From Randy Olson: Frogs: Yet another reason we're promoting this term, "shifting baselines"

When the rainforest goes silent...

So whether you want to or not, the sad fact is, in the future, you will all get to know this relatively new term, "shifting baselines." It was coined for the oceans in 1995, but here is an article applying it to the worldwide decline in amphibian populations.

I suppose you could also call it the, "What's missing from this picture?" syndrome. The day will come when people will walk through relatively quiet rain forests and think they are seeing pristine nature, yet not even notice the absence of frog croaks, bird songs, and howls of monkeys. It's about reference points -- if you lose track of them, you may never notice any change.

Here is a quote from the article:

"Furthermore, the lack of historic data on population densities may lead to naive or inappropriate assessments of conservation status, a phenomenon known as shifting baselines syndrome," they write. "Without robust historical datasets indicating precipitous declines, current densities of amphibians and reptiles could be used to suggest that amphibian and reptile populations at La Selva are free from conservation risks. Indeed, all but one of the amphibian species for which we report persistent decade-long declines in protected old-growth rainforests are listed as 'least concern' in the IUCN Red List."