Decline in Moth Populations Observed Across Southern US Cities

Insects of all stripes are in the midst of a vanishing act, a catastrophic sleight-of-hand occurring so rapidly that scientists can’t keep up. Things get even trickier when you consider that insects have a complex life cycle with eggs, larvae, pupae and adults. Are they all disappearing at equal rates, or are some faster than others? Few people have checked.

In a new study, researchers presented the results of a year-long survey in which they monitored the abundance of adult and larval moths in an urban, sub-tropical environment. It’s the first time researchers have analyzed multiple life stages to assess the severity of ongoing insect declines. It’s also one of only a few studies that have tackled the problem in lower latitudes, where extreme temperatures are pushing animals to their limit.

“Subtropical and tropical environments have the greatest insect abundance and diversity and are areas seeing the greatest expansion of cities worldwide,” said lead author Michael Belitz, who conducted the research while working at the Florida Museum of Natural History. “The urban heat island effect in these areas may be especially detrimental to insects.”