The migrations of East Coast Humpback whales (Megaptera novaeangliae)
Thesis (PhD)--University of Pretoria, 1994. Southern hemisphere hwnpback whales undertake annual migrations from summer Antarctic feeding grounds, to breeding grounds in coastal sub-tropical and tropical waters in winter. En route the whales utilise extreme coastal waters as migratory corridors. Aft...
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ftunivpretoria:oai:repository.up.ac.za:2263/85529 2023-08-27T04:06:19+02:00 The migrations of East Coast Humpback whales (Megaptera novaeangliae) Best, Peter B. Findlay, Kenneth Pierce 2021/09/09 application/pdf https://repository.up.ac.za/handle/2263/85529 en eng University of Pretoria * https://repository.up.ac.za/handle/2263/85529 © 2020 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. UCTD Migrations East Coast Humpback whales Thesis 2021 ftunivpretoria 2023-08-08T00:27:35Z Thesis (PhD)--University of Pretoria, 1994. Southern hemisphere hwnpback whales undertake annual migrations from summer Antarctic feeding grounds, to breeding grounds in coastal sub-tropical and tropical waters in winter. En route the whales utilise extreme coastal waters as migratory corridors. After severe depletion by commercial whaling between 1904 and 1963, the species is showing a recovery off the east coast of southern Africa. The close proximity of the migration to the coast allowed for a recovery - monitoring programme to be carried out through shore-based visual surveys from Cape Vidal, northern Natal. Surveys of the northward migration were undertaken each winter from 1988 to 1991, and a survey of the southward migration was undertaken in 1990. Daily observations were carried out from an approximately 60 m high vantage point on a headland, during which attempts were made to measure migration characteristics for each group observed, including distance offshore, speed and bearing (measured by theodolite) and group size ( estimated by observers and confirmed by interception of groups by ski-boat). Characteristics of the northward migration were unaffected by environmental parameters (sighting conditions, wind speed or direction, and time of day) or interactive parameters (other migration characteristics). Each year's northward migration was comprised of waves, and apart from the distance offshore, there was no difference in the migration characteristic of each wave. Significant differences were found in group size, distance offshore and speed of the northward migration between years. No differences were found between the mean group sizes or speeds of the northward and southward migrations in 1990, although the southward migration was found to be significantly further offshore than its northward counterpart. The measurement of migration characteristics has played an integral part in population estimation, and in the choice of optimum periods to monitor annual abundance. Results of the 1988 and 1989 ... Thesis Antarc* Antarctic Megaptera novaeangliae University of Pretoria: UPSpace Antarctic Vidal ENVELOPE(-62.450,-62.450,-64.867,-64.867) |
institution |
Open Polar |
collection |
University of Pretoria: UPSpace |
op_collection_id |
ftunivpretoria |
language |
English |
topic |
UCTD Migrations East Coast Humpback whales |
spellingShingle |
UCTD Migrations East Coast Humpback whales The migrations of East Coast Humpback whales (Megaptera novaeangliae) |
topic_facet |
UCTD Migrations East Coast Humpback whales |
description |
Thesis (PhD)--University of Pretoria, 1994. Southern hemisphere hwnpback whales undertake annual migrations from summer Antarctic feeding grounds, to breeding grounds in coastal sub-tropical and tropical waters in winter. En route the whales utilise extreme coastal waters as migratory corridors. After severe depletion by commercial whaling between 1904 and 1963, the species is showing a recovery off the east coast of southern Africa. The close proximity of the migration to the coast allowed for a recovery - monitoring programme to be carried out through shore-based visual surveys from Cape Vidal, northern Natal. Surveys of the northward migration were undertaken each winter from 1988 to 1991, and a survey of the southward migration was undertaken in 1990. Daily observations were carried out from an approximately 60 m high vantage point on a headland, during which attempts were made to measure migration characteristics for each group observed, including distance offshore, speed and bearing (measured by theodolite) and group size ( estimated by observers and confirmed by interception of groups by ski-boat). Characteristics of the northward migration were unaffected by environmental parameters (sighting conditions, wind speed or direction, and time of day) or interactive parameters (other migration characteristics). Each year's northward migration was comprised of waves, and apart from the distance offshore, there was no difference in the migration characteristic of each wave. Significant differences were found in group size, distance offshore and speed of the northward migration between years. No differences were found between the mean group sizes or speeds of the northward and southward migrations in 1990, although the southward migration was found to be significantly further offshore than its northward counterpart. The measurement of migration characteristics has played an integral part in population estimation, and in the choice of optimum periods to monitor annual abundance. Results of the 1988 and 1989 ... |
author2 |
Best, Peter B. Findlay, Kenneth Pierce |
format |
Thesis |
title |
The migrations of East Coast Humpback whales (Megaptera novaeangliae) |
title_short |
The migrations of East Coast Humpback whales (Megaptera novaeangliae) |
title_full |
The migrations of East Coast Humpback whales (Megaptera novaeangliae) |
title_fullStr |
The migrations of East Coast Humpback whales (Megaptera novaeangliae) |
title_full_unstemmed |
The migrations of East Coast Humpback whales (Megaptera novaeangliae) |
title_sort |
migrations of east coast humpback whales (megaptera novaeangliae) |
publisher |
University of Pretoria |
publishDate |
2021 |
url |
https://repository.up.ac.za/handle/2263/85529 |
long_lat |
ENVELOPE(-62.450,-62.450,-64.867,-64.867) |
geographic |
Antarctic Vidal |
geographic_facet |
Antarctic Vidal |
genre |
Antarc* Antarctic Megaptera novaeangliae |
genre_facet |
Antarc* Antarctic Megaptera novaeangliae |
op_relation |
* https://repository.up.ac.za/handle/2263/85529 |
op_rights |
© 2020 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. |
_version_ |
1775347144679489536 |