Ban or no ban, it will be a long way back for eel stocks

ANOTHER LIFE:'THE EEL," asserted Senator David Norris in February, "is an interesting fish, although it is hardly like a fish. It is somewhere between a fish and an animal such as a snake." Thus informed, his fellow Senators sat back to learn why so urbane a colleague should concern himself with Anguilla anguilla,other than in Joyce's Inisfail, where lovely maidens played with "drafts" of the creature, along with crans of herrings and creels of fingerlings.

But the Senator, as he has recently protested to the media, dwells also in the non-fiction, burly world, where he has been lobbied for support by the regional fishing boards and the eel fishermen of the Shannon.

The eels of western Europe may be in sharp decline, but why has Ireland rushed to a complete ban on their fishery, due to take effect in a few weeks’ time? As the netsmen see it, an EU directive would be satisfied with far less, and Irish eels, in any case, supply a mere 2 per cent of the market. “There is something almost masochistic about this,” agreed the Senator, “that I do not understand.”

Fianna Fáil’s Seán Power, then junior minister for natural resources, did his best. What the EU wanted were national plans to achieve a final escape to the Atlantic of 40 per cent of the “biomass” of adults that used to swim off to breed in the Sargasso before the collapse in stocks began.

According to the department’s report, the new management actions to achieve this somewhat conjectural aim could take up to 90 years and four generations of eels to achieve. Besides, said the minister (and I interpret freely here) anything less than a total ban would cost too much in countering the ingenuities of some in the eel-fishing fraternity. Losing an eel licence, moreover, would warrant no compensation for the almost 300 fishermen, but there could be different work in restoring the fortunes of their quarry.

So severe has been the decline in the volume of young glass eels, elvers, or “bootlace” eels returning to Europe’s rivers over the past 25 years that, even with a total ban, the stock of adults in Ireland’s inland waters is expected to continue falling for at least the next decade. Unlike salmon, eels have no loyalty to particular rivers. Their collapse has, however, drawn dramatic attention to the damaging role of Ireland’s hydroelectric dams, both in the ascent of elvers and downward migration of adult silver eels.

As described in the new national management plan, almost half the inland “wetted habitat” available to Ireland’s eels is above major barriers – six big hydropower installations on the Shannon, Erne, Liffey, Lee, Clady/Crolly and Ballysadare. A great swathe of rivers and lakes in the western midlands is upstream of hydropower stations, few of which, if any, have a bypass channel fitted for the ascent of young eels, which are incapable of jumping or swimming through strong laminar flows. And when the adult silver eels migrate downstream in autumn, the mesh of the rubbish-screens across the water racing to the turbines is too wide to hold them out.

The problem exists across Europe, where the mincing of silver eels in turbines has been put as high as 50 per cent. One solution is to close down the turbines for short periods at the peak of the autumn migration. But how can this be forecast? What Ireland’s eels want for their big exodus is, ideally, several black, Valkyrian nights of storm and rain, presaged by pulsing microseisms of low pressure. Even without such weather, however, the eels show a pre-migration restlessness that predicts their movement downstream.

This can now be detected by a system called Migromat, in which the behaviour of eels in a tank holding water from the river is registered automatically. Trials in Europe suggest this early warning works with remarkable precision and could be used to cut turbine deaths quite substantially. The ESB is looking into it, together with NUI Galway and Electricité de France.

Meanwhile, the board is planning the capture of migrating eels at various points on the catchments of Shannon, Erne and Lee and their release downstream – a “trap and transport” operation that could employ many eel fishermen. New, small hydropower schemes (several have been proposed for Co Kerry) will need the risks to eels included in their Environmental Impact Assessment. There are also guidelines for proper upstream passes for elvers (who happily wriggle up through moss-covered rocks), and efficient screens to save the autumn migrants.

Little is certain about the reasons for the eels’ great decline.

Along with ocean changes from global warming, there is the impact of a nematode worm, Anguillicola,that has infected eels throughout the North Atlantic region. Damaging the air bladder, it may be wrecking the eels' buoyancy on the long Atlantic journey to breed.

But letting them out and back, unfished and unhindered, also seems worth a try.

EYE ON NATURE

While walking across the fields I heard a rapid drumming coming from oak woods that border the farm. On investigation I caught a glimpse of a black and white bird disappearing further into the trees. On checking books the nearest I could get to an identification was a woodpecker. Could this be possible?

Stephen McCarthy, Thomastown, Co Kilkenny

The great spotted woodpecker, once a rare winter visitor, seems now to have become established in the south and east.

On April 2nd I saw a bird on my apple tree which I thought at first was a sparrowhawk. It had brightly barred underparts, upperbody, wings and long tail also barred but slightly reddish in hue and outlined in white, head grey, bill short and pretty straight. On checking my bird books it looked like a cuckoo, but in an urban garden?

Deirdre Concannon, Raheny, Dublin, 5

It was a female cuckoo, probably looking for a nest in which to lay her egg.

We noticed a pink worm swimming in the shallows to the front of the island and a good few dead on our slipway.

Rhoda Thombly, Inishlyre, Co Mayo

They are lugworms, but it’s early for mating. Perhaps rising temperature or pollution drove them out of their burrows.

Michael Viney welcomes observations at Thallabawn, Carrowniskey PO, Westport, Co Mayo. E-mail: viney@anu.ie. Include a postal address.