Distance caterpillars travel to pupate?

General discussion on entomology
Post Reply
Chuck
Premium Member - 2024
Premium Member - 2024
Reactions:
Posts: 886
Joined: Mon May 23, 2022 2:30 pm
Solomon Islands

Distance caterpillars travel to pupate?

Post by Chuck »

I searched and cannot find any study done on the distance that caterpillars travel from food source to pupate.

Anecdotally from my own observations:
* Euphydryas phaeton: about a meter if the Queen Anne's Lace stalk is nearby (which it usually is)
* Samia cecropia: maximum maybe four meters
* Callosamia promethea: zero, if they can avoid it
* Papilio glaucus: I found one larvae last fall hundreds of meters from the nearest food source

Of course, the question as phrased is very generic, and I'm sure some travel cross-country or some obscene distance.

@eurytides uses brute-force to find Mid Summer Tiger larvae; I was thinking it would be easy enough to go search for the pupae, but in light of my Papilio glaucus (actually, it too MST) larvae last year so far from the food plant, I'm thinking that would be a waste of time. Still, I know the bug feeds in my back yard, the pupae must be somewhere.
User avatar
kevinkk
Premium Member - 2024
Premium Member - 2024
Reactions:
Posts: 313
Joined: Mon May 23, 2022 5:06 pm
Location: Oregon
United States of America

Re: Distance caterpillars travel to pupate?

Post by kevinkk »

Yes, the pupa must be somewhere. I think there are two mitigating factors, the species, and individual behavior. I have found wild Papilio rutulus
pupa before, at the base of a hundred foot tall poplar tree under a board. they clearly traveled some distance to pupate.
I had a brood of luna raised uncaged indoors once, many spun in the branches, but some went into other rooms...
After raising a number of different species indoors, I noticed that some species will purge, and begin spinning, others will go to the cage floor and wander around. They seem to do the same thing outdoors in a sleeve as well, some wander and some don't. whatever they're looking for, only the
caterpillar knows, it all looks the same to me.
I don't find many pupa or cocoons outdoors, for one thing, I don't go out in the snow covered mountains in the winter, over the years most of us
have happened upon a wayward overwintering pupa, usually a cocoon hanging from a branch or under the eaves of a building.
That sounds like a good study for some students.:)
eurytides
Meek
Meek
Reactions:
Posts: 196
Joined: Tue May 24, 2022 1:36 am
Canada

Re: Distance caterpillars travel to pupate?

Post by eurytides »

I have raised numerous species and how much time the larva spends wandering is species dependent. If you assume caterpillars crawl 1 cm every 3 seconds and they crawl for 6 hours, then you are looking at 72 meters. Of course, they don’t crawl in a straight line, sometimes they double back, and the crawl rate will not be at a maximum every second. Even so, a dozen or more meters could be reasonably expected.
User avatar
kevinkk
Premium Member - 2024
Premium Member - 2024
Reactions:
Posts: 313
Joined: Mon May 23, 2022 5:06 pm
Location: Oregon
United States of America

Re: Distance caterpillars travel to pupate?

Post by kevinkk »

Wouldn't the speed of a larva depend on it's size? I know larva can motor right along, and I would guess the species that travel the furthest would be
burrowers like Sphinx. I've never thought about how fast they crawl- just how fast they can escape my eye when changing food plant, I know they will
travel a long way at times, I've found what were clearly escapees from a sleeve many yards from the food plant, and some are made to wander,
we went road hunting this fall for wooly bears and other Arctiidae, they can really get going on a warm road.
eurytides
Meek
Meek
Reactions:
Posts: 196
Joined: Tue May 24, 2022 1:36 am
Canada

Re: Distance caterpillars travel to pupate?

Post by eurytides »

Yes, there are many factors, not just the ones I mentioned. Body size certainly counts. All of this is to say that distance is highly variable but some species can crawl many meters (double digits) to pupate.
User avatar
Paul K
Meek
Meek
Reactions:
Posts: 176
Joined: Mon May 23, 2022 6:44 pm
Canada

Re: Distance caterpillars travel to pupate?

Post by Paul K »

They are preprogrammed for crawling a certain distance.
The good example is a round jar or container for Sphingidae larvae or any other species which pupate underground. The caterpillar will pass the ideal spot to bury multiple times and finally bury it self at the same location. They don’t really recognize location or are aware of its surroundings and I suppose of it’s existence at all.
eurytides
Meek
Meek
Reactions:
Posts: 196
Joined: Tue May 24, 2022 1:36 am
Canada

Re: Distance caterpillars travel to pupate?

Post by eurytides »

I don’t think the distance is set. If a larva is making a cocoon, and you take it and move it somewhere, it doesn’t crawl that same distance all over all. If crawls a much shorter distance and makes a second cocoon much sooner because it’s running out of time.
User avatar
Paul K
Meek
Meek
Reactions:
Posts: 176
Joined: Mon May 23, 2022 6:44 pm
Canada

Re: Distance caterpillars travel to pupate?

Post by Paul K »

It is then kind of set as if it did travel the distance and it is disturb it won’t travel again, as you mentioned it runs out of the time on the clock.
eurytides
Meek
Meek
Reactions:
Posts: 196
Joined: Tue May 24, 2022 1:36 am
Canada

Re: Distance caterpillars travel to pupate?

Post by eurytides »

But it still travels some more, so there is no set distance. If you took 10 caterpillars and they were clones, there is no way they would all travel exactly the same distance. Mayne one travel during a hot day and another during a rainy cool day. There are many factors. The distance is not going to be a constant.
User avatar
Paul K
Meek
Meek
Reactions:
Posts: 176
Joined: Mon May 23, 2022 6:44 pm
Canada

Re: Distance caterpillars travel to pupate?

Post by Paul K »

I agree, it won’t be exact distance for all specimens within a group but one species will travel more or less than another.
eurytides
Meek
Meek
Reactions:
Posts: 196
Joined: Tue May 24, 2022 1:36 am
Canada

Re: Distance caterpillars travel to pupate?

Post by eurytides »

Yes I agree, different species have different tendencies to travel. Like mentioned earlier, some species crawl off the host plant but others pupate or spin cocoons on the host and hardly move.
User avatar
kevinkk
Premium Member - 2024
Premium Member - 2024
Reactions:
Posts: 313
Joined: Mon May 23, 2022 5:06 pm
Location: Oregon
United States of America

Re: Distance caterpillars travel to pupate?

Post by kevinkk »

Paul K wrote: Thu Jan 12, 2023 6:30 pm They are preprogrammed for crawling a certain distance.
The good example is a round jar or container for Sphingidae larvae or any other species which pupate underground. The caterpillar will pass the ideal spot to bury multiple times and finally bury it self at the same location. They don’t really recognize location or are aware of its surroundings and I suppose of it’s existence at all.
I have to jump in at least once more- One year I raised a few Citheronia regalis, I put each one in a 5 gallon bucket nearly full of potting soil and
put on a lid. A few days went by, and the larva was still going around in a circle along the bucket sides. Ok, I have a solution for that..
I set a rock in the way on the well worn path. the next time I opened the lid, the larva had burrowed in. I wonder how many times those
caterpillars crawled along the sides of that bucket, maybe the circular container confused them somehow, the rock certainly set them straight.
My last brood of sphinx I simply used sphagnum moss in a box, they disappeared into the material and presumably crawled around a bit before
settling down.
Chuck
Premium Member - 2024
Premium Member - 2024
Reactions:
Posts: 886
Joined: Mon May 23, 2022 2:30 pm
Solomon Islands

Re: Distance caterpillars travel to pupate?

Post by Chuck »

Kevin, I'm sure you posted that anecdote before concerning C regalis, and in fact I also read it in a publication recently.

To my mind, the question is not how far a larva CAN crawl, it's often how far it WILL. Clearly, promethea often don't even leave the tree, though I'm sure they could crawl quite a distance. In some cases (e.g., Hemileuca used-to-be-maia buck moth of the bogs) has a specific destination it is looking for; typically this is found within a couple meters.

In the case of the glaucus MST larvae I found so far from the foodplant, I wonder what it was looking for; it had passed several buildings, and I know they like the sides of buildings, but of course I doubt it could even see the building unless it ran into it. But certainly, I never find them on the trunks of the trees that they are feeding on, not like cecropia.
Post Reply

Create an account or sign in to join the discussion

You need to be a member in order to post a reply

Create an account

Not a member? register to join our community
Members can start their own topics & subscribe to topics
It’s free and only takes a minute

Register

Sign in