News for November/December 2001
Bird On! News
21st November 2001
Bird News - autumn 2001
Much has been written about the impact of foot and mouth disease on Britain's farming industry, and its knock-on affect on tourism. Less has been said about its impact on wildlife conservation, considerable though it has been. One of the areas worst affected by the disease was Dumfriesshire, on the Scottish borders, and it is here that the entire Svalbard (Spitzbergen) population of barnacle geese winters.
This autumn the first returning barnacles, a flock of 500, arrived on the Wildfowl and Wetlands Trust reserve at Caerlaverock on September 23. Numbers built up quickly, and 15,000 were present by the end of the second week of October, rising to over 20,000 by the end of the month. Checks of the proportion of young birds to old have revealed that the barnacles have had a very poor breeding season, with just 1% of young in the flock. Disastrous seasons such as this are quite common for arctic-nesting geese, and are usually the result of severe weather early in the nesting cycle. This poor breeding season means that overall wintering numbers will be lower than last winter's peak count of nearly 24,000. The latter, incidentally, represents an astonishing recovery from the 400 or so birds this population had plummeted to after the Second World War.
A smaller wintering flock is no bad thing, for the merses (grazing marshes) where the geese feed have not been grazed by livestock this past summer for the first time in living memory, due to foot and mouth. The barnacles depend on the sheep and cattle grazed merses for much of their winter fodder. If the grass is too rank or long they are unable to graze.
With no livestock to do the grass cutting, staff at the WWT's Caerlaverock refuge worked hard during the summer cutting the fields on the reserve for silage and hay, but this was not an option on the merse. How much this lack of grazing will affect the geese remains to be seen, but WWT staff are optimistic that the barnacles will find sufficient grass to sustain them until they return to the arctic next spring.
One theory expressed last spring was that that these geese helped spread foot and mouth, and there were forecasts that outbreaks of the disease were likely in Norway, where the Svalbard barnacles rest on their migrations north and south. No such outbreaks did occur, and it seems highly unlikely that geese are capable of spreading this disease.
Another impact of foot and mouth is an absence of information on the breeding success of both our common and rare breeding birds. We usually know at this time, for example, how many young the English, Welsh and Scottish red kites have reared between them, but no such figures are available. Nor are there any figures for ospreys available, but we do know that both pairs of ospreys that nested in England (one in the Lake District, the other on Rutland Water) successfully fledged young.
While the Rutland nesting was thanks to an ambitious reintroduction project, the Lake District ospreys were natural colonisers, spilling over from the burgeoning population in Scotland. The pair nested on Lake Bassenthwaite, where they provided an extremely popular attraction for visitors all summer. Their popularity was enhanced by the foot and mouth restrictions which stopped tourists from visiting many areas in the Lakes, and no fewer than 25,000 people went to see them at the special osprey viewing point, established by the Forestry Commission, the National Park Authority and the RSPB.
Ospreys are very much birds of tradition, and there seems every chance that the same birds will return to Bassenthwaite next season. Details of where to find the watchpoint, and a diary of their 2001 breeding season, can be found at www.ospreywatch.co.uk.
Ospreys may be comparatively rare in the UK, but they are a widespread and successful species worldwide. Like the osprey, roseate terns are also very widely distributed, and can be found from the West Indies to Australia. However, nowhere is this attractive bird common, and it is particularly scare in the British Isles, with just a few scattered colonies. One of the largest is on Coquet Island, off the Northumberland coast, and here the internationally important population had one of its best breeding seasons ever in 2001, with 42 pairs rearing at least 55 young.
Coquet Island is an RSPB reserve, though it is not open to visitors. The reason behind the terns having such a good nesting season was, apparently, the provision of special nest boxes designed to protect the terns' nest, eggs and chicks from both weather and predators. No fewer than 40 nest boxes were occupied.
There used to be a flourishing roseate tern colony in the nearby Farne Isles, but this has dwindled from almost 100 pairs in 1953 to just a single pair this year. The latter did nest successfully, fledging a single chick. However, there seems no good reason why nest boxes shouldn't be provided in the Farnes, too, in a bid to help the birds.
While roseate tern population dwindle, those of another seabird, the cormorant, are thriving. Every year new inland breeding colonies are being established, much to the dismay of fishermen, who loathe this bird like no other. Quite how much damage cormorants can inflict on inland fisheries has never been proven, but the birds do have voracious appetites.
Cormorants have full protection under the current law, and anyone who wants to shoot one to protect a fishery has to get a licence to do so. The latest issue of the RSPB's magazine, Birds, reports the successful prosecution of Terence Day, a member of Letchworth Angling Club, for killing two cormorants and trying to kill another. He was fined £250, had his shotgun confiscated, and his shotgun certificate revoked.
Prosecutions such as this will do nothing to help the uneasy relationship between fishermen and bird protectionists. Since Britain's cormorants gained legal protection, their population has increased dramatically, and there is a strong case now for partly removing or suspending the protection, which hardly seems needed for such a successful species. There is no doubt that the RSPB would gain a lot of respect in many quarters if it acknowledged that cormorants are really in no great need of protection any more, but such a move seems highly unlikely.
Cormorants do have the disadvantage of being one of the most unattractive of birds, and there are few birdwatchers that are enthusiastic about them. Not so another fish-eating species, the little egret. Until a decade or so ago, this elegant small heron was a real rarity in Britain, but then increasing numbers started appearing in southern Britain, culminating in the first recorded breeding here (in Dorset) in 1996. Again, due to foot and mouth, there are no published figures indicating how many pairs nested here this past summer, but it seems likely that a good number did so. Increasingly large flocks are being recorded at many sites (Chichester Harbour is one of the best places to see this species in numbers), but few can rival the WWT's reserve at Llaneli, in south Wales, where no fewer than 217 were counted roosting in early September, a 300% increase over the 2000 peak count. Special tours have been laid on at the reserve to see the egrets, while it is apparently impossible not to see egrets on a visit to the centre at any time.
Little egrets have colonised the UK naturally, but this cannot be said for a number of other new colonists. The November issue of the monthly journal British Birds looks at no fewer than 22 species of non-native birds nesting in the UK in 1999. Several of the so-called non-natives are birds that do occur here naturally, but don't normally nest in the UK, This includes such species as whooper swan and barnacle goose. The situation with whooper swan is complicated, as four apparently wild pairs nested in Scotland and Northern Ireland, while birds that had escaped from captivity nested in Berkshire, Hertfordshire, and on Loch Slochy in Ayrshire.
Other less likely non-natives nesting in the UK include peafowl, eagle owl (one pair bred in the north of England for the fourth year running) and no fewer than three species of parakeets - rose-ringed (or ring-necked), Alexandrine and monk. Pairs of rose-ringed were reported from four counties, with the biggest numbers (up to 15 pairs) in Surrey. However, there are clearly many pairs going unrecorded, for a roost at Esher in Surrey regularly records up to 3,000 individuals, a spectacular and very noisy sight.
So far these parakeets do not seem to have had too much impact on our native wildlife, though it is known that take over nest holes from woodpeckers. However, there is a far more serious invader lurking across the North Sea in Holland that has yet to reach our shores. This is the Indian house crow, one of the most successful birds in the world. A letter in the same issue of British Birds from Dr Colin Rydall warns that wherever this species has become established (so far 20 countries outside its native range) it has become "a predator of native bird species, a crop-raider, a potential public-health risk, and a general nuisance. As a consequence, control/eradication programmes have been or are being initiated in many areas. A sobering fact is that, to my knowledge, only one of these campaigns can really be considered to have been successful."
A small population has become established in the Netherlands, and Dr Rydall warns that if numbers expand "nothing will be done until it is too late to take any effective action without great difficulty". One has to hope that the Dutch authorities take note, and destroy these crows before they start to spread. While little egrets are a delightful addition to our fauna, we are better off without the unpleasant and invasive house crow.