MARINElife Survey Report: Liverpool-Belfast 'Stena Mersey' 28th August 2013

Dave McGrath and Ollie Metcalf, Research Surveyors for MARINElife
Weather: Sunny/overcast; good visibility; wind NW 4 dropping to 0; sea state 3 dropping to 0; precipitation nil

Summary of species recorded

Marine mammals:
Common Dolphin Delphinus delphis 5
Harbour Porpoise Phoceona phocoena 38
Dolphin sp 2
Grey seal Halichoerus grypus 1
Common or Habour Seal  Phoca vitulina 1+ 32 hauled out in Belfast harbour
Seal sp 1

Ocean Sunfish Mola mola    1

Eider Somateria mollissima 19
Common Scoter Melanitta nigra 5
Fulmar Fulmarus glacialis 11
Manx Shearwater Puffinus puffinus 770
Storm Petrel Hydrobates pelagicus 9
Gannet Morus bassanus 181
Cormorant Phalocrocorax carbo 72
Shag Phalococorax aristotelis 1
Great Skua Stercorarius skua 1
Arctic Skua Stercorarius parasiticus 3
Black-headed Gull Chroicocephalus ridibundus 2
Common Gull Larus canus 8
Herring Gull Larus argentatus 31
Lesser Black-backed Gull Larus fuscus 73
Great Black-backed Gull Larus marinus 22
Little Gull Hydrocoloeus minutus 4
Kittiwake Rissa trydactyla 62
Gull sp 450
Sandwich tern Sterna sandvicensis 12
Common Tern Sterna hirundo 483
Arctic Tern Sterna paradisaea 7
'Commic' Tern Sterna hirundo/paradisaea 6
Black Guillemot Cepphus grylle 4
Guillemot Uria aalge 2150
Auk sp     153

Terrestrial Birds:
Sand Martin Riparia riparia 1
Swallow Hirundo rustica 1
Grey Plover Pluvialis squatarola 2
Ringed Plover Charadrius hiaticula 1
Oystercatcher Haematopus ostralegus 142
Canada Goose Branta canadensis     6

We were welcomed on board and shown our cabins by the very friendly crew of the Stena Mersey then taken up to the bridge where we were introduced to the Captain who allowed us to remain while preparations were made for departure.

Almost as soon as our survey had started we were watching a Harbour Porpoise while the boat was manoeuvring away from the dock and we had a short wait in the river while the large ship Star Harmony was piloted in.  Terns from the local nature reserve kept our survey sheet ticking over and had attracted the attention of an Arctic Skua.  Large flocks of gulls and Oystercatcher were roosting on the beach amid Antony Gormley's 'Another Place' statues.

Storm PetrelNot far into our voyage we had a small number of Little Gull and a Grey Seal watched us pass with a wary eye before diving out of sight.  Once out in to the more open sea things quietened down a bit, where the brisk headwind and very choppy sea made finding any of the local Harbour Porpoise very tricky indeed, and indeed we didn't!  
Two Common Dolphin crossed the bow spotted by Ollie and a little further on he briefly saw one, possibly more, dolphin in the distance.  Small numbers of Gannet and Manx Shearwater with a few small rafts of Guillemot kept us busy, while somewhere to our starboard side there was a moulting flock of about 10,000 Common Scoter of which we saw only five!

After we passed the Isle of Man, with the wind having dropped sightings picked up quickly and the sea was suddenly filled with very easy-to-see Harbour Porpoise.  There were so many that for a while were rushed off our feet, and totally underestimating the large rafts of Guillemot as we struggled to keep up with the porpoise sightings.  These were then out-done by three Common Dolphin, while an Ocean Sunfish flopped along in front of us!
Harbour sealsA Great Skua sat malevolently watching us pass on the very still sea, and when a Swallow and a Sand Martin flew in front of the bow, we realised that it would now be easy to pick up any Storm Petrel which might be lurking within ranks of Manx Shearwater and Guillemot.  A tiny black dot in the distance was our first Storm Petrel, and over the next few miles we saw another eight individuals, some pleasingly close to the ship.

Harbour Porpoise continued to be seen and by the end of the survey we had recorded 38 of them. With these cetaceans demanding most of our attention the huge rafts of Guillemot we passed could only be quickly assessed and our final figure of 2150 is likely to have been a substantial underestimate.

Approaching Belfast large numbers of terns were seen again and they had also attracted the attentions of two more Arctic Skua. At the mouth of the harbour down by one of the channel marker buoys we saw four Black Guillemot, one of the feature birds of this survey, with a large family of Eider down on of the small inlets.  In the harbour beyond the dock 32 Harbour Seal were hauled out on the seaweed strewn rocks.

At the end of our survey we thanked Captain Paulo for his hospitality and made our way to our cabins for the overnight return.  Our thanks go to all the officers and crew of the Stena Mersey for making this a very enjoyable survey.  We look forward to working with them again in the future.

Dave McGrath and Ollie Metcalf, Research Surveyors for MARINElife