The number of monarchs wintering in California has dropped to a five-year low, despite more volunteers counting more sites in search of the orange-and-black insect that is arguably the most admired of North American butterflies, a report said on Friday. The latest tally of 200,000 monarchs in forested groves in California’s central coast has dropped from the 1.2 million counted two decades ago, indicating the number of butterflies found west of the Rocky Mountains, or the so-called western population, continues to sharply decline, the Xerces Society for Invertebrate Conservation said in a report. “It’s certainly concerning,” said Sarina Jepsen, endangered species program director for the Xerces Society.
Western monarchs are born on milkweed plants in such states as Arizona, Idaho, Utah and Washington before embarking on a seasonal migration to California. The annual count in California, done at the end of autumn by dozens of volunteers and scientists, last saw a severe low in 2012, with 144,812 butterflies across 136 sites, she said. In another troubling trend, the 200,000 butterflies found in the 2017 survey stemmed from monitoring of 262 sites, which were even more sites than were tracked the previous year when 300,000 monarchs were counted, Jepsen said.
Source: Reuters, Feb 3, 2018
https://www.reuters.com/article/us-california-butterflies/count-marks-s…
- Login om te reageren