Temporal Variability in Antarctic Marine Ecosystems: Periodic Fluctuations in the Phocid Seals
Three species of seals around Antarctica have shown quasi-cyclic patterns in some aspect of their biology: the age structure of crabeater seals (Lobodon carcinophagus) around the Antarctic Peninsula has shown strong cohorts separated by 4- to 5-yr intervals; juvenile leopard seals (Hydrurga leptonyx...
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
---|---|
Main Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Canadian Science Publishing
1991
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1139/f91-081 http://www.nrcresearchpress.com/doi/pdf/10.1139/f91-081 |
id |
crcansciencepubl:10.1139/f91-081 |
---|---|
record_format |
openpolar |
spelling |
crcansciencepubl:10.1139/f91-081 2023-12-17T10:21:29+01:00 Temporal Variability in Antarctic Marine Ecosystems: Periodic Fluctuations in the Phocid Seals Testa, J. Ward Oehlert, Gary Ainley, David G. Bengtson, John L. Siniff, Donald B. Laws, Richard M. Rounsevell, David 1991 http://dx.doi.org/10.1139/f91-081 http://www.nrcresearchpress.com/doi/pdf/10.1139/f91-081 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Fisheries and Aquatic Sciences volume 48, issue 4, page 631-639 ISSN 0706-652X 1205-7533 Aquatic Science Ecology, Evolution, Behavior and Systematics journal-article 1991 crcansciencepubl https://doi.org/10.1139/f91-081 2023-11-19T13:39:10Z Three species of seals around Antarctica have shown quasi-cyclic patterns in some aspect of their biology: the age structure of crabeater seals (Lobodon carcinophagus) around the Antarctic Peninsula has shown strong cohorts separated by 4- to 5-yr intervals; juvenile leopard seals (Hydrurga leptonyx) have appeared in unusually large numbers at Macquarie Island, also at 4- to 5-yr intervals; and Weddell seals (Leptonychotes weddellii) in McMurdo Sound have undergone fluctuations in reproductive rate every 4–6 yr. Complex demodulation was used to compare patterns among these three data sets and with the Southern Oscillation Index (SOI). All of the seal data sets showed evidence of cyclical behavior when demodulated at a period of 5 yr. The Weddell seals were generally in phase with the SOI since the Weddell series began in 1970. The leopard seals and SOI were in phase in the 1960's, but thereafter the SOI series led the leopard seal series by about one quarter of a cycle. The crabeater series was more complicated, but similarities with the other data sets also were seen. If these tentative observations are confirmed, they point to large-scale oceanographic variation, possibly related to the El Niño – Southern Oscillation (ENSO), as an important mechanism in Antarctic marine ecosystems. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctica Crabeater Seals Hydrurga leptonyx Leopard Seal Leopard Seals Lobodon carcinophagus Macquarie Island McMurdo Sound Weddell Seals Canadian Science Publishing (via Crossref) Antarctic The Antarctic Antarctic Peninsula McMurdo Sound Weddell Soi ENVELOPE(30.704,30.704,66.481,66.481) Hydrurga ENVELOPE(-61.626,-61.626,-64.145,-64.145) Canadian Journal of Fisheries and Aquatic Sciences 48 4 631 639 |
institution |
Open Polar |
collection |
Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
spellingShingle |
Aquatic Science Ecology, Evolution, Behavior and Systematics Testa, J. Ward Oehlert, Gary Ainley, David G. Bengtson, John L. Siniff, Donald B. Laws, Richard M. Rounsevell, David Temporal Variability in Antarctic Marine Ecosystems: Periodic Fluctuations in the Phocid Seals |
topic_facet |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
description |
Three species of seals around Antarctica have shown quasi-cyclic patterns in some aspect of their biology: the age structure of crabeater seals (Lobodon carcinophagus) around the Antarctic Peninsula has shown strong cohorts separated by 4- to 5-yr intervals; juvenile leopard seals (Hydrurga leptonyx) have appeared in unusually large numbers at Macquarie Island, also at 4- to 5-yr intervals; and Weddell seals (Leptonychotes weddellii) in McMurdo Sound have undergone fluctuations in reproductive rate every 4–6 yr. Complex demodulation was used to compare patterns among these three data sets and with the Southern Oscillation Index (SOI). All of the seal data sets showed evidence of cyclical behavior when demodulated at a period of 5 yr. The Weddell seals were generally in phase with the SOI since the Weddell series began in 1970. The leopard seals and SOI were in phase in the 1960's, but thereafter the SOI series led the leopard seal series by about one quarter of a cycle. The crabeater series was more complicated, but similarities with the other data sets also were seen. If these tentative observations are confirmed, they point to large-scale oceanographic variation, possibly related to the El Niño – Southern Oscillation (ENSO), as an important mechanism in Antarctic marine ecosystems. |
format |
Article in Journal/Newspaper |
author |
Testa, J. Ward Oehlert, Gary Ainley, David G. Bengtson, John L. Siniff, Donald B. Laws, Richard M. Rounsevell, David |
author_facet |
Testa, J. Ward Oehlert, Gary Ainley, David G. Bengtson, John L. Siniff, Donald B. Laws, Richard M. Rounsevell, David |
author_sort |
Testa, J. Ward |
title |
Temporal Variability in Antarctic Marine Ecosystems: Periodic Fluctuations in the Phocid Seals |
title_short |
Temporal Variability in Antarctic Marine Ecosystems: Periodic Fluctuations in the Phocid Seals |
title_full |
Temporal Variability in Antarctic Marine Ecosystems: Periodic Fluctuations in the Phocid Seals |
title_fullStr |
Temporal Variability in Antarctic Marine Ecosystems: Periodic Fluctuations in the Phocid Seals |
title_full_unstemmed |
Temporal Variability in Antarctic Marine Ecosystems: Periodic Fluctuations in the Phocid Seals |
title_sort |
temporal variability in antarctic marine ecosystems: periodic fluctuations in the phocid seals |
publisher |
Canadian Science Publishing |
publishDate |
1991 |
url |
http://dx.doi.org/10.1139/f91-081 http://www.nrcresearchpress.com/doi/pdf/10.1139/f91-081 |
long_lat |
ENVELOPE(30.704,30.704,66.481,66.481) ENVELOPE(-61.626,-61.626,-64.145,-64.145) |
geographic |
Antarctic The Antarctic Antarctic Peninsula McMurdo Sound Weddell Soi Hydrurga |
geographic_facet |
Antarctic The Antarctic Antarctic Peninsula McMurdo Sound Weddell Soi Hydrurga |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica Crabeater Seals Hydrurga leptonyx Leopard Seal Leopard Seals Lobodon carcinophagus Macquarie Island McMurdo Sound Weddell Seals |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica Crabeater Seals Hydrurga leptonyx Leopard Seal Leopard Seals Lobodon carcinophagus Macquarie Island McMurdo Sound Weddell Seals |
op_source |
Canadian Journal of Fisheries and Aquatic Sciences volume 48, issue 4, page 631-639 ISSN 0706-652X 1205-7533 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/f91-081 |
container_title |
Canadian Journal of Fisheries and Aquatic Sciences |
container_volume |
48 |
container_issue |
4 |
container_start_page |
631 |
op_container_end_page |
639 |
_version_ |
1785535125412380672 |