Pumpkin as diet for larvae

[Jacqui_in_NZ]

Hello all from New Zealand

In this morning's mail to the Monarch Butterfly NZ Trust is a series of photographs sent in by a man who is feeding his fourth instar Monarch caterpillars on pumpkin when he runs out of the milkweed we have growing here in NZ.

He says "...fine slivers of pumpkin placed flat on the bottom of a box with the caterpillars placed on the internal cut edge produced the best results. It also became evidently fairly early on that very small caterpillars did not have the strength or intestinal fortitude to make the change."

We receive many requests from members for advice on alternative food sources, and I wonder if there is any scientific evidence as to any effects pumpkin as a diet for finishing caterpillars would have on future generations - it would be good to know this, before putting this information and photographs on our website.

Hope some of you might have some information, and thanks!

Kia ora

Jacqui Knight

[Pamela Moresby]

I'm from NZ too. Just last year, discovered South African Swan plants at Roger Hunters at Tidal Rd in Mangere Ak. It has orange flowers.

Caterpillars will eat anything that has white sap at a pinch but prefer the swanplant. I have had to feed them on Kapok or Capok as there was nothing else. Tried the pumpkin. However, I don't let the caterpillars eat the pumpkin ,or kapok for too long.

Pam

[Jacqui_in_NZ]

What part of NZ Pam?

Good to hear from you!


Jacqui

[Jim]

Hi Jacqui:

We'd love to hear more about this and see the photos if you feel like sharing

We have heard this many times over the years (mostly if not exclusively from NZ) but have been given no quantitative details - we are going to try to conduct our own diet trials later this season so we'll report our findings then.

Jim

[Jacqui_in_NZ]

Hi Jim,

Fascinating isn't it? Not sure if I can upload photographs here, but in the meantime, you can see his report and photographs here:

http://monarch.org.nz/monarch/2005/08/13/pumpkin/

I phoned the couple back to find out if the pumpkin was organically grown - thinking that might be a cluse - or home-grown, or a specific type of pumpkin, but she told me that she just used whatever was in the shop at the time, and sometimes it was home-grown, but they grew nothing special.

I had tried it myself many years ago, using a dish standing in water like a moat, to "force" them to stay at home, but it wasn't a huge success I seem to remember. I did learn that it would definitely not work unless you selected caterpillars in their last stages, my rule of thumb was about 2-3cm long.

[Pamela Moresby]

Dear jaqui,

I live in Onehunga, Auckland NZ.
Thanks for the reply
Pam

[Megathymus ursus]

Never heard of pumpkin as an alternate diet. Some WILD pumpkins (i.e. Cucurbita foetida) have very toxic alkaloids that may be similar to what is in milkweed, but I haven't done any experiments. If someone wants to sacrifice some caterpillars for this type of test, it might be well worth it.

Do be aware that not all alternate foods a caterpillar may eat are suitable replacements. Ursine Giant Skipper (Megathymus ursus) larvae will dig right into sweet potato (their normal host is yucca root), but will not grow. They will just eat and eat and eat into the sweet potato and eventually die of malnutrition, for it does not have what it needs.

[Jacqui_in_NZ]

Hi Meg -- will be interested in what you find out!

Right now I'm into a balancing act, trying to keep eough feed for Monarchs, and being given branches of Swan plant and finding enough caterpillars to eat it before it dies. I'm winning so far! I'm not going to let the caterpillars live outdoors, where the wasps will get them.

Jacqui

[Megathymus ursus]

Well, I have my hands full just dealing with the disease that has killed all of my monarch pupae over the past year. My current batch of larvae, which I have reared outdoors, in bleach-sterilized tubs, on milkweed leaves rinsed with full-strength bleach, have all pupated. Let's see if the pupae will avoid getting the black streaks and patches that signify their destruction...

PS what is a "swanplant"?
Brian

[madmonarch_nz]

Hi,

Im in NZ as well and my swan plant is swarming with yellow aphids & lots of holes in the leaves,problem is that I have nearly 20 caterpillers in varying sizes so am not wanting to spray the plant with anything, can I use pumpkin? and what sort of containers can i put them in? I do have a large aqurium tank not in use at the moment can i use that? Also what is the best position to put them in?

Am really wanting to rescue these little fellas.....not only to be released back into the wild but for the photography side of things as they make beautiful pictures.

Many thanks in advance

[Jim]

Getting rid of aphids doesn't necessarily require the use of pesticides...you can simply wash them off the plant(s) with a garden hose. If you want to raise the monarchs in that aquarium using cut plants, simply snap off the leaves, rinse, pat dry, and feed them to the larvae.

The jury is still out on pumpkin as an alternate food source - if you are able to run a little experiment we'd love to hear the results!

20 caterpillars in an aquarium should be just fine - just make sure to keep things clean (a layer of paper towels changed every other day or so helps a lot), keep the caterpillars out of direct sun, and watch the humidity levels (a screened top would be great). Good Luck!

BTW Brian, "Swan Plant" is a milikweed - Asclepias fruticosa.

[madmonarch_nz]

Cool thanks heaps, will definately give the pumpkin thing a go I remember using it when I was young so will let you know the results

[madmonarch_nz]

Ok i posted a sepereate post but as you can tell by my sig Ive started up a little experiment of my own regarding Pumpkin vs Swan plant.

Just thought i would let you all know

[chabeda]

Yesterday we fed our Monarch caterpillars (regular) cucumber, English cucumber, yellow squash and zucchini. They liked all of them. [organic]

We only gave them the skins.

We were running out of milkweed so yesterday we tried this.

We couldn't find any raw pumpkin.

We don't know if they will turn into chrysalises, but we hope they do.

As far as we know, we are the first people not in New Zealand to report this. (We live on the West Coast of the United States.)

[chabeda]

Very good news.
Sat. night at 10pm 7 Monarch caterpillars were fed vegetables (each caterpillar only got 1 kind.) They jumped on the vegetables and devoured them because they were hungry.

They had been eating and eating and eating for a 3 1/2 days.

Sunday, the caterpillars didn't move much. They weren't eating hardly at all. I was worried that they had gotten food poisoning.

However, I did notice that the 2 caterpillars being fed yellow squash seemed to like it a lot.

When the caterpillars were moving so little, I gave each one (I think) a milkweed leaf.

I put zucchini peel in each container (except one caterpillar only fed milkweed) since that vegetable changed the consistency and color of the poop least. Those fed yellow squash had reddish-orange liquidy poop.

But I noticed the 2 in the yellow squash container almost seemed to like yellow squash better than milkweed (or zucchini peel). They stayed on the squash (peel) and seemed to be eating it instead of milkweed.

By the way, I believe what is called "telegraph cucumber" in New Zealand is called "English cucumber" in the U.S. and is quite easy to buy. (They look the same in the photos, and are described the same way.)

I believe we are the first people in the world to report that Monarch caterpillars can eat yellow squash, and that they can pupate after eating yellow squash.

So Sunday night at 7pm the caterpillars climbed to the top of the (yogurt) containers and started making white silk thread on the plastic (cellophane) wrap on top.

At 9pm, they formed into J shapes.

This morning (Monday) at 9am, 3 of them turned into chrysalises.

The first one to pupate was one that was fed yellow squash peel.

The second one to pupate was fed zucchini peel.

The third one to pupate was fed English cucumber peel.

There are 2 more hanging as J's.

We are exceedingly pleased because the only thing we've done before in terms of raising butterflies is raising 4 painted ladies from the kit.

[chabeda]

I moved this report to a new thread.
http://www.monarchwatch.org/forums/view ... =2222#2222

[ORANGEMUSTANG]

I am very new at butterfly gardening. I planted two milkweed plants this spring. One from ebay (red) and one from home depo(yellow). Both now have tiny white eggs under the leaves.
I am worried that I won't have enough plants to go around. Will nature thin the eggs out or will they all hatch and possibly starve?
BTW. I bought 18 fennel and dill plants yesterday and I had lots of hitchhikers! I was pretty excited by this. 10-15 baby cats.

[chabeda]

feed them milkweed as long as you can. if you start to run out, feed them the yellow squash skin and see if they survive. mine seemed to do fine.. do read the new thread.