Surface foraging behaviour of the North Atlantic right whale, Eubalaena glacialis, and associated zooplankton characteristics

1990 ◽  
Vol 68 (10) ◽  
pp. 2214-2220 ◽  
Author(s):  
Charles A. Mayo ◽  
Marilyn K. Marx
Keyword(s):  
Foraging Behaviour ◽  
Rate Of Change ◽  
Calanus Finmarchicus ◽  
Cape Cod ◽  
North Atlantic Right Whale ◽  
Right Whale ◽  
The North ◽  
Cape Cod Bay ◽  
Zooplankton Density ◽  
Right Whales

Right whales in Cape Cod Bay, Massachusetts, were studied to determine the relationship between their surface feeding behaviour and the density and composition of their planktonic prey. The swimming path characteristics of whales feeding, socializing, and travelling were compared. Zooplankton samples collected in the feeding path were contrasted with those from areas where whales were not present. Surface prey patches where right whales fed were dominated by Calanus finmarchicus (21 samples), Pseudocalanus minutus (n = 13), Centropages sp. (n = 3), and larval barnacles (n = 2). The zooplankton density in the feeding path of the whales tested significantly higher (Mann–Whitney U-test, P < 0.001) than at stations where whales were not present (mean total densities were 6.54 × 103 (SE = 1.03 × 103) and 0.87 × 103 (SE = 0.19 × 103) organisms/m3, respectively). Feeding was rarely observed in locations where the total zooplankton density was less than 1000 organisms/m3. The rate of change of direction in the feeding path (mean 19.3°/10 m of path) was significantly higher (P < 0.001) than for paths of whales travelling (mean 5.3°/10 m of path), reflecting area-restricted foraging behaviour.

scholarly journals How we can all stop killing whales: a proposal to avoid whale entanglement in fishing gear

2019 ◽  
Vol 76 (4) ◽  
pp. 781-786 ◽  
Author(s):  
Michael J Moore
Keyword(s):  
Endangered Species ◽  
Water Column ◽  
North Atlantic ◽  
Cape Cod ◽  
Fishing Gear ◽  
Eastern Canada ◽  
North Atlantic Right Whale ◽  
Right Whale ◽  
The North ◽  
The North Atlantic

Abstract Whales are federally protected by the Marine Mammal Protection Act; endangered species, such as the North Atlantic right whale, receive additional protection under the Endangered Species Act. However, their regulations have failed to satisfy conservation and animal welfare concerns. From 1990 to 2011 the North Atlantic right whale (Eubalaena glacialis, NARW) population grew at a mean of 2.8% annually. However, population trends reversed since 2011; the species is in decline, with only ∼100 reproductively active females remaining. This failure is driven by vessel collisions and increasingly fatal and serious entanglement in fixed fishing gear, whose rope strength has increased substantially. Chronic entanglement, drag, and associated morbidity have been linked to poor fecundity. Genuine solutions involve designating areas to be avoided and speed restrictions for ships and removing fishing trap ropes from the water column. A trap fishing closure for NARW habitat in the Cape Cod Bay (U.S.) area has been in place seasonally since 2015. 2017 mortalities in Eastern Canada elicited substantive management changes whereby the 2018 presence of NARW in active trap fishing areas resulted in an effective closure. To avoid these costly closures, the traditional trap fishery model of rope end lines attached to surface marker buoys has to be modified so that traps are marked virtually, and retrieved with gear that does not remain in the water column except during trap retrieval. Consumer demand for genuinely whale-safe products will augment and encourage the necessary regulatory changes so that trap fisheries conserve target and nontarget species.

scholarly journals What Hope for North Atlantic Right Whales?

Oryx ◽  
1982 ◽  
Vol 16 (3) ◽  
pp. 255-262
Author(s):  
Randall Reeves
Keyword(s):  
North Atlantic ◽  
Oil Refinery ◽  
North Atlantic Right Whale ◽  
International Convention ◽  
Atlantic Population ◽  
Right Whale ◽  
The North ◽  
Right Whales ◽  
North Atlantic Right Whales ◽  
The North Atlantic

In the early 1800s the once abundant North Atlantic right whale was believed to be extinct. But by mid-century the species had been ‘rediscovered’, and hunting was resumed until 1918, when the whales were again in trouble. In 1935 all right whales became fully protected by an international convention, and in the 1950s the North Atlantic population was once again ‘rediscovered’. Today, after nearly 50 years of protection and slow recovery, the author assesses the present status of the North Atlantic population. Surveys showed disappointing results until in 1980 a survey of the lower Bay of Fundy (prompted by the threat of an oil refinery being built there) revealed surprisingly high numbers. Another survey in 1981, in which the author also took part, has shown the Grand Manan Island region to be a summer and autumn assembly site for at least several dozen of these endangered whales, including a number of cows and calves. This may be a key area for the North Atlantic right whale's survival.

Comparison of genetic variability of North and South Atlantic right whales (Eubalaena), using DNA fingerprinting

1997 ◽  
Vol 75 (7) ◽  
pp. 1073-1080 ◽  
Author(s):  
Catherine M. Schaeff ◽  
Scott D. Kraus ◽  
Moira W. Brown ◽  
Judy S. Perkins ◽  
Roger Payne ◽  
...  
Keyword(s):  
Genetic Variability ◽  
North Atlantic ◽  
Population Data ◽  
South Atlantic ◽  
North Atlantic Right Whale ◽  
Right Whale ◽  
The North ◽  
Sharing Values ◽  
Right Whales ◽  
North Atlantic Right Whales

The North Atlantic right whale (Eubalaena glacialis) is the most endangered large whale in the world and shows few signs of recovery despite over 60 years of protection. In contrast, the South Atlantic right whale (E. australis), a closely related species, appears to be recovering successfully. Using DNA extracted from skin biopsy samples and two hypervariable minisatellite probes, we compared the levels of genetic diversity within the two populations. Our results revealed that unrelated North Atlantic (NA) right whales exhibit significantly less genetic variation than unrelated South Atlantic (SA) right whales (Jeffreys 33.15 (J33.15) probe: SNA-U-observed = 0.56 versus SSA-U-observed = 0.37, p < 0.01; M13 probe: SNA-U-observed = 0.74 versus SSA-U-observed = 0.46, p < 0.01). The level of band sharing among unrelated North Atlantic right whales was greater than that predicted for second-degree-related South Atlantic right whales (J33.15: SNA-U-observed = 56 versus SSA-2°-expected = 0.53, p < 0.05; M13: SNA-U-observed = 0.74 versus SSA-2°-expected = 0.60, p < 0.01), indicating that the northern animals have lost a substantial amount of genetic variability. Observed band sharing among North Atlantic first-degree relatives was lower than expected, based on band sharing among unrelated animals (J33.15: SNA-1°-observed = 0.67 versus SNA-1°-expected = 0.78, p < 0.01; M13: SNA-1°-observed = 0.83 versus SNA-1°-expected = 0.87, p = 0.15). This suggests that the matings between closely related individuals that would have resulted in the higher band-sharing values were unsuccessful. These results, in conjunction with behavioral and population data which indicate that North Atlantic right whales may be suffering from reduced fertility, fecundity, and juvenile survivorship, support the hypothesis that inbreeding depression is influencing the recovery of this species.

Genetic analysis of 16th-century whale bones prompts a revision of the impact of Basque whaling on right and bowhead whales in the western North Atlantic

2004 ◽  
Vol 82 (10) ◽  
pp. 1647-1654 ◽  
Author(s):  
Toolika Rastogi ◽  
Moira W Brown ◽  
Brenna A McLeod ◽  
Timothy R Frasier ◽  
Robert Grenier ◽  
...  
Keyword(s):  
Genetic Analysis ◽  
North Atlantic ◽  
North Atlantic Right Whale ◽  
Bowhead Whales ◽  
Right Whale ◽  
The North ◽  
Dramatic Decline ◽  
Right Whales ◽  
The North Atlantic ◽  
The Impact

The North Atlantic right whale, Eubalaena glacialis (Müller, 1776), is one of the world's most endangered large cetaceans. It is widely believed that Basque whalers caused the most dramatic decline of this species in the western North Atlantic during the early-16th and 17th centuries. Previous osteological analysis of 17 historic bones suggested that 50% of the Basque harvest consisted of right whales and 50% of bowhead whales, Balaena mysticetus L., 1758. This 50:50 ratio has been used to estimate pre-exploitation population size, which has subsequently formed the basis of recovery goals and plans for the North Atlantic right whale. Genetic analysis of 21 bones, 13 identified as right whales and 8 as bowhead whales through osteological examination, indicates that in fact only 1 bone was a right whale and 20 were bowhead whales. Additionally, preliminary microsatellite analyses of this specimen are not consistent with the hypothesis that whaling resulted in the low genetic variation found in this species today. These results differ from what would be expected based on any previous view of Basque whaling, and raise questions regarding the impact of Basque whaling on this species.

scholarly journals Ocean Regime Shift is Driving Collapse of the North Atlantic Right Whale Population

Oceanography ◽  
2021 ◽  
Vol 34 (3) ◽  
pp. 22-31
Author(s):  
Erin Meyer-Gutbrod ◽  
◽  
Charles Greene ◽  
Kimberley Davies ◽  
David Johns
Keyword(s):  
North Atlantic ◽  
Regime Shift ◽  
Gulf Of Maine ◽  
Scotian Shelf ◽  
North Atlantic Right Whale ◽  
Right Whale ◽  
The North ◽  
Right Whales ◽  
The North Atlantic ◽  
Foraging Environment

Ocean warming linked to anthropogenic climate change is impacting the ecology of marine species around the world. In 2010, the Gulf of Maine and Scotian Shelf regions of the Northwest Atlantic underwent an unprecedented regime shift. Forced by climate-driven changes in the Gulf Stream, warm slope waters entered the region and created a less favorable foraging environment for the endangered North Atlantic right whale population. By mid-decade, right whales had shifted their late spring/summer foraging grounds from the Gulf of Maine and the western Scotian Shelf to the Gulf of St. Lawrence. The population also began exhibiting unusually high mortality in 2017. Here, we report that climate-driven changes in ocean circulation have altered the foraging environment and habitat use of right whales, reducing the population’s calving rate and exposing it to greater mortality risks from ship strikes and fishing gear entanglement. The case of the North Atlantic right whale provides a cautionary tale for the management of protected species in a changing ocean.

scholarly journals The Painful Side of Trap and Fixed Net Fisheries: Chronic Entanglement of Large Whales

2012 ◽  
Vol 2012 ◽  
pp. 1-4 ◽  
Author(s):  
Michael J. Moore ◽  
Julie M. van der Hoop
Keyword(s):  
Marine Mammals ◽  
Well Being ◽  
Eubalaena Glacialis ◽  
North Atlantic Right Whale ◽  
Right Whale ◽  
The North ◽  
Management Measures ◽  
Population Sustainability ◽  
The Individual ◽  
Severe Tissue

Concern over the well-being of marine mammals at sea has focused on intentional harvests, both in terms of individual welfare and population sustainability. Unintentional mortalities from fishing gear entanglement are primarily seen as a risk to population viability. Additionally, larger whales breaking free of, and subsequently carrying, fixed trap and net gear are subject to a very slow demise, averaging 6 months in the case of the North Atlantic right whale (Eubalaena glacialis). Chronic cases can involve impaired foraging, increased drag, infection, hemorrhage, and severe tissue damage. The individual suffering of these cases appears to be extreme. Thus management measures should go beyond legally mandated conservation measures to include avoidance of such scenarios. Seafood consumers could succeed, where laws have failed, to demand fishing practices that do not kill whales in this manner. The effective absence of such demands would seem to reflect the cryptic nature of these cases to most consumers.

Analysis of fecal glucocorticoids in the North Atlantic right whale (Eubalaena glacialis)

2006 ◽  
Vol 148 (2) ◽  
pp. 260-272 ◽  
Author(s):  
Kathleen E. Hunt ◽  
Rosalind M. Rolland ◽  
Scott D. Kraus ◽  
Samuel K. Wasser
Keyword(s):  
North Atlantic ◽  
Eubalaena Glacialis ◽  
North Atlantic Right Whale ◽  
Right Whale ◽  
The North ◽  
The North Atlantic ◽  
Fecal Glucocorticoids

Fishing-gear threat to right whales (Eubalaena glacialis) in Canadian waters and the risk of lethal entanglement

2011 ◽  
Vol 68 (12) ◽  
pp. 2174-2193 ◽  
Author(s):  
Angelia S.M. Vanderlaan ◽  
R. Kent Smedbol ◽  
Christopher T. Taggart
Keyword(s):  
Relative Risk ◽  
North Atlantic ◽  
Eubalaena Glacialis ◽  
Bay Of Fundy ◽  
Commercial Fishing ◽  
Fishing Gear ◽  
Critical Habitat ◽  
North Atlantic Right Whale ◽  
Right Whale ◽  
Right Whales

Commercial fishing gear can potentially entangle any whale, and this is especially true for the endangered North Atlantic right whale ( Eubalaena glacialis ), for which entanglement is second only to vessel strike as being responsible for documented right whale deaths. We use right whale survey data and Canadian fishing-gear deployment data to estimate the relative threat of gear entanglement in a Scotia–Fundy study area and the relative risk of lethal entanglement in the Bay of Fundy and on Roseway Basin, Scotian Shelf, where Critical Habitat has been legislated. We focus on groundfish and pelagic hook-and-line; groundfish gillnet; and crab-, hagfish-, and inshore and offshore lobster-trap gear. Our analyses demonstrate that groundfish hook-and-line gear poses the greatest threat to right whales among the seven gear types analysed during the summer-resident period in Critical Habitat and that gear from the lobster fisheries poses the greatest threat during the spring and autumn periods when whales are migrating to and from Critical Habitat. We suggest that area-specific seasonal closures of some fisheries would reduce threat and risk to whales without unduly compromising fishing interests.

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