Seasonal abundance of and estimated food consumption by cetaceans in Icelandic and adjacent waters
The consumption of fish, cephalopods and planktonic crustaceans by cetaceans in Icelandic and adjacent waters was estimated. The estimates were based on (i) abundance estimates from recent sighting surveys (NASS-87,89,95); (ii) seasonal variation in abun-dance es t imated f rom s igh t ings and /or...
| Main Authors: | , |
|---|---|
| Other Authors: | |
| Format: | Text |
| Language: | English |
| Published: |
1997
|
| Subjects: | |
| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.485.7637 http://journal.nafo.int/J22/Sigurjonsson.pdf |
| Summary: | The consumption of fish, cephalopods and planktonic crustaceans by cetaceans in Icelandic and adjacent waters was estimated. The estimates were based on (i) abundance estimates from recent sighting surveys (NASS-87,89,95); (ii) seasonal variation in abun-dance es t imated f rom s igh t ings and /or ca tch da ta f rom whal ing vesse l s; and (iii) consumption rates calculated from the estimated biomass of cetaceans in the area throughout the year. A large number of assumptions had to be made, and these calcula-tions were mainly intended to give an idea of the possible magnitude of consumption as well as to be a guidance for further research in this field. The total food consumption was estimated as 6.3 million tons in a smaller area defined as Icelandic and adjacent waters, and 8.8 million tons in the larger area north of 60oN. Considering total consumption, fin whales (Balaenoptera physalus) and minke whales (B. acutorostrata) were the largest consumers in the area, followed by long-finned pilot whales (Globicephala melas) and northern bottlenose whales (Hyperoodon ampullatus). Crustaceans comprise around 50% of the total consumption within the study area while finfish and cephalopods comprised 27 % and 22%, respectively, in the large area. Minke whales were the largest consumers of finfish, consuming more than 1 million tons of fish in Icelandic and adjacent waters. Key words: feeding, food, Iceland area, whales |
|---|