Global Warming

Natural World - Out of Synch

A major study has concluded that the delicately choreographed interactions between species that keep food webs functioning are more and more out of synch and the increasing mismatch is consistent with the fact that the environment is getting warmer.

Caribou calves are born later during the thick of blackfly season. Migrating hummingbirds, adapted for a specific spring flower, miss its bloom. Seabirds no longer rear their chicks when fish are most abundant.

The research team found that, as the climate has warmed, events in those relationships have been occurring an average of four days earlier per decade since the early 1980s — about 14 days in total.

Mismatches at the bottom of the food chain could reduce resources all the way up, Kharouba said. One study in a lake found the timing of blooms for the one-celled plants and animals that underlie aquatic life is off by 34 days.

Conservation managers looking after endangered species may have to start taking environmental mismatches into account, the ecologist suggested.

Not all species rely on specialized, carefully timed interactions with other organisms. Others may be able to adapt.

But it’s not always possible for species to work things out for themselves. Some events are driven by warmth and some by day length. One is changing; the other isn’t.

Although more and long term research is needed, there is an undoubted, measurable impact on the long-established relationships between species in nature.