Adrift on a boat, with a wall of freshly leafed willows passing steadily on each side, I could not help thinking of Ratty and Mole's adventures on the river in "The Wind in the Willows." There were fresh mole hills to be found on the banks, and here and there holes in the riverbanks that might just have been those of Ratty's relatives the water voles. The otter spraints on exposed tree roots, and the flurry of wings overhead, the to and fro of hordes of great and pygmy cormorants, were real, however, not imaginary.

This was the delta of the Danube, not the quiet river of that famous children's tale. I was here in search of otters, native European mink, spoonbills and pelicans.

The various channels of the delta serve as highways and byways for boat traffic from across Europe heading down the Danube from its source in Germany to the Black Sea. Great barges carry goods between nations, while solid wooden row boats, too heavy for me to move, are rowed by immensely powerful locals. It would be as much as I could manage to steer such a boat even running with the current, but they row stoically up-river with muscles of steel.

Their rowing is accompanied by reed-bed birds, warblers and buntings, for the delta is not just channels for water traffic: It is also one of the largest commercial reed-beds in the world. Tall reeds sway on either side of almost every channel, hiding from sight the small ways that lead in to the marshes, to the pools where the birds breed.

I was lucky. I had neither to row, nor to put up with the constant passage of the barges. I was on board a specially equipped vessel, high enough to look out over the reed beds, and large enough to sleep several people comfortably, yet still small enough to access the remoter areas of the delta. In that comfortable way, I made several journeys around the delta to seek and film the wildlife there.

At first, the excitement of being within lens range of nesting glossy ibis and white spoonbills was enough to overcome the discomfort of standing thigh-deep in cool water, but when I realized that the willow leaves adrift in the water were wriggling toward me, and that they were actually the largest leeches I had ever seen, I decided to stay in the boat.

Occasional sightings of rare migrant spoonbills here in Japan sometimes remind me of those exciting weeks in the delta, but nothing can beat being in range to hear them clatter their ladlelike mandibles at each other in their nests.

The ibises were more guttural in their communication, their displays less demonstrative than the spoonbills', but they were beautiful to watch, especially when the sun glinted on their bronze-sheened plumage.

That mixed colony of spoonbills and ibises was a fabulous sight, but something even more interesting beckoned. It required a forced passage through an especially dense reed-bed, the reeds more than an oar's length tall. We would never have made it had we not had a ranger in charge of us who was every bit as strong a rower as any Danube boatmen.

There, in the farthest, remotest section of the Danube Delta Biosphere Reserve, is a colony of particularly splendid birds: the Dalmatian pelicans. It was these that we battled our way toward through the reeds.

There is something grotesquely prehistoric about most pelican chicks. With their black, leathery hides and their huge distorted beaks with the floppy pouches, white pelican chicks look for all the world like enormous, horribly overweight, misshapen bats.

In contrast, their close cousin the delicately shaded Dalmatian pelican, a rarer species in the delta, rears chicks that are almost cute, covered in a layer of fine white down. The adult Dalmatian pelicans at their nests display a curious head wagging, in which they hold out their bills with their pouches stretched taut just like a long triangular flag.

The Danube is a river with a political position. It flows through about half the countries in Europe, with each country's additions to or subtractions from the river affecting those that receive it farther down.

Now in early May the pelicans will be in their colony, quite unaware of the impact that a war may soon have on their life-giving delta. The endless battling in Yugoslavia and the political struggle between Serbs and Kosovars that is driving waves of refugees into neighboring countries makes the news headlines day after day. Long after the immediate human conflict is resolved, though, the ecological effects will remain to haunt the human and wildlife residents of neighboring countries. The cost of war includes not just human suffering, but also immense environmental suffering too.

The World Wildlife Fund has already put out a press release voicing its concerns over an environmental crisis looming over the river downstream of the political and human crisis. Most particularly at risk are the environments of the delta of the Danube in Romania, and of course the Black Sea into which the river empties its contents.

The greatest concern for countries such as Bulgaria and Romania, into which the river flows from Yugoslavia, is the likelihood of oil slicks. They urgently require equipment to capture and deal with the slicks.

They also need monitoring equipment to assess the more insidious invisible impact of the war. No one yet knows exactly what is included in the range of unidentified chemical pollutants that has been discharged into the Danube. Whatever they are, toxic materials are reaching the fishing grounds of people and wildlife alike as they flow through the delta and into the Black Sea.

The lower Danube River and its delta comprise an area of tremendous environmental importance, but even apart from that, about 10 million people rely on the river for drinking water.

"The humanitarian issues are first and foremost in our minds, as they are for everyone else," observes WWF's Danube-Carpathian program director Philip Weller. "However, only immediate measures to stop the downstream flow of pollution will prevent an ecological catastrophe from following the humanitarian one.

"WWF is concerned that long-term damage to the environment in both Yugoslavia and surrounding Balkan countries will only increase problems in the region."

We must all hope that for the sake of the suffering, for the sake of the neighboring countries, and for the sake of the environment in all countries astride the Danube downstream of the conflict, that the aggressors in Yugoslavia will soon come to their senses.