GAINESVILLE, Fla. — The Florida monarch butterfly population in North Central Florida has declined by 80 percent since 2005, according to research by the University of Florida.

  • Fla. monarch butterfly population has been declining since 1985
  • Researchers: Decline could be due to shrinking milkweed populations
  • LINK: Read the full study

The 37-year survey released this week says the caterpillars and butterflies in North Central Florida have been declining since 1985, and have been substantially declining over the last decade.  

According to researchers, they believe a possible culprit behind the decline is shrinking milkweed populations due to the increasing use of glyphosate -- a herbicide used to eliminate weeds that's lethal to Milkweed.

Co-author of the study Ernest Williams says a decline in milkweed means a decline in available habitat for the monarch butterflies.

A news release from the Florida Museum of Natural History says the butterflies lay hundreds of eggs on milkweed over their six to eight week lifespan.

Researcher Jaret Daniels says Florida is a staging ground of sorts for the recolonization of butterflies on the U.S. East Coast.

The Associated Press contributed to this report.