ASHEBORO - The loss this summer of two elderly animals from the collection of the N.C. Zoo heralds a somber milestone for the park. As it approaches 30 years of operation, its older generation has begun to die off.

April, a beloved giraffe who arrived at the zoo before the first permanent exhibit opened in 1978, died last month at age 30. Masha, a polar bear who was old and infirm when he came to the park in 2002, died in June. Both were euthanized after it was determined that nothing more could be done to relieve their discomfort and that they would not recover on their own.

Just as with humans, medical breakthroughs and improved diets have extended the life spans of captive animals, said Lorraine Smith, curator of mammals for the park. While most of the more than 1,100 animals in the N.C. Zoo are youthful and spry, enough are approaching the end of their life expectancies that zookeepers are learning to make accommodations for their geriatric population.

There's Ruthie, the chimp, in her mid-30s; C'Sar, the elephant, also in his 30s; Hope, 32, a lowland gorilla; Monk, a 30-year-old baboon; and a pair of Galapagos tortoises named Tort and Retort that were the first animals to arrive at the zoo in 1973. They were later moved to other zoos but are back, on loan, through October. They are in their 50s, not yet tortoise middle age.

"It's an evolving part of our husbandry," Smith said, "learning how to take care of older animals and meet their needs."

Old age varies by species, and within a species one animal may mature more gracefully than another.

At 30, April was one of the six oldest giraffes in American zoos. Bill Parker, her keeper for the past eight years, said that in recent years, April suffered from osteoarthritis, which made her joints stiff and achy. Also, her weight had dropped. Veterinary staff members gave her pain relievers, and keepers padded the concrete floor of her indoor quarters with topsoil.

"Her death was not unexpected," said Parker, who was off the day keepers arrived at the Forest Edge exhibit to find April down, with her legs splayed out. "We knew she was at the end of her life. But it doesn't make it any less sad when it happens."

Meanwhile, April's suitemate, Julie, is of the same vintage, perhaps a few months older. Except for the slightest fading of the brown spots near the top of her long neck, she shows almost no signs of her age.

The day April died, Parker said, Julie stayed close to the paddock where the animals are kept at night, seemingly aware that something was amiss. Last week, however, she and Azog, April's son, were back to browsing as usual among their habitat's treetops.

Already ill

In the case of Masha, the polar bear, zoo officials always knew they would be providing mostly palliative care. Masha was one of six polar bears that U.S. authorities confiscated from a circus in southern Puerto Rico in November 2002. Operators of the circus kept the arctic animals in small cages in the Caribbean heat, with only occasional access to swimming pools or air conditioning. Federal law requires that they have full-time access to both.

All were lethargic, and some had bacterial infections. Masha also had ulcers and arthritis.

He was thought to be in his early 20s when he arrived at the N.C. Zoo. By the time he died, he was probably 25, "quite old for a polar bear," Smith said.

Because the other bears bullied Masha as he tried to enter the night quarters, zoo staff created a special entrance for him.

The zoo has no immediate plans to replace April or Masha, and no way to know how much, if anything, that would cost. Such decisions are made with the consultation of experts who oversee various zoo animals' "species survival plans." Under the plans, animals are often moved from one zoo to another for breeding purposes, or because of space constraints or exhibit openings.

Many animals also are placed in zoos, including North Carolina's, after federal officials confiscate the animals from people not licensed to keep them or not responsibly caring for them. Other animals at the N.C. Zoo were purchased with donations to the N.C. Zoological Society.

Any time a death is imminent, Smith said, the zoo assembles a team to discuss options and decide in advance when euthanasia is the best choice. Afterward, a necropsy is performed to determine the cause of death, look for any other problems, and determine whether similar symptoms might be better treated differently in the future.

With Masha, Smith said, "We definitely made the right decision. But because polar bears are such personable animals, the decision is very hard on the keepers."

Pet grief counselors have offered to help zoo staff deal with the loss of longtime residents, but Smith and Jennifer Ireland, animal management supervisor for the giraffe and chimp section, said the best solace is talking with colleagues at their own or other zoos. It's not unusual to receive dozens of condolence letters when an animal dies, they said.

"Each animal has a different personality," Ireland said. "You establish relationships."

Diversity helps

Zoos like to maintain diversity in the ages of their collections; younger animals help propagate the species and add interest for visitors. But older animals are necessary, too, especially in species that develop social groups, Smith said. The elders are role models for younger animals, teaching wild and captive behaviors.

As they age, animals' role in the group may change, Smith said. At one time, Hondo, one of the first two chimps brought to the zoo, spent a lot of his time trying to maintain his status as alpha male. Now, at age 32, he is in a group with several young males -- boys, as Smith and Ireland call them -- and has become more laid back and playful. He enjoys his role as wizened sire, mimicked by the impressionable youngsters.

"There's a lot of hero worship going on in that group right now," Ireland said.

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