Bambilynn Pederson, age 11, of Duluth, Minnesota, for her question:

What is a salmon fly?

This tiny fly looks somewhat like the fragile mayfly    minus the long tail. Both make brief appearances in the spring, when myriads of their relatives swarm in the warm air. Both have gauzy, fairylike wings    though the mayfly's are larger and it does more flying. The look alikes have different basic features and scientists classify them in separate insect orders. The salmon fly is one of over 1,000 stoneflies that share the Order Plecoptera, meaning twin winged. As its name suggests, it is destined to play a fish food role in the scheme of nature.

Most of its life is spent in the cool, clear streams where young salmon take their leisurely time swimming to join the sea. When the salmon fly comes up for air during her short and hectic mating season, it is already several years old. The previous phase of its life was spent as a nymph    a wingless, immature adult. The little tawny brown larva takes its oxygen from the water    and teeming numbers of its relatives provide food for the growing salmon.