Ocean Views: Marine animals and the sound of spring rolling in

Wed, 04/04/2012 - 10:44pm

Although there is great promise of warmth and new life in April, the month can be cold, grey and bony: a month with an exoskeleton.

But April also beckons for beach walks, a time when almost anything can be found at the island’s edge. The shoreline can be wide and flat at low tide, or narrow and cobbly at high tide. And the edge can have a complete personality change in a mere 24 hours, depending on wind and sea action. One day, April’s warmth is a siren call to the sandy beach; on another, the sky and surf are both frothy azure – alluring but sharp – and hasten the walker to change directions to place the wind at the back and off the cheek. On still another April day, a beach walk can be chilly and clammy, and simultaneously steamy-warm: a walk cloaked in spring fog.

Early spring seas can toss large and small wonders at the feet of walkers: gnarled tree trunks and limbs, marine carcasses, scampering sanderlings and flights of seaweed. It is in our animal nature to seek a glimpse of marine animals when strolling by the sea. Common loons, schooling stripers, lobsters, spouting whales leap instantly to mind. But the variety of marine animals (other than birds, fish, shellfish and mammals) found at our island’s edge is wondrous and diverse. When asked to name a marine animal found in our environs, an uncommon few will name the sand dollar, sea star, anemone, sponge, or sea horse – and yet all are animals that can be (and have been) found by walkers on Crescent Beach in past years.

Here are a few fun facts to ponder on an April beach walk.

• Sand dollars and sea stars (no longer called star fish) are echinoderms – spiny-skinned – marine animals that evolutionarily are not even closely related to fish.

• Sea anemones are a soft-bodied polyp-like animal. These non-mobile animals stay anchored in one spot. The mouth of this animal is positioned in the water column (or at the surface) and is surrounded by tentacles to capture and direct food. Sea anemones are in the same phylum as jellyfish. Anemones and jellyfish have a similar body structure and similar ways of capturing food, but one form is stationary and one is mobile.

• Sponges, once thought to be plants, are the most primitive of multi-celled animals. Sponges are a strange group; it is often hard to discern between a single animal and a colony. Common sponges in our area come in a range of forms, from small vase-like forms to spongy encrustations. Larger sponge species are found throughout New England waters but generally live in deep sub-tidal waters. However, broken bits often find their way to our wrack line.

• Sea horses are true fish, but with some very unique habits. Sea horses use their prehensile-like tail to cling to stems of eelgrass and suck plankton from the surface of eelgrass through their snouts. Female sea horses deposit their eggs in a pouch on the underside of the males, where they remain until they hatch. Look for sea horses among eelgrass or along shores near eelgrass beds, especially on the north side of Hippocampus*, where heavy wave action can dislodge the little animals.

An old islander, Otto Mitchell, would say of the din originating from a big April southeast swell meeting the shore, “that is the sound of spring rolling in.”

The following events and Ocean View Foundation programs will provide opportunities to listen to the sounds of spring washing over us and to keep an eye peeled for new views and understandings of our animal world.

April 3 and 17, 8 a.m.: Crazy-as-a-Coot Bird Walk, call 595-7055 for location.

April 5, 6 p.m.: Winter Pot Lucks: Film & Food. Island Library showing of "GasLand."

April: Listen and look for woodcock sky dancing.

April 21, 8 p.m., Spring Twilight Walk & Night Sky Viewing, Hodge Preserve.

April 21: New Timber doodle* Moon.

April 22: Earth Day

April 27: Arbor Day


* Go to the Ocean View Foundation Facebook page to answer the questions: where is Hippocampus, and what is a timber doodle?