Horse Chestnut leaves damanged by leaf miners

Dear Readers, I’ve written before about the leaf mining insects and cankers that affect horse chestnut trees every year, and about my hope that at some point, creatures will recognise the brown patches in the leaves as a possible food source. The patches are caused by tiny caterpillars that are eating the juicy parts of the leaf between the protective layers of the epidermis.

So imagine my joy during a trip to Darlands Nature Reserve in Totteridge earlier this week, to see a flock of tits working their way through the leaves of just such a horse chestnut. At this time of year, young tits of various species join up to forage for food – it’s always worth checking these out as you might spot a goldcrest or even a firecrest amongst them. The leaves are in a really bad state….

but look!

I’m pretty sure that this blue tit, at least, is getting stuck in. Let’s hope that they teach all their little friends. The most valuable thing would be if they targeted the spots in the spring, before they really take hold, but presumably that will take a few more generations.

Blue tits and great tits are really opportunistic, adaptable little birds – the more mature amongst us (ahem) might remember the birds pecking through the foil and drinking the cream from the top of the milk, back in the days when it was delivered by milkmen. The habit spread so quickly that by the 1950s blue tits all over the country were robbing cream from milk bottles. Interestingly, robins also learned to do this, but the habit didn’t spread throughout the population in the same way, maybe because robins are more solitary birds for most of the year, and the youngsters don’t gather in mixed flocks like the tit species do.

Blue tits have also been spotted drinking nectar from crown imperial flowers, pollinating them in the attempt (as far as I know, the only example of bird pollination in the UK, but let me know if you know of others).

Photo by Mark Williams at https://kensingtongardensandhydeparkbirds.blogspot.com/2020/08/it-was-another-hot-day-but-spell-is.html

Given time, I’m sure that the natural world will always find a balancing point. The problem is the speed of change. Let’s hope that, in. this case at least, the predators are starting to discover a new food source.