AZTEC — Aztec commissioners on Tuesday unanimously approved a new agreement between the city and Bloomfield over animal care and costs.

The two neighboring cities have agreed to replace a joint powers agreement, established in 2008, with a less formal memorandum of understanding.

"A joint powers agreement requires approval through the state finance department, which a memorandum of understanding does not," said Larry Thrower, Aztec city attorney. "It's a less formal agreement between entities."

The change was prompted by a request from the city of Bloomfield that billing for costs associated with animals that Bloomfield residents bring to Aztec be made on a quarterly, not monthly, basis.

The city of Bloomfield, which does not have an animal shelter, is billed for a combination of costs for animals brought to Aztec.

Charges, minus individual donations, are a combination of housing, care, supplies, medicine and facility costs per animal.

Beginning in July, the cost per animal will rise from $59.25 to $78.40.

"The cost for animal care, as well as the number of animals received, has gone up and the increase reflects that," said Kathy Lamb, Aztec finance director.

Also in July, Bloomfield residents will have to show proof of residency by presenting a driver's license or utility bill when bringing an animal to the Aztec shelter. Previously, residency was merely a matter of residents including their home address on the shelter's intake paperwork.

This fiscal year through the end of March, Bloomfield was billed more than $28,000 for animal costs, Lamb said.

The city of Aztec also bills San Juan County for animal care. The county, the only other entity charged for services by the shelter, was billed more than $114,000 for the current fiscal year, up through the end of December of 2012.

The county is billed semi-annually, Lamb said.

In the first three months of this year, the Aztec shelter received 1,114 animals, most all of them cats and dogs. Of those, 352 were adopted, and 324 animals were returned to their owners.

In the same period, 241 animals were euthanized.

But the majority of animals are not put down due to a lack of space at the shelter, which has 79 kennels for dogs, 42 kennels for cats and a barn out back for livestock.

Health problems cats are more susceptible to diseases and respiratory infections and temperament issues feral cats and overly aggressive dogs account for the majority of animals put to death.

"It's the least favorite part of my job," said Tina Roper, director for the Aztec Animal Shelter. "Despite the lower numbers this year (of animals euthanized), we make it our mission to try to do everything for the animals to spare them that fate."

If animals are not adopted or claimed, the shelter works with local nonprofits and out-of-state animal organizations to find homes for the animals.

The Humane Society of the Four Corners and the San Juan Animal League offer a low-cost spay and neuter program and provide vouchers through the Aztec shelter to encourage responsible animal care.

Currently, there are three animal shelters in San Juan County, located in Aztec, Farmington and Shiprock.

Roper said the Aztec shelter sees a range of animals.

"You never know what's going to come through the door," Roper said. "It's a different adventure every day."

For more information on spaying and neutering or pet adoption, call the Aztec Animal Shelter, 825 Sabena St., at 505-334-6819.

James Fenton can be reached at; 505-564-4621. Follow him on Twitter @fentondt.