Elwood L. "Buck" Perry, 90, who invented the Spoonplug fishing lure and is considered the father of structure fishing, a system calculated to help anglers find their catch, died Aug. 12 in Taylorsville, N.C. No cause of death was reported.

A lifelong fisherman, Mr. Perry concluded that fish move predictably along routes dictated by underwater topography, following contours in the lake or streambed. He also learned that they spend much of their time in deep water and move along the contours to shallow water, where they become more active. How far they go depends on several conditions, including the weather.

To help figure out where fish -- any variety of freshwater fish -- would be, he crafted a device that combined elements of lures known as "spoons" and "plugs," which he patented in 1946 as the Spoonplug. He described it as "a shoehorn that's been tromped on by a horse."

Mr. Perry designed seven sizes, the largest for deep water to the smallest for shallow. To map a river or lake bed, he used the smaller ones first to tap the bottom and gradually substituted larger sizes to go to deeper water until he found fish. Mr. Perry could cover a new lake in a few hours.

He never accepted the excuse that fish weren't biting, responding: "You've got to go out and make them strike."

In 1973, Mr. Perry published "Spoonplugging: Your Guide to Lunker Catches." In 1981, he published a nine-volume Home Study Series about structure fishing. He also published a newsletter, "The National Spoonplugger," and for many years was education editor for Fishing Facts Magazine.

In 2000, In-Fisherman magazine named him to the Freshwater Fishing Hall of Fame.

The Spoonplug failed to take off in its first decade, but in 1957, Mr. Perry was invited to demonstrate its effectiveness in the "fished out" Lake Marie near Chicago. When he pulled out fish after fish, the Chicago Tribune and others published feature stories. Anglers started buying Mr. Perry's tackle.

He toured the country for many years, teaching others how to use his structure fishing system, which many called simply "Spoonplugging."

Born July 10, 1915, in Hickory, N.C., Mr. Perry received a degree in physics and mathematics from Lenoir-Rhyne College in Hickory, where he starred on the school's football and baseball teams.

He taught math and physics at Hickory High School and helped coach sports before moving to North Carolina State University to study mechanical engineering. He served in the Army Transportation Corps during World War II.

Mr. Perry worked briefly in a family business after the war and then started manufacturing Spoonplugs in his garage.

His company expanded to other products for a time, including golf clubs and specialty furniture parts. But after a lightning-strike fire destroyed the plant in 1971, Mr. Perry rebuilt and concentrated on selling Spoonplugs and other tackle.