03:03 - Source: CNN
The unusual migration of monarch butterflies
CNN  — 

The body of a second butterfly conservationist and activist has been found in Mexico, authorities said.

Raúl Hernández Romero, a part-time guide and conservationist at Mexico’s largest monarch butterfly reserve, was discovered dead Friday in the Mexican state of Michoacán, local authorities said in a statement released Saturday.

He was found with “blunt blows on different parts of the body and a head injury, caused by a sharp object,” the statement said.

Romero was reported missing by relatives hours before his body was found. His wife said he was last seen January 27 leaving his home in San Pedro Libertad, according to officials.

He is the second butterfly activist to be found dead in less than a week.

The body of Homero Gomez Gonzalez was found Friday in a retention pond, also in Ocampo. He also had a head injury and died of drowning, authorities said. He had been missing since January 13.

Gomez, known as the Defender of the Monarch Butterfly, might have come into conflict with illegal loggers while carrying out his conservation work, Mexico’s State Commission for Human Rights said.

Michoacán state is home to the Monarch Butterfly Biosphere Reserve, a UNESCO World Heritage Site in a forested area about 100 kilometers (62 miles) outside Mexico City. Every autumn, as many as a billion monarch butterflies migrate to the site from as far north as Canada as part of an eight-month migration cycle.

But the reserve’s forest is threatened by illegal logging and human encroachment. In 2015, UNESCO proposed a draft decision that expressed the “utmost concern” over the reported decline of the butterfly’s overwintering population.

The sheer mass of butterflies in the area cover trees like leaves, weigh down tree branches and create a sound similar to light rain with the beating of their wings, UNESCO notes.

Because of the monarch’s short life span, four successive generations of monarchs are born and die over the course of the complete migration. Yet somehow they return to the same areas every year, making it one of the great unexplained phenomena of the natural world.

CNN en Español’s Fidel Gutierrez and CNN’s Eric Levenson contributed to this report.