Saturday, April 11, 2009

Biodiversity and the Quest for Balance

There was a pause in the breeze, on one of those crisp fall days that foretell colder days to come.  Yellowed dogwood and aspen leaves already littered the swampy forest floor, providing temporary cover for tree frogs and field voles.  As the breeze picked back up, a lone hiker emerged out of the mist, studiously watching the ground as he moved through the trees.  Hearing a slow trill, he bent down, looking intently, and spied what he was looking for – Hyla chrysoscelis, the gray treefrog.  As it turned slightly, he noticed the leg.  A fifth leg, sprouting from the middle of an otherwise-normal back limb.  He stood straight sharply, taken aback.  This was the sixth deformed frog he had found this season.

Although the story above is fictitious, the essence of the passage is a very real story that gripped the scientific world between 2000 and 2004.  Reports from all over the world document both a general decline in amphibians and the alarming increases in deformities and unnatural growths.  Was it some odd fungal infection?  Was it a legacy of the decades of pesticides, fungicides, herbicides and other synthetic chemicals that had been dispersed throughout the environment?  No one was sure, to believe the report in the 2003 Scientific American, which hypothesized several possible causes: contaminated water, ultraviolet radiation, or a parasite.[1] And an article in the March-April American Scientist of 2004 linked many of the amphibian problems to human-induced climate change.[2] 

What was clear was simply that something was wrong.  Amphibians, with their highly permeable skin, act as canaries in the coal mine, and signal that something is amiss in the world's living systems.   And it was highly probable that human activity was culpable in some way.

In how many other areas have we seen significant detrimental impacts in our lack of balance with Mother Earth?  And perhaps more importantly, why do we so often fail to restore balance, once we see what we are doing?  

All life is sacred, and our fellow beings are key threads of the web of life, yet our actions too often do not make this recognition.  As we see, amphibians are not the only threads in danger.  

- Bats under Siege.  Similar, to the frog decline, 2008 and 2009 found tens of thousands of bats killed, in relation to a white fungus which is somehow involved, and has had a 50-90% fatality rate in infected bats.  The ultimate cause is not known.[3]

- State of the Songbirds (Aububon Report).   The Aububon Society in 2007 reported on the population changes of several common bird species in North America, and found twenty species had declined at least 50, and in some cases, 80 percent.[4]  The critical factor is the loss of habitat – i.e. the grasslands, wetlands, and healthy forests that have been taken through development.  This largely tracks the 50-80%% of wetlands that have been lost throughout the U.S., according to the U.S. Geological Service.[5]

- The UN Millennium Ecosystem Assessment.  This project of the United Nations  looked at the services provided to humankind by nature.  The report's scientists found that "approximately 60% (15 out of 24) of the ecosystem services examined in this assessment are being degraded or used unsustainably".[6]

We clearly have our work to do.  Of this, more to be said later.

[1] Bustein, A. R. and P. T. J. Johnson. 2003b. Explaining frog deformities. Scientific American 288: 60-65.
[2] Kiesecker, J. M., L. K. Belden, K. Shea, and M. J. Rubbo. 2004. Amphibian decline and emerging disease. American Scientist 92:138-147.
[3] "Bats Perish, and No One Knows Why", Tina Kelly of the New York Times, March 25, 2008.
[4] Common Birds In Decline, The Audubon Society,
[5] Loss of Wetlands in the Southwestern United States, Roberta Yuhas of the U.S. Geological Service, 1996.
[6] Ecosystems and Human Wellbeing: Opportunities and Challenges for Business and Industry, The United Nations, 2005, p. 6.

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