POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY
The focus of this thesis is the population of adult male sperm whales in Bleik Canyon off the coast of northern Norway. Previous studies have shown this population to be an open population with a few individuals present for many years and a large group of exchanging males, mainly younger individuals...
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ftoslouniv:oai:www.duo.uio.no:10852/11613 2023-05-15T17:43:36+02:00 POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY Rødland, Elisabeth Stein Fredriksen og Arne Bjørge 2011 http://hdl.handle.net/10852/11613 http://urn.nb.no/URN:NBN:no-29689 eng eng http://urn.nb.no/URN:NBN:no-29689 Rødland, Elisabeth. POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY . Masteroppgave, University of Oslo, 2011 http://hdl.handle.net/10852/11613 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Rødland, Elisabeth&rft.title=POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY &rft.inst=University of Oslo&rft.date=2011&rft.degree=Masteroppgave URN:NBN:no-29689 137975 114877467 Fulltext https://www.duo.uio.no/bitstream/handle/10852/11613/2/ElisabethRxdlandMSc.pdf VDP::480 Master thesis Masteroppgave 2011 ftoslouniv 2020-06-21T08:41:58Z The focus of this thesis is the population of adult male sperm whales in Bleik Canyon off the coast of northern Norway. Previous studies have shown this population to be an open population with a few individuals present for many years and a large group of exchanging males, mainly younger individuals. My study aims to update the current abundance estimate with data from 1987 to 2010, investigate individuals that are long-time present in the area and highlight some of the concern of using both photo-ID and commercial whalesafaris as platforms for scientific studies. The study supports the results from previous studies and confirms the presence of both transient and resident male sperm whales in Bleik Canyon as a loose feeding aggregation. The number of sighted whales fluctuated between years, and no trend was found. The number of sampling trips only explained about half of the varying number of sightings, and presence of killer whales, pilot whales and a variable food distribution was proposed as other influencing factors. The estimated abundance also fluctuated between years without any trend. An open model with multiple seasonal sightings is suggested to be the most realistic model for the abundance estimates. The presence of male sperm whales in Bleik Canyon is not unique for the Norwegian Sea, as several matches have been found between Bleik Canyon and Malangsdjupet. However, it is unique to have such a high abundance of sperm whales so close to land, which is of great importance for the tourism of this area. Further investigations is needed to reveal the whereabouts of these male sperm whales during winter and whether or not the individuals sighted in Bleik Canyon also has been sighted at other important sperm whale locations, such as the mating grounds of the Azores. Master Thesis Northern Norway Norwegian Sea Physeter macrocephalus Sperm whale Universitet i Oslo: Digitale utgivelser ved UiO (DUO) Bleik ENVELOPE(15.955,15.955,69.273,69.273) Norway Norwegian Sea |
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Open Polar |
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Universitet i Oslo: Digitale utgivelser ved UiO (DUO) |
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ftoslouniv |
language |
English |
topic |
VDP::480 |
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VDP::480 Rødland, Elisabeth POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY |
topic_facet |
VDP::480 |
description |
The focus of this thesis is the population of adult male sperm whales in Bleik Canyon off the coast of northern Norway. Previous studies have shown this population to be an open population with a few individuals present for many years and a large group of exchanging males, mainly younger individuals. My study aims to update the current abundance estimate with data from 1987 to 2010, investigate individuals that are long-time present in the area and highlight some of the concern of using both photo-ID and commercial whalesafaris as platforms for scientific studies. The study supports the results from previous studies and confirms the presence of both transient and resident male sperm whales in Bleik Canyon as a loose feeding aggregation. The number of sighted whales fluctuated between years, and no trend was found. The number of sampling trips only explained about half of the varying number of sightings, and presence of killer whales, pilot whales and a variable food distribution was proposed as other influencing factors. The estimated abundance also fluctuated between years without any trend. An open model with multiple seasonal sightings is suggested to be the most realistic model for the abundance estimates. The presence of male sperm whales in Bleik Canyon is not unique for the Norwegian Sea, as several matches have been found between Bleik Canyon and Malangsdjupet. However, it is unique to have such a high abundance of sperm whales so close to land, which is of great importance for the tourism of this area. Further investigations is needed to reveal the whereabouts of these male sperm whales during winter and whether or not the individuals sighted in Bleik Canyon also has been sighted at other important sperm whale locations, such as the mating grounds of the Azores. |
author2 |
Stein Fredriksen og Arne Bjørge |
format |
Master Thesis |
author |
Rødland, Elisabeth |
author_facet |
Rødland, Elisabeth |
author_sort |
Rødland, Elisabeth |
title |
POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY |
title_short |
POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY |
title_full |
POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY |
title_fullStr |
POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY |
title_full_unstemmed |
POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY |
title_sort |
population estimation of sperm whales (physeter macrocephalus) from bleik canyon, norway |
publishDate |
2011 |
url |
http://hdl.handle.net/10852/11613 http://urn.nb.no/URN:NBN:no-29689 |
long_lat |
ENVELOPE(15.955,15.955,69.273,69.273) |
geographic |
Bleik Norway Norwegian Sea |
geographic_facet |
Bleik Norway Norwegian Sea |
genre |
Northern Norway Norwegian Sea Physeter macrocephalus Sperm whale |
genre_facet |
Northern Norway Norwegian Sea Physeter macrocephalus Sperm whale |
op_relation |
http://urn.nb.no/URN:NBN:no-29689 Rødland, Elisabeth. POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY . Masteroppgave, University of Oslo, 2011 http://hdl.handle.net/10852/11613 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Rødland, Elisabeth&rft.title=POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY &rft.inst=University of Oslo&rft.date=2011&rft.degree=Masteroppgave URN:NBN:no-29689 137975 114877467 Fulltext https://www.duo.uio.no/bitstream/handle/10852/11613/2/ElisabethRxdlandMSc.pdf |
_version_ |
1766145726603067392 |