Saturday 15 August 2020

Dead birds and Occam's Razor

How many times have you seen a dead bird in your life? In suburban London, never. Not that I can remember - not in childhood, not in West Ealing, not in Perivale. In Jeziorki, on Warsaw's edge - a few. Big ones, herons, as well as crows. But rarely - once every few years. But in Jakubowizna, seeing dead birds by the roadside is a regular occurrence. Two in my działka this summer alone, three spotted on a walk along ulica Wspólna from Jakubowizna to Chynów and back in one day.

Dead thrush, ul. Wspólna, Chynów

What's happening? Well, 5G roll-out in Chynów started last month (at least that's the first time my laptop's wifi dashboard gave me a 5G option for internet access), but dead birds have been a feature of life in Jakubowizna since buying the place. And I don't go for 5G conspiracy theories.

Dead chaffinch, ul. Wspólna, Chynów

So what's causing birds to die around here in noticeably high numbers?

Dead kingfisher, Jakubowizna

I can only surmise that it's the result of the pesticides used by farmers tending their orchards. Either poisoned worms get into the birds' food chain or the birds, pecking at the cherries, plums and apples get poisoned directly. 

I've lived right next door to agriculture for the best part of a third of my life, and I'm aware of the cycle of ploughing, sowing, and reaping - and the spraying of crops in between. But the field next door in Jeziorki is arable land - oats, barley, wheat, rapeseed. Birds are not as interested in grain as they are in large acreages of ripening fruit. [I must point out that some years ago, we had blackcurrants in our garden, just across the fence from the barley field. It was sprayed, the children ate the blackcurrants, both were sick.]

In Jakubowizna, the sound of early summer is the retort of compressed-air bird-scarers, going off at random intervals on the cherry orchards and strawberry plantations. At first you think it's a shotgun (as in the English country sound of a distant farmer shouting "GET ORFF MAY LAIRND!" followed by a BANG!) After a while, you get used to it, and the sight of the sky filling with a circling swarm of starlings. But the cherry season is over. The sound you hear in these parts now is that of tractors at nightfall - tractors pulling spraying equipment that from a distance look like they're laying down fog. These are chemicals going down onto apple trees. 

You can tell instantly which orchards are sprayed - the apples in them are (almost) flawless. No tell-tale holes giving away the fact that a lodger or three lurks within. My apples - unsprayed - are full of insect life and nibbled at by birds. Not a single apple on my little orchard is without blemish. [This is the type of apple scrumpy is made from in the West Country of England. My apples are de facto organic. No papers, no certificates, just fruit that's never been sprayed.] 

Apples are divided into two sorts - jabłko deserowe (table apples in English), that are blemish-free and sell for top złotys in the supermarkets, and jabłko przemysłowe ('industrial apple'). The latter ends up in juices, sauces, cakes and yoghurts; it is processed and pasteurised. There's no point investing in pesticides - just collect it by the tonne and get a few grosze per kilo for it. Any worms inside will be heat-treated and the bacteria from their faeces duly killed off. The more so if the apple juice starts to ferment.

I don't know whether the pesticide affects the birds directly or indirectly, but I'm sure it gets into their guts and does something to their nervous systems.

Earlier this year, I noticed several lapwings around ulica Miodowa by the railway line. My guess is that lapwing colonies have been displaced by the roadworks associated with the S7 extension to the north-west of here and have flown south seeking quieter haunts. It was good to see them over Chynów! However, I've been back there many times since, and have never seen them again. Maybe the land around here is too polluted by intensive agriculture - I don't know. I do know that 5G isn't to blame - it's only just been activated, and the dead birds have been around a while.

Occam's Razor suggest to look for the most obvious solution. Since noticing dead birds as a regular occurrence, I've started washing all the fruit I eat, including citruses. Raspberries are the only exception. Apples - we're told the peel is good as it contains roughage - I wonder how much pesticide is soaked up in the skin. 

The main anti-parasitic and anti-fungal agent used is Thiabendazole. Could this be the culprit?
I checked - the EU allows 4 milligrams of residue of Thiabendazole per kilo of apple. That's for humans. For birds though?  Reading this article in the Journal of Agricultural and Food Chemistry, the best way of decontaminating apples is to soak them in a solution of ordinary baking soda (sodium bicarbonate) for 12 to 15 minutes. That or peeling the fruit. Scary!

I've also decided to leave a significant part of my land as meadow, with wildflowers dominating, so that the bees can forage for pollen.

This time last year:
My summer space

2 comments:

Jacek Koba said...

Bird life patterns are complex at the best of times, let alone now when so many factors can be thought to be contributing to their behavior. My observation shows that some species are down (skylarks, sparrows, partridge), some have clung on to shrinking habitats (heron, stork, swallows), and some are thriving (bloody magpie!). My train journey today traced an arc from Kraśnik to Warsaw via Łuków (shame I missed you on your tour of Roztocze) and I saw flocks of several dozen storks and swans making plans for winter. I have been known on occasion to dispatch a particularly pesky specimen with an air rifle and hang it up by its feet as a lesson to its comrades – farmers’ ways! Yet, this year, with crops ravaged by disease, birds of all feather have not disappointed. I have never before seen a falcon dining on my lawn after a spectacular midair capture at eye level about 6 meters away from me. He was not bothered by my presence at all.

Michael Dembinski said...

@Jacek Koba

You are right about how different species adapt. In Jeziorki there's been a veritable renaissance of the sparrow. Starlings and magpies always do well. Waterfowl have had a tough year this year - there were no cygnets from Jeziorki's resident swan pair (age? drought?), and the grebes didn't stay.

Falcons I haven't seen - only harriers.