| Abstract: | We visually observed 1,251 dives, of 14 sea otters instrumented with TDRs in southeast Alaska, and used attribute values from observed dives to classify 180,848 recorded dives as foraging (0.64), or traveling (0.36). Foraging dives were significantly deeper, with longer durations, bottom times, and postdive surface intervals, and greater descent and ascent rates, compared to traveling dives. Most foraging occurred in depths between 2 and 30 m (0.84), although 0.16 of all foraging was between 30 and 100 m. Nine animals, including all five males, demonstrated bimodal patterns in foraging depths, with peaks between 5 and 15 m and 30 and 60 m, whereas five of nine females foraged at an average depth of 10 m. Mean shallow foraging depth was 8 m, and mean deep foraging depth was 44 m. Maximum foraging depths averaged 61 m (54 and 82 for females and males, respectively) and ranged from 35 to 100 m. Female sea otters dove to depths 20 m on 0.85 of their foraging dives while male sea otters dove to depths 45 m on 0.50 of their foraging dives. Less than 0.02 of all foraging dives were >55 m, suggesting that effects of sea otter foraging on nearshore marine communities should diminish at greater depths. However, recolonization of vacant habitat by high densities of adult male sea otters may result in initial reductions of some prey species at depths >55 m. |
| Genre: | Article |
| ProdID: | 1013530 |
| Citation Author: | Bodkin, J. L.; Esslinger, G. G.; Monson, D. H. |
| Citation Contributing Office: | Alaska Biological Science Center |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 321 |
| Citation Issue: | 2 |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Marine Mammal Science |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | APR |
| Citation No Pagination: | |
| Citation Number Of Pages: | 17 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | pp. 305-321 |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Foraging depths of sea otters and implications to coastal marine communities; 2004; Article; Journal; Marine Mammal Science; Bodkin, J. L.; Esslinger, G. G.; Monson, D. H. |
| Citation Start Page: | 305 |
| Citation Volume: | 20 |
| Citation Year: | 2004 |
| Type: | citation/reference |
| Text: | Foraging depths of sea otters and implications to coastal marine communities; 2004; Article; Journal; Marine Mammal Science; Bodkin, J. L.; Esslinger, G. G.; Monson, D. H. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Thu, 1 Jan 2004 00:00 -0600 |
| Publisher: | |
