Filming off the Farne Islands in the North Sea, footage captured by the Newcastle University team shows young male seals engaging in underwater physical contests to establish dominance and even underwater mating – a behaviour which until now was believed to only take place on land.

Capturing footage and audio recordings of their underwater lives, the scientists believe the findings could be used to guide seal conservation and management programmes in the future.

Dr Ben Burville, a visiting researcher at Newcastle University, has been observing and recording the underwater behaviour of grey seals for the last 16 years. He said:

“Grey seals are well-known for their sociable nature but little is known about the sounds that they make while displaying different underwater behaviours. This is the first time that we’ve observed juveniles appearing to practice certain types of behaviour so by linking images with high quality recordings we can start to catalogue the range of sounds and activities seals make.” 

Complex underwater behaviour

Nearly 40 % of the world’s population of grey seals live in UK waters and although the Farne Islands have one of the UK’s largest grey seal populations only limited research has been conducted on the islands in the past decades.

The team have identified a location at the Farne Islands that appears to be a specific area for young grey seals to gather. At this site they have recorded a range of behaviours, such as young male seals engaging in physical contests underwater to establish dominance. The research team, based in Newcastle University’s School of Marine Science and Technology, think that this type of underwater competition is then carried through to encounters on land, and is an example of how young seals practice for the future.

The team have also observed mature bull seals using loud, low frequency vocalisations whilst submerged to attract female seals during the mating period.  

Researchers are now investigating the connections between vocalisations and specific behaviour such as underwater mating, fighting between males and play behaviour. By linking sounds to specific behaviours it will allow researchers to use acoustic monitoring in the future to identify aquatic areas that may be important for mating and other social activities.

Dr Per Berggren, research team leader at Newcastle University’s Marine Megafauna Lab, added: “The Farne Islands is the largest breeding ground for grey seals in the North Sea. However, the mortality rate for pups on the Farne Islands have been very high in recent years so improving our understanding of the seals’ behaviour is crucial for future monitoring and conservation of the colony.”