Orange Tip Chrysalis

[NickMorgan]

Earlier in the year I found loads of orange tip caterpillars on some garlic mustard plants. Today I returned to the area to see if I could find any chrysalises, without any luck. Has anyone any advice on where they are likely to be?! Any pictures I have seen, they appear to be on quite narrow stems. I have tried looking at the dried out stems of the garlic mustard and on dock seed heads and nearby alder and hawthorn bushes. Does anyone know what sort of height above the ground they are likely to be at?

[Jack Harrison]

I breed them most years from eggs. I have found caterpillars easily enough but never chrysalids.

I didn't manage to breed any from eggs found in 2011 as I was in the middle of a domestic upheaval during the Orange Tip season. But I still have three or four chrysalids from eggs that were found in 2010 that still look perfectly healthy - one indeed is the green form and certainly there is no reason to believe that is not still alive. So maybe they will emerge in late spring 2012 almost two years since they were eggs. I have in the past over-wintered chrysalids twice by keeping them artificially cold in the fridge, but these current ones enjoyed normal summer temperatures in the garage.

Jack

[NickMorgan]

That's interesting. We still have five or six small white chrysalises on our house that didn't do anything this year. I will make sure we leave them there until next year just in case they emerge then. (Maybe they knew we were going to have a lousy summer!)
I have often wondered what stimulates chrysalis emergence. Is it a sustained period of warm weather, or is it daylight length? It must be different factors for different species. I am sure that someone must have experimented with this in the past.
I'll go back and look some more for orange tip chrysalis next week. I read somewhere that the caterpillars travel some distance before pupating, so maybe I need to search a wider area.

[Jack Harrison]

Nick Morgan:

read somewhere that the caterpillars travel some distance before pupating, so maybe I need to search a wider area.

Good idea Nick. You are in East Lothian, I am in West Norfolk. Have a look in my garage and you might be in luck

Jack

[Gibster]

Hi Nick,

A few months ago I found an Orange-tip pupa affixed to the foodplant, Garlic Mustard in this instance. Obviously it had not read the bit in the book that states they wander off to pupate! It was approx 3ft up the plant. Hope that helps?

I bumped into Jack earlier this year. He advised me that Orange-tips generally favour Garlic Mustard plants growing beneath a hedgerow as opposed to those growing away from woody vegetation, allowing the larva to pupate on something tall and nearby. So saying, I've often found the eggs on Cuckooflower growing quite some distance from ANYTHING taller than grasses and rushes, so can only assume that these caterpillars either wander a good distance to pupate, or else pupate very low down - which seems less likely. I guess butterflies that pupate 'upright' with a silken girdle typically need tallish vegetation/fenceposts etc, and also something which is going to remain upright until their emergence.

Cheers,

Gibster.

[NickMorgan]

Thanks Gibster. I have checked out all of the garlic mustard plants and other annual and perennial plants nearby. The area is close to a river and potentially could be prone to flooding. I also thought that the more flimsy plants could be likely to be knocked over when it snows. Further up the bank there are some hawthorn bushes, so I will have a look there. I guess that orange tips may have evolved to pupate on plants where they are less likely to be flooded or crushed by snow!

[essexbuzzard]

This is an interesting subject,please keep it going. I too am interested to know where the caterpillars pupate, as i have never found a wild chrysalis,despite searching plants which held the earlier stages.
Also,the females seem very choosy in where they lay their eggs. In my part-shaded garden i grow garlic mustard,but they seem to avoid mustard growing in bright sunshine,prefering to lay on shaded plants,so only a percentage of mustard plants are used. Yet the adults use these sunnier areas happily.
Cheers all
Mark.

[Piers]

Chrysalids are often formed upon the stems of garlic mustard (when this is the chosen food plant). They are, however, surprisingly camouflaged.

I shall take a photograph of three pupae on an honesty stem growing at the back of the garden; honesty is readily used as a larval food plant in gardens. Apologies in advance as I shall be using a telephone with which to take the pictures. The only reason that I spotted these particular pupae was that being green all three stood out against the dried old honesty stems which I was about to cut down and consign to the bonfire. Of course, when the larvae pupated earlier in the summer, the pupae would have been superbly camouflaged.

Piers.

[hystrix]

I grow Garlic Mustard plants in my garden and find Orange-tip larvae on them every year. One year I noticed 2 larvae suspended on the foodplant in preparation for pupation.

Last year I noticed an Orange-tip pupa attached to a trellis on the back wall of my house. This is some 5 metres or more from the nearest food-plant. It must have travelled across a gravel path and up a step to get there. I kept an eye on it in Spring this year, and was lucky enough to photograph it emerging in early April:

[ChrisC]

love that 2nd shot,

Chris