Like the canaries that used to be brought into coal mines as early warning signals for toxic gases like methane, the world's penguins are sounding an alarm of potentially disastrous ocean changes.
Of the seventeen species of penguins, twelve are declining rapidly in number and are listed as endangered or threatened.
A study published in 2008 by a Professor of Conservation Biology at the University of Washington links this widespread decline in penguin numbers, in large part, to human activity.
Rising Ocean Temperatures
One cause is the rising ocean temperatures and increasingly erratic temperature and climate patterns.
In the Antarctic Peninsula, where many penguins breed, temperatures are rising five times faster than the average rate of global warming, and sea ice covers forty-percent less area off the peninsula than it did twenty-six years ago.
This decrease has led to reduced numbers of krill, the main source of food for some penguins, as well as for many of the fish species that penguins feed on.
Human Activities Impact Penguins
But it is not just climate change and melting ice that is putting penguins at risk. Other human activities are having serious impacts on penguin habitats and their food supplies. These include over fishing, guano mining, and rampant coastal development.
In addition, oil pollution from drilling and shipping industries has impacted penguin populations throughout the southern hemisphere.
A Serious Warning
Canaries were used as sentinels in coal mines because they were more sensitive to toxic gases than humans. Their deaths warned miners to get out before it was too late.
Similarly, penguin populations respond rapidly to changes in the marine environment, and serve as a warning that we are doing a poor job of managing our oceans, which could lead to potentially catastrophic consequences.