The bird has survived centuries of fear and loathing. But it's only now, when it attracts reverence and awe, that it is in trouble. It survived our hate; perhaps our love will finish it off. A dog-walk taken as the light began to fade and the only bright thing in sight was white and in flight.

Barn owl, of course; the signature bird of this part of Suffolk. It has a long history as a bird of ill omen, but it tells me that I'm home and that all's right with the world. There he was in plain sight, a bird I know from the briefest glimpse. White wings - but that uncertain, arrhythmic bobbing and fluttering flight tells you instantly that this not a black-headed gull.

The path follows the coarse margins of the field and the areas of rough grassland that barn owls love best, crossing and recrossing in pursuit of short-tailed field voles. They do so in a silent and graceful frenzy because their hunting window is very narrow and full darkness brings an end to it. They are creatures of the half-light.

The silence comes from the built-in mufflers on their wings, a device that dismays the creatures beneath. As the light faded, the owl ignored me and sought to eat his fill, remaining in sight for about half an hour.

His eyesight keen/scans round the green,/the owl is out to kill. A poem I wrote when I was 10, which rightfully failed to win the prize. It was a spooky poem, of course, but then owls have been forced for years to carry the people's fear of the powers of darkness. They were often killed to ward off various kinds of evil. But we of the 21st century have risen above such things.

These days we just kill them by spoiling our countryside. Changed farming methods - less rough grassland to hunt over, fewer old buildings to nest in - have caused a terrible drop in barn owl numbers.

But the Suffolk Wildlife Trust has had a spectacular response to its barn owl box programme. More than 800 boxes have been erected, and barn owls have taken to a third of them. As a result, they are a much more frequent sight.

The owl paused for a moment and perched, marvellously disappearing as it did so, for its mantle is not white but pale brown. After a while, it rematerialised - everything barn owls do is vaguely spooky - and took wing again.

Colossal facts about squid

I reckon I know a thing or two about wildlife. That makes it all the more wonderful to trip over my own ignorance; the wild world is so much vaster than any human mind, even mine. I caught a few moments of a quiz show and there was a question about the colossal squid.

Now that had to be wrong. I know about giant squids, the mysterious creatures of the depths, creatures that can't be watched because they live too deep, and can't be captured because they fall apart. But colossal - was this a jest? It was not. The colossal squid is a genuine species. It has been known since 1925, when it was described from a pair of arms. A mere half-dozen specimens have turned up since.

They are not much longer than a giant squid, up to 14m or 46ft. But they are much more solid, chunkier things entirely. They have hooks on their tentacles for grasping their prey (big fish) and they leave many a scar on their own predators, sperm whales like Moby-Dick. They live in the Southern Ocean, a couple of thousand metres down.

How many more creatures are there out there that I don't know about? Getting on for a million at the lowest count. How many more things that nobody knows about? Some say up to 50 million.

In the wild world knowledge is glorious, but the colossal ignorance of even the most learned people is a constant inspiration to me - and, for that matter, to them.

Biodiversity for grown-ups

The destruction of wildlife continues across the country and the planet because there is a curious assumption in high places that it doesn't really matter. It is thought to be something that is of concern only to the children, the childlike and the cranks. This week Mark Avery, conservation director of the Royal Society for the Protection of Birds, provided a welcome corrective to this attitude.

After the Environmental Audit Committee found - surprise surprise - that the Government is not doing enough to protect threatened wildlife, he commented: “Biodiversity loss is as big an issue as climate change.” Absolutely. Biodiversity is not only numbers, nor is it only the wouldja-believe-it page in a children's comic. It is the method by which the planet works.

There are 941 species and 56 habitats on the priority list for conservation in England alone. This should be a matter of commitment and investment. Instead, it is always a question of how little we can get away with. Who stops to consider that the loss of biodiversity is ultimately destructive for human beings? Progress is always the thing; progress towards our own destruction.

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