We’d recently had a run of bad luck with MARINElife surveys, having to cancel the last few we had scheduled due to repeated forecasts of strong winds and heavy rain. In fact, we hesitated bidding on this survey, as we had started to think we were cursed! Once again, it looked like history might repeat itself, with Storm Isha due to arrive the weekend of the survey. Thankfully - despite our trepidation - the forecast for the day of the survey remained reasonable, with the stormy weather due to hit the day after. So, it was with great relief and excitement that we made our way down to Dover.
As we approached the port, we could see that the Channel was a bit ‘lumpier’ than we’d hoped – evidently, the wind was picking up sooner than expected, in advance of the approaching storm. On the positive side, it wasn’t raining…so we were confident we would spot birds, even though conditions weren’t great for picking up cetaceans.
After boarding the Côte d’Opale, we were swiftly escorted to the bridge and given a warm welcome by the Captain and officers. While waiting to depart, we were astonished to see the walls of the harbour breakwaters blackened by lines of cormorants. Tom estimated that there was a total of approximately 1,050 birds, but, as we watched, more continued to arrive and tried to muscle their way into the little space remaining on the walls. Presumably these were taking shelter from the prevailing wind.
Once we had left the harbour, we started our survey ‘on effort’. We immediately faced the challenge of trying to record numerous gulls – of a range of species and ages – being buffeted past us towards land within the matter of a few seconds. Realistically, it was impossible to record all of the information and many were simply recorded as ‘Gull spp.’ or ‘Larus spp.’. However, species positively identified included Herring, Lesser Black-backed, Great Black-backed, Mediterranean and Common Gull, plus Kittiwake. Guillemot and Razorbill were also seen in lower numbers. An early highlight of the survey was a close flyby by a Red-Throated Diver – a distinguishing feature of which is its ‘droopy’ neck when in flight.
Within about five minutes, Tom had the first marine mammal sighting of the survey – a solitary Harbour Porpoise. Unfortunately, I didn’t manage to spot this one due to its unobtrusive behaviour and the choppy conditions. But a good start – better than we’d hoped!
Definitely, our most unexpected sighting was a flock of seven Lapwing, seen just a few minutes into the survey. As a terrestrial bird, these are not something we have previously encountered at sea! According to the British Trust for Ornithology (BTO), this is a species that can be affected by severe cold weather, which may cause populations on the Continent to evacuate their traditional wintering areas and move westwards to Britain and Ireland in search of milder conditions. So, we speculate that this is what we were witnessing.
For most of the outbound journey, we continued to record a similar mix of seabird species. Unusually, on this particular survey, the most common gull was the Common Gull – actually living up to its name, for once!
As we came closer to Calais, we started to see Gannet – a relief given their decline due to bird flu. Initially, it appeared these were on the search for food, and then, confirming our suspicions, we witnessed further birds diving into the water. There were also auks sitting on the water, appearing as if they had recently fed. We were suspicious that cetaceans were also present in this feeding frenzy but, despite our best efforts, we did not spot any amongst the swell and numerous ‘white horses’. However, as conditions started to calm, we did see a couple of Harbour Seal logging on the surface.
As we approached the port, we ended our survey to enable the Captain and officers to complete their manoeuvres without distraction. However, we did note a group of 10 additional Harbour Seal that were hauled out on the beach in Calais. These exemplified the very variable colour of this species, being a mixture of shades of brown and grey.
While the ship was docked, we remained on the bridge, refreshing ourselves with a hot beverage and amusing ourselves by watching the wildlife in the harbour. According to Tom, there were only 80 Cormorant on the Calais breakwater – evidently, Dover was much more popular! We also spotted a large group of Black-headed Gull which, somewhat unusually, we had not recorded on the actual survey - clearly, they were all over here!
On the return journey, we recorded a similar mix of species, with the addition of a few Fulmar this time. The number of gulls seen was, once again, extremely impressive! The highlight was a group of three Harbour Porpoise surfacing just 200m from the ship and swimming powerfully against the choppy waves. We suspect there were plenty more porpoise around, as we have previously seen large numbers here at this time of year, but the choppy waves made spotting them extremely difficult.
Our thanks go to the Captains and other crew members of the Côte d’Opale, for making us very welcome and allowing us to gather valuable data for MARINElife.
Helen Swift and Tom Forster, Research Surveyors for MARINElife (Registered Charity No. 1110884; Registered Company No. 5057367)
Weather
Outbound: dry but blustery, good visibility (11-20 km), wind S force 7, dropping to 4 inshore near Calais; sea state 5-6, dropping to 2 inshore near Calais; some glare.
Return: dry but blustery, good visibility (16 - >20 km), wind S force 6-7, rising rapidly at end of survey to force 8-9, sea state 2 inshore near Calais, rising to 7 once away from land; minimal glare.
Summary of sightings
Marine Mammals
Harbour Seal Phoca vitulina 3
Harbour Porpoise Phocoena phocoena 4
Seabirds
Common Gull Larus canus 423
Cormorant Phalacrocorax carbo 26
Fulmar Fulmarus glacialis 5
Gannet Morus bassanus 99
Great Black-backed Gull Larus marinus 9
Great Crested Grebe Podiceps cristatus 1
Guillemot Uria aalge 46
Herring Gull Larus argentatus 58
Kittiwake Rissa tridactyla 57
Lesser Black-backed Gull Larus fuscus 6
Mediterranean Gull Larus melanocephalus 1
Razorbill Alca torda 37
Red-throated Diver Gavia stellata 1
Shag Gulosus aristotelis 1
Unidentified Auk sp. 127
Unidentified Gull sp. 473
Unidentified Larus Gull sp. 121
Terrestrial birds
Lapwing Vanellus vanellus 7