Oh puffing pig fish –
torn between disturbance and
piscine temptations.
Noise pollution from oil and gas drilling platforms can have huge negative impacts upon marine life. However, such rigs can also act as artificial reefs, providing shelter and a hard substrate for predators and prey alike. Moreover trawling isn’t permitted close to rigs, meaning that the seabeds around them are mostly untouched.
Harbour porpoises, Phocoena phocoena, have previously been shown to change their behaviour or avoid areas as a result of unnatural noise levels. Yet a recent study by Tubbert Clausen et al. (2021) has revealed that the temptations of high prey availability can overcome such affects. The team use 21 acoustic loggers, placed on the seabed for up to 2 years to monitor noise levels and harbour porpoise activity.
They found that despite the high noise levels from the largest rig in the Danish North Sea, the porpoises were still found close to the rig, emitting echolocation noises that indicate they were hunting for fish. The platform’s artificial reef effect appeared to increase fish numbers which drew the porpoises closer.
The findings suggest that as platforms come to the end of their lifespans, they could be partially left in place to continue acting as artificial reefs – the rigs-to-reefs concept.
The first line of the sciku refers to two names for the harbour porpoise:
– The ‘pig fish’ from the Medieval Latin porcopiscus, a compound of porcus (pig) and piscus (fish).
– The ‘puffing pig’ which comes from the noise the porpoises makes when surfacing to breathe.
Original research: https://doi.org/10.1002/2688-8319.12055