Brian Watson wrote:

[-]

I have a lid on mine but I assume the parents got in where the inpipe passes
through that lid.


Had another look this morning.

The bodies have a kind of blotchy, almost zigzag dark pattern when viewed
from above, and the pipe-type "tail" is actually about as long as the body.

Any ideas?

Some type of hoverfly larva? Specifically that known as the 'rat-tailed
maggot', the larva of the Drone Fly _Eristalis tenax_ (the tube is very
extensible). I have these in my half-barrel 'pond' and would not be
surprised to find them in a water butt to which the adults could gain
access. They are harmless, and the adults are good pollinators.

http://res2.agr.ca/lethbridge/scitech/kdf/rat_e.htm


regards
sarah



--
Waist deep, neck deep
We'll be drowning before too long
We're neck deep in the Big Muddy
And the damned fools keep yelling to push on