The sad demise of the butterfly.

[Globalti]

We are told that moths and butterflies are drastically down in numbers because of loss of habitat.

I don't buy it; there are more wild grasslands being established than ever and our former industrial lands are a riot of weeds and wild flowers.

Has anybody considered the numbers of insects that are killed on the roads? Any insect that travels or is blown by the wind is inevitably going to have to cross a road; Britain has the densest road network in Europe and extremely dense traffic - what chance does an insect have of crossing a motorway without being killed? If a butterfly dies, how many fewer butterflies will be born as a consequence? On a hot summer's day, how many dead insects are stuck to your windscreen? With thousands of vehicles an hour, how many insects are being killed in every hour on the roads?

Any thoughts?

 

[skudupnorth]

Seen a shed load today on my ride,nearly took a few out because they seem to like sitting on warm trails !

 

[BenScoobert]

Billions.......I drive a train, during May and June we had to have teams of people to top up washers at every terminal, so about every 40 miles. Swarms of greenfly would mean you needed the wipers on with water almost constantly. Beyond the wipers the fronts of the trains turned from yellow to almost black.

The worst thing I hit was an owl, it was just sat between the rails eating rail-kill, didn't take off unti the last second and flew away from me rather than to the side, I was very disappointed but nothing I could do.

 

[NormanD]

See loads of them each day, but the one thing that was pointed out to me is that we (the mrs too) haven't seen a single wasp this summer ....have they vanished?

 

[Sheffield_Tiger]

See loads of them each day, but the one thing that was pointed out to me is that we (the mrs too) haven't seen a single wasp this summer ....have they vanished?

Nope..

Lost my wasp-sting virginity this year

 

[longers]

With thousands of vehicles an hour, how many insects are being killed in every hour on the roads?

I'm sure I remember a survey a few years ago where people were asked to clean their cars and then record how many dead bugs they collected over a given time but don't remember much more than that.

 

[Slowgrind]

I blame cyclists for much of the decline in insect life!
Just look at a roadies teeth next time your out!!

 

[661-Pete]

Seriously though, the decline in many insect species - butterflies being the most familiar - is almost entirely due to habitat. It may sound callous, but roadkill accounts for a negligible factor in species loss. Most adult butterflies which we see and enjoy flying around the countryside will have already mated, and the females laid their eggs, quite soon after emerging from the chrysalis. So the adults we see fluttering about the bushes will have mostly 'done their bit' to keep the population going. The few that get crushed on our roads are nothing compared to the individuals taken by spiders, birds, reptiles, other insects, etc. etc. It's part of the natural food chain.

It is worrying that once-abundant and still very common species like the Meadow Brown, Gatekeeper and Small Heath are now regarded as under threat, because their favoured habitats - rough grassland and hedgerows - are threatened by intensive agriculture. And the Small Tortoiseshell - once the commonest of the Nymphalidae family - how few of those we see around, these days! I remember back in the drought year 1976, when there were vast clouds of tortoiseshells swarming across all our roads and gardens. Plenty got squashed on the roads, but there were plenty more to make up the numbers. It could be that the very Latin name of the species - Aglais urticae - sheds some light on its decline. "Urtica" is Latin for nettle: this is the main food plant of the caterpillar. Humans - understandably - don't like nettles around, so on goes the weedkiller...

Last year was actually a brilliant year for butterflies: the Painted Lady above all others. This: normally a migrant species that doesn't over-winter in the UK, managed to survive the relatively mild winter of 2008-2009, so there were vast numbers around, throughout UK, during the summer of 2009. Some estimates put it at over a billion. But - last winter was a severe one so none survived over-wintering in the UK. Hence, here in UK this summer, we have to wait for the migrants. I haven't seen any PLs yet in 2010...

 

[skudupnorth]

I blame cyclists for much of the decline in insect life!
Just look at a roadies teeth next time your out!!

LOL !!!!! Had a munch this morning !

 

[Davidc]

we (the mrs too) haven't seen a single wasp this summer ....have they vanished?

We found more than enough on Saturday on the CC Devon ride - see here - post #50 and zoom in on left hand middle finger if you want to cringe!

(One of our number bought a cream tea and they noticed).

 

[theclaud]

I'm with Pete on this. Lots of moths and butterflies are habitat specialists - some even depend on a single food plant for the larvae. Intensive agricultural practices have wrought havoc on butterflies and moths through habitat loss and pesticide and fertilizer use, as has the decline of woodland management and practices such as coppicing. Not to mention the effects of light pollution on night-flying moths. If we're talking specifically about car-related damage, I'd be inclined to worry more about habitat loss from road-building, pollution, and road lighting than about the splat factor.

 

[661-Pete]

... as has the decline of woodland management and practices such as coppicing.

Mrs P and I have tried our hand at both coppicing and hedge-laying - voluntary stuff with a local conservation group. Anyone else tried? It's great fun, I promise you, and you get a real sense of satisfaction with having achieved something. Though hedge-laying is very slow especially if (like me) you're not very skilled at it: I keep on breaking the stems that I'm trying to weave into the new hedge. But it really is doing its bit to re-vitalise our countryside.

Not to mention the effects of light pollution on night-flying moths.

And bats (though I did see a bat fluttering through a brilliantly-lit city-centre car park, a few weeks ago). And barn owls. I fear our local barn owl in the French village is gone for good, haven't heard it these past two years...

 

[e-rider]

Billions.......I drive a train, during May and June we had to have teams of people to top up washers at every terminal, so about every 40 miles. Swarms of greenfly would mean you needed the wipers on with water almost constantly. Beyond the wipers the fronts of the trains turned from yellow to almost black.

The worst thing I hit was an owl, it was just sat between the rails eating rail-kill, didn't take off unti the last second and flew away from me rather than to the side, I was very disappointed but nothing I could do.

lucky you haven't had any suicides then - that must be fairly common on the railways?

 

[Fizzypigeon]

Just about every species is facing declines apart from rats seagulls and pigeons. Cant remember the last time I saw a earwig or a grasshopper. The cause is obvious- a lethal combination of habitat loss and chemicals in the environment and it is unstoppable.