Tachinid fly killing monarchs

[CrazyConure]

First, I'd like to say that I don't have complete proof that the tachinid fly is killing the monarchs, but I do have some evidence that can help us find out what's wrong.

The other day, my caterpillars were big and fat. The other day, I saw this ugly huge fly. Today, I see all my caterpillars are significantly smaller, and almost all of them were on the floor.

I read online that stunting of monarchs can be caused by the parasitoid tachinid fly. I then looked up what a tachinid fly was and it was that same nasty fly that gave me the jitters the other day!

What do I do? This is terrible! I don't want to keep the monarchs inside the house and take care of them when they are young because they are so messy and poop like heck. I was thinking of getting those nets that they house the monarchs in for kids, and place it over the entire plant as soon as I see eggs are laid.

What would you recommend I do? I have a couple of monarchs on the plant right now. Do I banish them all to prevent the spread of those filthy tachinid flies?

Sorry for long thread.

 

[CrazyConure]

Update: I do see about 3 newly laid monarch eggs on the plant currently. It seems to me like I'm the only food source in Miami, and all the monarchs need me as their food source. I can't let them down. I can't let these tachinids get away with it

 

[roadrunner]

We often classify certain insects as either Beneficials or Enemies; however, nature isn't that neat and organized. There are many so-called beneficials that do things that are not in our favor and sometimes our "enemies" do us a favor.

Many gardeners use to see Praying Mantis as beneficial, but then they learned that they eat everything, including many of the insects that they liked; everybody hates Praying mantis' now The larvae of this fly also can kill other more destructive caterpillars. Only about 10% of laid eggs make it to adulthood. That's why the monarch lays so many eggs, which is in the many-hundreds over their short lifetime.

BTW, you say you saw more eggs laid....be careful, because one of the predators of monarch eggs are monarch caterpillars Just let nature do what it does, all you can do is provide the habitat and the more diverse the habitat the better. Don't worry, the monarchs will be fine, they are not in any danger, regardless what you hear in the news.

This is interesting... http://www.learner.org/jnorth/tm/monarch/Egg_LPB2.html

Excerpt:

"If you watch monarch females that are coming in to lay eggs on milkweeds--anywhere in the country--they usually only lay one egg at a time. There's good reason for that, and I think you know what it is now.

If you find a whole bunch of monarch eggs together that have been laid on a milkweed it means that something is wrong with the female. She's either sick or very, very old and can't hold back. Or, she has been flying along for a long time and several eggs have matured and she lays all of them at once. We really don't know all of the details, so there is a place that one could do a very interesting study."

 

[JBtheExplorer]

the monarchs will be fine, they are not in any danger, regardless what you hear in the news.

Just about every specie that relies on prairie habitat is in very serious danger.
3% - 5% of prairie remaining, and continuing to drop. The majority of that destruction has been done in just the last 150 years. By the time my life is over, prairie will be gone, other than protected lands. Likely less than 1%. That's terrifying. One of the reasons I deeply hope people get on board with native gardening. The trend is growing, but no where near where it needs to be.


Tachinid flies are the least of the Monarch's worries, though. Although they are frustrating for Monarch raisers, they are simply just another part of nature. It's also pretty gross seeing the dead, stretched out caterpillar hanging upside down with a silky string hanging down after the larvae eats its way out. Pretty bad way to die.

 

[Beverly]

Take a look at
https://www.gardening-forums.com/th...ding-hummingbirds-and-butterflies.3547/page-3

post #55 at the bottom of page 3

 

[Marck]

The best method for raising butterfly caterpillars is do so inside of fine mesh cages. Use the cages from from the egg stage onward. Only remove the mesh cage when present and performing a necessary task with the caterpillars. This should reduce losses from predators and parasitoids.

This should also make cleaning easier as any frass and other secretions will fall to the cage floor.
A cage that lifts off like a basket with a separate base is a good design, though a more elaborate cage could also have access doors built into the sides.