2007 ◽  
Keyword(s):  
South Carolina ◽  
Brackish Water ◽  
Data Sets ◽  
Water Interface ◽  
Atlantic Sturgeon ◽  
Gill Net ◽  
Large Numbers ◽  
Class Strength ◽  
Study Designs ◽  
Acipenser Oxyrinchus

<em>Abstract</em>.—The anadromous Atlantic sturgeon <em>Acipenser oxyrinchus</em> once supported an important commercial fishery throughout its range (northern Florida, USA, to Labrador, Canada). All surviving populations are apparently depleted, presumably due to overfishing, pollution, and dam construction. A complete moratorium on the fishery has been established in U.S. waters. Unfortunately, population status is unknown for nearly all systems. Several 1994–2001 data sets from South Carolina rivers were examined for their potential in development of recruitment (year-class abundance) indices. Because Atlantic sturgeon often begin leaving their natal systems at age 2, after which they occupy other systems and then presumably return to natal areas at sexual maturity several years later, a valid river-specific abundance index must be based on either age0–1 or adult fish. Working with three former commercial Atlantic sturgeon fishermen to collect adults in two rivers during the spring and fall of 1998 resulted in collection of only 39 fish in 13 nominal age-classes. In another river, 2 years of monthly sampling with multipanel, anchored gill nets and otter trawls at eight stations throughout the estuary produced only 31 juvenile Atlantic sturgeon. Neither of these study designs provided adequate sample sizes. However, sampling in a clean-bottom section at the freshwater–brackish water interface of the Edisto River with a modified drift gill net produced large numbers of small Atlantic sturgeon. More than 3,000 juveniles have been collected and tagged since 1994. The 1,331 nominal age-1 Atlantic sturgeon that were captured displayed a distinct bimodal length frequency distribution, supporting the hypothesis that there are both spring and fall spawning events. A period of record drought impeded sampling efforts during a portion of this study. However, when flows and bottom configurations allow nets to be fished at the freshwater–brackish water interface, the gears and methods employed in the Edisto River can produce an age-1 Atlantic sturgeon catch per unit effort that is high enough to be used in estimating relative year-class strength.

The Distribution and Density of Commercial Fisheries and Baleen Whales within the Stellwagen Bank National Marine Sanctuary: July 2001–June 2002

2003 ◽  
Vol 37 (1) ◽  
pp. 35-53 ◽  
Author(s):  
David N. Wiley ◽  
Just C. Moller ◽  
Kristin A. Zilinskas ◽  
David N. Wiley
Keyword(s):  
Interaction Potential ◽  
Marine Mammal ◽  
Otter Trawl ◽  
Environmental Damage ◽  
Commercial Fisheries ◽  
Fishing Gear ◽  
Potential Harm ◽  
Baleen Whales ◽  
Patterns Of Use ◽  
Spatial Analyst

Research in a national marine sanctuary provides the ability to monitor, assess and understand changes in, and threats to, the area. In July 2001, the Stellwagen Bank National Marine Sanctuary undertook a year-long study to quantify and map patterns of human and marine mammal use. Data were collected during monthly standardized shipboard surveys that bisected the Sanctuary at 5 km (2.5 nm) intervals. We used a subset of those data and ArcView's Spatial Analyst program to conduct an analysis of the density and distribution of fixed gear (trap and gillnet) fisheries, mobile gear (otter trawl and scallop dredge) fisheries and baleen whales. We used this to develop a “user geography” of the Sanctuary based on patterns of use and identify high use areas that might pose the risk of environmental damage. We also used ArcView to develop an index of Relative Interaction Potential (RIP) to identify where baleen whales might become entangled in fishing gear; a known threat within the Sanctuary. The RIP identified a number of areas that stood out in terms of entanglement risk. Information from the study will allow managers to identify future changes in Sanctuary use and investigate current areas of intense use for potential harm.

Using historical accounts to assess the occurrence and distribution of small cetaceans in a poorly known area

2010 ◽  
Vol 90 (8) ◽  
pp. 1583-1588 ◽  
Author(s):  
Cristina Brito ◽  
Nina Vieira
Keyword(s):  
Historical Data ◽  
Historical Science ◽  
13Th Century ◽  
Historical Sources ◽  
Baleen Whales ◽  
Delphinus Delphis ◽  
Large Numbers ◽  
Alternative Sources ◽  
Historical Accounts ◽  
Common Dolphins

Historical science may play an important role in helping understanding and shaping the future of the world's oceans and to comprehend present day effects and conditions. Regarding cetaceans, historical accounts may be extremely useful to add new data to their occurrence and distribution in poorly studied regions. In Portugal, historical sources indicate that toninhas (possibly common dolphins Delphinus delphis) were observed since the 13th Century and were captured in large numbers during the late 19th and 20th Centuries. Historical occurrences given by naturalists and scientific surveys conducted by biologists indicate their regular presence with particular preference for certain areas. Also, recent observations of opportunity resulted in the same kind of accounts. Between 1976 and 1978, a study on captured cetaceans along the Portuguese shore found at fish markets was conducted and resulted in a total count of 45 cetaceans. Most captures were of small cetaceans (87% common dolphins), even though four baleen whales were registered. These cetacean captures were part of a local non-industrial fishery, as they were not the main target, but rather opportunistic catches or even by-catches of other fisheries. Delphinids were not protected by law at the time and were caught with hand harpoons or accidentally drowned in fish nets, sometimes sold at major fish markets such as Sesimbra, Peniche and Póvoa de Varzim. In geographical areas where recent cetacean sightings are rare and information is sparse, such as Portugal, it becomes important to take advantage of alternative sources of data. Our contribution towards the compilation of relevant historical and ‘forgotten’ science such as old natural observations, whaling data and observations of opportunity stresses the relevance of using historical data to access past occurrence and distribution of cetaceans.

Exclusive adjoining ranges in individually identified minke whales (Balaenoptera acutorostrata) in Washington state

1983 ◽  
Vol 61 (1) ◽  
pp. 174-181 ◽  
Author(s):  
Eleanor M. Dorsey
Keyword(s):  
Washington State ◽  
Small Scale ◽  
Territorial Defense ◽  
Balaenoptera Acutorostrata ◽  
Marine Waters ◽  
Baleen Whales ◽  
Distinctive Features ◽  
Naturally Occurring ◽  
Minke Whales ◽  
Free Ranging

Free-ranging minke whales in the inland marine waters of Washington, U.S.A., were found to be individually identifiable from photographs of naturally occurring distinctive features. Sixteen individuals were recognized and observed from small boats 66 times over 3.5 months in 1980, and four of these whales were also recognized from photographs taken in 1977 and 1978. Three exclusive adjoining ranges were found in about 600 km2, each one shared by up to at least seven minke whales, with only two instances of crossover between areas in 70 sightings. Feeding was observed in all three areas, and the whales within each area appeared most of the time to be acting independently of one another. No calves were seen, and no overt acts of territorial defense were observed. This is the first known report in baleen whales of nonoverlapping ranges on a very small scale.

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