Pay attention to the 'ecosystem canaries' which act as warning signs of ecological collapse

Monday, August 29, 2016 by: J. D. Heyes
Tags: ecosystems, canary species, environmental collapse

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(NaturalNews) As tens of millions are aware, the biodiversity of Planet Earth is under assault, and we have reached a point where we'd have to go back 65 million years in order to find rates of species being decimated at the levels at which it is taking place today, the UK's Guardian reports.

While conservative efforts traditionally concentrate more on larger animals like whales and polar bears, the vast majority of "life" on the planet is barely discernible, if at all, like bugs that can appear and vanish from ecosystems without much apparent impact.

In reality, biodiversity is necessary for our overall survival, because the more biodiverse our planet, the more resilient it is. Decreasing biodiversity is a lot like taking nuts and bolts out of a machine one at a time; missing a few may not matter much to its overall operation, but eventually, if you remove enough of them, the machine breaks down.

The same is true with the earth. Loss of forest and topsoil can lead to desertification of the land, and so forth.

A new study published in the journal Ecology provides some evidence that biodiversity may have an importance that has thus far been overlooked, yet is nevertheless vital if mankind is to manage the human impact on various ecosystems.

'Canary' species

"Global environmental change presents a clear need for improved leading indicators of critical transitions, especially those that can be generated from compositional data and that work in empirical cases," says an abstract of the study.

The study notes that some rare species may be "canary" species, in that they could provide early warning of an impending ecological disaster. Specifically, researchers theorize that information about the overall health or resilience of a particular ecosystem is hiding in data pertaining to species once believed to be unimportant.

Additionally, scientists believe that the existence or absence of some rare species may also provide "important clues" about how close an ecosystem may be to extinction, noted James Dyke, a lecturer in sustainable science at the University of Southampton who was involved in the study.

Like the canaries that coal miners used to monitor for poison gases deep under the ground, so-called "ecosystem canaries" very often are the first species to vanish from an ecosystem that is under duress. Their disappearance may be tied to changes in the way ecosystems function, which then provides a signal that a collapse may be eminent.

"Our study used data collected from lakes in China that showed changes in the abundance of species from algae (diatom) and aquatic midges (chironomid) communities as they compete for resources under environmental pressures," Dyke wrote in The Guardian. He added that the data made it possible to identify three organism types: One that slowly replicates but is a fiercely competitive "keystone" species; fast-replicating "weedy" species that are not very competitive; and slowly replicating, weak "canary" species.

Restoring biodiversity is harder than preventing its loss in the first place

Fertilizer runoff from surrounding fields has had a profound impact on the lake ecosystems, the scientist noted. And as the situation grows more severe, the canary species will become the first to suffer.

As all species continue to degrade, Dyke notes, the eventual collapse of the keystone species will occur as they are replaced by the weedy species. As keystones are lost, that triggers a critical transition for the ecosystem, arriving at a point where it shifts into an alternate state. In lakes, that leads to domination by smothering algae and an absence of many plant and animal species.

Making the lake clear again, and therefore biodiverse, is very difficult, says Dyke, so it is better to avoid the collapse in the first place – hence, his research.

If one were to wait to observe changes in the keystone species, it would likely be too late to save the ecosystem, because by then it will already have begun its rapid decline and eventual collapse. So the goal should be to look for changes in population structure of keystone, weedy and canary species, to predict events years or even decades before the actual event, Dyke noted.

Sources:

TheGuardian.com

OnlineLibrary.Wiley.com

Science.NaturalNews.com