Monarch numbers appear to be up

Despite signs of improvement, they could be added to endangered species list
Although it’s still too early to know how many monarch butterflies made the annual migration this year from the United States and Canada, the U.S. Fish and Wildlife Service has decided to go ahead and determine if the insect should be classified as an endangered species.
The director of Mexico’s Monarch Butterfly Biosphere Reserve says the numbers appear to be up this year, although an official census won’t be ready until the middle of this month. “We’re encouraged because we’ve seen more,” Gloria Talavera told the Associated Press on Monday.
But just as the greater numbers show up, another threat comes along: unusual cold temperatures pose another threat to the monarch. The National Meteorological Service has forecast 55 cold fronts until May, up 15% from the average.
The butterflies appear to be aware of the forecast, or have their own system of predicting the weather. Talavera said they are looking for more protected areas, such as canyons, perhaps as a measure to protect themselves from the cold. They also arrived later than normal.
The numbers of monarchs have been down significantly in recent years, a decline that has been attributed to habitat loss through logging in Mexico and fewer milkweed plants, on which the butterflies lay their eggs. University of Chicago ecologist Marcus Kronforst estimates that 1 billion made the Mexico migration in 1996, but barely 35 million did so last year.
The insects are counted by estimating the number of acres they occupy, which was only 0.67 hectares last year. The highest since recording began in 1993 was 18.2 hectares in 1997-97.
Their winter territory in Mexico is found in the State of Mexico and Michoacán, where the butterfly reserve is located.