Forget not the grey ghosts at your table

In a lull between gales, sun catches the foam on reefs and islets stretching north from Renvyle Point, and the spray exploding at the tip of Inishbofin is a mesmeric, flickering gleam on the horizon. The scene is one that, each October, takes my thoughts out to the grey-seal mothers and their pups curled against the wind and waves on Connacht's outermost islands.

This autumn other images intrude. The storms that guard the seals' isolation at their most vulnerable time of year are also those that drown fishermen. The recent tragedies set a sobering bottom line to any discussion about the long grievance of fishermen towards the seals.

In the 20 years since the notorious massacre of pups on the Inishkea Islands, off Mayo's Mullet peninsula, there have been other illegal culls at the Blaskets and at islands in the Irish Sea, where the Great Saltee, Co Wexford, and Lambay Island, Co Dublin, have sizeable breeding colonies. All round Ireland, fishermen swear seal damage to their catch has got worse, and urge an official "management" programme.

Counting seals is not an easy matter. No up-to-date Ireland-wide estimate of numbers exists, which leaves a 20-year-old figure of 2,000-2,500 still serving as a very uncertain minimum. Pup production at our main west coast colonies seems steady enough (about 150 a year at the Inishkeas, much the same at the Blaskets), and the Saltee and east coast islands add 150 again - but this is only part of the story.

Ireland is at the south-western edge of the grey seal's distribution in the north-east Atlantic - the really big breeding colonies are at huge "seal cities" at islands off Scotland and along undisturbed coasts in Wales. The UK population has been rising at a steady 7 per cent a year, to an estimated 108,500 animals in 1994.

According to an Irish-Welsh EU Interreg study published by the Marine Institute, the Irish and Celtic Seas are home to between 5,200 and 7,000 grey seals, but about 90 per cent of these belong to the Welsh breeding population. They have their pups mostly in caves and at the foot of high cliffs in north Pembrokeshire.

The study also used a photo-ID database to confirm grey seals of all ages move freely across the Irish Sea, perhaps seasonally. On our Atlantic coast, the Inishkeas also receive a big immigration of males from Scotland in the moulting months early in the year, when as many as 2,200 seals may be hauled out on the rocks.

The appetite of the "average" seal has been variously calculated, from 5 kilos a day to 15 kilos. What is eaten varies hugely, too, from one area to another and from one season to the next. Dietary studies in Scotland, for example, have shown sand-eel as the dominant food. In the new Interreg study, the diet of the seals at Lambay was rich in flatfish, especially plaice, scooped up above a muddy seabed. At Ireland's south-east corner, where the bottom gets rocky, the diet swings towards whitefish, including whiting, cod and hake - this on the doorstep of the trawler fleets of Helvick and Dunmore East.

Arguments about the seals' share and what it does to fish stocks are complex when discussed in scientific and economic terms. Where the conflict gets up-close and personal is where high-value inshore fisheries, such as drift-netted salmon, are raided by locally-based seals.

Along the south-east coast a quite new example of this has arisen, directly related to trends in eating. Here, the inshore fishermen are using nylon tangle-nets on the seabed to catch monkfish (really angler-fish), mainly for the restaurant market. Not only affluent diners find monkfish tails a delicacy: the grey seals, too, often treat them as a take-away, leaving just the big, ugly.

In the process, the seals - particularly inexperienced juveniles - can get entangled and drown. Between 1997 and 1998, 18 seals recovered from the Dunmore East tangle-nets (and brought in voluntarily to the Interreg researchers) were only a small fraction of the real casualties, since most bodies fall out of the nets in hauling.

An earlier tangle-net study in Co Cork found almost a third of the monkfish were damaged by seals, but the present one, with more reliable data, finds damage levels no worse, at some 7-10 per cent, than happens when seals chew on hake and cod caught in gill-nets. Twice as much damage is done by crabs and other marine scavengers, and the value of the monkfish eaten by the seals is is about £50 per vessel per month.

The deaths of seals in tangle-nets could yet become a wildlife welfare issue like that of the "by-catch" of dolphins and porpoises killed in netting tuna. The Interreg research team, led by Dr Oliver Kiely of the Coastal Resources Centre at UCC, wants closer figures for the casualties. It has also called for a proper island-wide census of the grey seal, perhaps by aerial survey during the annual moult season, when much of the population is ashore.

Before any "sustainable management strategies" are possible, says the team's report, there must be more transnational, multi-disciplinary research that treats the Irish Sea as an entire ecosystem, with the seals as just one dynamic element living and feeding within it. The variables considered in modelling the impact of seals on fish stocks are already enough to make the head spin, and the proposed whole-system approach would clearly add many more.

The superabundance of the grey seal has its roots in the general protection extended by Britain since 1914, when the species had grown quite scarce around these islands. This has made some people feel that humans are actually neglecting their duty as the seal's only predator (not quite - the killer whale eats seals, but like all "top" predators in nature, it is scarce in numbers).

Culling is the crudest answer, and, say the scientists, many ecological factors may work to frustrate its intentions. Discuss the ethics at your next feed of Monkfish en Matelote, while apologising to the grey, whiskery ghosts at your table.

The Irish-Welsh EU Interreg study, Grey Seals: Status and Monitoring in the Irish and Celtic Seas, is published by and available from the Marine Institute, 80 Harcourt Street, Dublin 2.