Effect of climate change on butterfly migration?

When I was reading of monarch migration I wonder how the climate change affects butterfly migration not just monarch but every butterfly that perform migration? You know butterfly are most adaptive insect, they change their habitat as soon as there is a change in environment .
Will they survive climate change?[ If you ever seen Butterfly migration with your naked eye feel free to share your experience]

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Not just butterflies. Some dragonfly species make long migrations, indeed, the longest insect migration known is a dragonfly migration between India and Africa, and even in North America some dragonfly migrations are of a comparable length to those of the Monarch Butterflies

In California Convergent Ladybugs that live away from the coast migrate from the lowlands up into the mountains.

Many other insects/flying arthropods, make migrations of greater or lesser lengths.

As with many climate sensitive organisms now especially ones that move between habitats there are several factors at play. The most obvious two are the magnitude of change and the rate at which it happens. We’ve had bigger changes in the past, but they’ve happened slower. Imagine a car going 120 mph and hitting the brakes in an open road, no problem, now imagine a car going 60 mph and hitting a brick wall… big problem; they both stop, one from a much greater speed, but rate of change is slower for that one os no issues in adjusting to the change, which is not the case with the slower moving but more rapidly changing one. Right now we are making a large change very rapidly and a very real concern is that organisms can’t adapt quickly enough.

The other issues that aren’t talked about enough outside of academic and professional circles are migration triggers and habitat changes at either end of the migration, as well as between.

Here’s an example from the real world to help illustrate: a bird species spends the non-reproductive time in a mild climate, and is triggered to start its migration by changes in light due to the Earth’s orbit. Normally this means that they head to X location (often northern areas) just in time for the emergence of vast numbers insects to hatch. They gorge themselves on these, lay eggs, feed their young on them, and by the time the insect boom is over the young are ready to migrate back to the mild climate area.

However, the insect emergence is not triggered by light, but by temperature, and with a warming world they emerge before the birds arrive. This means that the birds arrive and don’t have enough feeding time to raise their young and population numbers drop as a result. This is something that is happening right now.

Now take that a step further. One of the issues with climate change is climate variability. Let’s say that said food insect hatches early due to a few hot days, then there is a cold spell (Finland had just this exact thing happen recently, an New England has had this happen a few times in recent years). The hatched insects die due to the cold. When the birds arrive there is no food, and after such a long migration they desperately need that food. Without it they might not even be able to make the flight back, and they certainly can’t breed successfully.

What this means is that even if a particular species can actually manage to adjust to climate change if something they rely on can’t adjust then both (and more) can go extinct.

An example of this is that in north America (and Australia) dung beetles are imported to deal with agricultural animal feces. Dung beetle species specialize in different types of dung, and when the megafauna went extinct the animals that relied on them to survive also went extinct (certain species of dung beetles, Teratornis, large carnivores, etc.

With Monarch butterflies one of the biggest threats to the species is their winter habitat in Mexico, both for the climate aspect, as as a result of logging activities that destroy the very small area of critical habitat.

Monarch have weathered past climate changes, although none taking place so quickly, but now they face an additional, and potentially larger, danger that a critical habitat for the species is being destroyed both via climate change and direct logging. Even without climate change they might not survive human greed.

And yes, having lived in Coastal California for many years I’ve had the good fortune to see Monarch migrations first hand often. Seeing a grove of trees with their trunks completely covered in a blanket of fluttery orange wings is pretty amazing.

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I’ve always lived near a few Monarch overwintering sites. In the 1950s and 60s, these special groves of trees in Santa Cruz and Monterey had hundreds of thousands of Monarchs in the winter. They covered the host trees so thickly the tree was not visible at all unless it warmed up over 70 F, then they would alight into the sunshine and fill the air. These very same groves now may see less than a thousand butterflies. One sanctuary I visited in Monterey last winter had NOT ONE. :sob:.

Once or twice, I asked the rangers if the butterflies had started using different groves than the ones I was used to visiting. Apparently, not. The rangers have suggested pesticide use, habitat loss along the migration route, and climate change as reasons for the steep decline.

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Also a smaller issue around well meaning gardeners planting the wrong (local) species of milkweed to support migrating monarchs. Gardeners and nurseries lean to human eye candy. The committed few choose to get the right species for where their garden is on the route.

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I went to UCSC back in the early 90s for undergrad and we still had decent monarch sites back then. Not as good as in the previous two decades, but I would walk down from where I lived at the time to Natural Bridges State Beach, past the Wrigley’s factory that always smelled of peppermint, and down to the eucalyptus groves that the monarchs rested in. Made for peaceful afternoons after morning classes.

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I’ve visited that same grove many times, too, and it is still peaceful and lovely. Most of my monarch observations come from there: Monarchs
If I recall correctly, last year I think they got about 900 butterflies. There is another grove over by the surfer’s lighthouse that gets monarchs, but I did not ask about the numbers.

Ps… I remember the Wrigles gum plant and the smell, too. But, it has been gone for a while.

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900? That’s an appalling tiny amount. Even in the 90s that would have been just a part of 1 trunk out of 10-15 trunks (and sometimes far more) and those were far smaller collections than used to be the case.

Wish I had taken photos of them back then.

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And sadly there are many other butterfly species which are not in the view of us .We do not have even data of there population and much more. I think they are facing silent death or extinction. We will not know what happen to them for us they will just be disappeared. That’s why I think we should have conservation data and quality research done for every single species of not just butterflies but other animals also. That’s the same thing happened to vaquita, and sadly they are beyond our saving , Slowly going to silent death.

You know there are many species of butterflies and ladybirds that disappeared from my area and when I search of them on internet they always seem to be in category of “Least Concern”. Are they really “least concern” or just they seems to be?

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Yeah! I remember my dad took home movies of the monarch trees in the sixties. But, even if one of us kids still has the old reels in an attic or garage, I doubt they would be viewable now. :confused:

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Well, i guess those old pinned museum collections could prove useful in the future. Here’s hoping they don’t all get thrown out.

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I think this is also a problem with availability. People want to plant milkweed to support monarchs, so they go to the nearest nursery, not knowing the different species of milkweed, and end up buying tropical milkweed because that’s all that’s available. I have yet to find a nursery within 30 miles of me that actually carries the native (Los Angeles County) narrowleaf milkweed. I’ve even seen some nurseries that have tropical milkweed in their “native” sections.

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Yes, it’s hard-to-impossible to find native milkweed for sale. Through the Calif. Native Plant Society, I found a seller or two of milkweed seeds ‘suitable for your county’, but those were hideously expensive.

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Your university library may have archived equipment.
Or the movies could perhaps be converted to digital?

I think the problem with the wrong milkweed species, is that it blooms at the wrong time?

I have a habit if nagging/lecturing local nursery staff about having the wrong milkweed. There is no excuse for it around here, as there are at least five California native plant wholesalers within 100 miles. I’ve had some luck at the locally-owned nurseries. No luck at all with the big box stores. Support your local nurseries!!!

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Barbara Kingsolver explored this “what-if” in her novel, Flight Behavior.

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