MARINElife blog: DFDS Seaways "Cote des Flandres" Dover-Calais (19 January 2019)

Helen Swift and Tom Forster; Research Surveyors for MARINElife (Registered Charity No. 1110884; Registered Company No. 5057367)

Outbound:Dry and partly overcast, very good visibility, South-easterly wind force 4-6, sea state 3-5, some glare.

Return:Dry and partly overcast, very good visibility, South-easterly wind force 4, sea state 2-3, minimal glare.

Summary of sightings:

Marine Mammals:
Harbour porpoise Phocoena phocoena 4
Grey Seal Halichoerus grypus 1

Black-headed Gull Chroicocephalus ridibundus 202
Common Gull Larus canus 49
Cormorant Phalacrocorax carbo 44
Gannet Morus bassanus 113
Great Black-backed Gull Larus marinus 19
Great Skua Stercorarius skua 2
Guillemot Uria aalge 66
Herring Gull Larus argentatus 12
Kittiwake Rissa tridactyla 79
Long-tailed Duck Clangula hyemalis 8
Razorbill Alca torda 136
Unidentified Auk sp. Alcidae 25
Unidentified Gull sp. Laridae 313
Unidentified Larus Gull sp. Larus 226

This felt a very classic winter survey in the Straits of Dover; before the survey began we could see the harbour wall black with roosting Cormorant (at least 390 present) and the harbour mouth a mass of milling gulls of several species defying detailed counting as they swarmed the disturbed waters to pluck up food stirred up by the passing ferries.

Guillemot Peter Howlett 03Starting the formal survey as we left harbour, we went beyond the milling gulls to settle in to the theme of this survey - a constant stream of auks flying or on the water. Interestingly even this early in the year quite a number were now starting to smarten up to into breeding plumage. We saw no large groups instead a constant smattering of Razorbill and Guillemot that kept us constantly busy recording the whole way across.

Razorbill Peter Howlett 04Our most exciting birds of the survey came quickly with 8 Long-tailed Duck flying westwards seen well by Helen (though sadly I could only catch a glimpse of the last of the flock having been trying to count auks). Our first porpoise followed soon after obligingly surfacing beautifully clearly just ahead of the ship to give us and the bridge-crew a great view before slipping back underwater.

As we neared Calais we saw increasing numbers of Gannet, many of them circling to look for food, and became highly suspicious there would be further porpoise about. Sure enough, we soon spotted a group of 3 surfacing. We hoped there might be more given the widespread Gannet activity but didn't see any further despite our searching - as often I wish it were possible to peer beneath the waves to see what else was about.

In the final section in to Calais we once again faced the swirling masses of gulls feeding around the Harbour mouth. As always on these Dover surveys we felt amazed at the variety and density of wildlife in such a small and busy stretch of waters.

Shortly out of Calais we spotted a large dark shape in the water initially thinking it was a cetacean before getting a better view and realising it was a very large bull Grey Seal resting at the surface. Returning was very similar in regard to the bird-life; huge swirl of milling gulls around Calais then a steady stream of auks punctuated by a few Gannet and gulls and two Great Skua heading west.

Our thanks to Captain and the crew of Côte de Flandres for making us welcome and looking after us throughout the survey.

Guillemot (Peter Howlett)
Razorbill (Peter Howlett)