TE24 Sci &Tech Desk:
The migrating monarch butterfly, which has turned North American forests into a kaleidoscope of color for millennia in one of nature’s most spectacular mass migrations, is at risk of extinction, international conservationists said Wednesday.
The butterfly population, numbering in the millions, has declined by more than 85 percent since the 1990s, scientists estimate. On Wednesday, it was placed on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. University of Wisconsin-Madison Arboretum.
Logging has destroyed many of the insects’ wintering grounds, agricultural pesticides are destroying the milkweeds that feed their caterpillars, and extreme temperatures caused by climate change are forcing them to migrate too soon before they can use up the remaining milkweed.
Overall, more than 41,000 species are threatened with extinction, according to the IUCN, in what scientists call the planet’s sixth mass extinction and the first caused by humans. IUCN Director General Bruno Oberle.
Joining the migrating monarchs on Wednesday’s list are the remaining species of sturgeon – huge prehistoric fish that have been found in Eurasia and North America for centuries for their meat and caviar.
Of the 26 sturgeon species, 17 are now considered critically endangered, the IUCN says. “There’s something to be said about humanity when a species that survived the dinosaurs is being pushed to the brink of extinction by humans,” said Ms Beate Striebel-Graeter, head of the World Sturgeon Initiative Wildlife Fund. .
The red list update has given a glimmer of hope. Tiger numbers have increased by 40 percent since the last assessment in 2015, thanks to improved monitoring, to 5,578 in the wild. But some big cat biologists have questioned how the numbers are calculated, saying such increases are misleading.
