A4 barry run 2-3-4 pics

A4 barry run 2-3-4 pics

Submitted by <p>By Barry Reed</p><p>breed71@gmail.com</p> on Fri, 07/13/2018 - 23:08

It’s in your nature: Protective coloration, a ticket for survival

 

Animals use a number of adaptations to allow them to live long enough to breed and thus perpetuate the species. A porcupine, slow and cumbersome, has hairs that eventually modified into special barbed quills, an almost impenetrable defense. Our striped skunk, with its special anal gland, is able to deter most predators. But why is it black and white, and not an “earthy” brown like a cottontail rabbit or a groundhog?

The skunk doesn’t need to blend in with its surroundings to survive. In fact, its coloration, and that of our ladybird beetles, is designed to be a warning; a red flag, so to speak. Ladybird beetles secrete a toxin from the joints of their exoskeleton which irritates the mouths of the birds that may attempt to eat them. One ladybird beetle may die as the result of a novice bird trying to eat it, but that will be the last one that bird would try to eat. An effective deterrent has unfolded.

Most predators have developed color patterns that help them either hide from other predators or to better hide from or sneak up on their prey. Pickerel, leopard or bull frogs have developed color patterns to allow them to almost become part of their surroundings. This adaptation is called protective coloration.

In an earlier column I pointed out how a deer will have a more reddish brown color in summer, but in fall shed that coat for one that is more brown/gray. Obviously, that more “drab” coat blends in better with the leaves on the fall/winter forest floors. Protective coloration is perfected by them, too. Occasionally an albino deer is born, and if it fortunately survives its first few weeks and you get to see one, you now know a white deer is a stark contrast in a forest or field setting.

The varying hare’s (erroneously called snowshoe rabbit) numbers have been diminishing in Pennsylvania. It changes from its brown coat (about eight months of the year) to a nearly all-white fur. I believe this decline is due to the decline in its upland wet, brushy habitat, and probably more important, our less-snowy winters. Global warming has decreased the amount of snowstorms, thus less snow in these typical coldest months, and the white hares stick out like sore thumbs in a snowless surrounding. (Easy pickings for an owl.)

Finally, most terrestrial predators also use protective coloration. The smooth green snake (from a recent column) is colored to avoid being eaten by hawks, but also so it can conceal itself from its unsuspecting prey. A copperhead is colored uniquely for both reasons as well. Even a bobcat or mountain lion need their coloration to sneak up on their “food.”

To wrap up today’s column, remember, if an insect or smaller mammal is boldly colored, it is advertising a toxin or smell. Most others utilize protective coloration in order to avoid being eaten.

Test your outdoor knowledge: True or False. The number of spots on a ladybird beetle indicates how many months old it is.

Last week’s nature trivia: A barn swallow builds a cup-shaped nest and its long tail can fit over the side of the nest. All the others; bank, cliff and tree swallows nest in cavities, and short tails are a necessity.

Contact Barry Reed at breed71@gmail.com.