Waddell died Saturday at St. Michael's Hospital in Toronto after a battle with cancer, said Diane Menzies, his former colleague and longtime partner.
He retired six years ago but began his career with CP in Edmonton in 1975 after working at the Edmonton Journal. During his career, Waddell held a number of positions including Vancouver news editor, Ontario news editor and supervisory editor in Toronto.
Scott White, editor-in-chief of The Canadian Press, recalled how Waddell was unflappable when news broke.
"Shawn was the very essence of what makes The Canadian Press such an important part of the news backbone of this country," he said.
"He was devoted to the news service, relentlessly upholding CP's guidelines on accuracy and objectivity. The Canadian Press is a 24-7 operation and Shawn oversaw the service during nights and weekends. I was always confident with Shawn on the watch. He had an eagle eye for spot news and ice water in his veins. He was impervious to the pressure that comes with the job. I learned a lot from him over the years."
Menzies said it was Waddell's "skewed sense of humour and general irreverence" that attracted her to him.
"Shawn loved working for CP," she said. "He enjoyed chats with (newspaper) members and helping both reporters and editors to shape and polish stories until they sparkled."
Waddell was an avid reader of non-fiction and his mind was full of facts and trivia on every subject except for sports, Menzies said.
"He loved Mark Twain, another writer with a wry sense of humour and great wit," she added.
"He could tell a story or spin a yarn, some of which was probably true. They were always entertaining."
CP legal counsel Stuart Robertson remembered the times he was woken by Waddell seeking advice in the middle of the night with the message: "This is The Canadian Press. Hi! We will call you in two minutes to give you a chance to be helpful." Waddell would then hang up the phone.
"He was bright and relentless in making certain the real story could be told clearly," said Robertson. "I always thought Shawn to be an unsung hero of Canadian news."
Tributes from journalists who worked with Waddell were also sent to Menzies on Facebook.
"(Shawn Waddell) was a classic, with a bemused sense of perspective perfect for the wire, a love of language made for the golden age of newspapering, a taste for yarn-spinning over tables of grog, a love of quirks and oddities and human foibles," wrote Jim Coyle, a columnist at the Toronto Star who worked with Waddell at CP.
Rob Russo, managing editor at the CBC's parliamentary bureau and a former CP Ottawa bureau chief, remembered the wordplay Waddell used in memos he wrote to colleagues.
"Shawn was a terrific writer, but chose to display that talent in his clever desk notes," he said.
No service is planned.
Waddell is survived by a sister and a brother who live in Alberta, and five nieces and nephews.