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PUBLISHED: 4:40 PM on Thursday, May 25, 2006
Creatures of low tides in a rocky pass

Photo by Barbara Turley
  There is room for everyone to explore the inter-tidal area.
The abundant inter-tidal life along all the beaches in Southeast Alaska is a never-ending source of interest if one takes along a field guide or two and spends some time looking at the many tide pools, rock faces and under rocks exposed by low tide.

It goes without saying that a rock turned over should be carefully put back just the way it was in order to preserve the micro-habitat for the animals dwelling there. Although there will be many similar species of such things as limpets and sea stars throughout Southeast, the exact combination of species on almost every beach is unique.

The colder water near glaciers contributes to differences as does the stronger waves in exposed areas. For many years, my family has scheduled beach excursions for all of the lower low tides that we can manage. In the summer, this means morning tides around the time of the full moon. One July, we had the opportunity to enjoy some of these low tides in the Rocky Pass area between Kuiu and Kupreanof Islands, just south of Kake on a three-generation, eight-day canoe trip. Our group included my husband Kim, his parents, two of our college-aged children - John and Mariann, our high school-age daughter, Kathy, and Denise, a friend of John's from school (later to be our daughter-in-law).


Photo by Barbara Turley
  This 3"-diameter crab is found under rocks in inter-tidal areas.
We split up in our early morning beach explorations from the Kadake Bay Forest Service cabin on Kuiu Island on the morning of the first significant low tide on this trip. Kim and I took a canoe and paddled out to a steep-walled islet at the south end of the bay. In the clear water, we had beautiful views of starfish, anemones, and bright orange sea cucumbers.

Kathy and Mariann explored streams and tide-pools on the extensive dry beach. Among other things in their bucket, they had a sand lance, a shiny silver fish about the size and shape of a ballpoint pen. They had another species we never did identify. It was slightly bigger and similarly long and skinny, but it had very large pectoral fins and long, narrow jaws and an angular head like a tube snout or a sea horse. The lower jaw was longer than the upper jaw. It was dull greenish brown on the back and bright golden on the belly.

We camped at Horseshoe Island that night. At 8:37 the next morning there was a tide of -4.0, which is exceptionally low. The beach at this point was composed of a solid outcrop of rocks, layered in several stair steps. Boulders of various sizes were scattered about on it. Much of the lower part of the beach was draped with huge seaweed with dull green leaves seven or eight feet long and eighteen inches wide. In a tiny tide pool that was formed by water cupped in the folds of one of these leaves, we made our first major find.


Photo by Barbara Turley
  Our first turtle crab remained unidentified until we got home and found it in a field guide.
It's hard to say whether it's more exciting to encounter something new that you've never even heard of, or to find something you've read about and know about and have always hoped to see. This discovery was of the latter type. It was a tiny pink and black striped fish called a grunt sculpin. Perhaps they are called a grunt sculpin because their face resembles a pig's with a long, blunt-ended snout.

There were a great variety of creatures to see on this beach. The grunt sculpin was an accidental find, something that could turn up at any beach. Rather than being a creature of the inter-tidal habitat, it was a sub-tidal species stranded in a tide pool by the dropping water. The chance of finding exotics like this is always one of the intriguing things about a low tide.

On this beach, though we were only about 125 miles from Juneau, the different inter-tidal species were exciting. We found several specimens of a small crab that we'd never seen in Juneau. They were white or pale gray in color. Their back shell was a bit longer than it was wide and completely covered their legs and body parts, other than their heads. The shell flared out beyond the width of their body and legs like wings. Viewed from the top, they looked like a moth resting with its wings open. We later learned that they are Cryptolithodes typicus, with the common name of "turtle crab."


Photo by Barbara Turley
  This 2" grunt sculpin was about the cutest fish we'd ever seen.
We made another discovery that we also did not identify until after the trip. We were not even certain to what kingdom the black leathery substance that was attached to some rocks belonged. It grew in round or oblong mounds ranging up to two or three inches across and about half an inch deep. We called it "puppy paws" because it felt and looked a lot like the pads on a dog's feet. We later learned that it was Codium setchellii, a kind of algae or seaweed. We enjoyed the great variety of chitons, sea stars, sea cucumbers and other creatures. We found a spiny lumpsucker, one of our favorite little fish, with a big head and tiny tail that make it look like a cartoon fish with personality.

We camped next on Eagle Island. Because the turn of the tide comes about an hour later every day, the morning's low tide was at a more comfortable hour. The tide was almost as low as on the previous morning. The little channel that remained between Eagle Island and Kuiu Island was so narrow that you could throw a big rock across it.

In this habitat of relatively flat, rocky bottom with strong currents, we found some different species of inter-tidal animals from those at Horseshoe Island. We saw some interesting tubeworms. Out of the water, they looked like hollow, four-inch gray sticks, about the diameter of a pencil. They were in clusters of a dozen or more. On those that were submerged in tide pools, a one-inch diameter "feather duster" was protruding from the end of each tube. These are used to strain microscopic food from the water. Some were dark brown, some a rich, warm brown, and some purple. They would zip out of sight into the tube instantly if touched.

Green sponge was very common, growing in little mounds on the rocks. There was also a bright orange algae-like substance that coated some rocks. When we looked closely, we discovered ?-inch long nudibranchs of exactly the same bright color on the orange growth. Kathy found a large gumboot that we saved for dinner that day.

Low tide at any of the beaches in Southeast Alaska exposes a habit that is exciting to explore. Field guides boost the enjoyment. Realizing when you are seeing something that you have never seen before greatly adds to the pleasure of boat or kayak trips to new areas.


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