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Monarch butterfly populations in U.S. west are down an order of magnitude

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Re: Monarch butterfly populations in U.S. west are down an order of magnitude

#51

If you want to see where the Monarch butterflies migrate to in the winter and what such a thing looks like, there's a great reserve near the city of Angangueo, Mexico ( https://en.wikipedia.org/wiki/Angangueo ). 3.5hr bus ride from Mexico City. You get up in the morning and take a taxi higher into the mountains to the reserve, getting out and walking further up the mountain's roped off trail. The trail terminates int…

There's actually two different places where you can see them. There are that many living in central Mexico.

I agree, it was a really cool experience seeing them!

The craziest part is, we had to do some hiking to see them. I looked at my watch and it told me I was over 10,000 feet!

The tree line is higher in central Mexico than in northern North America. No wonder why I was so out of breath.

Re: Monarch butterfly populations in U.S. west are down an order of magnitude

#52
post #36

I'm no statistician, but the general trend seems to be upward for the last ten years. https://www.westernmonarchcount.org/wp-content/uploads/2018/... Indeed, but for some out-of-whack numbers in 1997, the data looks fairly non-hysteria-inducing. I wonder if anything was happening in the counties where the count took place this year that might have affected the 'volunteer citizen scientist' participation? Hmm... I see…

The general trend that goes upward in your graph isn't the number of butterflies, but the number of 'sites monitored', i.e., places where they searched for butterflies. In the time that monitored sites went from ~400,000 to ~1,400,000 the number of reported butterflies stayed roughly the same (~200,000), which should be grave cause for concern. The number of butterflies should be a linear correlation with the number…

>The general trend that goes upward in your graph isn't the number of butterflies, but the number of 'sites monitored', i.e., places where they searched for butterflies.

With all due respect, I can read a graph. I was referring to the total amount of butterflies. There is no data on the site to permit one to draw any correlation between the number of monitoring sites and the number of butterflies. We could add 10,000 additional monitoring sites in Antarctica and it would tell us nothing. There is no data to give any indication that ANYONE even was reporting at any particular site or how many were reporting.

In short, the organization's data is useless... at least the data easily available on their site. And, it's certainly insufficient to justify the handwringing in some of the comments.

Re: Monarch butterfly populations in U.S. west are down an order of magnitude

#53
post #39

This seems like part of the insect apocalypse story, and bee colony collapse disorder. All probably caused by overuse of insecticides. Note that if we don't find a way to correct this, it can be catastrophic on a timescale that makes the most alarmist climate change predictions seem like nothing. There must be some percentage of normal insect population density below which population of frogs and birds and what not w…

> All probably caused by overuse of insecticides. I am not aware of any scientific publication showing a causal link. Let's be a little careful about this. By increasing crop yields and reducing deaths from insect borne diseases, insecticides have greatly reduced human suffering over the past century. It's possible that insecticides are the cause, and if so, something has to be done, but such decisions need to be bas…

That reasoning is like, 70 years ago deciding smoking is fine because there are few and conflicting scientific studies that conclude no, smoking does not have serious impacts on health.

Insect deaths are acutely reported in the last decade.

Re: Monarch butterfly populations in U.S. west are down an order of magnitude

#54
post #39

Earlier quoted context omitted.

> All probably caused by overuse of insecticides. I am not aware of any scientific publication showing a causal link. Let's be a little careful about this. By increasing crop yields and reducing deaths from insect borne diseases, insecticides have greatly reduced human suffering over the past century. It's possible that insecticides are the cause, and if so, something has to be done, but such decisions need to be bas…

Yeah, but think about it: insect population is down? why keep using pesticides at the same level as usual?? And if you reduce pesticide use because there's fewer insects, and if the insect population recovers, then you'll have some very suggestive evidence (still not dispositive, but so what). There's a hypothesis to test, so let's test it.

Here are some possible answers to your "why??"

Insect population may be down overall, but not down with crop pests.

Insecticides may require a certain density of use to be effective; that is, there may be a non-linear dose/response curve such that it's not really meaningful to reduce the current levels.

The goal is to maximize income. Reduced insecticide use, even with the relatively low corresponding insect populations, might still reduce the yield and/or quality and therefore profit. Think of how the oceans are overfished, but while there's a good reason that everyone should greatly reduce their catch, there's no good reason for any one fishing crew to do that on their own.

Re: Monarch butterfly populations in U.S. west are down an order of magnitude

#55
post #28

As I believe that Earth is the only life-bearing planet in our galaxy, if not the whole Universe, I'm extremely saddened with news like this of a near-extinction of yet another fascinating species. My only hope is that humanity will spread among the stars, dispersing what species remain to billions of new worlds, and that this might be our redemption for the unspeakable crimes we have committed against life...

I hope it doesn't happen but if earth becomes inhospitable to mankind and we all die it won't be the end of "life".

Earth had mass extinction events where 90%+ of living things died, and life just came up with some new stuff and recovered.

Re: Monarch butterfly populations in U.S. west are down an order of magnitude

#58
post #50
post #39

Earlier quoted context omitted.

> All probably caused by overuse of insecticides. I am not aware of any scientific publication showing a causal link. Let's be a little careful about this. By increasing crop yields and reducing deaths from insect borne diseases, insecticides have greatly reduced human suffering over the past century. It's possible that insecticides are the cause, and if so, something has to be done, but such decisions need to be bas…

Ironclad facts, science, studies, & research are great. However, if we are facing imminent collapse of pollinator populations (which would lead to a lot of human suffering) the precautionary principal starts to look interesting. In other words, if we run the risk of population collapse within ten years, and population collapse will lead to crop failure and mass starvation & death, but rigorous studies on cause will t…

For the most part, our calorie crops do not rely on insects.

For example, corn is wind pollinated and wheat, soy, rice and potatoes are self pollinating.

Having reduced access to things like almonds and apples is gonna suck, but even with 0 insects it's still going to be reduced access, as hand pollination is quite a fast process.

Re: Monarch butterfly populations in U.S. west are down an order of magnitude

#59
Tangential: helping insects.

I could obtain free wildflower seeds from a Dutch foundation aiming to protect the bees, and last Spring I did some 'guerilla sowing' on bare patches of land waiting for new building construction.

Big success. The nutrition-poor soil apparently was ideal, and in places dense flower beds appeared. It gave me huge satisfaction to not only see bees and other insects, but tourists and inhabitants making photographs, and children shouting excitingly "Look at all these flowers, mom!". A true win-win for humans and bees.

Would be really easy for the municipality to adopt this as a policy and sow all these temporary spots with flowers.

Re: Monarch butterfly populations in U.S. west are down an order of magnitude

#60
post #12

Earlier quoted context omitted.

You're assuming that's just due to insecticides. Insects are exposed to multiple stressors. One of them also happens to be global warming. Others are habitat loss, insecticides, invasive species, etc. In fact the researchers measuring the loss of insect biomass in puerto rico rainforests attributed it primarily to climate change since the other factors do not apply there.

The variations in surface temperature we have seen in the modern era are nothing compared to what we've seen in the recent geological record. Moreover, insects are very sturdy throughout the geological record, so it's very difficult to believe that less than 1C change in a century could cause this (the end of the last glacial period saw a 7C swing in just a few hundred years). It's pretty clear that climate change is…

> it's an extremely complex system about we have shockingly little information in the grand scheme of things (30 years' worth of satellite data!),

You should stop making that argument as it's too much like a well-refuted talking point that climate change denialists use.

We have many different lines of evidence. “Global Warming in an Independent Record of the Past 130 Years“, for example, shows that the temperature changes are consistent across 173 different types of records, from measured temperatures to grape harvest to oxygen isotope ratios.

> "recent climate change is minute even by standards of the past two millennia"

How do you make this claim if you think we don't have good global temperature measurements more than a few decades old?

The only arguments I can easily find in support of this claim are by climate denialists who use one temperature series from Greenland. (There may be more, but that's the one that keeps popping up in my searches.)

While those who use a larger set of temperatures, to give a better sense of global temperature change, show that the recent temperature change is not "minute", like the one https://skepticalscience.com/medieval-warm-period.htm from Moberg et al. (2005) titled "Northern Hemisphere Temperature Reconstruction" for the last 2,000 years.

> Willis Eschenbach

And we should trust his work because .... why?

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