The rail family is fairly large worldwide but we have only five breeding species in the UK – the Coot, the Moorhen, the Water Rail, the Corncrake and the Spotted Crake, two of which are doing well and three less so.
Coots (Fulica atra, wingspan 75cm) are principally birds of still waters and extremely pugnacious, including in the winter when we receive thousands of migrants from Northern Europe and punch-ups are regular and ferocious. Despite looking clumsy in the air, migrants can cross the North Sea without too much difficulty.
Only one fifth of eggs laid on the nest just above water level result in fledging young – artificial platforms are confidently used on occasions. In the early stages, with their red heads, the chicks look as if they might have been cooked on gas mark 7 for ten minutes. The parents, like Great Spotted Woodpeckers and various other species, divide a brood between them and rigidly feed only ‘their’ birds.
Coots have a love-hate (mostly hate, though that’s a human term) relationship with Great Crested Grebes (Podiceps cristatus), engaging in disputes and attempting to seize nests.
Moorhens (Gallinula chloropus, wingspan 52cm) are less obvious than Coots and suffer in places from being one of the main prey items of the American Mink (Mustela vison), an unwanted addition to our fauna through carelessness at fur farms and irresponsibility by so-called animal rights activists, many of whom seem to know and care little about the environment whatever they may think about the way humans treat animals in the name of science or fashion.
Mink, which are highly intelligent and tremendously effective predators on land as well as in the water, are found virtually everywhere in lowland England, with serious consequences for native fauna including the charming Water Vole (Arvicola terrestris), which has disappeared from 94 per cent of its former sites over the last 40 years. Legal protection, which the Water Vole has, counts for little when an unnatural non-native predator preys on them. While trapping can be effective providing it is continuous – if a territory is left open, another Mink will turn up – the best hope for keeping them in check is the return of the Otter (Lutra lutra, 100cm), which is much bigger and will not tolerate Mink in its home area.
Apart from fish, Otters feed on crustaceans, water birds, frogs and voles. They can use their whiskers as sensing organs underwater, to monitor the movements of prey. The Otters shown on this page are captive at The British Wildlife Centre in Surrey. A few years ago it might have been naive to imagine that Otters would stage a comeback in the Home Counties, but prospects are looking better, thanks to the efforts of conservation groups and the Environment Agency, a tremendous force for good, albeit one that is under-funded. Otters are listed as Vulnerable by the 2000 IUCN Red List. They have become extinct in much of their range, with many populations still diminishing. They are strictly protected by the Wildlife and Countryside Act (1981) and cannot be killed, kept or sold without a licence.
Moorhens are commoner on shallow lowland rivers than Coots, but are equally at home on ponds and can reach sizeable numbers if the feeding is good, both from people and in pasture nearby – much of their feeding is done on land. They breed very much as a family, with earlier broods helping in the rearing of later ones.
One rarity that turned up at Reigate in Surrey for two winters around the turn of the millennium was a Moorhen without any red on the beak or legs. Most red and orange colours in birds are produced by carotenoid pigments, which are a class of natural fat-soluble pigments found principally in plants, in algae and in photosynthetic bacteria. The yellow carotenoid is lutein, and the red one, astaxantin, is manufactured from the lutein.
An absence of these pigments from the diet could result in no red on a Moorhen, but as the other birds on the pond all had the customary markings, this was hardly feasible. The likely solution was an uncommon deficiency in this particular individual.
Birds are unable to synthesise carotenoids, but re-synthesise the pigment and incorporate it into their plumage, bill etc. In a few individuals the final synthesis process to produce the red pigment may be inhibited for some reason, causing the carotenoids to remain yellow.
Clearly this Moorhen was an aberration and an undoubted rarity, but remarkably few of the public going to the pond realised there was anything different about the bird. The more we see, the less we notice.
Water Rails (Rallus aquaticus, wingspan 42cm) are retaining a hold in lowland England, unlike the Corncrake or Land Rail (Crex crex), which has been blitzed from nearly all of the UK by modern intensive agricultural methods, especially the development of mechanised mowing. However, they do seem to be making something of a comeback in the North, helped by conservation bodies and enthusiastic farmers.
Spotted Crakes (Porzana porzana) used to be local but fairly common in the early 19th century but are now only sporadic breeders with fewer than 100 calling males nationally.
Water Rails are notoriously secretive, with the ability to shrink to what seems the size of a pencil in width when moving silently through a reedbed without disturbing the vegetation. They require dense cover by water, a habitat which land reclamation reduced wholesale up to the 1960s.
As a result, their breeding numbers are hard to calculate but they have certainly declined in the last century, with the result that the chance of seeing any is normally restricted to winter, when migrants arrive in significant quantities. They are also easier to see in winter because ice can force them into the open to hunt – prey killed with the stiletto-like beak can even include such birds as Dunnock (Prunella modularis) in very bad weather.
Developing reedbeds and encouraging the creation rather than destruction of wetlands will, with any luck, assist the species to regain some of its lost territory.
Images © Jeremy Early. All rights reserved.