Let's pray for the lamprey

Every year, in May, I migrate northward from Spain, where I live, to spend a week fly fishing for brown trout on the River Usk in Wales, UK. This beautiful river, which has long been the haunt of trout and salmon men, is also visited in May by the rare Twaite and Allis shads, tarpon-like fish that spawn in spectacular frenzy where the river passes through the little town from which it takes its name. If they are lucky, the townspeople may also catch sight of another spawning visitor from the sea – one that in a lifetime of walking river banks I had longed, but never managed, to see: the sea lamprey (Petromyzon marinus). Now, having finally knelt by their riverbed nests and watched their efforts to continue their kind, I am moved to nominate lampreys, these most ancient of vertebrates, as a new flagship conservation species on which to focus attention in a world in the throes of a mass extinction. They are unlikely candidates, I know, but their qualifications are good. Across Europe, populations of various lamprey species have suffered serious decline. In his book My Life, Usk's most illustrious citizen, Alfred Russel Wallace, remembers the river's once great abundance of lampreys. Recalling some stone slabs in the river near his childhood home in the Usk hamlet of Llanbadoc, he writes, “...and it was these that formed our favourite fishing stations, where we sometimes found shoals of small lampreys which could be scooped up in basins or old saucepans, and which were then fried for our dinner or supper, to our great enjoyment. I think what we caught must have been the young fish, as my recollection of them is that they were like little eels and not more than six or eight inches long...my recollections must go back to the time when I was just over three”. Wallace was three years old in 1826. I have fished for hours in front of the cottage where he was born, but those lamprey shoals, like the stone slabs, have become a thing of the past. Academic work confirms the losses. Investigations in Germany and Poland, for instance, record dramatic declines in lamprey numbers between 1887 and 1999. “River lamprey [Lampetra fluviatilis] numbers are in critical condition in the German Baltic region”, according to Curator of Ichthyology Ralf Thiel (Biocenter Grindel and Zoological Museum, University of Hamburg, Germany). “Currently, no sea lamprey reproduction site in the area is known. We need to restore habitat where river lampreys still spawn and remove barriers to their movement, to give them more of a chance. This might help sea lampreys too.” In the Great Lakes of North America, however, P marinus is an invasive pest. Accidentally introduced in the late 19th and early 20th centuries via shipping canals, the species' abundance soared as its members fed on lake trout, requiring massive control efforts. These have included the spraying of lampricides, the use of pheromone attractants, and even the sterilization of male lampreys later released to compete for females with “intact” males. “The US and Canada spend millions each year trying to control the numbers of Atlantic sea lampreys in the Great Lakes streams, where they should not be”, explains Professor of Zoology Jim Kitchell (University of Wisconsin, Madison). “But that does not make it any less of a threatened species elsewhere.” It is this very counterpoint that could keep lampreys in the public mind, drawing attention to the plight of European species, as well as threatened North American species such as the Pacific or mountain brook lamprey. No one seems to be indifferent to lampreys. Notable enthusiasts have included England's King Henry I (1068–1135, who died of “a surfeit” of them), and the inhabitants of the village of Arno in northwestern Spain. Each year, on the last Sunday in April, the villagers celebrate the sea lamprey festival, in which the relatively large numbers that still enter the River Miño become a gastronomic attraction. Cooked in their own blood and served with rice, they are regarded as a great delicacy. The Portuguese, French, and Finnish are no less keen, and, in the UK, the people of Gloucester still present British monarchs with lamprey pie on special occasions. In contrast, many game fishermen are notable detractors of lampreys, and not just because the latter feed parasitically on fish stocks. No, even in Usk, fishermen whose fly lines have seen many a season will tell you with a shudder how lampreys, with those horrible suckers, have swum between their legs. I have now seen sea lampreys in the wild, and I confess to being a lamprey lover. I hope my sons will one day take up a fly rod with me and try to delicately land a dry fly on the water in front of Wallace's cottage, but equally I hope they will never be in the shameful position of having to tell their own children that Grandad once saw some of these wonderful creatures before they all disappeared.

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