Lincoln Brower, monarch butterfly expert, at 86

Lincoln Brower, who was considered one of the foremost experts on the iconic monarch butterfly and a scientist who advocated for protection for the declining species, has died. He was 86.

Linda Fink, his wife, confirmed Friday that Mr. Brower died July 17 at home in Nelson County, Va., after a long illness.

Mr. Brower studied the orange-and-black-winged insect for more than six decades. It is famous for its epic migration each year.

“What attracted Lincoln is they’re so incredibly interesting,” said Karen Oberhauser, a monarch expert and director of the University of Wisconsin-Madison Arboretum.

Light as a paper clip, the butterflies migrate like birds or whales. Most travel 2,000-plus miles from various states in the U.S. and Canada to the mountains of Mexico. A much smaller number goes to the California coast.

In those places, the winter climate typically doesn’t freeze them. But it’s cool enough that the insects maintain their fat preserves to begin their return.

It’s a multigenerational journey north as the butterflies and their offspring feed off milkweed. Eventually, the cycle starts anew.

Mr. Brower spent a lot of time in Mexico, where massive clusters of monarchs hang like Spanish moss in fir forests.

“Just imagine a place where there are a hundred million of whatever you were studying hanging from the trees,” said Mr. Brower’s son, Andrew Brower, who studies butterflies and is a biology professor at Middle Tennessee State University.

Mr. Brower also charted the butterflies’ stark decline. Its overall population has fallen by about 80 percent over the past two decades, according to the Center for Biological Diversity, a conservation group.

Herbicide use, logging and severe weather events have all threatened the butterfly. In 2002, freezing temperatures and rain led to a massive die-off in Mexico.

“Sticking my hand to gently pull out the beautiful delicate creatures I’ve worked with for 25 years, there was an almost overwhelming feeling of sadness,” Mr. Brower told The Associated Press.