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hi on unday it was sunny very mild
about pluss 2 there was a lot of the flys we have see this before.
cheers and brrrrrrrrrrrrrrrrrrrrrrrrrrrrrr
----- Original Message -----
From: "Stephen Shaw" <srshaw@dal.ca>
To: <naturens@chebucto.ns.ca>
Sent: Tuesday, February 20, 2007 11:32 PM
Subject: Re: [NatureNS] kelp flies
> Hi Murray,
> That's an intriguing observation. Roughly what temperature would it have
> been
> when you saw this, below zero? I'm interested generally in flies and
> didn't
> realize that any adults of such groups were around at these temperatures,
> or at
> all in February. As a sort of reference point, I recall reading that the
> UK
> low-temperature record for an insect "behaving" was -5°C for a bristletail
> (wingless insect) that someone observed sitting on a seaside rock in
> Wales,
> whereupon it promptly ran away. I found that it takes a -7°C surface
> temperature (aluminium)to immobilize the same species that we also get
> here
> (they hibernate over winter here in sea cliff crevices). Flies like other
> insects are cold-blooded, and many cell systems like important enzymes
> have
> temperature optima and slow down and eventually shut off when the
> temperature
> drops, so the animals then can't perform at all, e.g. fly around.
>
> I think that 'kelp flies' is a name usually restricted to the family
> Coelopidae,
> with only a few species here in the genus Coelopa. The Manual of Nearctic
> Diptera doesn't mention anything about year-round adults or low
> temperature
> behaviour, though that's not the main thrust of MND so perhaps this
> doesn't
> mean much.
>
> Maybe all this is well-known locally here -- has anyone else seen these
> flies
> flying around recently, for instance while birding around the high tide
> line? They tend to fly in small low clouds around piles of seaweed washed
> up there,
> in summer. If anyone has info and has an idea of what the temperature was
> at
> the time, it would be interesting to hear about it. Do birders ever set
> out
> armed with digital thermometers, now quite inexpensive?
> Steve, Halifax
> ****************************
>
> Quoting dowitcher <dowitcher@eastlink.ca>:
>> on sunday at clam point i had kelp flys flying around in among all this
>> snow.
>>
>> Murray R Newell
>> Cape Sable Island
>> Nova Scotia
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