This post originally appeared on the Two Oceans Aquarium blog, check it out here!

Cape Research and Diver Development (RADD) is a local marine field station specialising in dive training and long-term biodiversity monitoring projects. The Two Oceans Aquarium is pleased to share the Cape ocean community with dedicated citizen scientists and marine conservationists like Cape RADD. Course Director Mike Barron is a marine biologist, conservationist and a PADI Master scuba diving instructor who has travelled the world diving, experiencing many ecosystems and their inhabitants – he has this experience to share: Cape RADD recently organised a BioBlitz at this year’s Cape Town Dive Festival and discovered something very exciting…

But first…What is a BioBlitz?

A BioBlitz is a snapshot insight into the different animals that can be found in a specific area, which is captured by citizen scientists and participants who help record their sightings by taking photos and submitting them to the database.

The findings!

During this year’s Dive Festival, a very interesting observation was recorded right under our noses in the False Bay Yacht Club harbour – meet the dark crowned nudibranch (Polycera hedgpethi)!


Originally described distribution of the species.

A dark crowned nudibranch.


Originally described in California, the only record of this nudibranch in South Africa was observed in Plettenberg Bay in 1982! This is an interesting find and the fact that this species seems to be seen quite consistently around ports and harbours suggests its distribution on the Western Cape coast may not be through natural movements. This find demonstrates how species can be transported by various forms of human transport, mainly as boat ballast stowaways.

Movement of species to new areas can sometimes cause alien species invasions which can destroy native marine community structures. Fortunately, in this case, this species doesn’t seem to have a huge negative effect on its new destination. This exciting range extension find from the CapeRADD BioBlitz is precisely the reason why citizen science and monitoring of marine habitats is so important.

What exactly is Cape RADD?

Cape Research and Diver Development, established in 2017, is a marine research facility which aims to serve as a platform for marine research and scientists in the Cape Town and False Bay region. It is run by two marine biologists Mike Barron and Dylan Irion.


Cape RADD runs research projects which are designed to assist with the scientific monitoring of marine habitats and their biodiversity in this incredible global hotspot, which has more than 3500 endemic marine species!

We are involved with several projects, including assessing the success of the different management strategies in Marine Protected Areas (MPAs), monitoring diversity and abundance of marine species such as white sharks, shark deterrent strategies and community-based citizen science programmes designed to engage, educate and inspire the general public.

Where does Cape RADD work?

The Cape RADD headquarters is situated in Simon’s Town, False Bay. This is an incredible area of study for a multitude of reasons, as it boasts spectacular beauty that features stunning beaches, incredible marine life, and a mountainous backdrop. The coast of the Cape Peninsula is a well-known hot spot for marine diversity, boasting numerous shark, cetacean, seal and fish species, as well as kelp forests, natural reef systems and artificial habitats in the form of shipwrecks.



How can YOU get involved?

Cape RADD offers an experience for citizen scientists to join their marine biology research team for a day. You will learn about the marine ecology and endemic species of the Cape Peninsula, learn about the sharks and whales of False Bay and participate in a fish identification workshop to learn how to ID the fish you are likely to encounter along the coasts. You will get to snorkel, freedive or scuba dive in beautiful locations, where you will assist with collecting biodiversity data for open source scientific databases.

This is an exciting educational experience for you, your family and friends! For more information on this unique experience head to the Cape RADD website or get in touch at

Mike Barron

Mike is a marine biologist/scientist/conservationist and a PADI master scuba diver instructor. He has travelled the world diving and experiencing many ecosystems and their inhabitants. His main interests lie in the field of inter-specific animal behaviour and he has worked on shark deterrents using Killer whale stimuli.


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