Joseph James Landry, who shot, ran over and hooked Boudreau with a fishing gaff, was granted about 2 1/2 years credit for time served in custody awaiting trial, meaning he would serve about 11 1/2 years.
Boudreau's slaying has affected many people in the Acadian village of Petit-de-Grat, said Judge Joseph Kennedy of the Nova Scotia Supreme Court.
"The repercussions will endure for years, perhaps decades," Kennedy said.
"It has, as the Crown suggested, torn at the fabric of a close-knit traditional area of this province, causing dissension and divide and disharmony amongst the good, hard-working, honest people, many of whom depend on the lobster fishery for their livelihood."
A jury convicted Landry, 67, of manslaughter in November after hearing that Boudreau was the victim of a sustained attack at the mouth of a local harbour on June 1, 2013.
The 43-year-old man's body has never been found.
In a victim impact statement, Boudreau's sister spoke of the anguish she felt "knowing his body was left discarded like old bait."
"You took the life of a son, a brother and an uncle," Margaret Rose Boudreau told Landry, crying and often pausing to compose herself.
"You shattered so many lives."
Landry stared at her as she spoke, his facial expression unchanged.
The Crown had sought a 15-year prison term while the defence asked for a sentence of seven years, minus 2 1/2 years credit for time served.
Crown attorney Shane Russell said Kennedy's sentencing decision was fair.
"He emphasized that vigilante justice is not to be tolerated," Russell said outside court in Port Hawkesbury. "In his words, this was a near-murder scenario."
But defence lawyer Luke Craggs said he thinks the sentence is excessive and will likely appeal.
"That's the sort of sentence career criminals and gangsters get for manslaughter, not guys who have fished for 52 years and pay their taxes and earned an honest living," said Craggs.
Landry will become eligible for parole once he serves a third of his 11 1/2 year sentence, Craggs and Crown attorney Steve Drake said.
Landry pleaded not guilty to second-degree murder. During his trial, the Crown said Boudreau's death was the result of a sustained attack by a three-man lobster fishing crew that included Landry, one of four people charged in the case.
The jury heard that Landry, aboard a fishing vessel that rammed Boudreau's speedboat three times, used a rifle to fire four shots at Boudreau, one of which hit him in the leg.
Landry then used a gaff to hook Boudreau and drag him out to sea before he was tied to an anchor, Landry's trial heard.
Videotaped interviews Landry gave to police were entered as evidence. They showed Landry tell police he shot and rammed Boudreau's boat after Boudreau cut his lobster traps, threatened to set his house on fire and taunted him for years.
"I wanted to destroy him,'' Landry told police. "I was seeing black. I was so mad.''
Landry declined to address the court. The other three accused have yet to stand trial.
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