SHERMAN, N.Y. -- A hunter who shot and killed a woman he mistook for a deer as she went on an evening walk with her dogs has been indicted on manslaughter charges, according to the Department of Environmental Conservation.

Rosemary Billquist, a 43-year-old hospital worker, hospice volunteer and marathoner, was killed Nov. 22 while walking her two yellow Labradors, Stella and Sugar, behind her home in the town of Sherman about 5:30 p.m., under an already dark early evening sky.

Hunter Thomas Jadlowski told police he fired a single round from his hunting pistol at what he thought was a deer the length of two football fields away. He heard Billquist cry out, ran to her and called 911. Jadlowski was applying pressure to Billquist's wound when first responders arrived in the field.

The shooting occurred well after sunset, when hunting is prohibited.

Jadlowski surrendered himself to police and was arraigned today in Chautauqua County Court on charges including manslaughter in the 2nd degree and hunting after legal hours.

Jadlowski entered a not-guilty plea. Bail was set at $50,000 cash or $100,000 property. He's due back in court in late January.

The charges carry a potential prison term of five to 15 years, according to a DEC news release.

"I hope this sends a loud and clear message that illegal hunting after sunset is dangerous and will be prosecuted to the full extent of the law," DEC Commissioner Basil Seggos said in a statement.

Billquist's husband, Jamie Billquist, told reporters he was inside his house when the barking of his dogs, who had come home on their own, stirred the first signs of dread.

He rode with his wife in an ambulance to a hospital 30 miles away in Erie, Pennsylvania, where she died.