With something as vast and changeable as the ocean, pinning down the mysteries of ocean life seems an intimidating task. But thanks to the tireless work of the Société Jersiaise’s Marine Biology Section, and due to the generous funding of the Howard Davis Farm Trust – a rich and completely accessible catalogue of the species which dwell in local waters is being compiled.
This month’s blog focusses on a key research project being led by Marine Biology Section Member Chris Isaacs, who has been compiling and recording thousands of his marine photographs and videos identifying a plethora of species sighted in Jersey waters. This catalogue and research tool is being uploaded to publicly accessible biodiversity database iNaturalist – you can view Chris’s catalogue so far by clicking here.
Prior to this project, Chris’s images were stored in his own private collection which he would make available on request, but – as they state in their project report – “Chris and other members of the Marine Biology Section felt it would be a worthwhile endeavour to digitise these records into an accessible format, in order to showcase and celebrate the amazing biodiversity in the Jersey coastal environment”

Further to this cataloguing stage, the Section hope that conclusions drawn from the project will be published “to highlight the marine diversity on our shores.”
The project report continues by saying that “the data would be a gold standard in marine species identification on the island that could be used by both local and visiting researchers.”
At the time of writing, Chris has progressed the following:
- Uploaded 3270 records which include 659 species (some which have never been recorded locally or are considered rare in Jersey’s marine environment);
- Uploaded 113 first local records which have been verified by experts;
- Another 50 first local recordings are awaiting verification;
- 7 of the first records have since been recorded by other iNaturalist members;
- 11 of the verified records are the first time these species have ever been recorded on iNaturalist worldwide.
He now has a further 1500 records to upload and he and other Section members continue to add to iNaturalist as they make further sightings.
The sheer scope and detail of Chris’s collection of images has garnered attention from other experts too. The project report states: “Since starting this project, [Chris] has been contacted commending him on the quality of the data and associated images. The creation of the database has already led to the progression of research further afield and will help to raise the profile of Jersey and the impressive biodiversity of the marine environment. The Marine Biology Section hope it will lead to future collaborations. Since creating the iNaturalist page Chris has been approached to assist with a DNA barcoding project.”
Speaking about the environmental and research significance of this project, the report continues: “It is impossible to protect our natural heritage and the marine environment if we do not know what it is we are trying to protect. This work has made a huge amount of information, not previously available, easily accessible to the wider public, other researchers and policy managers.
“The amount of time and effort Chris has put into collecting this information is staggering and we are grateful to the Howard Davis Farm Trust for financially supporting this project, enabling the information to be shared. We look forward to enhancing the new data set in the future.”
The Marine Biology Section are keen proponents of the use of Citizen Science to catalogue and monitor local species, and iNaturalist is a free and easy way for members of the public to contribute to this aim. These records also feed into the local Jersey Biodiversity Centre, and a number of International schemes such as the Global Biodiversity Information Facility (GBIF).

I sat down with the Section to find out about how these records help them in their research and the conservation of the species in Jersey’s waters.
They explained that Jersey marine environments are particularly varied, commenting that: “Jersey is fortunate to have a great range of rich marine habitats that are forever evolving and seasonally changing. With the exposed reefs and beaches on the west coast, the rugged north coast with kelp covered boulders, the tidal plains of the east and southeast coasts, which happens to be our most diverse area, and the offshore reefs with an almost unique set up.
“All of these are surrounded by strong tidal currents, bringing in nutrients and its own marine life, some in the form of plankton, fishes, and jellyfish. Unlike the terrestrial side much of our waters is either unexplored, or unrecorded.”
Because the Section are putting so much effort into making records of species sightings, they can take note of when rare, new or invasive species find themselves in our waters, and this can tell them something about what is going on environmentally. Often, the sightings of these different species “appear to be indicators of warming waters.”
One such species is an unusual creature known as the Nudibranch. The Section members explain: “Doris Verrucosa commonly known as the Warty Doris, yellow in colour, with the mantle covered in small nodules. The species was not known in Jersey until 2023, when it was found on the east and south coasts, then spread on to the west coast, and the Écréhous, but as yet not reported in the other Channel Islands, and apart from the Isle of Wight, it is fairly rare in the British Isles.”
The Section have noted that these recorded sightings of the Warty Doris in Jersey seem to coincide with similar sightings in waters around Holland and France.

This is just one such example, but the Section emphasise that the more records they have, the more conclusions they can draw about changes in our local marine environments.
Chris Isaacs added: “My records document the arrival & colonisation of dozens of invasive species over the last seven years. There is often little that can be done to control marine invasives, but it is critical to monitor them, so we understand the resulting changes to our ecosystem. iNaturalist enables anyone to become an invasive species monitor.
“There are hundreds of hours of high-quality video attached to the records. I have focussed on capturing rare & under recorded species on film, but we also need some footage of the more common species to use for education & awareness. Now the records are catalogued we can look at how we maximise the use of this resource.”
This year, the Section are hoping to use iNaturalist to run a major educational outreach programme.

When talking about other projects she’s been involved with since joining the Société, Dr. Kinnear spoke about Elaborating on these plans, the Section members said: “We will create schemes regarding certain groups of species, with identification details, where to find it, how to recognise it, and similar species to it, and their differences. It will explain how best to record marine life, how the data is used and produced, what projects it is contributing to, locally and nationally. This will assist in monitoring local marine life, highlighting seasonal, and annual trends, and comparisons with other islands, the UK, and Europe.”
They added: “The schemes will encourage students and newcomers to use Citizen Science to learn, benefit, and be trained in such collaborative set ups, resulting in a personal engagement and a sense of ownership with marine habitats, wildlife, and the contribution of data, also helping people get a better knowledge and understanding of the fascinating marine life we encounter. It will enable the Section to reach out to educators, schools, and community groups.”
This, the Section hopes, will also interlink with other major projects they have on the go including marine mammal recording, crab surveys, ormer tagging, eelgrass monitoring, assessments of existing and proposed “No Take Zones”.
For more information about the Marine Biology Section or to get involved with their ongoing and fascinating research, click here.