Dear EarthTalk: How are the world’s penguins faring in this day and age of global warming? What can we do to help them?
– Mitch McIntosh, Mt. Morris, Ill.
Not surprisingly, penguins—those cute and quirky flightless birds of the Southern Hemisphere that are loved by humans and have inspired countless films, books, comic strips and sports teams—are in deep trouble as a result of reckless human activity.
The nonprofit International Union for the Conservation of Nature (IUCN), which maintains the “Red List” of at-risk species around the world, considers five of the world’s 18 penguin species “endangered.” IUCN classifies five more penguin species as “vulnerable” and yet another five as “near threatened.” Only three species still exists in healthy enough numbers to qualify for IUCN’s “least concern” classification.
Penguins have evolved over millions of years and adapted to big ecosystem and climatic changes along the way, but they face their biggest challenges from threats posed by humans over just the last century.
One of the more dire threats to penguins is commercial fishing. “Overfishing and concentrated fishing efforts near penguin colonies for forage species such as Antarctic krill can make it more difficult for penguins to find nourishment…especially when fishing grounds overlap with the foraging grounds of penguins,” reports the Pew Charitable Trusts, a leading nonprofit with a focus on ocean conservation.
Meanwhile, predators and non-native invasive species introduced by humans are also taking their toll. According to Pew, several colonies of little penguins in Australia, for example, have been wiped out by non-indigenous dogs and foxes, while the Galápagos penguin has suffered big losses as a result of pathogen-borne illnesses introduced by non-native species and some natural bird migration.
Yet another threat is habitat destruction. “Tourism-related pressures, such as foot traffic and litter, can encroach on penguin colonies and nesting sites,” says Pew. “Oil spills have had severe effects on the health of individual colonies of penguins as well as their foraging habitats.”
And climate change—with its resulting melting of vast sheets of sea ice—could well be the greatest threat to already struggling penguin populations. “Ice plays a crucial role in the breeding process for several species of Antarctic penguins and also provides a place for penguins to rest and to avoid predators during long foraging trips,” reports Pew. “The loss of sea ice along the Antarctic Peninsula is contributing to reductions in the abundance of Antarctic krill, a favorite food of several penguin species.”
But according to Pew, the situation isn’t completely hopeless. The creation of more marine reserves where penguins can thrive without the stresses of overfishing and other human activity is a big step in the right direction. Pew is also pushing for better fisheries management in order to increase food sources for penguins and other marine wildlife dependent on nutrients further down the food chain, and also for a reduction in the number of introduced predators and invasive species.
According to Pew, the penguins’ plight is a portent of larger environmental concerns: “These birds are sentinels for the health of the entire sea. Changes to their populations can indicate trouble for other species that depend on these waters for survival.”
CONTACTS: IUCN, www.iucn.org; Pew Charitable Trusts, www.pewtrusts.org.
EarthTalk® is produced by Roddy Scheer & Doug Moss and is a registered trademark of the nonprofit Earth Action Network. To donate, visit www.earthtalk.org. Send questions to: question@earthtalk.org.
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