The rugged west coast of Scotland looks glorious in the sunshine. The turquoise sea is calm but even in July, it’s a chilly 12°C. Armed with my recording kit, snorkelling equipment and my thick wetsuit, I’ve been listening to the marine creatures living in three different Scottish seagrass meadows.

For my marine ecology PhD, I’m investigating the biodiversity of Scottish seagrass meadows which, right now in midsummer, are in full bloom. Unlike seaweed, this marine plant has got flowers, seeds, pollen and underground roots.

Seagrass meadows are buzzing with activity. Sea snails scrape rocks as they eat algae, young fish feed on tiny zooplankton, crabs fight to defend their territories, plus birds, seals and otters hunt for food.

There’s a cacophony of sounds from all of this busy-ness and I’m researching how seagrass soundscapes – that’s the collections of sounds that can be heard in an environment – differ depending on the wildlife living there. Hearing a wider variety of sounds might mean there are more animals in the seagrass and potentially indicate a healthier, more biodiverse seagrass meadow.

Seagrass meadows have declined drastically due to sediment and nutrient runoff from agriculture, coastal development, destructive fishing practices and disease. The UK has lost more than 40% of its seagrass cover, possibly up to 90% compared to pre-industrial levels. Globally, 29% of seagrass has disappeared since the 18th century, and the rate of decline has accelerated, with about 7% lost every year since the 1990s.

Seagrass is an important breeding ground for fish, it improves water quality and acts as a carbon store. So its decline affects the marine creatures living within the habitat, animals further........

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