Seaquest Netsafe

Seaquest Netsafe is all about cetaceans – dolphins, porpoises and whales – and how we can strive to protect them. We have elements of high technology combined with the dedication and time given by many local volunteers. The results of this project will provide us with a much clearer picture of what is really going on around our coastline and work towards a future of much needed protection for these wonderful creatures.

The background…

In the past, Cornwall Wildlife Trust has collected data on cetaceans which highlights the need for us to develop measures to protect these creatures in this region of the UK. For instance, our research into cetacean strandings has shown that there has been a significant increase in standings reports in Cornwall since 1970. In addition, it has been seen that the accidental entanglement in fishing gear (called bycatch) has been the most common cause of death in UK stranded cetaceans subjected to post mortem examination. The fact that Cornwall has the highest level of cetacean strandings and that the seas off Cornwall are some of the most intensively fished in the whole of the UK make it an obvious starting point for pioneering the establishment of bycatch mitigation measures, a key part of the Seaquest Netsafe project.

So what are we proposing to do?

1. Monitor cetacean species at 7 key sites to develop a picture of the distribution, behaviour and movement of the populations.

The latest underwater acoustic monitoring devices (C-PoDs) have been deployed at key sites around the coast to collect data on the presence and behaviour of cetaceans, 24 hours a day. We have also set up a network of volunteer sightings recorders who have been trained to conduct effort-based surveys to collect data on cetaceans seen from the cliffs at sites overlooking where the the C-PoDs have been deployed. The permanent survey sites are at St Austell Bay, the Manacles, Mullion, Rinsey Head near Praa Sands, St Ives, and Boscastle. Using both these surveys methods we aim to get a much more holistic view of cetacean activity throughout the year, as well as a measure of how effective the two types of survey are. At present there are 40 volunteers doing a fantastic job of visually surveying and recording what they see, recording many hundreds of hours of survey data, and getting some fantastic sightings. Data will be analysed and reports produced that will aim to highlight cetacean ‘hotspots’ to inform potential management strategies for cetacean conservation.

2. Gather data to establish the distribution, numbers and causes of cetacean strandings.

Cornwall Wildlife Trust has been collecting strandings records for many years and has built up a dedicated network of volunteers. We aim to develop this area of work by extending the Trust’s Marine Strandings Network (MSN) of volunteers who collect and record information from dead stranded cetaceans. Records of dead cetaceans provide an important source of information about the status and health of these species in our waters. Trends in the number and distribution of strandings can give us clues about the movements and population size of cetacean species. Post-mortem examination yields vital information about the cause of death and also provides information about cetacean biology, ecology and cetacean population health and structure.

3. Trial BEEP (Bycatch Evidence Evaluation Project) methodology

In Cornwall only a small percentage of stranded cetaceans are suitable for post mortem examination. In addition to this, there is currently no accepted method for diagnosing bycatch in cetaceans from observations made on the beach. Consequently, a lot of valuable information from animals that are not subject to post-mortem is lost or ignored and the current data may not reflect the true scale of bycatch mortalities. Cornwall Wildlife Trust has come up with a new methodology we have called BEEP – Bycatch Evidence Evaluation Project – which aims to break new ground by developing a validated method for diagnosing bycatch on the beach, in the absence of post mortems and observer schemes. This will be done by identifying marks which we think might be ‘bycatch indicators’ and then examining a large number of cetacean carcasses which will also undergo post mortem examination. We will then compare the results of our analysis to that of the post mortem examinations to determine which type of ‘marks’ can reliably be used as indicators of bycatch.

4. Pingers trial

Nick Trengenzas fascinating talk on Cornish Dolphins in the Spring 2010 edition of the HMCG newsletter informed you about this interesting little device designed to alert small cetaceans to the presence of fishing nets. Current EU law states that vessels over 12m length setting bottom set static fishing nets must use pingers, however there is no such regulation for smaller inshore fishing vessels. 4 inshore fishing vessels have volunteered over the last 12 months to collect data for this trial, without which the project would have been impossible. The main purpose of the trial was to test the practicalities of deploying pingers on nets, both in terms of safety of crews and as a cetacean deterrent to minimize bycatch. This trial is coming to an end now and the results of the last 12 months data is ready for analysis to determine whether pingers are effective as a bycatch mitigation tool or not. Feedback from fishermen on the practical aspects of pinger use so far has been very good, stating that pingers caused no major problems with their normal fishing activity, though there were some concerns with battery life and cost.

We will bring you more news on these results in future newsletters.

5. Develop management strategies around Cornwall to protect cetaceans and their ecosystem

The aim is that the results of the monitoring and data gathering activities detailed above can be used to inform the implementation of practical protection measures for areas where cetaceans occur in greatest abundance and are currently not protected. The Trust aims to pioneer the development of management strategies for cetacean conservation in Cornwall through working in partnership with, amongst others, the Cornwall Sea Fisheries Committee, the Cornwall MCZ working group, Natural England and Finding Sanctuary.

Ruth Williams, Marine Conservation Officer, Cornwall Wildlife Trust

Extract from HVMCA newsletter No.41 Autumn 2010

© Helford Voluntary Marine Conservation Area