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Send some rain! Think of the baby diptera!

This summer is the dries on record in Finland by quite some margin. Total rainfall in Helsinki (where I live) since May: 15 mm! :o Average would be about ten times more.

I fear this is going to decimate the populations of many diptera, especially those living in moist soil or wet dead trees like the handsome Temnostoma hoverflies. Also many springs and small streams have totally dried up. We'll see how the springwater species like a winter without the 'warm' groundwater for protection. Year 2002 was also very dry and it killed many park trees and whole pine forests on rocky ground. This year will be worse :(

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Perhaps this could be relationed with global warming (not just caused by human being, perhaps we could be pass a normal rise of temperature in climatological history...)? Here in POrtugal, each year, the temperatures seems rise a little more. Yes, I note that the temperature is getting more hotter as time goes on... :(
15 mm until now... is very few, indeed... I know in UK the weather got a little more hotter than usual a few weeks ago... Imagine if the panorama keeps the same... :| And what about your crops??

I read somewhere that in about 2020 ALENTEJO (in South of Portugal, to North of famous Algarve) could turns a real desert... and we can have the first signals of paludism!! :| Perhaps it is not a so crazy prevision...

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Hi Kahis
Sorry to hear that your drought is continuing. We had very long dry period earlier this summer, but now we are getting heavy rain. However the groundwater is still very low and many ponds have dried up, so there may be problems for some species. Fortunately some, like the stratiomyids, can survive dry periods. The global change in the climate will affect many insects, and in Britain I think a few will benefit from the warmer weather, but many others will be lost, particularly as small remnants of habitat are destroyed and not replaced elsewhere.
They are interesting times, but quite depressing. :(

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It's rather dry in Sweden as well ... Could the dry weather be of any benefit to certain kinds of diptera?

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I'm not sure. I will try to do just a guess:
I think the same flies that survive in deserts... Culicidae?? Stratiomyidae...
Really, like you, I want to know what dipters can survive a lot of time with very tiny quantities of water! - it is your question. ;) But those flies I suspect that can benefit of more drier weather...

I know for example, that salticid spiders, (some) has great capacity to survive in very dry conditions. One example really true: I forgot one salticid inside a car - Philaeus chrysops (very beautiful indeed) - that survived during more 4 hours with almost 70?C inside! Very impressive! There are much more salticids with spectacular records concerning live with very, very small quantity of water and very dry habitats.
Of course, there are deserts that aren?t dry. :P Like Antarctica.
Look... another question arise! Which kind of dipters we can find in Antarctica?

Another example (but in extreme opposite).... the famous Araneus diadematus can survive(if temperature decrease slowly) until -30 ?C! Life is more fantastic that we usually think! ;)

Sorry, if I talk about "no dipters"... but everything is in relation! There are many spiders that consume dipters, and some dipters that parasite spiders. ;)


Below follows an image of Philaeus chrysops to get an idea:

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What can I say?
1. I understand you.
2. In this case I try to tell myself: you can't change it, than take it, take it and regard as unic possibility to observe, there were a lot dry years in Finland before, but this one will be observed at least.
Nikita

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This is a gloomy subject, isn't it:( I grew up on a farm in Australia, where my father, strongly influenced by the organic and biodynamic movement and an active conservationist from his teenage years, believed that if you took care of the soil, everything else would follow. In those days, I think he was right, but on moving to the UK, I realised that I now had to add to the list and taking care of the invertebrates was crucial. It seems that within my lifetime the list of what is absolutely basic and cannot cope with the pressures of ever increasing human presence and activity inexorably grows and now we must actively manage for water supply in an integrated way. These things cannot just be done in isolated pockets by individuals in their gardens and wardens on nature reserves that are too small for long term sustainability anyway. But this is what we have to start with and we have to hope that by providing that personal example and committment that slowly slowly wider attitudes will change. My feeling is that this is happening, but almost certainly too slowly. Perhaps the very best thing we can do is try to communicate our sense of privilege at the glimpses we get of these beautiful creatures and the thrill each little piece of knowledge gained about their lives gives and leave it at that. (Of course you have to be able to do that without establishing a reputation for being the local weirdo, which can be quite tricky, especially if you are seen regularly with a pooter:D)

If it wasn't raining here :p I think I'd spend an idle half hour in the garden just peering at stuff now, to cheer myself up. As it is, I'll have to content myself with going into the kitchen and making pizza dough - all that kneading - v theraputic.B)

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It certainly can benefit some species. We are seeing many southern species arriving to Finland. I guess you get some of that if Sweden too.

Unfortunately Finland has lost most of the dry, open spaces best suited for xerothermic species through changes in agriculture and very (perhaps too :|) effective handling of forest fires. For example many asilid species are now apparently extinct in Finland and most of the other have lost ground.

Species that love warmth and young(ish) forests thrive in Finland right now. The first time I saw Limenitis populi, a butterfly that rivals many tropical 'exotics' in beauty was heart-stopping. My butterfly guide listed is as south-eastern rarity (as it was in the seventies) and I had no clue about its rapid expansion westwards during the nineties.

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Maybe this wil help;

http://home.wanadoo.nl/robhee/22-7-2006%20Amsterdam.mp3

raining regards, robert B)