Marine Giants

Encounters of large marine species in UK coastal waters are currently poorly documented beyond fisheries landings and public sightings databases. There is therefore a real need for novel, cost-effective, fishery-independent methods to survey pelagic marine species.

Funded by Natural England and Dorset Wildlife Trust, the Marine Giants project aims to address this method gap by designing and testing a novel drifting baited camera, suitable for surveying large pelagic species.

Method Design

Six drifting camera rigs were designed and built over the course of 2022. They underwent a series of trials in Plymouth Sound, where aspects such as rig buoyancy and bait composition were tested and fine-tuned. These trials successfully attracted and documented diving birds (Guillemots and Razorbills) swimming at a depth of 5m!

Pilot Study in Lyme Bay

In order to better understand the value of these rigs in answering important ecological questions, they were deployed in a pilot study in Lyme Bay in April 2022. The objectives were to compare the pelagic community inside and outside the MPA and at two different depths.

A total of 72 hours of footage was obtained which, once analysed, will fill in crucial evidence gaps surrounding the use of pelagic habitats inside and outside the MPA.

This project has demonstrated the success and value of this novel method in characterising pelagic communities and opens the door to a variety of potential applications:

  • Surveying pelagic communities in areas where mooring is unfavourable or impossible (e.g. over sensitive seabed habitats/ in extremely deep water).
  • In-situ behavioural studies.
  • Providing a snapshot of the entire food web (to accompany visual encounter surveys of cetaceans/ marine mammals).

Following on from this work, we hope to apply this method specifically to elucidate the drivers of critical habitat use in large pelagic species such as elasmobranchs.