Honolulu Star-Advertiser © Susan Scott
December 18, 2000
WRITE about ‘opae, a friendly postal worker once suggested as I stood at his window buying stamps.
“What kind of ‘opae?” I asked.
“Any kind.”
‘Opae is Hawaiian for shrimp. So I went home and wrote a column about snapping shrimp. The next week, I was back at the post office.
“Not that kind of ‘opae,” the worker said. “The eating kind.”
Oh. He meant the native shrimp of Hawaii’s estuaries and streams. The problem was, I didn’t know anything about them and could find nothing published.
I soon gave up on the subject, and the postman stopped asking.
Now, years later, I finally have some information about ‘opae, thanks to state biologists Mike Yamamoto and Annette Tagawa. These co-workers at the Department of Land and Natural Resources recently wrote a book called Hawaii’s Fresh Water Animals. In it is everything we always wanted to know about Hawaii’s stream life, including ‘opae.
Hawaii has three types of native freshwater shrimp, all with close ties to the ocean. One type lives in lava ponds with underground connections to the sea. The other two spend the first part of their lives at sea and the rest in streams or estuaries. It is these two species that people like to eat.
One, the mountain shrimp (‘opaekala’ole) makes its home in the mid and upper parts of clean, fast-flowing streams. The 2-inch shrimp tucks itself behind rocks and collects drifting plant and animal material.
To catch food, the shrimp makes a tiny basket out of filaments on its front legs and sifts water rushing past. When the water is slow, the shrimp picks food off the bottom.
Female mountain shrimp carry their eggs on their bellies. After two months, the eggs hatch and the larvae wash into the ocean. Several months later, when the youngsters are about -inch long, they somehow find a flowing stream. Then up they go, moving against the current until they reach their final destination.
The tenacity of these shrimp is legendary. One story tells of a flabbergasted air-conditioner serviceman who found some tiny mountain shrimp on the roof of a building in downtown Honolulu. Apparently, the baby ‘opae had come up a nearby stream, gone through a storm drain, made their way up the building’s five-story drainpipe and ended up in an air-conditioner drip pan.
THE other native shrimp people like to eat is the ‘opae’oeha’a, meaning the crooked-walking shrimp. This name comes from the creature’s uneven gait caused by different-sized pincers.
The crooked-walking shrimp grows to about 3 inches long. Unlike its mountain cousin, it’s a poor climber and stays in Hawaii’s lower streams and estuaries.
Still, it’s an exceptional traveler. Like the mountain shrimp, crooked-walking shrimp hatchlings wash to sea. In about 30 days, the little ones return to their estuary or stream.
Some, of course, don’t make it back. These babies drift around in a suspended state until they reach a river or estuary, be it on Oahu or the Big Island. Because of this ability to survive long periods at sea, crooked-walking shrimp can easily spread throughout the Islands.
Today, Hawaii’s native shrimp and other stream animals are struggling to survive. You can help by never releasing aquarium pets into our streams and by avoiding pesticide use on lawns and gardens whenever possible.
Thank you, Mike and Annette, for enabling me to finally write that eating-kind-‘opae column. I’m sure my postman thanks you, too.