scholarly journals Abundance of whales in West and East Greenland in summer 2015

2019 ◽  
Vol 11 ◽  
Author(s):  
Rikke Guldborg Hansen ◽  
Tenna K. Boye ◽  
Rasmus S. Larsen ◽  
Nynne H. Nielsen ◽  
Outi Tervo ◽  
...  
Keyword(s):  
Shelf Break ◽  
Estimation Methods ◽  
Baleen Whale ◽  
Pilot Whale ◽  
East Greenland ◽  
West Greenland ◽  
Minke Whales ◽  
Abundance Estimates ◽  
Recent Climate ◽  
Pilot Whales

An aerial line transect survey of whales in West and East Greenland was conducted in August-September 2015. The survey covered the area between the coast of West Greenland and offshore (up to 100 km) to the shelf break. In East Greenland, the survey lines covered the area from the coast up to 50 km offshore crossing the shelf break. A total of 423 sightings of 12 cetacean species were obtained and abundance estimates were developed for common minke whale, (Balaenoptera acutorostrata) (32 sightings), fin whale (Balaenoptera physalus) (129 sightings), humpback whale (Megaptera novaeangliae) (84 sightings), harbour porpoise (Phocoena phocoena) (55 sightings), long-finned pilot whale, (Globicephala melas) (42 sightings) and white-beaked dolphin (Lagenorhynchus albirostri) (50 sightings). The developed at-surface abundance estimates were corrected for both perception bias and availability bias if possible. Data on surface corrections for minke whales and harbour porpoises were collected from whales instrumented with satellite-linked time-depth-recorders. Options for estimation methods are presented and the preferred estimates are: minke whales: 5,095 (95% CI: 2,171-11,961) in West Greenland and 2,762 (95% CI: 1,160-6,574) in East Greenland, fin whales: 2,215 (95% CI: 1,017-4,823) in West Greenland and 6,440 (95% CI: 3,901-10,632) in East Greenland, humpback whales: 993 (95% CI: 434-2,272) in West Greenland and 4,223 (95% CI: 1,845-9,666) in East Greenland, harbour porpoises: 83,321 (95% CI: 43,377-160,047) in West Greenland and 1,642 (95% CI: 319-8,464) in East Greenland, pilot whales: 9,190 (95% CI: 3,635-23,234) in West Greenland and 258 (95% CI: 50-1,354) in East Greenland, white-beaked dolphins 15,261 (95% CI: 7,048-33,046) in West Greenland and 11,889 (95% CI: 4,710-30,008) in East Greenland. The abundance of cetaceans in coastal areas of East Greenland has not been estimated before, but the limited historical information from the area indicates that the achieved abundance estimates were remarkably high. When comparing the abundance estimates from 2015 in West Greenland with a similar survey conducted in 2007, there is a clear trend towards lower densities in 2015 for the three baleen whale species and white-beaked dolphins. Harbour porpoises and pilot whales, however, did not show a similar decline. The decline in baleen whale and white-beaked dolphin abundance is likely due to emigration to the East Greenland shelf areas where recent climate driven changes in pelagic productivity may have accelerated favourable conditions for these species.

scholarly journals Abundance of Whales in West and East Greenland in Summer 2015

2018 ◽  
Author(s):  
Rikke G. Hansen ◽  
Tenna K. Boye ◽  
Rasmus S. Larsen ◽  
Nynne H. Nielsen ◽  
Outi Tervo ◽  
...  
Keyword(s):  
Shelf Break ◽  
Minke Whale ◽  
Harbour Porpoise ◽  
Baleen Whale ◽  
Pilot Whale ◽  
East Greenland ◽  
West Greenland ◽  
Minke Whales ◽  
Abundance Estimates ◽  
Pilot Whales

ABSTRACTAn aerial line transect survey of whales in West and East Greenland was conducted in August-September 2015. The survey covered the area between the coast of West Greenland and offshore (up to 100 km) to the shelf break. In East Greenland, the survey lines covered the area from the coast up to 50 km offshore crossing the shelf break. A total of 423 sightings of 12 cetacean species were obtained and abundance estimates were developed for common minke whale, from now on called minke whale, (Balaenoptera acutorostrata)(32 sightings), fin whale (Balaenoptera physalus) (129 sightings), humpback whale (Megaptera novaeangliae)(84 sightings), harbour porpoise (Phocoena phocoena)(55 sightings), long-finned pilot whale, from now on called pilot whale, (Globicephala melas)(42 sightings) and white-beaked dolphins (Lagenorhynchus albirostri)(50 sightings). The developed at-surface abundance estimates were corrected for both perception bias and availability bias if possible. Data on surface corrections for minke whales and harbour porpoises were collected from whales instrumented with satellite-linked time-depth-recorders. Options for estimation methods are presented and the preferred estimates are: Minke whales: 5,095 (95% CI: 2,171-11,961) in West Greenland and 2,762 (95% CI: 1,160-6,574) in East Greenland, fin whales: 2,215 (95% CI: 1,017-4,823) in West Greenland and 6,440 (95% CI: 3,901-10,632) in East Greenland, humpback whales: 993 (95% CI: 434-2,272) in West Greenland and 4,223 (95%CI: 1,845-9,666) in East Greenland, harbour porpoise: 83,321 (95% CI: 43,377-160,047) in West Greenland and 1,642 (95% CI: 319-8,464) in East Greenland, pilot whales: 9,190 (95% CI: 3,635-23,234) in West Greenland and 258 (95% CI: 50-1,354) in East Greenland, white-beaked dolphins 15,261 (95% CI: 7,048-33,046) in West Greenland and 11,889 (95% CI: 4,710-30,008) in East Greenland. The abundance of cetaceans in coastal areas of East Greenland has not been estimated before, but the limited historical information from the area indicate that the achieved abundance estimates were remarkably high. When comparing the abundance estimates from 2015 in West Greenland with a similar survey conducted in 2007 there is a clear trend towards lower densities in 2015 for the three baleen whale species and white-beaked dolphins. Harbour porpoises and pilot whales however, did not show a similar decline. The decline in baleen whale and white-beaked dolphin abundance is likely due to emigration to the East Greenland shelf areas where recent climate driven changes in pelagic productivity may have accelerated favourable conditions for these species.

scholarly journals An assessment of Greenland walrus populations

2005 ◽  
Vol 62 (2) ◽  
pp. 266-284 ◽  
Author(s):  
Lars Witting ◽  
Erik W. Born
Keyword(s):  
Protective Measures ◽  
East Greenland ◽  
Baffin Bay ◽  
West Greenland ◽  
Population Dynamic Model ◽  
The North ◽  
Structured Population ◽  
Abundance Estimates ◽  
North Water ◽  
A Current

AbstractRecent abundance estimates were combined with historical catches and an age- and sex-structured population dynamic model to perform Bayesian assessments of the walrus (Odobenus rosmarus) populations in West Greenland, the North Water in northern Baffin Bay, and East Greenland. The model assumed density-regulated dynamics and pre-harvest populations in population-dynamical equilibrium. It projected the populations under the influence of the catches to estimate the historical trajectories and the current population status. It was found that the West Greenland and North Water populations have been heavily exploited during the last century with the current abundance being at best only a few per cent of the historical abundance. Apparently these populations are still being exploited above sustainable level. The East Greenland population was heavily exploited after 1889 and during the first half of the 20th century and was depleted to approximately 50% of pristine population size in 1933. After protective measures were introduced in the 1950s this population has increased to a current level close to the abundance in 1889, and the present exploitation appears to be sustainable.

scholarly journals Population dynamics of walruses in Greenland

2014 ◽  
Vol 9 ◽  
pp. 191 ◽  
Author(s):  
Lars Witting ◽  
Erik Born
Keyword(s):  
Baffin Island ◽  
Continuous Increase ◽  
East Greenland ◽  
Baffin Bay ◽  
West Greenland ◽  
Structure Information ◽  
Abundance Estimate ◽  
Structured Population Models ◽  
Abundance Estimates ◽  
The 1960S

The historical and current dynamics of the three Atlantic walrus (Odobenus rosmarus rosmarus) populations that occur in Greenland are estimated using age- and sex-structured population models with exponential growth, density-regulated growth and selection-delayed dynamics. These models are integrated with data in a Bayesian framework, where the likelihood of the simulated population trajectories are evaluated from recent abundance estimates and age-structure information from a selective hunt. The overall decline in the Baffin Bay population caused by historical catches is unclear due to incomplete catch reporting prior to 1950s. However, it is estimated that the population declined by 40% from the 1960s to 2005; decreased catches (≈ 140 to ≈ 70) have subsequently allowed this population to increase. The 2012 abundance estimate is 1,400 (95% CI: 1,000-2,000) individuals, and the annual natural growth rate in this population is now 7.7% (95% CI: 6.7-8.9%). Averaging across models, it is estimated that West Greenland/Baffin Island walruses declined by 80% from 7,000 (95% CI: 5,400-10,000) in 1900 to 1,350 (CI: 950-1,950) in 1960. Hereafter they increased to 3,100 (95% CI: 2,500-4,400) in 1993, and owing to increased catches they have experienced a minor decline between 1994 and the early 2000s. Annual catches where then cut from 190 to the current quota of 61, and the population is again increasing with a 2012 estimate of 3,900 (95% CI: 2,500-5,300) individuals. A 2012 estimate of 1,400 (95% CI: 700-3,100) walruses in East Greenland is recovered relative to 1888; the year prior to our first historical catches by European sealers. The historical trajectory, however, is uncertain: Density regulation estimates a relatively flat trajectory, with a maximal depletion in 1890 to 80% of the initial abundance, and a slow continuous increase to almost no current growth. A recovered population is also estimated by selection-delayed dynamics. However, this model estimates a continued increase, and a historical depletion to 2% in 1957. These results are only partially comparable with an earlier assessment for East Greenland. Updated abundance estimates for West Greenland, and modelling with age-structured data from Baffin Bay, have greatly improved our status estimates for Baffin Bay and West Greenland/Baffin Island.

Mantle xenoliths from Tertiary lavas and dykes on Ubekendt Ejland, West Greenland

1998 ◽  
pp. 152-154
Author(s):  
Stefan Bernstein ◽  
C. Kent Brooks
Keyword(s):  
Field Work ◽  
Mantle Xenoliths ◽  
Alkaline Basalt ◽  
Basalt Flow ◽  
Volcanic Province ◽  
East Greenland ◽  
Original Series ◽  
West Greenland ◽  
Ultramafic Xenoliths ◽  
Extensive Collection

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Bernstein, S., & Brooks, C. K. (1998). Mantle xenoliths from Tertiary lavas and dykes on Ubekendt Ejland, West Greenland. Geology of Greenland Survey Bulletin, 180, 152-154. https://doi.org/10.34194/ggub.v180.5099 _______________ Mantle xenoliths were found in Tertiary alkaline (basanitic) lavas on Ubekendt Ejland in West Greenland in the mid 1970s by J.G. Larsen. Microprobe analyses of olivine, pyroxene and spinel in two mantle xenoliths, suggested that the xenoliths on Ubekendt Ejland are highly depleted and have high modal olivine contents, and low modal orthopyroxene and clinopyroxene (Larsen 1982). In this respect the mantle xenoliths from Ubekendt Ejland are very similar to the spinel harzburgites from Wiedemann Fjord, in the Tertiary volcanic province of East Greenland (Brooks & Rucklidge 1973; Bernstein et al. 1998). Larsen (1981) also reported dykes containing mantle nodules and a varied suite of cumulates and megacrysts, one of which has subsequently been dated to 34.1 ± 0.2 Ma (Storey et al. 1998) The basalt flow that carries the xenoliths is from what is defined as the Erqua Formation which occurs at the top of the lava succession in western Ubekendt Ejland (Fig. 1; Drever & Game 1948; Larsen 1977a, b). The basalts have not been dated, but are younger than 52.5 Ma, which is the date obtained for the underlying formation (Storey et al. 1998). During July 1997, we spent three weeks collecting xenoliths and prospecting for xenolith-bearing dykes in the Uummannaq district of central West Greenland. The field work resulted in an extensive collection of xenoliths from an alkaline basalt flow described by Larsen (1977a, b), as well as the discovery of a dyke carrying a large number of ultramafic xenoliths of various origins. 

The year in focus, 2000

2001 ◽  
pp. 7-10
Author(s):  
Kai Sørensen
Keyword(s):  
Geological Mapping ◽  
Geological Survey ◽  
Seismic Survey ◽  
East Greenland ◽  
Major Field ◽  
Original Series ◽  
West Greenland ◽  
Level Of Activity ◽  
Field Activity ◽  
Year 2000

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Sørensen, K. (2001). The year in focus, 2000. Geology of Greenland Survey Bulletin, 189, 7-10. https://doi.org/10.34194/ggub.v189.5148 _______________ The year 2000 was unusual in that it lacked major field activity directly involved with the systematic geological mapping of Greenland. However, field activities were again many and varied, including a successful highresolution seismic survey offshore central West Greenland, and a joint Geological Survey of Denmark and Greenland (GEUS) – Danish Lithosphere Centre (DLC) project centred on Kangerlussuaq in southern East Greenland. Of the Survey’s 354 personnel, 93 were allocated to Greenland-related activities (Table 1). The Greenland level of activity in 2000, both in Copenhagen and in the field, thus compared favourably with that of 1999.

scholarly journals Love-iathan, the meat-whale and hidden people: ordering Faroese pilot whaling

2016 ◽  
Vol 23 (1) ◽  
pp. 26 ◽  
Author(s):  
Benedict E. Singleton
Keyword(s):  
News Item ◽  
Faroe Islands ◽  
Political Ontology ◽  
Pilot Whale ◽  
Environmental Dispute ◽  
Pilot Whales ◽  
Ocean Environment

A key question in any environmental dispute is the nature of what is under discussion. 'Cosmopolitics' – political battles over the form of reality – are a feature of many environmental clashes. This article focuses on one such clash: during the summer of 2014, grindadráp – the iconic practice of driving pilot whales for meat – was the big news item in the Faroe Islands. More accurately, a conservation campaign by the controversial group Sea Shepherd Conservation Society (SSCS), Operation Grindstop 2014, garnered most attention. Aiming to stop or at least disrupt the 'barbaric' and 'sadistic' grindadráp, SSCS were involved in several confrontations with Faroese authorities and publicly engaged with Faroese pro-whaling advocates in several discussions that were seemingly fruitless. Based on 3 months fieldwork during the campaign, this article describes a 'political ontology' of Grindstop 2014. What emerged was a 'hybrid' born of a clash between two fundamentally dissonant systems of ordering, which structured and were reinforced by various practices, both discursive and material. Activists on both sides were engaged in a cosmopolitical struggle to decisively enact their orderings, creating alternative stories of whales, Faroese whaling, the ocean environment and modernity. The aim is to understand what happened when these orderings met. This article argues that throughout the summer these two orderings moved apart, consequently hiding the diversity of opinion and discussion within Faroese society around grindadráp. As such, alternative orderings of grindadráp were suppressed, notably those voiced by Faroese activists arguing that the practice should cease because of the high levels of toxins in pilot whale meat.Key words: Faroe Islands, whaling, political ontology, cosmopolitics

scholarly journals Holocene shore-lines and glacial stages in Greenland - an attempt at correlation

1972 ◽  
Vol 41 ◽  
pp. 1-39
Author(s):  
A Weidick
Keyword(s):  
North America ◽  
Current Literature ◽  
Younger Dryas ◽  
Low Pressure ◽  
East Greenland ◽  
West Greenland ◽  
History Of ◽  
Climatic Optimum ◽  
North Greenland

Post-Wisconsinian uplift of West, North and East Greenland has been estimated on the basis of information in current literature and compared to the data collected by the author in central West Greenland. For West and North Greenland the dated uplift allows an estimate to be made of the age of former shore-lines, which in turn have been used to date the stages of the extent of the Inland lce. The results have been compared with published information on the age of glacial stages in East Greenland. The estimated ages of the ice margin stages imply a history of deglaciation in West (and North?) Greenland comparable to that of North America. In both areas the major deglaciation took place after the Younger Dryas and a marked halt took place in Boreal times. It is possibie that the history of East Greenland is more closely related to that of Scandinavia where a widespread deglaciation took place prior to the Younger Dryas. The deglaciation of North Greenland was interrupted by a marked readvance or readvances during the climatic optimum. It is possible that the northward shift of the low pressure centres during this period led to an increased accumulation on the northern part of the Inland lce.

scholarly journals Whales as Indicators of Historical and Current Changes in the Marine Ecosystem of the Indo-Pacific Sector of the Antarctic

2020 ◽  
Author(s):  
Yoshihiro Fujise ◽  
Luis A. Pastene
Keyword(s):  
Marine Ecosystem ◽  
Recruitment Rate ◽  
Minke Whale ◽  
Past Century ◽  
Baleen Whale ◽  
The Past ◽  
Antarctic Minke Whale ◽  
Minke Whales ◽  
Nutritional Conditions ◽  
The Antarctic

We review the scientific information on whales that could be indicative of historical and current changes in the ecosystem in the Indo-Pacific sector of the Antarctic. The increased krill availability in the middle of the past century as a result of the heavy harvesting of the larger baleen whale species could have been translated into better nutritional conditions for the Antarctic minke whale, resulting in a decreasing trend in the age at sexual maturity and an increasing trend in recruitment rate and hence total population size between approximately 1940 and 1970. This nutritional condition has deteriorated more recently, as revealed by a decrease in energy storage and stomach content weight since the 1980’s; these changes coincide with appreciable increases in the abundances of humpback and fin whales, which were heavily harvested in the first half of the past century. The historical demographic changes observed in the Antarctic minke whale are consistent with the pattern to be expected under the krill surplus hypothesis, with minke whales now again competing with other (recovering) baleen whale species for krill. However, these minke whales could also be using alternative feeding areas (e.g. polynias within the pack-ice) in response to the increase in abundance and geographical expansion of these other large whale species. This could provide an alternative explanation for indications from sighting surveys and population models of a decrease and then re-stabilisation of minke whale abundance in open water areas since the 1970s.

scholarly journals Application of seismo-stratigraphic interpretation techniques to offshore West Greenland

1988 ◽  
Vol 140 ◽  
pp. 64-66
Author(s):  
J.A Chalmers
Keyword(s):  
Pilot Study ◽  
Seismic Data ◽  
Seismic Interpretation ◽  
Shelf Break ◽  
The West ◽  
Regional Geology ◽  
West Greenland ◽  
Oil Companies ◽  
Greenland Basin ◽  
Basement Ridge

A pilot study is being conducted to determine if the use of seismo-stratigraphic interpretation techniques can increase the understanding af the geology of offshore West Greenland in order to reassess the prospectivity of the area. During the period 1975 to 1979, a number of concessions offshore West Greenland were licensed to various consortia of oil companies to search for petroleum. Some 40 000 km of seismic data were acquired, all of which is now released. Five wells were drilled, all of them dry, and all concessions were relinquished by the industry by 1979. The regional geology of offshore West Greenland has been summarised by Manderscheid (1980) and Henderson et al. (1981). They show the West Greenland Basin to consist of fairly uniformly westward dipping sediments bordered near the shelf break by a basement ridge. These authors used what may be termed 'conventional' techniques of seismic interpretation. However, since that time the techniques of seismo-stratigraphy (Vail et al., 1977; Hubbard et al., 1985) have become established. They are now being applied to study seismic data acquired during the mid-1970s.

Electrophoretic differentiation among local populations of the long-finned pilot whale, Globicephala melaena, at the Faroe Islands

1988 ◽  
Vol 66 (8) ◽  
pp. 1884-1892 ◽  
Author(s):  
Liselotte Wesley Andersen
Keyword(s):  
Reproductive Isolation ◽  
Muscle Tissue ◽  
Gel Electrophoresis ◽  
Faroe Islands ◽  
Starch Gel Electrophoresis ◽  
Pilot Whale ◽  
Local Populations ◽  
Starch Gel ◽  
Pilot Whales ◽  
Polymorphic Enzymes

Enzyme variation within and between nine schools of long-finned pilot whales, Globicephala melaena, caught at the Faroe Islands, was examined by starch gel electrophoresis. Twenty-seven enzymes were investigated, representing 41 loci, of which three were polymorphic. The polymorphic enzymes were analyzed in either liver or muscle tissue from 628 specimens. No heterogeneity within the schools was observed, while significant differences in allele frequencies between schools were detected by a multilocus G-test. This result indicated some degree of reproductive isolation.

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