We Can Now Track Individual Monarch Butterflies. It’s a Revelation.

The New York Times ^ | Nov. 17, 2025 | Dan Fagin, Jonathan Corum

[Terabitten]

Most monarchs weigh 500 to 600 milligrams, so each tag-bearing migrator making the transcontinental journey is, by weight, equivalent to a half-raisin carrying three uncooked grains of rice.

I swear Americans will do anything to avoid using the metric system.

[rexthecat]

I saw millions and millions of them once while driving home from work in Rancho Cordova California. An amazing site, right up there with seeing the Northern Lights.

[exDemMom]

I had a monarch fly through my yard right after I planted some flowers.

Of course, before the squirrels ate the milkweed I was trying to grow, I didn’t see a single monarch. Milkweed is supposed to be their favorite food.

They are migrating right now.

[tumblindice]

The only reason euros use the metric system is their weenies seem bigger in centimeters.

[Eccl 10:2]

“The breakthrough is the result of a tiny solar-powered radio tag that weighs just 60 milligrams and sells for $200.”

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“But we’ll never use these to track humans. No sir!”

[frank ballenger]

The 1950s Popular Science cover stories of flying cars and commuting to cities on the Moon didn’t work out.

But we can put sensors on butterflies.

[jerod]

They survive on milkweed... Sadly... Because Al Gore convinced the government to incentivize ethanol production... Large tracks of milkweed were destroyed to grow corn for that ethanol production... Sorry Monarch butterflies... Another f'up by the same man who gave us mercury filled lightbulbs to pollute landfills with, also managed to destroy your food supply.

[Paal Gulli]

"...Milkweed is supposed to be their favorite food.

No, it's their only food, for caterpillars anyway. The adults won't lay their eggs on anything else.

The caterpillars feasting on the bitter milkweed sap is supposedly what gives the adults their unpleasant taste, which is why the usual predators want nothing to do with them.

[Ronaldus Magnus III]

Solar Powered?

So, if the Sun does not shine, will they have to fly many airplanes over the Monarchs with huuuuge floodlights to power the tracker?

[Southside_Chicago_Republican]

I have seen a few this year. I am always amazed how the little buggers make that kind of migration.

[Carry_Okie]

The primary reason for the drop is likely a combination of exotic Oleander aphids (Aphis nerii) attacking milkweed (Asclepias fascicularis, at least around here) and also other exotic weeds and higher order perennials (trees and brush) displacing milkweed. Bugs need their hosts or they don't make it. 95% of what birds feed their young is caterpillars. And so on.

I can say with some hard-earned authority that the big challenge with the above is that bugs are not capable of extended dormancy as are plants. If the plants stop germinating and fruiting, no bugs. No bugs, no birds. That's how it works. The problem is worldwide. The mass of bugs in Germany is down 75% over the last 30 years.

Perhaps the most destructive element in this ugly equation is that leftists are in love with "preserving the environment" thus precluding all disturbance necessary for the germination and flowering of native annual plants. They also hate herbicides necessary to get a grip on those weeds the bugs can't eat. It's a bad scene.

So if anybody reading this wants to help me get ahold of Mr. Zinke I can explain the preliminary steps in getting out of this ugly mess.

[crusty old prospector]

We’ve had several come through our place this year.

[ifinnegan]

Should have said equivalent to a human carrying an extra ten to twenty pounds.

[Deaf Smith]

Pretty cool they can track a butterfly as it is smashed on a windshield.

[CondoleezzaProtege]

I saw millions and millions of them once while driving home from work in Rancho Cordova California. An amazing site, right up there with seeing the Northern Lights.

Sounds breathtaking. 🥹

🐅🦋🌄

[TigersEye]

It is amazing that something so fragile can make a flight of thousands of miles.

[metmom]

We’ve got tons of milkweed growing on our property and when we weed whack and mow, we actually avoid them. They’re the only weed we let grow, cause of the monarchs.

[metmom]

I get a kick out of watching them fly.

They fly like Woodstock. While they may travel some few thousand miles as measured in a straight line, by the time they’re done flitting around apparently at random, they must cover 10 times that distance.

[Honorary Serb]

New!