BANGOR – Today the Bangor Humane Society will celebrate the 10th annual Spay Day, a public service program encouraging pet owners to spay or neuter their pets.

While the message of responsible dog ownership trumpeted by animal welfare groups has left several animal shelters in southern Maine scrambling to meet a growing demand for puppies, northern Maine is facing the opposite problem.

According to Becky Brimley, director of animal welfare at the Bangor Humane Society, northern Maine shelters, including those in the Bangor area, are dealing with problems of overpopulation. Brimley said that Bangor area shelters have even sent animals to southern Maine.

Steven Jacobsen, director of the Animal Welfare Society Inc. shelter in Kennebunk, said there has been a widespread shift in attitudes toward dog ownership during the past 20 years in that part of the state. Not only are dog owners neutering their pets, they are taking better care of them. And there are simply fewer dogs being born, he said.

Brimley contends that this is not the case in the northern portion of the state, where not as many pet owners spay or neuter their pets.

“We are currently experiencing a major cat crisis,” Brimley said, speaking of the overpopulation in shelters.

Deborah Clark, director of the Animal Refuge League of Westbrook, said the shortage in southern Maine is a sign that animal welfare groups are doing their job in spreading the message that owners should neuter or spay their dogs.

“This is exciting and something to be really proud of,” Clark said.

Brimley agrees that underpopulation in shelters is what they are working for. “While we are delighted to have people adopting pets, we are not here as a market provider,” Brimley said.

The public service announcement to be aired today features footage of homeless and unwanted pets being cared for at the Bangor Humane Society.

“We hope that by highlighting the tragic result of not spaying or neutering, people will be encouraged to get their pets fixed,” said Brimley.

Area veterinary clinics, including Blake, Brewer, Maine Coast and Veazie, will offer reduced rates or evening hours as part of Spay Day. For information, visit www.bangorhumane.org.