News for September 2000, Spoonbill Success
Bird On! News
1st September 2000
LAST month I noted the excitement generated by the breeding attempt by a pair of spoonbills on the RSPB's Mersehead reserve on the Solway in south-west Scotland. Following this announcement the Rare Birds Breeding Panel has revealed that spoonbills reared two young at a secret site in East England in 1998. The same pair bred again successfully last year but the RBBP has yet to confirm whether the birds bred again this year.
This is the first confirmed nesting by spoonbills in Britain for 330 years, so is a cause for celebration. The return of the spoonbill has long been predicted but has taken a long time to happen. At the same time spoonbills have started nesting in England they have also started to colonise northern France, with five pairs breeding this year in the thriving heronry at Marquenterre on the estuary of the Somme. Birds from the thriving Dutch population are responsible for this range expansion. This, in turn, is due to the spoonbills enjoying much greater protection on their annual migration to and from West Africa.
There is now a chain of wetland reserves on the Atlantic coasts of France and northern Spain where the migrating spoonbills can rest and feed safely, and this has made a tremendous difference to survival rates. The Dutch colonies are now close to capacity so it is only to be expected that new nesting colonies will become established.
Thriving little egretsHowever, it seems unlikely that the growing spoonbill population will ever match that of the little egret. Until a couple of decades ago this elegant bird was a great rarity in Britain but during the 90s egrets became an increasingly familiar sight on the estuaries of southern England. It wasn't until 1996 that the first confirmed nesting in Britain took place with one pair on Brownsea Island in Poole Harbour. This past summer little egrets have nested successfully at several English sites though it has yet to be revealed quite how many birds nested where. My guess is that, before long, several hundred pairs will be nesting annually in Britain.
It is easy to plot the northward expansion of the little egret as the birds moved north through France in the early 80s, first colonising the Loire, then moving on to Brittany and then the Somme. The heronry at Marquenterre now has a thriving population of little egrets nesting among the grey herons and in recent years they have been joined by two other species: cattle egret and night heron.
Cattle egret nextIn Europe, Southern Spain was once the cattle egret's stronghold. The first signs of a northward expansion were noted in 1961 when they started breeding in the Ebro delta. In 1968 two pairs nested in the Camargue and by 1975 that colony had grown to 125 pairs. Slowly but surely the pioneers moved north, reaching the Brenne (in central France) and the Dombes (to the north of Lyon) in 1992 and the Somme in 1995. England has to be the next step.
Cattle egrets like to feed with cattle but they are also great scavengers and particularly fond of rubbish tips. This adaptability explains their success. Though originally birds of the tropics, they have the ability to cope with cool, temperate weather as their success in New Zealand (colonised in 1963) and Canada has shown.
With the little egret already nesting in England and the cattle egret looking increasingly likely to follow suit, it is no surprise to discover that the night heron may be joining them. Because of its crepuscular habits this is a bird that is more easily overlooked. However, it is steadily increasing and expanding its range in southern Germany, Lower Austria, France and Spain, and has become a more regular visitor to southern England. In the Americas night herons nest as far south as Tierra del Fuego and the Falkland Islands so there is no reason why they should not be able to cope with the British climate.
Waiting for a great whiteThe final heron to complete the set is the great white egret. Despite its abundance in the Americas, much of Africa and south-east Asia, the great white has always been a rare bird in Europe. Fifty years ago it held just a tentative toe-hold in Austria (Neusiedlersee) and the Balkans. However, there has been a notable increase in numbers in the last 20 years and records have become far more frequent in western Europe. A summering bird appeared in Holland in 1976 and two years later the first pair nested. Several pairs now nest annually at Oostvaardersplassen, Flevoland.
Steadily increasing numbers have been appearing in northern France in recent years. Since 1982 I have been an annual winter visitor to what the French call Les Grands Lacs de Champagne Humide. These are extensive, man-made lakes created to take floodwaters from the rivers Marne and Seine to prevent flooding in Paris. They provide superb wildlife habitat and attract large numbers of birds. In November 1993 I saw great white egrets here for the first time - a flock of six. Now they are regular winter visitors to the lakes with flocks of as many as 20 birds a common sight.
Great white egrets are becoming increasingly frequent visitors to Marquenterre. Several of the birds visiting the reserve have been ringed and by reading the rings with a telescope it has been possible to discover their origin. They had been ringed as nestlings in Italy's Po Delta. Until recently Italy was best known for shooting rather than conserving birds but attitudes are changing fast. Birdwatching is becoming increasingly popular, while it was the establishment of the Regional Park of the Po Delta in 1988 that has safeguarded this large and important wetland. All 10 species of Europe's herons now breed in the Park.
Though the great white remains a rare bird in the UK, it is a regular summer visitor in increasing numbers, while autumn and winter birds are also appearing. It looks set to nest here before much longer.
Save the AlbatrossThe annual British Birdwatching Fair, held at Rutland Water in August, has become one of the major events of the birdwatching year. This year's Fair was bigger than ever and it was interesting to see both the Po Delta Regional Park and Marquenterre Nature Reserve taking stands and hoping to attract more human visitors. Every year the Fair raises money for an important conservation cause: this year's theme was BirdLife International's Save the Albatross campaign which is targeted at the huge annual slaughter of seabirds by the long-line fishing industry.
In recent years long-line fisheries have become the accepted method of catching tuna. These avoid the accidental drowning of dolphins and ensure that cans of tuna can be sold claiming that the fish were caught "in a manner that minimises the risk to marine mammals". The dolphins may be safe but sadly the same cannot be said for marine birds as many thousands of albatrosses, petrels and shearwaters are killed annually by the fishery. One tuna longline may be 100km long and catch as many 50 seabirds on a single line. Reliable estimates indicate that in the three most recent seasons a fishery operating off Chile has killed over 100,000 albatrosses and petrels.
Albatrosses are among the longest-lived of all birds: they can live for up to 50 years but their slow rate of reproduction means that they are unable to withstand this level of mortality. Many populations have crashed as a result. BirdLife's Save the Albatross campaign is urging fisheries to avoid the slaughter by weighting their lines, setting them at night, and using plastic coloured streamers to scare off seabirds. More details about the campaign can be found at www.uct.za/depts/stats/adu/seabirds.
Keep up the crow cullLastly, I cannot resist rising to the bait of a letter published in the September issue of the magazine Bird Watching. The writer of the letter, Ian Marr, complains about the RSPB's policy of culling foxes and crows on its Abernethy Forest reserve in Scotland. The RSPB is controlling these predators in a bid to halt the decline of the giant forest grouse, the capercaillie, but Mr Marr believes that "the RSPB is trying to put evolution in reverse by encouraging less successful, less adaptable species at the expense of more adaptable ones". He believes the RSPB should leave the foxes, crows and capercaillies alone to find their own equilibrium.
There is little doubt that if such a misguided and sentimental policy was followed the capercaillie would soon be lost from Abernethy. One wonders whether Mr Marr is aware of the fact that since taking over Abernethy the RSPB has culled many hundreds of red deer in a bid to help the Caledonian pine forest regenerate. Without active management (which includes killing certain species) Abernethy's biological diversity would soon be diminished disastrously.
We live in a landscape radically altered by the hand of man over many centuries. If we do not look after our surviving flora and fauna with care we are likely to lose all the more vulnerable species of which the capercaillie is a classic example. Fox and crow control is a small price to pay for retaining such magnificent birds as the capercaillie. I can see foxes and crows in my own garden any day but when I next visit Abernethy, I would far rather see a capercaillie, not yet more foxes and crows.