MacMusic  |  PcMusic  |  440 Software  |  440 Forums  |  440TV  |  Zicos
monarch
Recherche

Monarch Butterfly Populations In the West Are Down an Order of Magnitude

dimanche 2 décembre 2018, 16:15 , par Slashdot
An anonymous reader quotes a report from Quartz: Far fewer [monarch butterflies] were heading south this year, and those that have arrived did so a month late, according to Xeres, a non-profit conservation group for invertebrates. One researcher said it was the fewest monarch butterflies in central California in 46 years. Surveyors at 97 sites found only 20,456 monarchs compared to 148,000 at the same sites last year, an 86% decline. It's possible more insects will make the journey late this year, says Xeres, but that now seems unlikely. The minimum population size before the species experiences 'migration collapse' is unknown, but a 2017 modeling paper in Biological Conservation (pdf) found that 30,000 butterflies adult butterflies are probably the smallest viable population. Without this critical mass, there aren't enough insects in the western monarch population to continue one of the world's most remarkable lifecycles.

Read more of this story at Slashdot.
rss.slashdot.org/~r/Slashdot/slashdot/~3/xGm23TIVPvY/monarch-butterfly-populations-in-the-west-are-d...
News copyright owned by their original publishers | Copyright © 2004 - 2024 Zicos / 440Network
Date Actuelle
jeu. 28 mars - 10:15 CET