Eight-year-old Moonbeam watches from her cage as prospective adopters walk by. Some stop to read her biography and marvel at her beautiful coloring. But after a short while, they continue on. This is Moonbeam's eighth week living at the animal shelter waiting for her new home.

Such is the typical life of a homeless older pet.

While millions of middle-aged cats and dogs older than 8 fill shelters across the country, it's the cute and cuddly kittens and puppies or bouncy young adults who usually find homes first. It's heartbreaking to watch mature pets waiting for a family to welcome them into their home while they are overlooked among the appealing youngsters.

What many don't realize is that older pets are not only as lovable as their younger counterparts but they also possess wonderful qualities that are unique to their age.

Let's face it: While we all love them, puppies and kittens are a handful. Like children, they have an abundance of energy and require a lot of time and patience. Young pets need to be house trained and require proper training and socialization to ensure that they grow up to be good adult citizens. With a senior pet, you won't have to go through these difficult periods, and you won't find yourself cleaning up after accidents.

Keep in mind that with older pets, "What you see is what you get." A senior cat or dog's personality is fully developed and it has already grown into its looks. A kitten or puppy may surprise you down the road because its true personality and appearance are still unknown.

Older cats and dogs also settle quickly into their new homes. No one knows this better than Rev. Stacey Grossman, who adopted Molly Brown, an 8-year-old collie mix, in the spring.

The pastor of the Church of the Nativity in San Rafael and also a competitive rower, Grossman wanted a pet who would complement, rather than compete, with her lifestyle. "Molly has bonded to me like glue," she says. "Molly is happy to be with me no matter what I'm doing."

With so many great reasons to adopt an older pet, why is there hesitation on the part of potential owners? Advances in medical technology mean that pets are now living well past what used to be considered a normal lifespan. Today, cats are living into their 20s and many dogs enjoy life well into their mid-teens.

People might be afraid that an older pet will have nothing to offer. But mature cats love to play and snuggle. Dorothy Andrews adopted 9-year-old Frenchie, a colorful calico, last winter. "I don't even think of her as older," Andrews says. "In fact, Frenchie is very lively and gets plenty of exercise. She especially loves bouncy toys."

According to the American Veterinary Medical Association, 45 million pets in the United States are at least 8 years old. This translates to a quarter of the nation's pet population. So if you're considering a new pet, maybe it's time to give a mature animal a second glance.

Carrie Harrington is the Public Information Assistant at the Marin Humane Society.

Tails of Marin appears every Saturday in the Home & Garden section of the Marin Independent Journal