Are your anchovies killing Africa's penguins?
Overfishing is likely one of the causes of the sharp decline in penguins near Cape Town, South Africa.
Which do you prefer, anchovies on your pizza or penguins in Africa?
Scientists are scrapping over reports this week that the population of Cape Town penguins – called “jackass penguins” for their donkey-like braying calls – have declined by 90 percent since 2004 along South Africa’s west coast, as a commercial fishing of sardines and anchovies has cut into their food source.
“While scientists are busy arguing over the cause of their decline the penguins are dying,” says aviculturalist Karen Anderson of the Aquarium of the Pacific in an interview. “It’s discouraging. It’s just sad.”
This is not the first time this population of penguins has been imperiled. In June 2000, an ore carrier sank off South Africa's coast near Cape Town, dumping more than 1,300 tons of bunker oil on the penguin's rookeries, just as they were hatching and raising their young. Ms. Anderson was among those who responded to help rehabilitate this very same penguin population.
“I helped wash 19,000 birds back in 2000 and another 20,000 were moved while approximately 20,000 were unaffected,” says Anderson. “Yet today the reports are showing just half of those birds survived, just 40,000 birds are left there of that same population. It’s a shame and very discouraging because we worked so hard to save those penguins.”
This week, scientists are locked in debate over what is behind the population’s decline, whether it's overfishing of the birds' food supply or an unknown cause.
According to Anderson, the world’s penguins overall are struggling in the face of manmade incursions, including oil spills, overfishing of sustenance fish, and, in the case of the African penguin, guano mining dating back to the 1800s.
“Before they figured out how to make chemical fertilizers people mined the penguin’s habitats for the guano,” Anderson says. “The guano trickles into the water to nourish the algae which feeds the fish that the penguins eat. You mess with the guano, you mess with the whole ecosystem for generations.”
When penguins try and colonize new lands “they end up interacting with man’s environment, where dogs and other animals eat the birds and their young and they get hit by cars,” Anderson says.
One answer, she says, in the short term “as a boost to help them recover” is for humans to help raise chicks and return them into the population.
For the bigger fix we may need to take our cue from the 2006 animated film “Happy Feet” in which commercial fishing threatened Antartica’s penguins with extinction and the world, seeing the amazing dancing birds, banded together to stop commercial fishing in their waters.
“They probably need a Happy Feet solution, like in the kids movie, but I don’t think that’s going to happen,” says Forrest Galante, marine and wildlife biologist, in an interview. Mr. Galante has interacted with this particular population of penguins on various occasions. “I don’t think you’re going to convince South Africa to stop something that lucrative to its economy.”
Anchovies and sardines, the primary food source for the penguins, have migrated south into cooler waters. The result is that the number of African penguins that feed on them has declined by 90 percent since 2004 along South Africa’s west coast.
Yet despite a ban on commercial fishing set up seven years ago in four key areas, the jury is still out on why the species has continued its decline.
Galante explains that anchovies don’t stay in one place so, “It’s not a matter of where you’re fishing but how much you’re fishing that makes the difference.”
“This is about the overall amount of sardines and anchovies left in the ocean overall because they travel all over the place and so saying you can’t fish them in these four or five spots doesn’t mean anything,” he says. “They pass right in front of the penguins. You can’t just say ‘don’t fish in this pool, but you can fish in the next door pool,’ when the anchovies and sardines all share the same pool. Fish them all out of one and they’re not coming back to the other.”
“We have to decide how much we want ‘em,” says Anderson of the penguins. “We have to take a hard look at what we’re willing to sacrifice to keep these penguins alive.”