Winter habitat use of harbour seals (Phoca vitulina) fitted with Fastloc™GPS/GSM tags in two tidal bays in France

Winter movements and habitat use of harbour seals (Phoca vitulina) were investigated in two tidal bays in France, at the southern limit of their species range in the Northeast Atlantic. We fitted 15 seals with Fastloc™GPS/GSMtags in the Baie du Mont-Saint-Michel (BMSM) and the Baie des Veys (BDV). Tags relayed 20.6±7.1 GPS locations per seal-day, 81% of all dives performed by the seals and 87% of haulouts, during an average tracking duration of 108±56 days. One seal travelled 380 km away from the BMSM but the other seals remained stationary, with 95% and 55% of at-sea locations ≤ 5 km from the haulout sites in BMSM and BDV respectively. Home range sizes were 137 and 161 km² in BMSM and BDV, and core areas’ sizes, 35 and 22 km² respectively. The seals remained very coastally in both sites with 93% and 71% of at-sea locations located in the intertidal zone of BMSM and BDV respectively. Accordingly, dives were shallow with 63% and 61% of dive maximum depths <4 m and 94% and 88% <10 m (in BMSM and BDV respectively). Preferred foraging areas were located in tidal channels in BMSM, sometimes in the vicinity of rocks or mussel farms. In BDV one seal made foraging trips 10-15 km offshore but all other seals repeatedly used coastal areas, often foraging around mussel farms, shipwrecks or intertidal rocks in tidal currents. We suggest that the importance of the tides combined with local features of the topography allow seals to predict prey availability, driving their foraging strategies towards a number of specific coastal areas. These results further illustrate the behavioural plasticity of the species according to habitat and environmental conditions. Fastloc™ GPS/GSM telemetry is particularly well adapted for the study of seals’ habitat use at a fine geographical and temporal scale, as long as they occasionally come close to shore within GSM coverage.

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Trophic niche overlap between sympatric harbour seals ( Phoca vitulina ) and grey seals ( Halichoerus grypus ) at the southern limit of their European range (Eastern English Channel)

Ecology and Evolution ◽

10.1002/ece3.7739 ◽

2021 ◽

Author(s):

Yann Planque ◽

Jérôme Spitz ◽

Matthieu Authier ◽

Gaël Guillou ◽

Cécile Vincent ◽

...

Keyword(s):

Niche Overlap ◽

Phoca Vitulina ◽

Trophic Niche ◽

Halichoerus Grypus ◽

English Channel ◽

Southern Limit ◽

Harbour Seals

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Diet of harbour seals at Mousa, Shetland, during the third quarter of 1994

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s002531540007185x ◽

1997 ◽

Vol 77 (2) ◽

pp. 539-555 ◽

Cited By ~ 3

Author(s):

E.G. Brown ◽

G.J. Pierce

Keyword(s):

Prey Availability ◽

Temporal Trends ◽

Phoca Vitulina ◽

Correction Factors ◽

Fish Size ◽

The Third ◽

Feeding Experiments ◽

Harbour Seals ◽

Trawl Catches ◽

Fish Otoliths

Scats (N=200) of harbour seals (Phoca vitulina) were collected from haul-out sites on the Island of Mousa, south-east Shetland, during July, August and September 1994. A total of 5,531 fish otoliths were identified in scats and measured to reconstruct fish lengths and weight. Gadid fishes dominated the diet of harbour seals on Mousa during the study period, both in terms of weight and the frequency with which they occurred. There was evidence for the existence of temporal trends. Over the period July–September the importance of gadids in the diet increased while that of sandeels declined. These temporal trends are probably associated with changes in prey availability. Comparisons of the size of sandeels, herring and whiting eaten by seals with trawl catches suggest that seals were probably not size-selective, but a corollary of this is that, while otolith size is reduced during passage through seal guts, application of correction factors derived from captive feeding experiments led to over-estimates of fish size.

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Divergent Foraging Strategies of Two Neotropical Migrant Warblers: Implications for Winter Habitat Use

The Auk ◽

10.1093/auk/117.2.381 ◽

2000 ◽

Vol 117 (2) ◽

pp. 381-392 ◽

Cited By ~ 3

Author(s):

Allan M. Strong

Keyword(s):

Habitat Use ◽

Leaf Litter ◽

Foraging Behavior ◽

Foraging Strategies ◽

Habitat Types ◽

Seiurus Aurocapillus ◽

Winter Habitat ◽

Neotropical Migrant ◽

Use Patterns ◽

Limnothlypis Swainsonii

Abstract To address whether foraging strategies affect habitat-use patterns of nonbreeding warblers, I quantified foraging behavior, bill dimensions, and diet (based on regurgitation samples) of Ovenbirds (Seiurus aurocapillus) and Swainson's Warblers (Limnothlypis swainsonii) wintering in three habitats in Jamaica. Ovenbirds primarily gleaned prey from the surface of the leaf litter (95% of foraging maneuvers), resulting in a diet comprised predominantly of ants (62% of all prey items), seeds (18%), and beetles (9%). Swainson's Warblers foraged by lifting leaves (80% of foraging maneuvers), resulting in a significantly different diet dominated by beetles (39%), spiders (22%), and ants (19%). More than 60% of the regurgitation samples from Swainson's Warblers contained orthopterans and/or gecko (Sphaerodactylus goniorhynchus) bones. Averaged across all habitat types, Ovenbirds consumed ants in direct proportion to their abundance based on visual counts of arthropods. Swainson's Warblers consumed beetles more than expected based on the abundance of beetles in visual counts and Berlese funnels. The use of a diversity of habitats by Ovenbirds may be related to their ability to feed opportunistically on ants, which are a widespread, abundant, and reliable resource. In contrast, based on their foraging behavior and diet, Swainson's Warblers may be restricted to habitats with a well-developed canopy and an abundant subsurface leaf-litter fauna.

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Habitat use by harbour seals (Phoca vitulina) in a seasonally ice-covered region, the western Hudson Bay

Polar Biology ◽

10.1007/s00300-012-1274-4 ◽

2012 ◽

Vol 36 (4) ◽

pp. 477-491 ◽

Cited By ~ 13

Author(s):

C. E. Bajzak ◽

W. Bernhardt ◽

A. Mosnier ◽

M. O. Hammill ◽

I. Stirling

Keyword(s):

Habitat Use ◽

Phoca Vitulina ◽

Hudson Bay ◽

Harbour Seals ◽

Western Hudson Bay

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Late-winter habitat use by the Fisher, Pekania pennanti (Erxleben, 1777), in the Boreal Plains Ecozone of northwestern Saskatchewan, Canada

The Canadian Field-Naturalist ◽

10.22621/cfn.v128i3.1607 ◽

2014 ◽

Vol 128 (3) ◽

pp. 272 ◽

Cited By ~ 1

Author(s):

Gilbert Proulx

Keyword(s):

Habitat Use ◽

Deciduous Forest ◽

Late Winter ◽

Larix Laricina ◽

Forest Stands ◽

Habitat Types ◽

Winter Habitat ◽

Boreal Plains ◽

Pekania Pennanti ◽

Crown Closure

Late-winter habitat use by the Fisher, Pekania pennanti (Erxleben, 1777) in northwestern Saskatchewan was assessed in February 2009, 2011, and 2012. A total of 78 Fisher tracks were recorded over 60 300 m of snowshoe surveys. Fisher tracks were significantly less frequent than expected in Tamarack (Larix laricina [Du Roi] K. Koch) stands with > 40% crown closure and mainly 0–10 m trees (P < 0.05) and in open areas. Fishers used other habitat types equal to availability, including muskeg and coniferous, mixed, and deciduous forest stands. Maintaining mosaics of forest stands of different seral stages interspersed with muskeg would meet the late-winter habitat needs of Fishers in the Boreal Plains Ecozone of northwestern Saskatchewan.

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