Recovered tree cover did not bring periodical cicadas back
WHAT THE EVIDENCE SAYS
Researchers compared historical and contemporary tree cover with 2024 periodical cicada distributions and found breeding populations were better predicted by forest cover in 1930 than by current cover. Many reforested areas remained unoccupied despite decades of habitat recovery, and an experimental relocation of 20,126 adult cicadas to apparently suitable restored forest failed to establish a chorusing population.
WHY IT MATTERS / OUR READ
The counter-signal is that habitat recovery is not necessarily population recovery. For species with extreme dispersal constraints and long generation times, historical fragmentation can create a recovery debt lasting many decades or centuries even when the vegetation metric looks repaired.
CAVEATS / UNCERTAINTY
Periodical cicadas have unusually long life cycles and limited dispersal, so the result should not be generalized to all species or forest restorations. Much of the empirical work is from one Iowa landscape, and the relocation result is one experiment shaped by strong predator aggregation.
SOURCE
Ecology · Original evidence
View original evidence ↗
In Iowa, present-day cicada populations were better predicted by 1930 forest cover than by today’s habitat, and a relocation of more than 20,000 adults failed.
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