White-Tailed Eagles on the Isle of Mull

Breeding Season Diet

As in previous years, the diet was studied through the collection of prey remains from nests after young had fledged. In total over 800 items were collected from 22 successful nest sites. The diet was very broad with over 40 species of bird, mammal and fish recorded (see table). However, despite the range of items recorded a few species dominated – mainly sea birds. Fulmars were the most common item contributing almost 50% of all items recorded. Shags, auks and gulls were also common items.

On the Western Isles at least 98 fulmars were recorded at one site, whilst 40 guillemots were recorded at another site on Skye. Some of the more unusual items recorded were a mink, a diver species, and a cuckoo.

There are some regional dietary trends emerging with mammals, particularly hares, and strandline birds appearing most frequently at Mull sites, whilst on Skye and the Western Isles the majority of prey items are sea birds. Fish were recorded at most sites but as most fish bones are small and may be digested by eaglets, this prey group is likely to be under-represented in this type of dietary analysis. Outside the breeding season, the diet of both adult and immature birds is known to include a large proportion of sheep and deer carrion.

Bird species	Mammals	Fish
Diver sp.	Brown Rat	Lumpsucker
Fulmar	Mountain Hare	Mackerel
Manx Shearwater	Irish Hare	Dogfish sp.
Gannet	Rabbit	Ling
Cormorant	Mink	Cod
Shag	Lamb	Hake
Grey Heron	Roe Deer calf	Conger Eel
Greylag Goose	Red Deer calf
Mallard
Eider
Shellduck
Red-breasted merganser
Red Grouse
Pheasant
Oystercatcher
Curlew
Snipe
Common Gull
Herring Gull
Lesser Black-Backed Gull
Great Black-Backed Gull
Guillemot
Razorbill
Black Guillemot
Puffin
Cuckoo
Mistle Thrush
Raven
Hooded Crow