Locusts Like It Cool

According to an article in New Scientist, global climate warming may actually suppress plagues of locusts. One less thing to worry about, eh?

Zhibin Zhang of the Chinese Academy of Sciences and colleagues have trawled through 1000 years of historical records documenting locust swarms and compared it with 1000 years of temperature, drought and flood data estimates.
image from wikipedia.

They found that the Oriental migratory locust (Locusta migratoria manilensis), which has been named as one of the most damaging agricultural pests in Chinese history, operates on a climate-driven cycle. Every 160 to 170 years, the swarms get bigger then subside again.

Counterintuitively, the timing of the largest swarms coincides with cooler periods.

"The popular view is that global warming may accelerate natural and biological disasters like drought and flood events, and outbreaks of pests, as predicted by the IPCC," says Zhang. "Our results suggest that warming reduced climatic extremes and locust plagues in ancient China."

That doesn't mean swarms won't happen. (Add this back to the list of things to worry about.) This month in Australia, drought followed by heavy rains in New South Wales has brought enormous swarms of locusts. One swarm is six kilometres long and 170 meters wide.

Here's a BBC video of the swarms. It's kind of like watching Hitchcock's "The Birds".