Hooray for small favors! At last a caterpillar that won't destroy my landscape plants and trees. The Monarch caterpillar eats milkweed leaves and nothing else. Farmers love having the Monarch as a guest to rid fields of the persistent milkweed plant.
The sap of milkweed leaves contains a chemical called cardiac glycoside. This chemical is stored in the caterpillar's body. If a predator tries to attack the monarch caterpillar, it will taste this repulsive, poisonous chemical. Ingestion of the Monarch caterpillar usually results in illness.
The day before the monarch caterpillar emerges the egg turns black. After the caterpillar emerges from its shell, it eats it! It grows and grows during its time in the larval stage of its life, which is about 14 days. In fact, a monarch caterpillar can grow over 2,000 times its original mass! Its main responsibility
during this time is to eat plenty of food. This weight gain is important in determining how big the monarch will be as a full-grown butterfly. The large amount of milkweed leaves allows the insect to store a lot of lipids that are useful when it is an adult trying to survive the winter.
A monarch caterpillar goes through five different stages called “instars.” The caterpillar grows bigger and molts its skin throughout each stage. The official term for a caterpillar's skin is “cuticle.” The caterpillar also has an exocuticle, which is a waxy substance that protects the insect from losing water.
The body of a monarch caterpillar is fascinating. It has three pairs of true legs connected to its thorax, and it also has a few pairs of prolegs connected to its abdomen. The prolegs have tacky pads called crochets attached at the bottom.
Monarch caterpillar predators have a special technique for finding their prey. They observe milkweed leaves for damage giving a good indication that the Monarch caterpillar is present. However, the caterpillars also know how predators can find them, so they do a lot of moving from leaf to leaf, leaving no forwarding address.
Another escape tactic for the Monarch caterpillar is to use silk as a type of rope. If it senses a predator nearby, the caterpillar can crawl down to the ground by dispensing a string of silk. Like many other types of caterpillars, it will curl up into a ball and do the “play dead” routine when touched.
A Monarch caterpillar will give off certain clues when it is ready to pupate. First, it will stop eating. Second, it will move from the milkweed leaf it was living on, moving to a safer place. Finally, it will hang off a twig or leaf in the shape of a “J”. Within a day, the monarch caterpillar will form into a chrysalis. (Interesting fact of the day: A butterfly develops from a chrysalis, but a moth develops from a cocoon.)
Because Monarch caterpillars have a diet that entirely consists of milkweed leaves, they will not pose a threat to your garden or yard. They are also relatively harmless to humans. These unique caterpillars grow into beautiful butterflies, so if you see them near your home, they will be fun to observe as they go through the stages of metamorphosis.
Comments
Vicky
28 Apr 2009, 13:48
I just watched in horror as a wasp attacked and killed one of my monarch
cats. I had been worried about not having enough milkweed to feed them
through, now I wonder if I will have any cats make it to butterfly stage.
That dang wasp ate half and then flew off with the head and sat on a
chyrsanthamum to finish it off.
carol
29 May 2009, 11:29
I have had to cat casualties too wasps. I have a lot of cats so I am
winning. Is there anything I can do to get rid of the wasps. both of my
cats were close to crawling off and becoming butterflies. boo hoo
Pru
07 Jun 2009, 22:02
I have come home to find my cat had fallen of the tree and was curled up in
a ball after having him thaw out on my hand I put him back on a new plant,
more to eat for him not to be able to stay on the plant, he kept falling
off. He has made lots of strange movements including rolling on his back
is this normal or dear I say it will he perish today?
Merle
08 Jun 2009, 02:34
I am having the same problem as Pru. I am in new Zealand and have never had
cats in June before, even my hangers, the ones waiting to cocoon, have been
dropping. I still have a large amount of cats and plenty of food but it is
heartreaking watching them die, probably because of the extreme cold.
Pru
10 Jun 2009, 15:48
I know you shouldnt but i have been brining my plants in at night and my
cat that looked like it was going to give up the ghost is now hanging off a
leaf by a thread literally so I have my fingers crossed he still might
cocoon
Nick M.
13 Jun 2009, 16:58
As the earlier posters mentioned, I too have just seen a cat be eaten up by
a wasp. Not sure where the wasp colony is. How do you get rid of an
individual wasp next time I see it around the milkweed? Also, does this
mean that the wasps are watching the milkweed plants (which, BTW, have lots
of holes - and small cats - on them)?
DEe
22 Jun 2009, 21:41
My milkweed is almost gone 40 + cats on one plant. Should I get another or
have they eaten enough? Where do they make and hang their chryssalis from?
Mary
20 Jul 2009, 14:57
We had an infestation of milkweed bugs that left our milkweeds bald so I
went out and bought 4 healthy milkweeds and relocated about 30-40 cats to
the new plants. They are very happy, but everytime I out to check on them
I see less and less on the leaves. Are they being eaten? I live in the
Central Florida area. Our backyard backs up to a conservation area. What
would eat my little guys? I'm not even seeing remnants on the ground.
They're just gone. I should see at least 17 on one of my plants and I see
maybe 4.
Barbara Garrison
27 Jan 2010, 22:20
My Monarch caterpillar hatched late in the Fall.
It is winter now and I brought the entire Parsley Plant inside. He was
hanging from a Parsley Plant stem this morning and fell off. What should I
do?
Thank you for any help you can give me.
Sincerely,
Barbara
Mary
28 Jan 2010, 10:26
Check this out Barbara. Good luck.
http://www.monarchwatch.org/forums/viewtopic.php?f=6&t=781
lynette greenfield
20 Mar 2010, 20:37
This is my first time that I have had a swan plant.please excuse my
ignorance but I gather that a cat is a caterpillar,right?I have cut off
branches of the swan plants that have a lot of eggs on and bought them
inside in a glass jar.So far have seven chrysalis and quite a number of
caterpilars.I hate the idea of them being eaten by wasps or whatever.I am
from central new zealand
Barry
28 Apr 2010, 03:16
I have two swan plants.
A while back I counted 14 monarch caterpillars on one plant, but none on
another.
Soon after they stripped plant one bare and no caterpillars were seen.
Soon after ( a couple of days) I counted 9-10 caterpillars on the other
plant, where none were before.
The distance between the two plants is about 10 metres, with soil and a
wooden fence betwee.
Is it possible that the cats travelled from the first to the second plant-
under their own power?
Thanks.
Ask the Exterminator
28 Apr 2010, 08:45
The cats do move quickly and often as they forage for food. My guess is
that you were looking at the same group of caterpillars.
Mary
28 Apr 2010, 12:08
Barry, I think it was the same group of cats too. They do travel quickly.
I don't know if I should do this, but I find myself gently picking them up
and moving them to plants that have plenty of leaves. It doesn't seem to
bother them as they start eating again pretty quickly. They are pretty
fascinating little creatures.
Chrissy
24 Jun 2010, 11:35
I have had several Monarch caterpillars on milkweek, and all of a sudden
they are gone, I checked all the milkweed plants! is there something that
is eating them? I had one this morning that was approx 2 inches long, I
though for sure it would build a chrysalis today on the milkweed, but when
I went out to check, he was gone and no chrysalis...Where oh where did he
go?
Ask the Exterminator
24 Jun 2010, 12:10
They move as they search for new food.
Chris
21 Jul 2010, 09:42
I am wondering if there is something more going on than the cats leave to
search for food. I have about 20-30 milkweeds in a garden and found 9 first
or second instar staged cats on them, the next day all were gone. I cannot
find them anywhere and I've looked repeatedly the past few days. They are
on milkweeds which is their feeding plant, why would they leave to forage
for food elsewhere?
Ask the Exterminator
21 Jul 2010, 11:21
When caterpillars are ready to pupate they often leave the plant where they
were feeding to find a peaceful spot. That spot may be up to 30 feet away
from where they were eating.
If it was a small caterpillar a spider could have eaten it. Bold Jumping
spiders do this frequently.
cinda shaffer
25 Jul 2010, 12:16
in southeast iowa usa i have now seen wasps eat (and suspected spiders were
eating) monarch cats off the plants. this week i saw a male cardinal land
on a plant, apparently looking for food (with a full bird feeder nearby).
today i found an infestation of milkweed tiger moth cats on one of my
plants, with huge devastation of the plant. cinda
butterflylover
06 Aug 2010, 19:18
If you are worried about your cats being eaten try to put then inside in an
aquarium. I have mine inside and they are doing wonderfully!
Mary
15 Aug 2010, 13:03
This is my 4th season for my New Jersey butterfly garden. There is a new
insect this year, I cannot seem to identify. Lives on the milkweed, has a
bright red abdomen, and small black head, travels in groups, and is very
fast moving. Does not seem to be congregating around the seed heads. I
thought it was a milkweed bug, but cannot find any pictures that truly look
like he insect in my garden. I am afraid it may be an assassin or wheel
bug. What should I do? Squish or watch?
Ask the Exterminator
18 Aug 2010, 12:51
I cannot make a recommendation without an ID. I don't know what to tell
you.
Brady
28 Aug 2010, 11:50
I know i have the same probleme to Mary and I don't know what to do. If you
go to google and type in milkweed bug then go to images that is what i have
on the big seed pods on my milkweed plants.
Ask the Exterminator
28 Aug 2010, 17:55
Anything you would use would also kill the Monarch Butterfly larva that
also feed on this plant. Live and let live.
Elizabeth Gillette
03 Sep 2010, 09:32
I have lost 5 Monarch caterpillars in two days to the Bloosucking Conenose.
I rescued and brought inside 5 living cats. Is there a way to kill this
predator without harming the cats? I live on an old farm in Ossipee, NH,
with much milkweed. Last year we saw zero Monarchs. This year we saw five
butterflies in August - enough to lay eggs.
Ask the Exterminator
03 Sep 2010, 09:41
I don't recommend messing with Mother Nature's plan. Kill off one insect,
end up with two more. Let nature take its course.
Robin
16 Sep 2010, 15:47
There is an immature stink bug that kills caterpillars. I just found one in
the act of eating one of my Monarch babies, and confirmed it by checking
the photo on this website:
http://www.whatsthatbug.com/2010/08/02/immature-predatory-stink-bug-eats-mo
narch-caterpillar/
I live in Kentucky.
I checked all my milkweed and picked off three of the stinkers. Flushed
them down the toilet. The Monarchs need help due to habitat destruction;
and I'm not aware of any shortage of stink bugs.
Kristen
08 Dec 2010, 19:41
I am in NZ and have just seen a brown ground beetle attack and eat a
caterpiller. It seems the monach caterpillers have a number of different
enemies.
Kathy
14 Mar 2011, 12:34
I am in Bermuda. I bought a small milkweed plant and it has six
caterpillars on it. Unfortunately the biggest one eats a ton and probably
after two more days, I will have no more leaves on my plant. What to do?
Should I go buy another plant and transfer them or should I visit the
botanical garden and take a few fresh leaves for them every day? Thanks for
the advice!
Ask the Exterminator
14 Mar 2011, 12:37
Personally, I would do nothing at all other than allow Mother Nature to
take her course. The caterpillars will relocate to find more food without
any help from you.
Chrissy
14 Mar 2011, 12:40
Kathy, you definitely need to buy SEVERAL milkweed plants...a growing
caterpillar will eat 8 leaves per day or more! if you do not they will die.
Home Depot carries Milkweed.
Jennefer
13 Apr 2011, 08:37
When I went to bed last night I had 3 monarch chrysalis hanging from a
board on the fence (about 3 ft high) and one on a leaf of the milkweed
plant as well as one cat hanging in a "J" ready to cocoon. When I woke up
this morning all 5 are gone! What could have happened to them? I have 5
more chrysalis that are up high hanging off my covered patio (about 9 ft
high) that were not disturbed. Does any animal eat the actual chrysalis?
Ask the Exterinator
13 Apr 2011, 10:12
Spiders and birds will attach cocoons.
Ida OConnor
04 Jul 2011, 01:21
Hi, I have a Passion Flower plant that the Monarch Butterflies love. Now I
have the whole life cycle going on and I really need to know if spider's
eat the chrysillas. They are very smart and fly infront of my window to let
me know if a caterpillar needs help crossing the black rock on our front
wall due to the fact that it gets very hot and almost cooks then like a
frying pan. So I'll get them and put them somewhere that is shady. They
also have been drinking outta the Humming Bird feeder lol. I just want to
know if there is anything that I can do better to help these little guy's
along. I had no idea that Passion Flowers attracted butterflies.
Ask the Exterminator
05 Jul 2011, 14:17
Although I cannot say for certain, I would suppose that birds, spiders and
a host of other predators will eat the chrysillas. Just remember, as you
"help" the butterflies survive, you are hurting birds and other species
that need to feed on the butterflies.
Stacy Nourse
14 Jul 2011, 11:24
Hi, I am actually a newbie to raising catepillars indoors. I live in
southwest florida. I bought those butterfly habitats and cut out the
bottoms so i keep a paper towel on the bottom and just change it regularly.
I've done alot of research online. I have about 47 catepillars, 3/4 of them
are in chrysalis stage now. I am almost out of milkweed and i've been kind
of "starving them" so to speak. I give them what I have and i even scrape
off some of the stems so they have some food available. I actually have
about 10 that are in their last stage and they are still eating like crazy.
I don't know what else to do. My local greeneries don't have any milkweed
available right now. I even went so far as to put them up on the top to see
if they would just change to a chrysalis. Then I find a catepillar eating
another that was hanging like a J. HELP. Not sure what I can do to save
these cats. I didn't meant to raise so many. it just happened and it
sounded like fun at first...but now I'm just day by day praying that they
turn into a chrysalis...lol...
Ask the Exterminator
15 Jul 2011, 16:13
Sorry! I cannot be of much help. I'm an exterminator, not a biologist.
Teresa
17 Sep 2011, 15:19
I live in State College in Central Pennsylvania and just had an amazing
experience bringing in, for the night, a Monarch. It was holding on to the
chrysalis when I found it. It flew away this morning, after a gatorade,
sugar suryp, soy sauce meal. She was beautiful. My question: I just found a
catapillar on my milkweed. Should I try and ship it to someone futher south
and west or leave it alone? I suspect it will not make it through the
chrysalis stage before we have feezing temps.
Ask the Exterminator
18 Sep 2011, 08:08
I am a believer in allowing Nature to take its normal course. Return it to
where you found it.
