Monarch butterflies, which have recently been facing severe habitat loss in the United States, are slowly making a comeback, showing conservationists that they are down, but not out.
Amazingly, the number of monarchs that made it to their wintering grounds in Mexico has rebounded 69 percent from last year's record-low levels. The fluttering insects covered 2.79 acres (1.13 hectares), up from only 1.65 acres (0.67 hectares) last year, according to a census released Tuesday by Mexican authorities.
However, the World Wildlife Fund (WWF) is quick to point out that their numbers are still incredibly low compared to what they once were, and monarch butterflies are not yet in the clear.
"Of course it is good news that the forest area occupied by monarchs this season increased," Omar Vidal, head of the WWF in Mexico, told The Associated Press (AP). "But lets be crystal clear, 1.13 hectares is very, very low, and it is still the second-smallest forest surface occupied by this butterfly in 22 years of monitoring."
Each year, as the last autumn leaves fall, million of monarchs in the northeastern United States and Canada migrate a stunning 2,500 miles to their wintering habitat in Mexico. But as intensive logging activity destroys crucial fir tree forests, far fewer butterflies have been seen making the trip.
In fact, the US Fish and Wildlife Service (FWS) reported in December that the butterflies had declined by a whopping 90 percent over the past 20 years, prompting talks of granting them federal protections under the Endangered Species Act.
But regrettably, illegal logging in Mexico is not the only threat to these beautiful black-and-orange butterflies. Climate change and loss of milkweed- the main food source for monarch larvae - in the United States are causing their numbers to decrease as well. (Scroll to read on...)
Use of herbicides, or chemicals sprayed on genetically modified crops such as corn and soybeans, are mostly to blame for the latter. In the last 20 years, these orange and black butterflies have lost more than 165 million acres of vital habitat once overflowing with milkweed plants - an area about the size of Texas.
"The question we should all be asking now," Vidal told the AP, is whether the United States can halt the loss of milkweed habitat.
Authorities are even turning to backyard gardeners for help, asking them to plant native milkweeds. Unfortunately, these good intentions have gone awry, inadvertently trapping and exposing these near-endangered insects to harmful parasites when gardeners began planting the wrong kind.
With logging, milkweed loss, climate change and parasites to worry about, it's a wonder monarch butterflies even managed to bounce back this year. But they've done it before.
In 2001, rain and freezing temperatures causes populations to plummet, only to double in number the following year, to scientists' amazement. Then in 2004, unfavorable weather, pollution and deforestation caused another drastic decline in the population, but the next year, the butterflies rebounded.
Now it seems that monarchs are partially recovering yet again, although overall the species is in decline.
Two decades ago it would have seemed highly unlikely that North America's monarchs would be endangered, given that one billion of these butterflies were flittering across the country in the mid-1990s. But as of last winter there are only 35 million left, the lowest their population has ever been.
Even with this partial population spike, Lincoln Brower, a leading entomologist at Sweet Briar College in Virginia, has told the AP that with anything below 2 hectares (4.1 acres), "they will remain in the danger category and I will continue to be concerned. "
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