David Leslie, a Twin Cities stockbroker who would rather be in the woods, at the lake or in the mountains with his children and friends, was a playful but serious nature lover.

Best known for inventing the Hummer Helmet, a baseball batting helmet with hummingbird feeders attached at eye level, Leslie parlayed his love of the tiny birds into an appearance on David Letterman's late-night TV show in 2005.

"I'm sure he was somewhat surprised to get on the Letterman show," said Jack Davis, 84, of St. Cloud, a lifelong friend. "But he shouldn't have been, because he was just so knowledgeable about the birds."

Leslie, 84, of Minneapolis died Feb. 5. Born in Minneapolis in 1928, Leslie was a hockey player at Breck School and Dartmouth College on his way to becoming a stockbroker at Piper Jaffray in Minneapolis. But his children remember him as a family man who took them boating, fishing, hunting, skiing and hiking.

"David sort of introduced me to hunting, and over the years we probably took 100 weekend hunting trips together," recalled Leslie's son-in-law Bill Reynolds of Orono. "He was just interested in the natural world. When we went duck hunting, it was about seeing the birds, watching them move and seeing how they reacted to the decoys. If you got a shot at them, that was a bonus. I think he was a kid at heart."

Cynthia Johnson, the eldest of Leslie's children, recalls her father's pulling them on skis behind a snowmobile and teaching them how to tie fishing flies for trips to trout streams.

"He was not your typical stockbroker," Johnson said, of her father, who was known to refer to his downtown Minneapolis work environment as "the asphalt jungle."

"He'd rather have been raising his five children in the real jungle, swinging from the trees," Johnson said.

She also recalls time spent at their lake cabin, on family skiing vacations and at a rented house on Cape Cod in Massachusetts. Later, she became his deep sea fishing buddy on trips to Florida.

When Leslie and his wife, Mary, bought a cabin in northern Wisconsin, it was a fortuitous location because there were a large number of hummingbirds there. Leslie began by feeding them out of large conventional hummingbird feeders, then designed the Hummer Helmet to watch the birds at close range; the attached feeders were only inches from his face. All his family members and many family friends were given helmets, and he even sold some, Johnson recalled.

Johnson persuaded KSTP-TV to do a story on her father, which led to exposure on the Animal Planet cable channel and, the following spring, an offer to appear on Letterman's show. The producers used a remote camera in a Twin Cities nature center to show him interacting with hummingbirds. Letterman periodically checked in with Leslie during the hourlong show.

"Dad was on the show for the entire hour, bantering back and forth with Letterman," Johnson said. "I think Letterman got a kick out of it, and Dad got a kick out of it, too."

Leslie seemed to charm others as easily as he had Letterman. "David had a unique kind of sparkle about him," Reynolds recalled. "Everybody loved him."

"Everybody was his favorite person," Johnson said. "And everybody knew that."

He is survived by four of his five children, David Jr. of Stillwater, Okla., Cynthia Johnson of Bloomington, Marcia O'Hagan of Minnetonka and Peter of Coon Rapids. Services have been held.