England’s only resident population of bottlenose dolphins is under serious threat, scientists have warned.

For almost a decade, scientists and conservation groups along the south coast have been working together with citizen scientists to monitor the movements and distribution of the pod, which is regularly seen near Brighton.

The research has enabled them to establish the most detailed picture yet of this population, their movements and social interactions and the challenges they face on a daily basis.

Researchers estimate the pod currently consists of 48 dolphins, which is less than half the size of most coastal bottlenose dolphin populations, and around ten times smaller than a pod known to inhabit the Channel coast of France.

They are under threat from a combination of human activity, environmental pollution and difficulties in rearing young that survive into adulthood.

Their fight for survival is made even more challenging by the fact they inhabit some of the busiest shipping lanes in the world and coastal waters known to suffer from repeated and prolonged spells of pollution and fishing pressure.


The findings have led the researchers to call for urgent measures to protect the population and its habitats or risk the possibility that this group of animals may not survive.

The research is being led by Cornwall Wildlife Trust and scientists at the University of Plymouth to collate and analyse sightings data, through the South Coast Bottlenose Dolphin Consortium.

The study is the result of work by former marine biology research student Shauna Corr, and former marine conservation students Rebecca Dudley and Saskia Duncan, supervised by Dr Simon Ingram.

Dr Ingram, who leads the bottlenose dolphin research project and is senior author on the study, said: “Bottlenose dolphins are highly intelligent and social animals with complex cultures.

“They are known to have some of the closest interactions with humans of any species on the planet, but because they live in the sea, and not on land, they go unseen by most people and we fail to appreciate quite how amazing yet vulnerable they are.

“To see the south coast population decline to extinction would be a local tragedy for the dolphins and for us.”

The Argus: The pod is regularly seen off the coast at BrightonThe pod is regularly seen off the coast at Brighton (Image: PA)

This population of bottlenose dolphins was first documented by scientists in the mid-1990s and became the subject of detailed scientific analysis again in 2017 due to concerns raised by Cornwall Wildlife Trust about their plight and vulnerability to human impacts.

Individual bottlenose dolphins can be identified from their unique fin markings enabling scientists to build up a catalogue of known dolphins which, through repeated sightings, helped the students to track the movements of individual animals over several years.

The repeat sightings revealed that dolphins from this pod travel the coast between North Cornwall and East Sussex, with some individuals known to have travelled up to 760km between sightings.

Thea Taylor, managing director, Sussex Dolphin Project said: "This fantastic research shows the importance of collaboration between organisations to understand Bottlenose Dolphins. In Sussex, we see both this coastal population and transient Atlantic bottlenose dolphins.

"This is the first research article looking at the south coast population to include data from the Sussex Dolphin Project, incorporating sightings from our community of citizen scientists. It shows that we are only beginning to understand this population and there is still so much research to be done to fully identify their main threats. We are hoping that this research is the starting point for protection to be put in place for this iconic species along the south coast before it is too late."

Sussex Dolphin Project is part of the South Coast Bottlenose Dolphin Consortium and its research has been used to inform the Sussex aspect of the data.

The study’s authors hope this information will be used by statutory marine conservation organisations to provide better protection for this highly vulnerable population and to take appropriate measures in order for the pod to survive.

 The study, using citizen science data to assess the vulnerability of bottlenose dolphins to human impacts along England’s south coast, is published in the journal Animal Conservation.