Drought clips butterfly population
One of the sure signs of warmer months to come — monarch butterflies — might be harder to find this year, according to butterfly tracker Craig Wilson, a senior research associate at Texas A&M University.
In fact, 2014 may go down as one of their worst years ever because of several issues now occurring in Texas, Wilson said.
The colorful insects are under stress because of ongoing drought, an unusually cold winter and a lack of milkweed, their primary food source.
“Unfortunately, the harsh and lingering cold conditions mean that the milkweed plants that monarch caterpillars must have to live have yet to start growing, and these are the only plants on which they can lay eggs to provide food for their caterpillars,” he said.
Each March and April, the monarchs flap their way from Mexico north into the USA and Canada, stopping in Texas along the way to munch the milkweed. No single butterfly finishes the journey; it takes a few generations to complete the trip.
In the summer, breeding monarchs live only about 2-5 weeks.
“The severe drought in Texas and much of the Southwest continues to wreak havoc with the number of monarchs,” Wilson explained. Butterfly wintering sites in the Mexican state of Michoacán are at near-historic lows, he added.
Earlier this year, the butterflies were clustered on only 1.7 acres in Mexico. This compares with an average of around 15 acres in the mid-1990s. “The conditions have been dry both here and in Mexico in recent years,” he said.
Wilson said there should be a national effort to save the mon- archs or their declining numbers will reach the critical stage.
“We need a national priority of planting milkweed to assure that this magical migration of monarchs will continue for future generations,” he said.
“If we could get several states to collaborate, we might be able to promote a program where the north-south interstates were planted with milkweed,” Wilson said. “This would provide a ‘feeding ’ corridor right up to Canada for the monarchs.”