What Santa Monica can do about monarch butterfly decline
In 1997 there were more than 1.2 million monarchs overwintering in California and in 2014 only 234,000 – an 81 percent decline from the 1997 high, 48 percent decline from the 18- year average, and just over 10 percent per year. What has caused such a decline?
The Xerces Society for Invertebrate Conservation, which studies and tracks the monarch populations has several theories; the loss of milkweed breeding habitat, herbicides and pesticides, GMO herbicide resistant crops, development and logging at their over wintering sites, climate change, and extreme weather, such as the multi-year drought California has been experiencing.
The herbicide glyphosate, know commonly as Monsanto’s Round Up, used in both commercial agriculture and in backyard gardening, has lead to the decline of milkweed plants. Neonicotinoids (a class of neuro-active insecticides chemically similar to nicotine), which began to be widely used commercially in the 1990’s, are also a factor in the decline of the butterflies. Neonicotinoids have been found in soil and can be taken up into the plant, and are lethal to monarchs.
Read full article here: http://smdp.com/what-santa-monica-can-do-about-monarch-butterfly-decline/155656
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