Recently, second-grade classes from Milton School, led by Rye Nature Center staff, took field trips to Rye Town Park for an up-close-and-personal look at the kinds of marine organisms that live in Long Island Sound’s intertidal zone.
By Bill Lawyer
Recently, second-grade classes from Milton School, led by Rye Nature Center staff, took field trips to Rye Town Park for an up-close-and-personal look at the kinds of marine organisms that live in Long Island Sound’s intertidal zone.
While it’s nice to visit an aquarium to see various marine habitats and organisms on display, nothing beats the “real thing.” Rye schoolchildren are extremely fortunate to have the great environmental education resource of Rye Town Park’s Oakland Beach.
The first “hurdle” that the some of the school children had to get over was that Long Island Sound is not a chlorinated, sanitized swimming pool. There are living things, carrying out their daily lives, by the beach.
Under the careful supervision of the teachers and naturalists, children were free to pick things up, look at them, and put some into containers for further study. Seine nets were used to catch organisms that swim. Naturally, the children were attracted to things that move. Catching a big crab in the seine net elicits a lot of excitement. Two of the organisms easiest to find and examine, barnacles and seaweed, may be common, but most people know little about them.
Barnacles are often dismissed as annoying creatures that get attached to boats. They might not be cute and cuddly (or funny, as in Sponge Bob Square Pants), but they have proven to be important environmentally, academically, and commercially. Just recently, The New York Times had an article in their Dining section about the tasty gooseneck barnacles from Spain and Canada. Barnacles are a good example of how different vertebrates, including humans, are from invertebrates. And how radically they can change from one stage of development to another. In their larval stage they can move about, but as adults barnacles attach themselves to all sorts of things, from rocks to whales.
Marsha Richmond, a history of science professor at Wayne State University, describes how Charles Darwin spent nearly eight years researching and writing about the characteristics and classification of barnacles (Cirripedia). Darwin applied his research to his developing theory of evolution based on phylogenetic relationships. This was long before the discovery of DNA! For his work, he was rewarded with a medal from the Royal Society of London in 1853.
On the plant side of intertidal ecology are the various types of seaweed that almost always get left behind as the tides go out, twice daily at Oakland Beach. One of the most interesting examples of adaptation is illustrated by bladder wrack seaweed.
Any child who has encountered some bladder wrack, and gotten over the initial reaction — “it’s slimy, it’s yucky” — has invariably been attracted to the (as the Seaweed Industry Association puts it) “small nearly spherical gas–filled vesicles (bladders) which look like bubble wrap and occur in pairs, one on either side of an obvious central midrib running along the center of the strap-like frond.”
These bladders allow the plants to float on the surface of the water, thereby getting more sunlight at high tide. Unlike non-aquatic plants, they don’t get their nutrients from soil. Instead of roots, they have “hold-fasts” which as the term implies, holds the plant on rock or other solid, inter-tidal surface.
Bladder wrack seaweed is just one of many varieties that are harvested and used for food, medicine, and other commercial products.
This article only scratches the surface of the many fascinating and little-known “characters” of Oakland Beach’s intertidal habitats. Keep in mind, that playing in the sand isn’t just for kids as the parents on these field trips had just as much fun.
