17 results on '"Helena Herr"'
Search Results
2. Return of large fin whale feeding aggregations to historical whaling grounds in the Southern Ocean
- Author
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Helena Herr, Sacha Viquerat, Fredi Devas, Abigail Lees, Lucy Wells, Bertie Gregory, Ted Giffords, Dan Beecham, and Bettina Meyer
- Subjects
Multidisciplinary ,Fin Whale ,Oceans and Seas ,Whales ,Animals ,Antarctic Regions ,Ecosystem - Abstract
Fin whales (Balaenoptera physalus quoyi) of the Southern Hemisphere were brought to near extinction by twentieth century industrial whaling. For decades, they had all but disappeared from previously highly frequented feeding grounds in Antarctic waters. Our dedicated surveys now confirm their return to ancestral feeding grounds, gathering at the Antarctic Peninsula in large aggregations to feed. We report on the results of an abundance survey and present the first scientific documentation of large fin whale feeding aggregations at Elephant Island, Antarctica, including the first ever video documentation. We interpret high densities, re-establishment of historical behaviours and the return to ancestral feeding grounds as signs for a recovering population. Recovery of a large whale population has the potential to augment primary productivity at their feeding grounds through the effects of nutrient recycling, known as 'the whale pump'. The recovery of fin whales in that area could thus restore ecosystem functions crucial for atmospheric carbon regulation in the world's most important ocean region for the uptake of anthropogenic CO2.
- Published
- 2022
3. Osteo-pathological analysis provides evidence for a survived historical ship strike in a Southern Hemisphere fin whale (Balaenoptera physalus)
- Author
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Hannah Viola Daume, Helena Herr, Heinrich Mallison, Matthias Glaubrecht, and Thomas M. Kaiser
- Subjects
Multidisciplinary - Abstract
The life history of a fin whale (Balaenoptera physalus) caught during whaling operations in the 1950s was partly reconstructed. 3D surface models of the bones of the skeleton curated at the Zoological Museum of Hamburg were used for an osteopathological analysis. The skeleton revealed multiple healed fractures of ribs and a scapula. Moreover, the processus spinosi of several vertebrae were deformed and arthrosis was found. Together, the pathological findings provide evidence for large blunt trauma and secondary effects arising from it. Reconstruction of the likely cause of events suggests collision with a ship inflicting the fractures and leading to post traumatic posture damage as indicated by skeletal deformations. The injured bones had fully healed before the fin whale was killed by a whaler in the South Atlantic in 1952. This study is the first in-detail reconstruction of a historical whale—ship collision in the Southern Hemisphere, dating back to the 1940s, and the first documentation of a healed scapula fracture in a fin whale. The skeleton provides evidence for survival of a ship strike by a fin whale with severe injuries causing long-term impairment.
- Published
- 2023
4. Rückkehr der Finnwale in die Antarktis
- Author
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Helena Herr
- Subjects
Geography ,General Agricultural and Biological Sciences - Published
- 2020
5. Opportunistically collected data from aerial surveys reveal spatio-temporal distribution patterns of marine debris in German waters
- Author
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Anita Gilles, Patricia Burkhardt-Holm, S. Viquerat, Bianca Unger, Helena Herr, and Ursula Siebert
- Subjects
0106 biological sciences ,Monitoring ,Aerial survey ,Health, Toxicology and Mutagenesis ,Marine life ,Marine pollution ,010501 environmental sciences ,01 natural sciences ,Aerial surveys ,Marine Strategy Framework Directive ,Nature conservation ,Surveys and Questionnaires ,biology.animal ,Marine debris ,Environmental Chemistry ,0105 earth and related environmental sciences ,computer.programming_language ,Waste Products ,biology ,Offshore and coastal waters ,010604 marine biology & hydrobiology ,General Medicine ,Pollution ,Debris ,Harbour ,Environmental science ,Submarine pipeline ,North Sea ,Physical geography ,Plastics ,computer ,Porpoise ,Environmental Monitoring ,Research Article - Abstract
Marine debris is known for its ubiquitousness and harmful effects on marine life. This study is the first analysis to provide information on the distribution of floating marine debris in German waters using aerial survey data collected between 2002 and 2016. During regular harbour porpoise monitoring flights, 191,167 km were covered and 26,512 floating debris items recorded (average encounter rate 0.1387 items/km). Debris was encountered more often in the North Sea than in the Baltic Sea (0.16 items/km; 0.08 items/km). The average encounter rate was higher in offshore waters than in coastal areas. Overlaps of marine debris distribution with ‘Special Areas of Conservation’ are a particular reason for concern. Moreover, the spring months (March–May) were identified to be the time of the year with the highest average encounter rates for marine debris. Fishing-related debris was shown to contribute up to 25% of the total number of all observed items. This study shows that opportunistically collected data on marine debris from aerial surveys are valuable for identifying distribution patterns of floating debris without additional survey effort and costs. These data can be used as baseline information to inform management schemes such as the Marine Strategy Framework Directive.
- Published
- 2020
6. Injuries, Malformations, and Epidermal Conditions in Cetaceans of the Strait of Gibraltar
- Author
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Ursula Siebert, Jorn Selling, Katharina Heyer, Patricia Burkhardt-Holm, and Helena Herr
- Subjects
Balaenoptera ,biology ,Common dolphin ,Whale ,Delphinus delphis ,Aquatic Science ,biology.organism_classification ,Bottlenose dolphin ,Pilot whale ,Fishery ,Geography ,Sperm whale ,biology.animal ,Animal Science and Zoology ,Minke whale ,Nature and Landscape Conservation - Abstract
The Strait of Gibraltar is a heavily used marine area, with intense fishing operations and one of the busiest shipping lanes worldwide. Concurrently, the Strait of Gibraltar is home to eight regularly occurring species of cetaceans. Thus, the potential for conflict between man and cetaceans is high. Injuries and external anomalies may serve as indicators for anthropogenic impacts and exposure to human activities. To explore potential impacts to cetacean populations inhabiting the Strait of Gibraltar, we analysed photographs taken opportunistically during whale-watching operations from 2001 to 2015. Externally visible conspicuous features and anomalies were detected in all of the eight regularly occurring cetacean species: long beaked common dolphin (Delphinus delphis), striped dolphin (Stenella coeruleoalba), common bottlenose dolphin (Tursiops truncatus), long-finned pilot whale (Globicephala melas), killer whale (Orcinus orca), sperm whale (Physeter macrocephalus), fin whale (Balaenoptera physalus), and minke whale (Balaenoptera acutorostrata). Altogether, 502 anomalies were documented in 494 cases of affected cetaceans, including injuries, skin anomalies, emaciation, and neoplasia. Highest prevalence was noted for injuries (245 incidences) of which a minimum of 44 (17%) were consistent with anthropogenic injuries. Our results suggest that human activities in the Strait of Gibraltar, especially fishing activities, pose a threat, particularly to small and medium-sized cetaceans. We, therefore, recommend stricter management enforcement of existing guidelines and laws, as well as the implementation of an area-wide management plan.
- Published
- 2020
7. Aerial surveys for Antarctic minke whales ( Balaenoptera bonaerensis ) reveal sea ice dependent distribution patterns
- Author
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S. Viquerat, Boris Dorschel, Ursula Siebert, Natalie Kelly, M. Scheidat, Linn Sophia Lehnert, Rob Williams, Karl-Hermann Kock, Helena Herr, and Marcus Huntemann
- Subjects
0106 biological sciences ,Aerial survey ,Antarctic minke whale distribution ,010603 evolutionary biology ,01 natural sciences ,03 medical and health sciences ,Abundance (ecology) ,lcsh:QH540-549.5 ,Sea ice ,Bathymetry ,14. Life underwater ,marginal ice zone ,distance sampling ,Southern Ocean ,ship‐based helicopter surveys ,density surface models ,Sea ice concentration ,Ecology, Evolution, Behavior and Systematics ,southern ocean ,030304 developmental biology ,Nature and Landscape Conservation ,0303 health sciences ,geography ,Distance sampling ,geography.geographical_feature_category ,Ecology ,Business Manager projecten Midden-Noord ,ship-based helicopter surveys ,Generalized additive model ,Oceanography ,Balaenoptera bonaerensis ,Environmental science ,lcsh:Ecology ,Business Manager projects Mid-North - Abstract
This study investigates the distribution of Antarctic minke whales (AMW) in relation to sea ice concentration and variations therein. Information on AMW densities in the sea ice‐covered parts of the Southern Ocean is required to contextualize abundance estimates obtained from circumpolar shipboard surveys in open waters, suggesting a 30% decline in AMW abundance. Conventional line‐transect shipboard surveys for density estimation are impossible in ice‐covered regions, therefore we used icebreaker‐supported helicopter surveys to obtain information on AMW densities along gradients of 0%–100% of ice concentration. We conducted five helicopter surveys in the Southern Ocean, between 2006 and 2013. Distance sampling data, satellite‐derived sea‐ice data, and bathymetric parameters were used in generalized additive models (GAMs) to produce predictions on how the density of AMWs varied over space and time, and with environmental covariates. Ice concentration, distance to the ice edge and distance from the shelf break were found to describe the distribution of AMWs. Highest densities were predicted at the ice edge and through to medium ice concentrations. Medium densities were found up to 500 km into the ice edge in all concentrations of ice. Very low numbers of AMWs were found in the ice‐free waters of the West Antarctic Peninsula (WAP). A consistent relationship between AMW distribution and sea ice concentration weakens the support for the hypothesis that varying numbers of AMWs in ice‐covered waters were responsible for observed changes in estimated abundance. The potential decline in AMW abundance stresses the need for conservation measures and further studies into the AMW population status. Very low numbers of AMWs recorded in the ice‐free waters along the WAP support the hypothesis that this species is strongly dependent on sea ice and that forecasted sea ice changes have the potential of heavily impacting AMWs.
- Published
- 2019
8. Marine debris in harbour porpoises and seals from German waters
- Author
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M. Böhmert, Harald Benke, Bianca Unger, Michael Dähne, K. Wolff-Schmidt, Miriam Hillmann, Ursula Siebert, Peter Wohlsein, Patricia Burkhardt-Holm, and Helena Herr
- Subjects
0106 biological sciences ,Oceans and Seas ,Perforation (oil well) ,Fishing ,Phocoena ,Phoca ,Porpoises ,010501 environmental sciences ,Aquatic Science ,Solid Waste ,Oceanography ,01 natural sciences ,Animal Diseases ,Marine mammal ,Marine debris ,Animals ,0105 earth and related environmental sciences ,computer.programming_language ,biology ,010604 marine biology & hydrobiology ,General Medicine ,biology.organism_classification ,Pollution ,Debris ,Fishery ,Geography ,Harbour ,Autopsy ,computer - Abstract
Records of marine debris in and attached to stranded harbour porpoises ( Phocoena phocoena ), harbour seals ( Phoca vitulina ) and grey seals ( Halichoerus grypus ) were studied comprising information on 6587 carcasses collected along the German coast between 1990 and 2014, the decomposition state allowed for necropsy in 1622 cases. Marine debris items were recorded in 31 carcasses including 14 entanglements (5 harbour porpoises, 6 harbour seals, 3 grey seals) and 17 cases of ingestion (4 harbour porpoises, 10 harbour seals, 3 grey seals). Objects comprised general debris (35.1%) and fishing related debris (64.9%). Injuries associated with marine debris included lesions, suppurative ulcerative dermatitis, perforation of the digestive tract, abscessation, suppurative peritonitis and septicaemia. This study is the first investigation of marine debris findings in all three marine mammal species from German waters. It demonstrates the health impacts marine debris can have, including severe suffering and death. The results provide needed information on debris burdens in the North and Baltic Seas for implementing management directives, such as the Marine Strategy Framework Directive (MSFD).
- Published
- 2017
9. Mid-summer abundance estimates of fin whales Balaenoptera physalus around the South Orkney Islands and Elephant Island
- Author
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Helena Herr and S. Viquerat
- Subjects
0106 biological sciences ,Ecology ,Balaenoptera ,biology ,010604 marine biology & hydrobiology ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,lcsh:QK1-989 ,Fin Whales ,Fishery ,Abundance (ecology) ,lcsh:Botany ,lcsh:Zoology ,Whaling ,lcsh:QL1-991 ,Population status ,Geology ,Nature and Landscape Conservation - Abstract
A line-transect distance sampling survey for fin whales Balaenoptera physalus was conducted around Elephant Island and the South Orkney Islands on board a CCAMLR fishing survey for fin fish in January and February 2016. Collected data were used for model-based abundance estimates of fin whales in 2 strata. The minimum average (± SE) density of fin whales was estimated at 0.0268 ± 0.0183 ind. km-2 in a 19750 km2 area around Elephant Island, resulting in a minimum abundance estimate of 528 ± 362 fin whales. In a 13550 km2 area around the South Orkney Islands, we estimated a minimum density of 0.0588 ± 0.0381 ind. km-2 and a minimum abundance of 796 ± 516 ind. The results of this study confirm a westerly extension of a recently described high-density area for fin whales in the West Antarctic Peninsula region. In the light of increasing krill fisheries in the local region, we suggest this area for further studies to assess the potential for conflict between recovering whale populations and emerging industrial interests.
- Published
- 2017
10. Aerial surveys for Antarctic minke whales (
- Author
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Helena, Herr, Natalie, Kelly, Boris, Dorschel, Marcus, Huntemann, Karl-Hermann, Kock, Linn Sophia, Lehnert, Ursula, Siebert, Sacha, Viquerat, Rob, Williams, and Meike, Scheidat
- Subjects
ship‐based helicopter surveys ,density surface models ,marginal ice zone ,Antarctic minke whale distribution ,distance sampling ,Southern Ocean ,Original Research - Abstract
This study investigates the distribution of Antarctic minke whales (AMW) in relation to sea ice concentration and variations therein. Information on AMW densities in the sea ice‐covered parts of the Southern Ocean is required to contextualize abundance estimates obtained from circumpolar shipboard surveys in open waters, suggesting a 30% decline in AMW abundance. Conventional line‐transect shipboard surveys for density estimation are impossible in ice‐covered regions, therefore we used icebreaker‐supported helicopter surveys to obtain information on AMW densities along gradients of 0%–100% of ice concentration. We conducted five helicopter surveys in the Southern Ocean, between 2006 and 2013. Distance sampling data, satellite‐derived sea‐ice data, and bathymetric parameters were used in generalized additive models (GAMs) to produce predictions on how the density of AMWs varied over space and time, and with environmental covariates. Ice concentration, distance to the ice edge and distance from the shelf break were found to describe the distribution of AMWs. Highest densities were predicted at the ice edge and through to medium ice concentrations. Medium densities were found up to 500 km into the ice edge in all concentrations of ice. Very low numbers of AMWs were found in the ice‐free waters of the West Antarctic Peninsula (WAP). A consistent relationship between AMW distribution and sea ice concentration weakens the support for the hypothesis that varying numbers of AMWs in ice‐covered waters were responsible for observed changes in estimated abundance. The potential decline in AMW abundance stresses the need for conservation measures and further studies into the AMW population status. Very low numbers of AMWs recorded in the ice‐free waters along the WAP support the hypothesis that this species is strongly dependent on sea ice and that forecasted sea ice changes have the potential of heavily impacting AMWs.
- Published
- 2019
11. Environmental information for a marine ecosystem research approach for the northern Antarctic Peninsula (RV Polarstern expedition PS81, ANT-XXIX/3)
- Author
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Marcus Huntemann, W. Huneke, Michael Schröder, Boris Dorschel, Astrid Bracher, Helena Herr, Catalina Gebhardt, Julian Gutt, and Oliver Huhn
- Subjects
0106 biological sciences ,Environmental Setting ,geography ,geography.geographical_feature_category ,Krill ,010504 meteorology & atmospheric sciences ,biology ,010604 marine biology & hydrobiology ,biology.organism_classification ,01 natural sciences ,Oceanography ,Marine mammal ,Peninsula ,Benthic zone ,Sea ice ,Bathymetry ,Marine ecosystem ,General Agricultural and Biological Sciences ,0105 earth and related environmental sciences - Abstract
During the austral summer expedition PS81, ANT-XXIX/3 with the German research ice breaker Polarstern in 2013, research was carried out to investigate the role of environmental factors on the distribution of benthic communities and marine mammal and krill densities around the northern tip of the Antarctic Peninsula. For these studies collated in this special issue and studies in this area, we present a collection of environmental parameters with probable influence on the marine ecosystems around the Antarctic Peninsula.
- Published
- 2015
12. Abundance of harbour porpoises (Phocoena phocoena) in the western Baltic, Belt Seas and Kattegat
- Author
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Signe Sveegaard, Anita Gilles, S. Viquerat, Verena Peschko, Helena Herr, Ursula Siebert, and Jonas Teilmann
- Subjects
education.field_of_study ,Distance sampling ,Ecology ,biology ,Population ,Phocoena ,Aquatic Science ,biology.organism_classification ,Oceanography ,Abundance (ecology) ,biology.animal ,Harbour ,Conservation status ,education ,Transect ,computer ,Ecology, Evolution, Behavior and Systematics ,Porpoise ,computer.programming_language - Abstract
In July 2012, a ship-board double-platform line-transect survey was conducted to assess harbour porpoise (Phocoena phocoena) abundance in the Kattegat, Belt Seas and the Western Baltic. A total of 826 km of track lines were surveyed between the 2nd and 21st of July 2012, and 169 observations were made by the primary observers, comprising a total of 230 porpoises. Fifty-seven observations were identified as duplicate sightings observed by both tracker and primary observers and were used to correct for availability and perception bias of the primary detections. Using Mark-Recapture Distance Sampling analysis, we produced a model using the half-normal key function, including sightability as the only covariate to estimate the density and abundance of harbour porpoise within the 51,511 km2 survey area. Estimated detection probability on the transect line, known as g(0), was at 0.571 (±0.074; CV = 0.130). Using a point independence model of the detection function, the abundance of harbour porpoises within the survey area was estimated at 40,475 animals (95 % CI 25,614-65,041, CV = 0.235) with an associated density of 0.786 animals km-2 (95 % CI 0.498-1.242, CV = 0.235) and an average group size of 1.488 animals. These results reflect densities obtained during the SCANS surveys in 1994 and 2005, indicating no significant population trend in the area. However, it should be noted that the survey area covers more than one population and that results are therefore not necessarily reflecting local population trends. Until proper population borders are obtained, the abundance estimate provides baseline data for future monitoring and is an important input to the assessment of the conservation status of harbour porpoises in the area.
- Published
- 2014
13. Der tote Leviathan – ein Streifzug durch die Geschichte des antarktischen Walfangs
- Author
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Helena Herr and Karl-Hermann Kock
- Abstract
In den ersten acht Jahrzehnten des 20. Jahrhunderts wurden in den antarktischen Gewassern uber 2,1 Mio. Wale gefangen; dabei wurde eine Walart nach der anderen dramatisch dezimiert. In diesem Kapitel werden die Geschichte des antarktischen Walfangs und die – lange Zeit vergeblichen – Bemuhungen der Wissenschaftler um seine Regulierung dargestellt, und es wird der heutige Zustand der Bestande mit ersten Anzeichen einer Erholung skizziert.
- Published
- 2016
14. Horizontal niche partitioning of humpback and fin whales around the West Antarctic Peninsula: evidence from a concurrent whale and krill survey
- Author
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Boris Dorschel, Astrid Bracher, W. Huneke, Michael Schröder, Julian Gutt, Karl-Hermann Kock, Volker Siegel, Helena Herr, and S. Viquerat
- Subjects
0106 biological sciences ,Shetland ,Biomass (ecology) ,Krill ,Distance sampling ,Balaenoptera ,Whale ,010604 marine biology & hydrobiology ,Euphausia ,Biology ,Euphausia crystallorophias ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Fishery ,Oceanography ,biology.animal ,14. Life underwater ,General Agricultural and Biological Sciences - Abstract
A dedicated aerial cetacean survey was con- ducted concurrently to a standardised net trawl survey for krill in order to investigate distribution patterns of large whales and different krill species and to investigate relationships of these. Distance sampling data were used to produce density surface models for humpback (Megaptera novaeangliae) and fin whales (Balaenoptera physalus) around the West Antarctic Peninsula (WAP). Abundance for both species was estimated over two strata in the Bransfield Strait and Drake Passage. Distinct distribution patterns suggest horizontal niche partitioning of the two whale species around the WAP, with fin whales aggregating at the shelf edge of the South Shetland Islands in the Drake Passage and humpback whales in the Bransfield Strait. Krill biomass estimated from the concurrent krill survey was used along with CTD data from the same expedition, bathymetric parameters and satellite data on chlorophyll-a and ice concentration to model krill distribution. Comparisons of the predicted distributions of both whale species with the predicted distributions of Euphausia superba, Euphausia crystallorophias and Thysanoessa macrura suggest a complex relationship rather than a straightforward correlation between krill and whales. However, results indicate that fin whales were feeding in an area dominated by T. macrura , while humpback whales were found in areas of higher E. superba biomass. Our results provide abundance estimates for humpback whales and, for the first time, fin whales in the WAP and contribute important information on feeding ecology and habitat use of these two species in the Southern Ocean.
- Published
- 2016
15. Protection of Cetaceans in European Waters—A Case Study on Bottom-Set Gillnet Fisheries within Marine Protected Areas
- Author
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Anita Gilles, Helena Herr, Ursula Siebert, Monika Krivickaite, and Alexander Proelss
- Subjects
Geography, Planning and Development ,Law of the sea ,Exclusive economic zone ,Management, Monitoring, Policy and Law ,International law ,Oceanography ,Fishery ,Geography ,Habitat ,Environmental protection ,Harbour ,Territorial waters ,media_common.cataloged_instance ,Marine protected area ,European union ,Law ,computer ,General Environmental Science ,media_common ,computer.programming_language - Abstract
This article explores the legal regime of the protection of marine species and habitats within European waters by taking the protection of harbour porpoises in the German territorial sea and exclusive economic zone as an example. The analysis is based on a scientific assessment of the occurrence of and the anthropogenic impacts on harbour porpoises in the North Sea. The relationship between the protection of marine species within the European Union (EU) on the one hand and the Common Fisheries Policy of the EU on the other constitutes a classic example of a user-environment conflict. The article explores how such conflicts ought to be solved under the pertinent legal rules.
- Published
- 2011
16. Spatio-temporal associations between harbour porpoise Phocoena phocoena and specific fisheries in the German Bight
- Author
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Ursula Siebert, Heino O. Fock, and Helena Herr
- Subjects
Fishing ,Cetacea ,Phocoena ,Biology ,biology.organism_classification ,Fishery ,Vessel monitoring system ,Bycatch ,Poor cod ,biology.animal ,Fisheries management ,Ecology, Evolution, Behavior and Systematics ,Porpoise ,Nature and Landscape Conservation - Abstract
Interactions between cetaceans and fisheries are a major concern of cetacean conservation and fisheries management, as by-catch and resource competition occur as a result. To assess potential interaction between porpoises and fisheries in the German Bight, high-resolution spatial and temporal data were analysed in order to reveal association patterns between cetaceans and fisheries in the German Exclusive Economic Zone (EEZ) of the North Sea. To facilitate interpretation of resulting patterns, additionally, relationships of fish assemblages were analysed. Vessel monitoring system (VMS) data from 2006 and fisheries surveillance data from 2002 to 2006 were acquired to calculate fishing effort, aerial survey data from 2002 to 2006 to evaluate porpoise distribution, and trawl survey data from 2000 to 2007 to assess fish assemblage. Relationships were analysed in terms of seasonal association and overlap. Results showed that porpoise distribution was positively associated with sandeel fisheries in all seasons and with gillnet fisheries in summer. Overlaps for sandeel and gillnet fisheries were high in summer, while negligible in spring and autumn. In spring, high overlap was found for large beam trawlers targeting sole and plaice. In parallel, porpoise distribution was positively linked to fish assemblage components representing sandeel and poor cod in summer and flatfish in spring. Our results suggest that, especially in summer, resource competition between porpoises and industrial sandeel fisheries is likely and the risk of by-catch in gillnets is increased. In spring, interference with sole and plaice fisheries is to be expected.
- Published
- 2009
17. Counting whales in a challenging, changing environment
- Author
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Andrew S. Brierley, Ted Maksym, Natalie Kelly, Helena Herr, Olaf Boebel, Linn Sophia Lehnert, Jason J. Roberts, Karl-Hermann Kock, Ari S. Friedlaender, Meike Scheidat, Ursula Siebert, Rob Williams, University of St Andrews. School of Biology, University of St Andrews. Marine Alliance for Science & Technology Scotland, University of St Andrews. Scottish Oceans Institute, University of St Andrews. Centre for Research into Ecological & Environmental Modelling, and University of St Andrews. Pelagic Ecology Research Group
- Subjects
0106 biological sciences ,010504 meteorology & atmospheric sciences ,Population Dynamics ,edge ,Antarctic sea ice ,01 natural sciences ,SDG 13 - Climate Action ,Ice Cover ,GC ,abundance ,Multidisciplinary ,geography.geographical_feature_category ,biology ,Data Collection ,ocean ,shelf ,GC Oceanography ,Conservation of Natural Resources ,Krill ,Climate Change ,Oceans and Seas ,Climate change ,Antarctic Regions ,Article ,biology.animal ,Sea ice ,Animals ,Marine ecosystem ,Whaling ,Minke whale ,14. Life underwater ,SDG 14 - Life Below Water ,Minke Whale ,Ecosystem ,0105 earth and related environmental sciences ,ecosystem ,Population Density ,geography ,QL ,Whale ,010604 marine biology & hydrobiology ,QL Zoology ,biology.organism_classification ,antarctic sea-ice ,Fishery ,extent ,Vis ,13. Climate action ,Environmental science ,krill - Abstract
Funding: Marie Curie International Incoming Fellowship within the 7th European Community Framework Programme (proposal Nu 253407 (call reference: FP7- PEOPLE-2009-IIF). Estimating abundance of Antarctic minke whales is central to the International Whaling Commission's conservation and management work and understanding impacts of climate change on polar marine ecosystems. Detecting abundance trends is problematic, in part because minke whales are frequently sighted within Antarctic sea ice where navigational safety concerns prevent ships from surveying. Using icebreaker-supported helicopters, we conducted aerial surveys across a gradient of ice conditions to estimate minke whale density in the Weddell Sea. The surveys revealed substantial numbers of whales inside the sea ice. The Antarctic summer sea ice is undergoing rapid regional change in annual extent, distribution, and length of ice-covered season. These trends, along with substantial interannual variability in ice conditions, affect the proportion of whales available to be counted by traditional shipboard surveys. The strong association between whales and the dynamic, changing sea ice requires reexamination of the power to detect trends in whale abundance or predict ecosystem responses to climate change. Publisher PDF
- Published
- 2013
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