No. 58–Potpourri

From time to time I’ll make an observation or come across a tidbit of information that, while interesting, would be difficult to flesh-out into a full column. At other times I’ve had to leave information out of columns because of space limitations. I’ve been making note of these instances for a while now and will share them on occasion under the title “Potpourri”.

Incompatibility: One of the things I learned early on at the old North Street Aquarium was that care must be taken when picking creatures to share a common tank. Some lessons learned, I’m sorry to say, were fatal to some of my unfortunate early acquisitions as in blue crabs will eat anything else in the tank, large whelks will eat small ones and a hermit crab will kill and eat a snail and move into the shell.

I knew that fish ate fish but I didn’t expect any trouble when I introduced a small red drum, about four inches, to the tank of a speckled sea trout of equal size. Imagine my surprise the next morning to observe the trout swimming about with two inches of the tail end of the drum sticking out of its mouth.

Pecking order: There are, I’ve learned, considerations less fatal in consequence and yet of importance when selecting tank mates. While they may not eat each other, some will be more aggressive at feeding time and must be satisfied before others can get their share. Size and mobility are the two main factors in determining who eats first.

Where to tread: After years and countless hours trekking our estuarine intertidal zone I have developed a sense where and where not to step to keep my boots on my feet. Here are a few tips to help assure your footwear doesn’t become a future archeological find.

Rule #1, if it’s dark brown and shinny, don’t step there. That’s pluff mud capable of swallowing you up to your knees.

In many places the upper intertidal zone offers relatively sound footing of packed sand or tide deposited loose oyster shell or a mix of the two. The lower in the zone you venture the less stable the ground is likely to be. As you move perpendicular to the waterline you will find the sand and shell deposits are irregular regarding how far toward the water or along shore you may wander.

Also, there is often a transition zone where a sand or shell layer will become thinner with pluff mud underlying it. When in an unfamiliar area, I walk gingerly in approaching questionable areas and test progressive steps with weight on my back foot and slowly applying it to the lead foot.

I would note here that how one walks plays a role in traversing an area un-muddied. Some people clump along shifting weight side to side as they go while others seem to glide. Gliding will take you further.

Another factor to be taken into consideration is an individual’s weight. At 130 pounds I’m able to go where a down lineman may not and youngsters I take on field trips are able to go where I may not. It’s been my experience, however, that children glory in mud and, despite warnings, will stomp themselves into need of rescue of them and their boots.

Mud walkers extraordinaire: More than once I have observed in fascination as a great egret has moved along a mud bank in search of a meal. They are elegant gliders but the real secret is in the structure of their feet. With one toe to the rear and three forward spread wide, weight is sufficiently distributed on the mud surface to prevent sinking. When taking a step, the toes fold down as the foot is lifted breaking the glue-like adhesion we experience. As the foot moves forward the toes snap open again to meet the mud.

Over time I’ve toyed with idea of mud-walking devices that would allow me to explore the flats I’m now denied access to. A snowshoe-like apparatus would distribute weight but is impractical because of the surface adhesion. A design involving hinges and accompanying springs for retracting “toes” seems the way to go but it’s pretty far down on my to-do list right now. Any engineers out there looking for something to do in your spare time? I’d be more than happy to test your prototype.