Five rare Monarch butterfly sightings have been reported on the south coast of England, where they are believed to have blown from across the Atlantic on their epic annual journey across North America.

Martin Warren, chief executive of Butterfly Conservation, confirmed the sightings in a tweet on Wednesday,The Guardian reported.

While the report count is up to five, "summer sightings [of Monarch butterflies] are more likely illegal releases," Warren wrote in the tweet.

Conservationists believe the butterflies were swept over the Atlantic during their yearly journey across the North American continent to Mexico or California.

"At this time of year, coinciding with the big migration across North America, you have ex-hurricanes and storm fronts sweeping across the North Atlantic," said Richard Fox, surveys manager at the charity, as quoted by The Guardian. "Monarchs' arrival has sometimes in the past coincided with the arrival of North American songbirds and dragonflies."

Known for their ability to weather long journeys, the butterflies likely were helped by warmer weather in September, something that can bring an influx of insects into England.

 "It is unusual," Fox said. "It makes you wonder whether something is about to happen, whether it is the start of something big."

A coalition of U.S. groups recently filed a petition to ask that the Monarch butterfly be protected under the Endangered Species Act.

The environmental and food safety groups that have made the request say that the monarch butterfly's population in the U.S. fell last year to 90 percent below its 20-year average, the St. Louis Post-Dispatch reported last month.

The species is under threat after milkweed in the Midwest has greatly diminished, taking away the monarch's source of food in the area where most of the butterflies are born, according to the coalition.

The Center for Biological Diversity and the Center for Food Safety filed the request as co-lead petitioners on Aug. 26 and were joined by the Xerces Society.

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