Habitat loss on breeding grounds cause of monarch decline, study finds
Thursday, June 5, 2014 - 11:52
in Biology & Nature
Habitat loss on breeding grounds in the United States -- not on wintering grounds in Mexico -- is the main cause of recent and projected population declines of migratory monarch butterflies in eastern North America, according to new research. Milkweed is the only group of plants that monarch caterpillars feed upon before they develop into butterflies. Industrial farming contributed to a 21-per-cent decline in milkweed plants between 1995 and 2013, and much of this loss occurred in the central breeding region.