MARINElife survey report: Dover-Dunkirk 25 July
25 July 2026
It was a clear, sunny morning as I drove down to Dover. The DFDS ferry that I was due to join for the survey was not departing for Dunkirk until noon, but I opted to set off from home early in case of heavy traffic on the approaches to the port, the school holidays having just started. In the event, the journey was free of hold-ups, and I had plenty of time to go over the identification of terns while I waited to board the ferry, and to watch the gulls which were scoping out feeding opportunities among the waiting tourists.
Once the Delft Seaways was ready to receive us, the assembled cars and lorries were invited to embark. As usual, I parked in our own special place on the car deck, well away from the tourist cars that would be disembarking on our arrival in France. Having reported to reception, I was taken up to the bridge and welcomed by Captain Doyle. Once the ship was underway and had left the shelter of the harbour, the survey began.

The sea was a little lively for sightings of Harbour Porpoise and other cetaceans, but wind speeds were fairly low and atmospheric visibility was good. An adult Great Black-backed Gull was the first record of the survey, followed by the first Gannet of the day, several Herring Gull, including an immature bird, and a lone Kittiwake. Then I glimpsed a dark shape in the water abut 250 metres off the port bow, which soon surfaced briefly once more, this time observed through my binoculars. It was a Harbour Porpoise, its characteristic small triangular dorsal fin visible fleetingly among the waves.
Nearing the French coast, several Sandwich Tern were recorded, along with a single Fulmar, Lesser Black-backed Gull and a pair of pigeons, in addition to Herring Gull, Great Black-backed Gull, Kittiwake and Cormorant.

On the return crossing, the wind had strengthened and the sea state was higher, with frequent whitecaps and long lines of spume on the waves. The same bird species were recorded as during the outward journey, with the addition of several Common Tern. Overall numbers of birds were fairly low, which is often the case at this time of year on the Dover survey routes, but low numbers do not detract from the importance of a survey, as each one helps build a picture of seasonal distribution and abundance.
There was no shortage of birds as we entered the port at Dover, with two flocks of several hundred gulls feeding on items stirred up by passing vessels just outside the harbour walls, but these were not recorded as part of the survey due their clear association with the port.
Thanks to Captain Christopher Doyle, his officers and crew for their warm welcome and to DFDS for supporting and facilitating our surveys.
Pat Hatch, Research Surveyor for MARINElife (Registered Charity No. 1110884; Registered Company No. 5057367)
Weather
Outbound: Dry and sunny, wind SW, sea state 2-3, good visibility
Return: Dry and sunny, wind SW, sea state 4-5, good visibility
Summary of sightings
Seabirds
‘CommicTern’ Sterna hirundo/paradisaea 2
Common Tern Sterna hirundo 4
Cormorant Phalacrocorax carbo 4
Fulmar Fulmarus glacialis 2
Gannet Morus bassanus 2
Great Black-backed Gull Larus marinus 13
Herring Gull Larus argentatus 11
Kittiwake Rissa tridactyla 5
Lesser Black-backed Gull Larus fuscus 4
Sandwich Tern Thalasseus sandvicensis 7
Larus sp. 11
Tern sp. 1
Marine Mammals
Harbour Porpoise Phocoena phocoena 1

