Subject: re: Caterpillar Drowning

From: [email-masked]
Date: 28 Jul 1995 03:20:59 -0500

I've had similar experiences of sphingid/saturnid larvae 
          committing suicide in this manner.  The most at risk seem to be 
          fully-grown larvae that are about to pupate, of species that 
          usually do so underground or in leaf-litter; it appears that 
          their instinct to seek cover or burrow lets them down in 
          artificial conditions!  However, even larvae that aren't actually 
          looking for a pupation site are at risk. I'd assumed they just 
          blundered down the stems, but the idea they might be seeking 
          water is interesting, I'd not considered this before. I certainly 
          haven't tried spraying foodplant in cages as a deterrent. 
          
          If caught in time, larvae that appear to have drowned will 
          sometimes recover if left to drain on absorbent kitchen roll or 
          similar.
          
          Prevention as always is better than cure!  My solution for some 
          time now has been to put cut foodplant in water in the glass 
          bottles that are used for the soft drink "Orangina" (in the UK 
          at least).  These are about 10cm high, heavy and pear-shaped, so 
          they are stable, hold a reasonable water supply, but most 
          importantly have a narrow neck.  If you can't get these 
          particular bottles, a glass laboratory flask might be a suitable 
          substitute.  It is easy to plug the gaps around the foodplant 
          stems tightly with cotton-wool or tissuepaper, and I find this 
          is proof against even a determined larva.  Don't forget the plug, 
          though; I've lost ten Aglia tau in one night through assuming 
          that they couldn't possibly get through the gap between the stems 
          and the glass!

          Nick Percival
          [email-masked]

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From: [email-masked] (Pierre Zagatti)
Date: 28 Jul 1995 09:33:21 GMT

>          that they couldn't possibly get through the gap between the 
stems 

For my own I use that sort of green foam used to keep fresh
flowers for weeks. You can cut cubes of this material related
to the size of plants. It absorbs water like a sponge without
any risk of drowning.

Many larvae bore the cube to pupate inside the foam.

Furthermore, I used this material to keep nymphs at the right
humidity: naked nymphs extracted from their tight cocoons or
bags (Psychids and Stenomids) or nymphs of beetles found in the bark,
which are quite fragile.

Pierre Zagatti

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From: "D:COMMSDEMONSPOOLMAIL" <[email-masked]>
Date: Fri, 28 Jul 1995 16:02:54 GMT

The name of the green foam in the UK is Oasis - available from all good 
florists and garden centres. 

What a great idea for humidity - I will start using this now.

Andrew Stagg