Global warming is mixing up nature's dinner time, study says

April 16, 2018 by Seth Borenstein

Global warming is screwing up nature's intricately timed dinner hour, often making hungry critters and those on the menu show up at much different times, a new study shows.

Timing is everything in nature. Bees have to be around and flowers have to bloom at the same time for pollination to work, and hawks need to migrate at the same time as their prey. In many cases, global warming is interfering with that timing, scientists said.

A first-of-its-kind global mega analysis on the biological timing of 88 species that rely on another life form shows that on average species are moving out of sync by about six days a decade, although some pairs are actually moving closer together.

While other studies have looked at individual pairs of species and how warming temperatures have changed their migration, breeding and other timing, the study in Monday's Proceedings of the National Academy of Sciences gives the first global look at a worsening timing problem.

These changes in species timing are considerably greater than they were before the 1980s, the study said.

"There isn't really any clear indication that it is going to slow down or stop in the near future," said study lead author Heather Kharouba, an ecologist at the University of Ottawa.

For example in the Netherlands, the Eurasian sparrow hawk has been late for dinner because its prey, the blue tit, has—over 16 years—arrived almost six days earlier than the hawk.

It's most noticeable and crucial in Washington state's Lake Washington, where over the past 25 years, plant plankton are now blooming 34 days earlier than the zooplankton that eat them. That's crucial because that's messing with the bottom of the food chain, Kharouba said.

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