27/09/10 – 36 bottlenose dolphins and seven Atlantic grey seals

9hr start time: 09:17

Weather conditions: sea state 1/2 then 0, visibility >10km, swell light

An unusual day, with the boat heading off early with a BBC film crew – which led to the extended length of the trip. The first sighting of the day was of an Atlantic grey seal spotted swimming in the water at 09:32, after the boat had passed New Quay Head. This was followed by a frustrating two hours, with not a single sighting. However, as the boat made its way south along the Cardigan Bay coast, our first bottlenose dolphin sighting occurred at 11:25 off Aberporth headland. It was of a lone adult, who was thought to be foraging at depth.

The next two sightings, at 11:31 and 11:38 as the boat continued its journey along the coast past Pen-Peles and Pencestyll, were both of an adult and a juvenile bottlenose dolphin, exhibiting deep dives and thus thought to be foraging. Another lone adult bottlenose dolphin was seen foraging at 11:47, at Thraethy-y-mwnt. Sighting six of the day was three minutes later, and was of a mother and calf. They were also foraging, but as they were close to the boat it was possible to take photo’s of their dorsal fins, for photo identification.

As the boat approached Cardigan Island there was a flurry of activity, with four dolphins being sighted within a ten minute period. Two of these animals came and bow-rode with the boat, while the other two continued foraging. The close proximity of these dolphins meant it was an ideal opportunity for more photo identification, and the boat slowed its journey to allow for this. At 12:30 and 12:37 two male Atlantic grey seals were spotted, both in the water. By 12:52 the dolphins that had been spotted earlier had joined up with each other and another twelve individuals, to form a larger group. This consisted of two newborn, a calf, three juveniles and seven adults. The group appeared to be travelling slowly along down the coast, and were in close contact, mingling at the surface. Occasionally individuals were seen leaping or tail-slapping, and at one point one was seen chasing fish at the surface of the water.

After a break for lunch, during which two Atlantic grey seals were seen, at 13:17 and 13:44, the boat continued down the coast and caught up again with the bottlenose dolphins that had been with the boat earlier. They had split into two groups at this point, one of seven individuals and the other with five animals. Both groups were still in close contact but this time also exhibiting foraging behaviour. At this point the hydrophone was dropped into the water, in an attempt to record the dolphins’ echolocation and vocalisations.

After this it was decided to turn the boat around and head back to New Quay. The next sighting, number 18 of the trip, was at 15:58, offshore from Cardigan Island, and was of a group of five bottlenose dolphins. They sped past the boat, travelling in a south-westerly direction. A female Atlantic grey seal was seen at 16:24, two miles offshore from Mwnt. Three bottlenose dolphins, two adults and a juvenile, were seen travelling to the north at 16:37, followed by two dolphins seen 500m away at 16:43, travelling west. A minute later another bottlenose dolphin was seen foraging followed by a sighting at 17:20 of one dolphin 800m off the port bow, which was travelling north. The final, and 24th sighting, of the trip came as the boat was approaching New Quay Head on its way back to the harbour, and was of a female Atlantic grey seal. A long but very satisfactory boat trip!