Sightings Archives: August 2015

MARINElife Survey Report: Liverpool-Belfast 'Stena Mersey' 22nd August 2015

Posted 03 September 2015

Duncan Fyfe and Sian Ponting, marine surveyors for MARINElife
Conditions: Skies overcast with light precipitation early on; sea state 2-3; wind predominantly S-SE

Summary of Species Recorded

Marine Mammals
Bottlenose Dolphin Tursiops truncatus 2
Common Dolphin Delphinius delphis 4
Harbour Porpoise Phocoena phocoena 21
Grey Seal Halichoerus grypus 1
Dolphin sp 7
Seal sp    1    

Fulmar  Fulmarus glacialis 17
Manx Shearwater  Puffinus puffinus 1089
Gannet  Morus bassanus 107
Cormorant  Phalacrocorax carbo 38
Great Skua Stercorarius skua 4
Herring Gull  Larus argentatus 2
Lesser Black-backed Gull  Larus fuscus 38
Great Black-backed Gull  Larus marinus 8
Kittiwake  Rissa tridactyla 42
Common Tern  Sterna hirundo 24
'Commic' Tern  Sterna hirundo/paradisaea 3
Guillemot  Uria aalge 373
Razorbill  Alca torda 2
Auk sp 30

Terrestrial Birds
Hooded Crow  Corvus cornix 1

We began the survey just after the ship was free of the navigation channel in the outer Mersey. The weather turned out to be quite good despite the forecast of rain which really didn't amount to much by the end. Visibility was reduced to around 5-10 miles but given that the sea state barely got above 3 we still had good spotting conditions which were ideal for Sian's first survey. It was good to welcome her on board.

Common Tern Peter Howlett 02Before long we spotted a grey seal watching the ship as we sailed just off the Sefton coast.  There were also a few common tern and lesser black-backed gull in the vicinity. Due to the overcast skies we soon lost sight of land so it became trickier to reference ourselves off the coast.

The first cetacean sighting occurred just over an hour into the survey as four harbour porpoise were seen slowly swimming past.  A few minutes later we encountered some animals that were moving much faster with most robust bodies and displaying the behaviour characteristics of dolphins.  Unfortunately the sighting was brief so we weren't able to make a firm identification as to the species.

The ship took a route around the western side of the Isle of Man and we were able to make out the Calf of Man and Spanish Head on the starboard side. It wasn't long before we encountered a fleeting glimpse of bottlenose dolphin seemingly to appear out of nowhere within 300 metres off the port side.  Soon after a further two harbour porpoise were seen feeding, with circling gannet and Manx shearwater giving their presence away.

As the Isle of Man disappeared behind our hopes were raised as we came across a large very tight mixed groups of gannet, Manx shearwater and kittiwake in what looked like a post feeding frenzy.  We gave the group special attention but couldn't find any cetaceans in the vicinity although a while later we did encounter four feeding common dolphin.

Manx Shearwater Peter Howlett 02The trip was a successful one in terms of cetacean sightings, but the trip really belonged to the many Manx shearwater.  Personally I have never recorded so many in 15 years of MARINElife surveys.  I am usually quite pleased to record a few dozen on any survey but on this run they were constant throughout and in good numbers almost from the word go, with large rafts near the Isle of Man and Belfast.  

Although we recorded a whopping 1089 of these birds I know we must have under recorded birds because we were so busy writing them down!  It is not unusual for MARINElife to record several hundred of these birds during the summer months in the Irish Sea but this was truly amazing. These birds migrate over 10,000 to the South Atlantic every winter and by the end of September there will be few left in the Irish Sea with numbers of sightings likely to be in single figures.

We ended the survey about 30 minutes before disembarkation which gave us enough time for a quick supper before stretching our legs on shore.  Once again our thanks go to the staff and crew of the Stena Mersey who welcomed us on board and helped to make this another enjoyable crossing.

Duncan Fyfe and Sian Ponting, marine surveyors for MARINElife