Fly Fishing Science

FISHERMEN SOMETIMES have ideas or opinions about the marine environment that do not stand up to scientific scrutiny. For example, many anglers believe that changes in barometric pressure strongly influence fish behaviorâ??most notably their willingness to cooperate with anglers. Some have even written that fish can detect a change in barometric pressure before it occurs. An interesting notion, perhaps, though in almost all instances it is incorrect.

A rise or fall in barometric pressure, such as with an approaching cold front, usually means a shift in the weather pattern. And it is the change in the weather, not any fluctuation in barometric pressure, that affects both the fish and the fishing. In fact, most saltwater species probably arenâ??t even aware of barometric variations.

IS COLOR IMPORTANT? This is a serious question for fly tiers and fly fishermen to ask. Some anglers maintain that the choice of color is critical, while others say it is not important. Scientifically speaking, there is evidence to suggest that both points of view may be correct. There is good evidence that picking the appropriate color or colors will, under certain conditions, improve your chances of attracting fish, but science can also show that in other situations, the color of your fly is of limited value or no importance whatsoever.

Fish have been around for more than 450 million years and are remarkable creatures. Over the thousands of centuries, they have made many superb adaptations to survive in the marine environment.

EVER WONDER why some coasts have two high tides while others have one, or almost none? Author Jim McCully did. He asked professors, astronomers, even charter captains, but their responses were inaccurate, incomplete, or flat-out wrong, some erroneously based in waterlore, some on bad science.

After long research, McCully could not even find a lay book that fully explained the phenomenon of the tides. So he wrote Beyond the Moon: A Conversational, Common Sense Guide to Understanding the Tides, released in January by World Scientific press.

“The world is full of people who use the tide tables every day but do not understand the forces of nature that generate the tides,” McCully writes in the opening chapter.