Counting Cornwall's Crustaceans

What a difference a month makes! Port Isaac harbour, bathed in the golden dawn light of an August morning, felt like a world away from the dark, wet and windy scene that greeted me there at 5.30 a.m. on a September Saturday. Even Blue, the fishermen's seagoing dog, looked less than enthusiastic, particularly when he realised that I had forgotten to bring him any biscuits. And this is only September - what will November be like? Mind you, some things don't change; the public conveniences are still shut at that time of the morning, no laughing matter when you have just driven up from Redruth!

So what gets a fishery officer to sea before 9 a.m. in such conditions? The opportunity to get my hands (and my measuring gauge) on crabs and lobsters, lots of them, probably at least 7000 in the last four months. Equally importantly, it's the opportunity to learn, at first hand, the realities of owning and working a potter and earning a living from crustaceans - or shellfish, as they are better known in Cornwall.

Shellfish, including brown crab (Cancer pagurus) and spider crabs (Maia squinado), lobsters (Homarus gammarus) and crayfish (Palinurus vulgaris), accounted for landings into Cornwall of over £4.5 million in 2002, supporting nearly 700 jobs on 400 boats working mainly within the Cornwall Sea Fisheries District out to 6 nautical miles. These are rough estimates, as they do not include landings of more specialised items such as green crabs and velvet swimming crabs, nor do they account for direct sales to pubs, restaurants and private buyers, which command a higher price than first hand sales to fish merchants. Whilst tonnes of shellfish, especially spider crabs, are exported to France and Spain, no Cornish café is without its crab sandwiches and the ever-burgeoning list of Cornish seafood restaurants all boast 'locally caught' lobsters on their menus.

Unlike cod, haddock and other white fish, there are no quotas for shellfish in the UK and many vessels have moved their efforts over to shellfish as quotas for other species have declined. In an attempt to cap this effort, a shellfish licence is currently being introduced throughout the UK, limiting the number of boats that can target these species. Locally, Cornwall Sea Fisheries Committee (CSFC) has run a permit scheme for many years, which monitored, but not restricted, shellfishing effort in our inshore waters. Whilst this scheme provided valuable estimates of the landings of shellfish at various ports, it told us nothing about the true nature of the stocks, as theoretically, only animals over the legal minimum sizes were landed.

In an attempt to fill these gaps in our knowledge and to improve our management of these species, CSFC with funding from Objective One and Cornwall County Council, has embarked on a 3-year survey of inshore shellfish stocks, using my monthly observations of potting activity on six boats based around the Cornish coast. On each trip, I select pots as they are hauled aboard and their contents are thrown into a bongo or basket. The assorted crabs writhe around, attempting to tear off one another's legs and claws, in addition to my fingers, whilst I try and measure the sizes of their carapaces (shells). As lobsters are more easily damaged and more valuable, I often find myself lurching across the deck with one in each hand, each intent on attacking the other as well as me. Records are also made of the sex of each animal, whether or not the females are berried (carrying eggs) and the stage of development of the eggs, the presence of damage or disease and if the animals are moulting or 'soft'. Notes are made of the weather, wind and sea conditions and temperature probes have been attached to a pot belonging to each vessel, to record the ambient water temperature.

As all the boats involved are relatively small, between 7.5 - 9 m in length, space is at a premium and obviously it is essential not to get in the way of fishing operations, particularly when the gear is being shot back into the water. The owner/skippers and crew involved have been really patient and helpful and happy to share their knowledge and understanding of the fishery and the ways in which it changes from month to month and from one area to another. Without this information, it would be too easy to draw conclusions from the data alone, without understanding the wider picture of what makes the fishery work.

At the end of 3 years, I will have amassed a huge amount of data and information, as well as a far better understanding of the nature of this valuable fishery and the people involved in it, hopefully before I have worn out my welcome. Fingers crossed for better weather next time!

Sam Davis
Senior Fisheries Officer, CSF

Extract from HVMCA newsletter No.27 Autumn 2003