Geographical, and seasonal variation in the diet of harbour porpoises (<i>Phocoena phocoena</i>) in Icelandic coastal waters
The stomach contents of 1,047 harbour porpoises (Phocoena phocoena) bycaught in gillnets off Iceland were analysed. Most of the samples were obtained southwest (SW) and southeast (SE) of Iceland and the majority were taken in March and April. The sex ratio was biased towards males (63% males), parti...
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| Format: | Article |
| Language: | English |
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Septentrio Academic Publishing
2003-07-01
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| Series: | NAMMCO Scientific Publications |
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| Online Access: | https://septentrio.uit.no/index.php/NAMMCOSP/article/view/2829 |
| _version_ | 1811243881354756096 |
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| author | Gísli A Víkingsson Droplaug Ólafsdóttir Jóhann Sigurjónsson |
| author_facet | Gísli A Víkingsson Droplaug Ólafsdóttir Jóhann Sigurjónsson |
| author_sort | Gísli A Víkingsson |
| collection | DOAJ |
| description | The stomach contents of 1,047 harbour porpoises (Phocoena phocoena) bycaught in gillnets off Iceland were analysed. Most of the samples were obtained southwest (SW) and southeast (SE) of Iceland and the majority were taken in March and April. The sex ratio was biased towards males (63% males), particularly in the SE area (76%). The proportion of sexually mature porpoises was 35% and was higher in the northern part of the study area. Most examined stomachs contained identifiable food remains (97%). More than 40 fish and invertebrate prey taxa were identified.
Overall capelin (Mallotus villosus) comprised the predominant prey, followed by sandeel (Ammodytidae sp.), then gadids, cephalopods and redfish (Sebastes marinus), while other taxa were of less importance. Differences were detected in diet composition among 5 areas around Iceland with redfish and gadids more prominent in the northern areas. Off SW Iceland there was considerable seasonal variation in the porpoise diet, where capelin appeared to be dominant in late winter and spring and sandeel in the summer through early winter. Predominance of capelin in the diet coincided with the spawning migration of capelin from northern waters along the east, south and west coasts of Iceland. Mature females appeared to have a more diverse diet than other reproductive classes. The length distributions of fish consumed by the porpoises ranged from 1 to 51 cm although most fish prey were less than 30 cm. |
| first_indexed | 2024-04-12T14:16:11Z |
| format | Article |
| id | doaj.art-28d9bd1217224b04b41d6d4419ed692d |
| institution | Directory Open Access Journal |
| issn | 1560-2206 2309-2491 |
| language | English |
| last_indexed | 2024-04-12T14:16:11Z |
| publishDate | 2003-07-01 |
| publisher | Septentrio Academic Publishing |
| record_format | Article |
| series | NAMMCO Scientific Publications |
| spelling | doaj.art-28d9bd1217224b04b41d6d4419ed692d2022-12-22T03:29:43ZengSeptentrio Academic PublishingNAMMCO Scientific Publications1560-22062309-24912003-07-015024327010.7557/3.28292622Geographical, and seasonal variation in the diet of harbour porpoises (<i>Phocoena phocoena</i>) in Icelandic coastal watersGísli A Víkingsson0Droplaug Ólafsdóttir1Jóhann Sigurjónsson2Marine Research Institute (MRI), Skúlagata 4, PO Box 121 ReykjavíkMarine Research Institute (MRI), Skúlagata 4, PO Box 121 ReykjavíkMarine Research Institute (MRI), Skúlagata 4, PO Box 121 ReykjavíkThe stomach contents of 1,047 harbour porpoises (Phocoena phocoena) bycaught in gillnets off Iceland were analysed. Most of the samples were obtained southwest (SW) and southeast (SE) of Iceland and the majority were taken in March and April. The sex ratio was biased towards males (63% males), particularly in the SE area (76%). The proportion of sexually mature porpoises was 35% and was higher in the northern part of the study area. Most examined stomachs contained identifiable food remains (97%). More than 40 fish and invertebrate prey taxa were identified. Overall capelin (Mallotus villosus) comprised the predominant prey, followed by sandeel (Ammodytidae sp.), then gadids, cephalopods and redfish (Sebastes marinus), while other taxa were of less importance. Differences were detected in diet composition among 5 areas around Iceland with redfish and gadids more prominent in the northern areas. Off SW Iceland there was considerable seasonal variation in the porpoise diet, where capelin appeared to be dominant in late winter and spring and sandeel in the summer through early winter. Predominance of capelin in the diet coincided with the spawning migration of capelin from northern waters along the east, south and west coasts of Iceland. Mature females appeared to have a more diverse diet than other reproductive classes. The length distributions of fish consumed by the porpoises ranged from 1 to 51 cm although most fish prey were less than 30 cm.https://septentrio.uit.no/index.php/NAMMCOSP/article/view/2829harbour porpoisedietbycatch |
| spellingShingle | Gísli A Víkingsson Droplaug Ólafsdóttir Jóhann Sigurjónsson Geographical, and seasonal variation in the diet of harbour porpoises (<i>Phocoena phocoena</i>) in Icelandic coastal waters NAMMCO Scientific Publications harbour porpoise diet bycatch |
| title | Geographical, and seasonal variation in the diet of harbour porpoises (<i>Phocoena phocoena</i>) in Icelandic coastal waters |
| title_full | Geographical, and seasonal variation in the diet of harbour porpoises (<i>Phocoena phocoena</i>) in Icelandic coastal waters |
| title_fullStr | Geographical, and seasonal variation in the diet of harbour porpoises (<i>Phocoena phocoena</i>) in Icelandic coastal waters |
| title_full_unstemmed | Geographical, and seasonal variation in the diet of harbour porpoises (<i>Phocoena phocoena</i>) in Icelandic coastal waters |
| title_short | Geographical, and seasonal variation in the diet of harbour porpoises (<i>Phocoena phocoena</i>) in Icelandic coastal waters |
| title_sort | geographical and seasonal variation in the diet of harbour porpoises i phocoena phocoena i in icelandic coastal waters |
| topic | harbour porpoise diet bycatch |
| url | https://septentrio.uit.no/index.php/NAMMCOSP/article/view/2829 |
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