A petrel primer: three tantalizing tidbits
Hawaiian petrel. Photo: Josh Adams / USGS.
“And over this desolate face of nature a stern silence reigned, scarcely broken by the flapping of the wings of petrels and puffins.” —20,000 Leagues Under The Sea, Jules Verne
The mysterious, rarely seen Hawaiian petrel are true seafarers, living nearly all of their lives over the open ocean. Earthjustice is working in the Aloha State on behalf of these endangered birds. Once plentiful throughout the islands, they are colliding—literally—with human development, killed when they fly into power lines.
For the non-birdwatchers among us, these birds may seem to be a nondescript bird species—but they aren’t ‘just another bird.’ Today, Monday Reads presents not one, but three interesting tidbits to better acquaint you with the Hawaiian petrel.
1. Petrels were named after St. Peter. They both walk on water (sort of).
The name ‘petrel’ is commonly thought to have originated from the French version of St. Peter’s name. The birds have long, thin legs (which don’t work too well on land), and several species will slightly dip their feet into the water and seemingly hover while feeding, giving the illusion that they are walking or standing on the water’s surface.
The Hawaiian petrel’s scientific name is Pterodroma sandwichensis, and no, they were not named by a scientist who was exceptionally hungry for lunch. The ornithologist Robert Ridgway named the birds after an early moniker for the Hawaiian Islands, the Sandwich Islands. (And no, this name was not bestowed by a hungry explorer; James Cook came up with it in honor of his patron, the fourth Earl of Sandwich.)
2. Stranded in the ocean? Think that seeing a petrel means land is near? Guess again.
Petrels are pelagic birds, meaning that they spend the majority of their lives out over ocean waters and return to land only to breed. If you’re lost out on the open ocean and you see a petrel, chances are, you’re not any closer to land than before the bird appeared.
Even when the petrel is nominally back on solid ground, scientists have found that they will fly over 6,000 miles on two-week foraging trips—even all the way to Japan!—to find food for their young.
During the months that they spend out on the ocean, Hawaiian petrels will feast on squid, fish, plankton and crustaceans. And when they get thirsty? A built-in desalination system takes care of that; the petrel’s specially adapted bill includes tubes which allow them to “sneeze” out the salt from seawater.
3. One kid a year….for 40 years…
At around six years of age, Hawaiian petrels will begin returning to Hawaii annually to breed, laying a single white egg each year. For the next 40 years, they will go back to the same nest site.
The fact that Hawaiian petrels generally lay only one egg a year (with no guarantees that the chick will survive to adulthood), and take six years to even start the process, is one reason why the population of this unique bird is so vulnerable once the adult population has taken a dip.
One way we can help the Hawaiian petrel is to reduce deaths through such incidents like flying into power lines. A study found that these types of collisions can easily be avoided through measures like shielding the lines with trees, or reducing the height of utility poles. Read more about how Earthjustice is working to have the Kaua'i Island Utility Cooperative implement measures like these. We’ll keep you posted on new developments.