Nature Notes

Jenny Dixon

Wharfedale Naturalists Society

wharfedale-nats.org.uk

I’VE just bought some new fat balls for my garden birds and they’re obviously delicious. Suddenly a flock of blue and long tailed tits are frequent visitors, young blackbirds and robins are learning first to jump-and-peck and then to cling onto the holder as it bucks and sways, and corvids, two slightly tousled young magpies and a jay (dandy-fine in his post-moult plumage), are getting in on the act. Not just birds. Two adolescent squirrels, scrawny and always hungry, now regard the treats as specially meant for them.

As you can imagine, this leads to competition and a certain amount of aggression. It’s a good opportunity to study the (often literal) pecking order. Among smaller birds this generally relates to relative size: great tits, blue tits, coal tits - for example. Sometimes sheer determination (robins) or refusal to be moved (gold finches) can pay off, and body language is very important. Last week the dispute started with a squirrel and two magpies and, despite superiority of numbers, the magpies yielded possession. Then the jay appeared. Though really no larger than the others, he was the outright winner. First he lowered his head and stretched out his neck, rather like an intimidating gander, then drew himself up to look as big as possible. His adversaries retreated, then fled.

This led me to reflect on aggression in animals and birds. In a world without health care it’s obviously vital not to get injured. Even a few missing feathers impair speed and agility in flight, and anything more can be fatal. This is as true of predators as of prey species. As a result most creatures have evolved other ways of demonstrating and recognising relative strengths and thereby weighing up the odds and settling disputes. Even rutting stags carefully size up the opposition from a distance and then by parallel walking, before committing to the danger of a fight.

Nearer to home, I’ve found great interest in watching the interactions of my garden hedgehogs. Generally hedgehogs are tolerant creatures, feeding together on the lawn peacefully. However, sometimes confrontations occur: whether these are territorial or related to mating is not clear. When I observed this happening, the two opponents engaged in a shoving contest, a trial of strength where one – often the smaller and usually a male – sideways swipes and heaves his opponent off the lawn and into the flowerbed. The defeated animal, unhurt, then scuttles away. Would that human disputes could be settled by a bit of gentle wrestling!