Monarch Butterfly Numbers are Soaring this Year

After several years of declining monarch numbers, researchers believe this year will see a dramatic uptick in monarch butterflies making their way across states like Texas,

Craig Wilson, of the USDA Future Scientists Program, says that early data shows monarchs are bucking a severe downward trend of the past several years and, for this year at least, showing strong numbers.

“Figures show the highest number of hectares covered since at least 2006,” Wilson said in a press release. “Monarch numbers are usually measured in hectares, so that’s means about 15 acres are being used for their breeding grounds in northern Mexico. That’s a really positive sign, especially since their numbers have been down in recent years.  I believe the record low was in 2013-14 when only 0.65 hectares (about 1.65 acres) were covered. So it is very promising news.”

Texas is a key spot for monarch butterflies on their annual migration north to lay their eggs. It is one of the major calling points where they gather their energy for the next phase of their long, multi-generational flight that will ultimately take them to across the Canadian border. Seeing such strong numbers at this point in the migration from Mexico would suggest that, if the weather remains good and no pathogens claim vast swathes of the butterflies, the year’s migration could be a much-needed boost to the monarchs and to wider butterfly numbers.

Butterfly numbers in decline

Globally, we know insect numbers are falling dramatically, even compared to just a few decades ago. On the whole, butterfly numbers appear to be going the same way. In North America, monarch butterflies are down 80 percent since the mid-1990s, with declines even more pronounced when we break down the monarchs into their contingent migration groups.

For example, the smaller of the two migrations, which flies through California, saw its numbers plummet last year by 86 percent, with some figures suggesting its numbers may now be as low as 20,000 individuals. This is particularly disturbing, because a healthy population benchmark would be over 30,000 individuals, minimum.

This year has seen California skies filled with a surprisingly large migration of painted lady butterflies, who look similar to monarchs but are distinguishable by their size and different markings. As always, that population numbers can differ from year to year, but the wider decline of butterflies is considered a fact at this point.

That’s why the news that monarch numbers in Texas are looking good at this stage of the migration is so important. A healthy monarch population could signal that things are on the up for monarchs as a whole in North America and places like the UK—but obviously it’s important we not get ahead of ourselves.

Monarchs Still Face Roadblocks

Other US researchers have confirmed this is likely to be one of the biggest migrations of monarch butterflies in years, but they sound a note of caution. They’d prefer that the monarchs stay in Texas a little longer rather than flying on to pastures new. Why? It all comes down to milkweed.

The butterflies actually got to Texas slightly ahead of the milkweed this year, and that could have curtailed their numbers. Fortunately, they seem to be doing well, but it would be ideal if they stayed in Texas and South Oklahoma for a little longer and laid their eggs there. This would benefit them in by ensuring that they have left their eggs in warming areas where they are likely to have the best chance of developing fast and giving the milkweed on the trail ahead of them time to develop and open.

Researchers have been quick to point out that factors that have contributed to insect decline and the monarchs’ overall population issues haven’t gone away.

Homogenization of habitat, land clearing and pesticide use have all been blamed for plummeting insect numbers, and they are still pressing issues. This boost may not be replicated next year, but the good news here is there’s something we can all do to help monarch butterflies capitalize on this good fortune: cultivate milkweed in our own gardens. These inexpensive plants help support not just this generation of monarchs but monarchs for many years to come and help reinvigorate their numbers as a result of this unexpected but very welcome upturn in the population.

Photo credit: Getty Images.

71 comments

Virgene L
Virgene L9 days ago

Wonderful news! Keep up the good work. Thanks Barb!

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Leopold Marek
Leopold Marek23 days ago

:-)

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sandy Gardner
sandy Gardner24 days ago

Finally...some good news!

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Marge M
Marge M24 days ago

I love butterflies!!

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Bonnie Lynn M
Bonnie Lynn M24 days ago

Thank you

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sandra m
sandra m25 days ago

we have milkweeds growing all over in our yard. we sent off 100 monarchs last summer.

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Glennis W
Glennis W25 days ago

Awesome Thank you for caring and sharing

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Glennis W
Glennis W25 days ago

Thank you for caring and sharing

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Glennis W
Glennis W25 days ago

Wonderful Thank you for caring and sharing

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Glennis W
Glennis W25 days ago

Thank you for caring and sharing

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