Tag Archives: Tide

Life at -4.6 Feet

A couple of times every year the moon and sun align – literally – to bring about very large tides. In June this year, a full moon delivered a -4.6 tide to Hoonah, Alaska and provided a glimpse of life under the sea. Rocky shorelines were converted into tide pools full of life trapped there by the receding waters. The first time I experienced one of these monster tides was  in May 2016 right after moving to Hoonah. The joy I find in perusing the beaches and flipping rocks to see what is beneath has not diminished since that time. Thanks to Bob Armstrong’s guide, I am able to identify some of the creatures we found.

The Star Fish

Of all the animals in a tide pool, Sea Stars seem to provide the most variety to the color, textures, shapes, and sizes that have evolved in the ocean. In some places they cover every rock surface or bottoms of tide pools. They are the ever-present predator scouring for crustaceans, snails, and clams. We enjoyed looking at their colors and touching their rough (and sometimes slimy) skins.

Blood Star.
Mottled sea star
The close, rough texture of a Mottled sea star
Slime Star (species not known)
Mottle Sea Stars cover the bottom of a tide pool.

Tide Pools, Alaska, Wrinkled slime star
Wrinkled slime star

The Octopus

We found the crab shells before we found the octopus den. The tell-tale shells were only a foot or two away from a crevice containing 8 arms with quarter-sized suckers. Th octopus was so large that we could only see one arm, and wait as we might it never came out of the den. Fortunately a smaller octopus – about the size of a football- motored by us. They are intelligent and lithe creates known for their camouflage. It was amazing to watch the colors of the small octopus’s skin turn from a light pink to dark red as it moved from rock to rock and tried to blend in.  It was the first time I had watched a wild octopus! The 12″ deep water provided a window into its life below.

A crab shell let us know that an octopus den was near.

Tide Pools, Alaska,
An octopus swims by in the shallow waters of the low tide. It was a real treat to watch this animal hunt!

Crabs

Crabs are really remarkable creatures. They have adapted themselves to all areas (niches) of the inter-tidal zone in search of food. We must have found 8 or 10 different species, but some of them stood out for their uniqueness. Spines, claws, and camouflage make them fit for the niche they fill. The most bizarre was the Butterfly Crab – it is hard to imagine what its oblong shell would provide. Perhaps it camouflage?

A young king crab hangs out in the inter-tidal. Eventually this crab will descend to deeper water.
Tide Pools, Alaska, Butterfly crab
A butterfly crab was one of the most bizarre creatures I have every found! I cannot imagine why its shell needs to be shaped like that.
A Decorator Crab attaches pieces of seaweed to itself to provide almost perfect camouflage.

Bobbin’ Around Under Water

Below the inter-tidal we found this bright orange sponge. This sponge was accessible because of the low tide.

Broadbase tunicate 

A day spent looking into tide pools is time well spent! Exploration allows you to discover new things, observe new behaviors, and breath in the sea air. I look forward to the next big tide!