02 May 2014
Whilst on routine patrol off the Inishowen coast in late April the crew of the Lough Bradán came across yet another pod of bottlenose dolphins, we also ran into a very large pod of bottlenose in October 2013. This pod was smaller at between 10-20 individuals with some very large dolphins, possibly females in calf, and they were happy to bow ride the front of the boat for 10-15 minutes.
Bottlenose dolphins eat between 8/15 kg of fish, normally inshore, bottom dwelling fish. They will also take salmon, plaice, eels, small sharks, rays, hermit crabs, shrimps & mullet. They have also been known to take larger, pelagic fish. In captivity they have been recorded taking large fish to the bottom, rubbing them on a rock to break the backbone, remove the head for ease of swallowing.
They usually hunt in co-operative groups, herding and corralling their prey into shallow water and while two stand sentry, they will take turns thrusting into the terrified ball of herring, sprat or mackerel (normal prey off our Irish coasts) and pick them off at their leisure. These feeding frenzies often attract other predators and the bottlenose dolphins’ intelligent ploy benefits the assembled predators and entire shoals of fish can be wiped out in this way.
There is known to be several small pods of dolphins circumnavigating the Irish coast and hopefully next time photo id can be done to identify which group this is. IBIS have currently got a researcher (Suzanne Beck)who has deployed an acoustic receiver in the Inishowen coastal area and with this sighting she should be able to match the vocalisations she has recorded to this group of dolphins. Suzanne will also be listening for other marine mammals such as porpoises, minke whales and even the killer whales that migrate past Inishowen every year.
Click here to see the short video of the Dolphins on patrol