The skinny on shedding

While out walking last month I spied what at first appeared to be a rattlesnake lying in a grassy area alongside a field. Upon closer inspection, I found that it was not actually the snake, but its shed skin. About 15 feet away, I found its former owner hunkered down in a rock pile.

It's a myth that the number of rattle segments on a rattlesnake is an indicator of the reptile's age. The number of rattles actually indicates how many times the snake has shed its skin.

That might be several times a year, depending on how much it is eating and how fast it is growing. Each time the skin is shed, a new segment is added to the rattle. Yet, often during the course of a snake's life the rattle will partially break off or sometimes completely break off.

All arthropods -- insects, crayfish, spiders, etc. - must shed or molt their old exoskeleton and create a new larger one.

For the angler, this knowledge is invaluable. In the shallows of local streams, crayfish exoskeletons can be found lying out in the open while their former owners are hiding underneath nearby rocks. The bait angler knows that crayfish in this softshell stage are the best bait for both trout and bass.

Anglers also should pay close attention to the life cycles of both mayflies and stoneflies. Both undergo "incomplete metamorphosis" in three life stages: egg, nymph and adult. Nymphs are quite small as they hatch out of their eggs. As they grow they continually shed their hard exoskeleton or skin, expand their body, and then harden a new exoskeleton.

Right before the final shedding, stoneflies and mayflies crawl out of the water or swim to the surface. During the final shed, the insect emerges as an adult, complete with wings.

Usually after they hatch, they fly into adjacent forests and wait for their final molt. After molting, they return to the river to breed the next day, with some species of mayflies waiting several days later to return for mating.

Ticks also undergo an incomplete metamorphosis. Tick nymphs closely resemble the adult stage, appearing to be miniature versions of the adults.

Unlike when an adult tick nymph bites you, when a nymph is feeding, it is barely detectable and there is no irritation associated with the bite. In the cases when nymphs have bitten me, a small area of redness on my skin surrounding a tiny black speck has clued me that I was being fed upon.

Each time the black speck was about the size of a period, but I could just make out the shape of a tick, complete with legs and mouthparts. These tick nymphs continue growing and shedding their exoskeleton until they reach their final molt and arrive at the adult stage with which, unfortunately, we outdoor enthusiasts are familiar.