MARINElife Report: DFDS Dover Seaways Dover-Dunkirk 25 January 2020

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

Weather
Outbound: Clear at first but thick fog extending over the French side of the channel, good visibility briefly at first rapidly dropping to very poor (at worst to just 100m), wind SE force 2-3, sea state 2-3, no glare.

Return: Thick fog, lifting by mid-channel, very poor visibility gradually improving later, wind SE force 2-3, sea state 1-3, no glare.

Summary of sightings:

Marine Mammals
Harbour Seal Phoca vitulina 1
Harbour Porpoise Phocoena phocoena 2

Seabirds
Common Gull Larus canus 4
Cormorant Phalacrocorax carbo 3
Fulmar Fulmarus glacialis 2
Gannet Morus bassanus 275
Great Black-backed Gull Larus marinus 9
Guillemot Uria aalge 7
Herring Gull Larus argentatus 50
Kittiwake Rissa tridactyla 23
Mediterranean Gull Larus melanocephalus 3
Red-throated Diver Gavia stellata 6
Auk sp.  17
Larus Gull sp.  155

Terrestrial birds
Rock Dove/Feral Pigeon Columba livia 1

The weather forecast in advance of this survey looked very promising; dry, overcast and with light winds… perfect conditions for the survey. Unfortunately, it was not to be. Driving down through mist and low cloud in Surrey and Kent we began to worry about visibility but were initially reassured when we crested the downs at Dover to see the Channel looking calm and clear; sadly this did not last. After a prompt departure the usual winter mix of birds began coming thick and fast with auks, a good mix of gulls, Gannet and Cormorant soon seen. The highlights of this phase of the survey were a Harbour Seal (appropriately, just outside of the harbour) and six Red-throated Diver which seemed to be about in good numbers (this was our personal best total yet from this route and in only a short space of time).

Gannet Carol Farmer-Wright 07a
Gannet (Library photo: Carol Farmer-Wright)

Unfortunately, after 30 minutes of the survey we started to encounter mist banks. At first, these were thin and swiftly passed through, sometimes revealing unexpected sights such as a resting group of about 200 Gannet and 150 gulls, looking like they had recently finished a feeding frenzy. We were excited that mist aside, conditions seemed good and it certainly seemed like there was lots of activity about but, just as we started to hope for some cetaceans the fog intervened. A large fog bank loomed across our course and though looking no different to those we had been passing through, this one proved to be solid, dense fog. We continued to survey and hoped it would thin but it did not. Though periodically seeing a few seabirds (their colours looking very odd in the distorting flat grey light of the fog) it was rather frustrating. Given the fog we had to leave the bridge well in advance of the approach to Dunkirk and similarly could not restart until we had departed the port and approach channel.

Harbour Porpoise Peter Howlett 16b
Harbour Porpoise (Library photo: Peter Howlett)

Our return continued through thick fog but as we approached mid-channel this started to thin. Amidst the thinning fog we finally got our reward for perseverance, as a pair of Harbour Porpoise surfaced close in to starboard, giving us beautiful views. By this point, light was beginning to fade and frustratingly, as conditions continued to clear from the mist, the dimming dusk light forced us to finish. Looking back, we actually saw quite a bit in spite of the fog, reflecting how active this area is at this time of year. It is tantalising though to wonder how much more must have been around hidden behind the veils of fog.

Our thanks to Captain Mills and the crew of Dover Seaways for making us welcome and looking after us throughout the survey.