Hamburg's newly-dubbed Pond of Death

[Guest guest]

Theories abound, but German conservationists struggle to find

convincing explanation for amphibian Armageddon

By Tony Paterson in Hamburg

(Filed: 01/05/2005)

http://www.telegraph.co.uk/news/main.jhtml?

xml=/news/2005/05/01/wtoad01.xml & sSheet=/news/2005/05/01/ixworld.html

On the grassy banks of Hamburg's newly-dubbed Pond of Death, Werner

Smolnik is surveying the aftermath of amphibian Armageddon.

Hundreds of blackened and dismembered corpses litter the ground,

barely recognisable as the bodies of toads.

Mr Smolnik is a senior figure in Hamburg nature protection but was

powerless to prevent - and even now cannot explain - the

extraordinary phenomenon of exploding toads which has plagued this

normally tranquil spot in recent days. It has left scientists and

naturalists baffled.

" I could hardly believe what I saw, " said Mr Smolnik, 55, who was

among the first to witness it.

" Dozens of toads were crawling out of the water. They were puffed up

to almost three times their normal size and making strange

screeching noises. Then they just started popping. Some just

went 'phut!' and their guts spewed out, but others literally

exploded, showering the place with bits of innards. My trousers were

covered in toad entrails. "

Alarm bells began to ring at the city hall, where officials

dispatched an emergency team equipped to clear up chemical accidents

to the scene of the disaster, believing that both toads and pond

must have fallen victim to industrial pollution.

The contents of the pond were pumped into a road tanker and exploded

toads sent to laboratories for examination. The pond was declared

off limits to the public as theories and rumour spread through

Hamburg: was the city in the grip of an epidemic similar to " bird

flu " , in which deadly toad viruses could be transferred to humans?

Last week, some two weeks after the first toad was seen to explode,

German biologists and wildlife conservationists were still uncertain

as to the cause of the carnage. An estimated 1,000 toads died in the

space of a week, but frogs were unaffected.

" All we know for sure is that the toads started exploding right in

the middle of their mating season, which only lasts about a week, "

Mr Smolnik said. " It seems to have occurred just after the creatures

went into the water to spawn, but now that the mating season is

over, it's stopped completely. "

Vets at the city's Environmental Institute for Hygiene carried out

exhaustive tests on the pond water but found no evidence of harmful

bacteria or fungal infections that could have affected the toads.

Anke Himmelreich, one of the vets who conducted the tests, suggested

that they might have been attacked by birds. The skin on all the

corpses they examined bore incision marks, she said, and most of the

amphibians had nothing left in their bodies but the heart.

" We think that birds may have attacked the toads and eaten much of

their entrails, " she said. " It is possible that the toads survived

the attacks and then filled up with water through the incision made

in their bodies. After that they simply burst open. "

A team of biologists in Berlin agreed that every corpse they

examined bore marks indicating pecking.

Their explanation, however, failed to convince Mr Smolnik. " About

1,000 toads were affected in this way, " he said. " If birds were

responsible we would have seen them attacking the toads en masse,

but we saw nothing of the kind. "

He and fellow naturalists believe that the toad explosions were the

result of a foreign virus or fungus that may have entered the pond

via a stream flowing into it which runs through a nearby trotting

race course.

" Several of the race horses are imported from South America and we

suspect that they may have inadvertently infected the pond, " he said.

Late last week, the Pond of Death remained cordoned off, festooned

with " Keep Out " signs. " We are still not one 100 per cent sure of

the cause, " said Heidi Mayerhoefer, who is co-ordinating the toad

investigation for the city authorities.

She said that only one other instance of exploding amphibians had

been recorded in Germany. In the eastern state of Brandenburg, a

smaller outbreak occurred in the early 1990s which was attributed to

hungry birds.

Should the bird theory prove true, it will doubtless heighten

Hamburg residents' anxieties about the feathered creatures. Two

years ago, the city's crows gained notoriety after they mysteriously

attacked joggers, Hitchcock-style, in a Hamburg park without warning.

In the worst incident, about 20 crows " dive-bombed " passers-by,

sending one woman screaming from the park with birds clinging to her

hair, pecking at her face and ears. As with the toads, the cause

remains a mystery.