Dover-Dunkirk

Sightings Archives: May 2018

MARINElife report: DFDS Seaways ‘Dunkerque Seaways- Dover-Dunkirk 19 May 2018

Posted 25 May 2018

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

Weather
Outbound: Sea state 1, excellent visibility (>20 km), starboard glare during first half of crossing
Return: Sea state 2-3, excellent visibility (>20 km), port-ahead to ahead glare during second half of crossing

Summary of sightings:

Marine Mammals
Grey Seal Halichoerus grypus 3
Harbour Seal Phoca vitulina 2
Unidentified Seal sp.  1
Harbour porpoise Phocoena phocoena 3
Unidentified Dolphin sp.  1

Seabirds
Common Scoter Melanitta nigra 123
Great Crested Grebe Podiceps cristatus 1
Gannet Morus bassanus 54
Fulmar Fulmarus glacialis 5
Shag Phalacrocorax aristotelis 4
Great Skua Stercorarius skua 4
Common Gull Larus canus 6
Great Black-backed Gull Larus marinus 4
Lesser Black-backed Gull Larus fuscus 27
Herring Gull Larus argentatus 17
Kittiwake Rissa tridactyla 103
Sandwich Tern Sterna sandvicensis 8
Common Tern Sterna hirundo 5
Guillemot Uria aalge 9
'Commic' Tern  1
Unidentified Gull sp.  3
Unidentified Larus Gull sp.  4
Unidentified Skua sp.  1
Unidentified Tern sp.  4

Terrestrial birds
Swift Apus apus 1
Swallow Hirundo rustica 3

When we woke on the morning of Saturday 19th May, the nation was buzzing with anticipation about the Royal Wedding and the FA Cup final, which were both taking place that day.  However, Tom and I were instead full of excitement about what we would see on our survey!

We arrived in Dover well ahead of departure and decided to visit the Western Heights viewpoint to the north of the port, where we had fantastic views of the docks, Channel and famed White Cliffs.  The conditions looked extremely promising - an overcast sky with an (almost) flat calm sea.  However, by the time we came to depart, the sky had completely cleared to reveal glorious sunshine - a blessing for Harry and Meghan, who would be experiencing similar weather, but not so good from our perspective since the resulting glare would make it more challenging to spot cetaceans.

Grey Seal Rick Morris 06a
Grey Seal (Library photo: Rick Morris)

Despite the glare, we did see several marine mammals, with three separate sightings of Harbour Porpoise and several sightings of both Grey and Harbour Seal over the course of the survey.  (One of the Harbour Seals was tucking into a fish.)  On the outbound journey, I also spotted the dorsal fin of a dolphin which surfaced just in front of the ship - I suspect it had been deliberately approaching us to bow ride.  Frustratingly, the view I had was so brief that it was not possible to identify the species.

There was a steady flow of seabirds throughout the survey.  As expected, Gannet and Kittiwake were amongst the most common species seen, with smaller numbers of Herring and Lesser Black-Backed Gull.  However, unusually, the most numerous seabird seen was Common Scoter, with most of these individuals comprising a flock of approximately 100 birds seen in flight.

Great Skua Tom Forster 01
Moulting Great Skua (Tom Forster)

There were also some interesting sightings of Great Skua. Around 20 minutes into the outbound journey, we spotted one with unusual large white patches on the secondary feathers of its wings, in addition to the usual 'white flashes' on its primaries.  We are not sure if these were abnormal unpigmented areas or whether, alternatively, the bird was in moult, which apparently can produce such pale areas as the secondary coverts are shed.  Around 40 minutes later we spotted what appeared to be the same bird, judging by the wing pattern - if this were indeed the case, it is remarkable how far ahead of us it had managed to travel in that time, especially given it had been heading behind us when last seen!  Another Great Skua was seen harassing a Herring Gull with the aim of making it relinquish its fish catch - this is a well-known behaviour of this species but not something we had previously witnessed.

On a sad note, we were horrified by the amount of flotsam we saw during the survey, particularly on the outbound journey - in fact, we saw so much that we nearly ran out of space on our recording sheet!  This mostly consisted of plastic litter, particularly plastic sheets.  Unfortunately, this is yet more evidence of the amount of plastic in our oceans.

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