With dolphins, seals, porpoises and even sharks swimming off our shoreline, Sussex has been designated an Important Marine Mammal Area and a Shoreham-based project is studying the magnificent cetaceans
Look out to sea off the Sussex coast and as well as the occasional tanned tourist, children splashing in the surf and seagulls scavenging for food among the beach picnics, you could spot an abundance of marine life, including porpoises, seals and even the occasional shark.
From Selsey, the most southern tip of West Sussex, to Camber Sands, on the edge of East Sussex, the county's 140-mile coastline is one of the most glorious in the UK. As well as dolphins and basking sharks - the second-largest shark in the world ¬- humpback and minke whales have also been recorded, while thresher sharks have been seen leaping clean out of the water.
There's no need to be afraid though - we're not talking Jaws here. They are harmless — though it’s not recommended to get into the water with the marine life — and are simply enjoying the rich and diverse coastal ecosystem Sussex-by-the-sea now has that includes an incredible chalk reef at Beachy Head and the Seven Sisters, the shingle beaches of Brighton and Worthing, and the recovering kelp beds in the west of the county.
One of the most thrilling species found off our coast is, of course, dolphins. That’s why in 2018 the Sussex Dolphin Project was established. At the time, the Sussex Dolphin Project was part of the Brighton-based World Cetacean Alliance , though it has been an independent voluntary organisation since 2023, leading on research into Sussex cetaceans and creating awareness among the local community on the incredible sea life that's right here off our own shores.
‘Until fairly recently, Sussex has been fairly undervalued when you consider the biodiversity off the coast,’ says Thea Taylor, a marine biologist, and the managing director of the Shoreham-based project. ‘People assume you have to travel to see really cool marine life. You don't — it's right here.’
In fact, in February 2024, the south coast of England was designated an Important Marine Mammal Area (IMMA). Right now, this might not mean a great deal, but it is likely to help Sussex's case when being considered for conservation measures in the future.
The Sussex Dolphin Project is still in its infancy, researching and understanding the marine ecosystem off our shoreline. ‘Until we started to do research in 2021, Sussex's coast was one of the most poorly studied areas in Europe for cetaceans,’ Thea explains. ‘There was no understanding of what we had so we are still very much at the baseline level of research.
‘For such a small area, between the North Sea and the North Atlantic, the English Channel is an incredibly busy area for fishing. If you consider how many fishing boats there are, it gives you an indication how much sea life there is.’
In Sussex we have several different pods of bottlenose dolphins, including an inshore population along the south coast of England between Cornwall and Sussex. There are transient bottlenoses, too, ones that travel around the northeast Atlantic and come in to fish from time to time, along with common and some white beak dolphins. And they’re so spectacular it’s worth taking time out to try and spot them.
Dolphin Spotting in Sussex
Whether you have 30 minutes or three hours to spare, it's easy to observe the sea for dolphins from land, a clifftop, a beach, or a harbour. You just need to know what to look for.
The Sussex Dolphin Project offers Land Watch sessions (£15 for two hours), teaching participants how to become a citizen scientist, which helps the project to collect essential data on where dolphin sightings occur. ‘We're on a really big push to encourage people to do land watch through our group sessions or you can get out and do it on your own or with friends,’ says Thea.
Aside from the obvious signs — resplendent dolphins leaping from waves and fins piercing the water — there are other things to look for when scanning for dolphins. If you see diving gannets or, closer to the shore, seagulls and kittiwakes searching for fish near the top of the water, there's a strong chance dolphins are around.
‘Seabirds congregating in one area, particularly birds picking fish off the surface of the sea, is a really good sign that there are dolphins feeding there, too,’ Thea, 30, says.
Unusual waves where you wouldn’t expect to see them, such as going in the opposite direction of the tide, is another sign. ‘Keep your eyes on an area if you spot white water as you might catch the tail end of a dolphin surfacing. If you see a bottlenose dolphin leap out of the water, it is always a fantastic sight.
‘Adult male bottlenoses are very big, about four metres long, and make a heck of a splash when they come to the surface so it's easy to spot them,’ she says, explaining they’re easier to see when the weather and sea are calm, particularly in late summer when dolphins follow the trail of mackerel inshore. In recent months, regular sightings have been recorded off Brighton, around Rampion Wind Farm — a wind farm south of Shoreham —, off Shoreham Beach and south of Shoreham Port.
The Sussex Dolphin Project collaborates with a network of organisations — the University of Plymouth, Cornwall Wildlife Trust, SeaWatch Foundation, and Chelonia ltd — in the south coast of England to identify individual bottlenose dolphins to help track their location and better understand their behaviours.
‘The dorsal fins of bottlenose dolphins will quite often have nicks and scratches because dolphins are very sociable animals and they use their teeth to touch and play,’ explains Thea.
‘They often grab onto the fin of another dolphin that they are playing or fighting with, which makes these marks. We can use these to identify individual animals and share these images with other organisations and track where they have been around the coastline.’
The coastal population of 48 bottlenose dolphins stay together and don't interact with the transient groups. They're characterised by their inquisitive and intelligent personalities. They're also incredibly sociable — not just with other dolphins but with boats, too. In contrast, harbour porpoises, such as those found at Seven Sisters, are shy and more elusive, and are found on their own or in small groups of two or three.
Thea reveals that Sussex's seal population has increased in recent years, with a number of harbour seals often spotted in Chichester Harbour, West Sussex, while bottlenoses are migrating further east . ‘They used to only really be seen around Cornwall, but now they're heading much further up the English Channel. It's too early to say why this is, but there are some really great conservation initiatives happening in Sussex, so we are hopeful that they are having a positive impact on marine life,’ she says.
Protecting marine biodiversity
Cetaceans – aquatic mammals which include whales, dolphins and porpoises – are among the sea world's top predators and their presence is always a good sign that sea life is thriving. The English Channel's biodiversity is, however, threatened by pollution — sewage, plastic waste and agricultural runoff — as well as supertrawlers. Large fishing vessels in British waters are required to report marine mammal bycatch, such as dolphins, to the Marine Management Organisation within 48 hours, though little data actually exists to suggest the fisheries are self-reporting.
‘Supertrawlers operate outside the 12-mile mark offshore, so they are very much an 'out of sight, out of mind' problem,’ says Thea. ‘These boats are enormous, up to 140 metres long and the mouth of their nets is between 200 and 300 metres wide.
‘During winter, these trawlers are targeting the same species of fish that dolphins target and there is a serious impact of bycatch from those supertrawlers and fisheries. Supertrawlers are poorly monitored so we are keen to get monitoring on these boats, such as CCTV, so we can prove if and how much dolphin, shark and seal bycatch they're catching.’
The Sussex Nearshore Trawling Byelaw, introduced in 2021, bans the use of trawling fishing nets close to the shore between Shoreham and Selsey. Though this byelaw doesn't directly impact dolphins (supertrawlers responsible for dolphin bycatch fish much further out to sea), it is hugely beneficial to the recovery of Sussex's depleted kelp forest.
The coastal area protected by the Sussex Nearshore Trawling Byelaw was once home to a luxuriant kelp forest that supported a wealth of sea life — seabream, bass, cuttlefish and lobster — that dolphins feed on. Following the byelaw's introduction, the Sussex Kelp Recovery project was established to restore an area of roughly 200sqkm of Sussex's swaying brown kelp.
‘The kelp recovery will allow other habitats to come back, such as mussel beds and breeding areas. These are incredibly important sources of food for our dolphins and we are hopefully going to start seeing some quantifiable data to show that byelaw is having a positive impact,’ says Thea.
‘There is some incredible biodiversity out there. Some of my favourites, such as sea slugs, are among the smallest creatures in the ocean. I love gurnards (also known as the east Atlantic red gurnard, is a benthic species of ray-finned fish), too. They are beautiful, with a bright pink-red colour with an iridescent line around the edge of their fin.
‘If you show people what lies off the coast of Sussex, they'd assume it’s the Maldives or somewhere like that, but it's right here.’
