Robert "Bob" Eugene Mahana, of Helena, Montana died at St. Peters Hospital on November 29, 2021, surrounded by his family. He was 72 years old.Bob was born on December 18, 1948 in Great Falls, Montana to his parents Russel Mahana and Junell Salyer. He had one younger brother, Dennis. Bob grew up in Montana and graduated from White Sulfur Springs High School before joining the Marine Corps in 1968. During his military service, Bob rose to the rank of Sargent. Bob was awarded the National Defense Service Medal, Pistol Expert Badge, Rifle Sharpshooter Badge, Vietnam Service Medal, and the Armed Forces Expeditionary Medal, amongst others. Bob began his civilian career working as a police officer at the Fort Harrison VA in Helena before retiring after 35 years as the head groundskeeper. During his free time, Bob was an avid outdoorsman. He spent many years hunting and fishing all over Montana. He was known for his Walleye fishing expertise landing a 33-inch Walleye as his all-time best. Bob would often ski with his son in the winter, when not ice fishing. Bob loved camping and spending time outdoors with friends and family. Bob was a dedicated father. He even built a baseball field for his son and spent hundreds of hours catching pitches. He enjoyed supporting his son by traveling to football, wrestling, and baseball games across the country. In Bob's later years, he loved being a grandfather and playing with his grandkids, reading them books, and taking them fishing. Bob is survived by his son, Jeff Mahana of Helena, Montana and his current wife, Debra Mahana of Helena, Montana. Bob married Debra in 2003. They have been married for the last eighteen years. Additionally, Bob was survived by his three step-daughters Tamera Wise, Jece Wise, and Lisa Wise, as well as three grandchildren. As Bob did not want a funeral, we will celebrate him with a birthday party coming up in a few weeks.Simple Cremation Montana has assisted the family.