A monarch butterfly takes off from a tree trunk in the winter nesting grounds of El Rosario Sanctuary, near Ocampo, Michoacan state, Mexico, Friday, Jan. 31, 2020. Hundreds of farmers and agricultural workers attended the funeral of Homero Gomez Gonzalez on Friday, and the homage to the anti-logging activist was like a tribute to the monarch butterfly he so staunchly defended. Credit: Rebecca Blackwell | AP

MEXICO CITY — Mexico’s forests this winter received 53 percent fewer monarch butterflies, a species that migrates south from Canada and the United States, according to figures published this week.

Environmental organization World Wildlife Federation said that in the November-to-March season, monarch butterflies occupied 2.83 hectares of forests in the states of Michoacan and Mexico, as opposed to the 6.05 hectares they occupied in the 2018-19 season.

The drop is “not alarming” because the presence of butterflies in the previous season had been atypically high, “but we must remain vigilant so that it does not become a trend in the coming years,” said Jorge Rickards, Director General of WWF Mexico.

WWF partly attributed the drop to lower temperatures in Texas, a breeding site, causing “slower growth of eggs and larvae in the spring” and subsequently reducing the monarch butterfly population and the number that was able to migrate.

Earlier this year, two activists protecting the monarch butterfly from the dual threat of climate change and illegal deforestation — Homer Gomez and Raul Hernandez — were reportedly found murdered within the space of a week.

The drug cartels that dominate the state are involved in a range of criminal enterprises, including illegal logging of protected firs, hardwoods and pines.