Monarch butterfly population critically low on California coast – again

Study finds 29,000 butterflies, compared with 4.5 million during the 1980s, as experts point to habitat destruction

Thu 23 Jan 2020 02.03 GMT

The western monarch butterfly population wintering along California’s coast remains critically low for the second year in a row, a count by an environmental group released Thursday showed.

The count of the orange-and-black insects by the Xerces Society, a not-for-profit environmental organization that focuses on the conservation of invertebrates, recorded about 29,000 butterflies in its annual survey. That’s not much different than last year’s tally, when an all-time low 27,000 monarchs were counted.

“We had hoped that the western monarch population would have rebounded at least modestly, but unfortunately it has not,” said Emma Pelton, a monarch conservation expert with the Xerces Society.

By comparison, about 4.5 million monarch butterflies wintered in forested groves along the California coast in the 1980s. Scientists say the butterflies are at critically low levels in the Western US due to the destruction of their milkweed habitat along their migratory route as housing expands into their territory and use of pesticides and herbicides increases.

Continued