Under AZA's direction, the Species Survival Plan program began in 1981 to maintain a healthy and self-sustaining population that is genetically diverse and demographically stable. Selection is both practical and political. So-called flagship species like giant pandas, Siberian tigers and lowland gorillas arouse strong public feelings, while lesser known creatures are protected for their importance to ecosystems.
Master plans for each species outline the goals for the population and design a family tree. Sometimes the best course is to stagger breeding or have no breeding at all so the animals won't outgrow holding spaces.
Studbooks contain vital records of an entire captive population of species: births, deaths, transfers and lineage. Computer analysis allows for sound breeding recommendations. Bellinger is the regional studbook keeper for the king vulture even though the zoo doesn't host the species. Occasionally, keepers swap notes at studbook conventions.
Husbandry manuals set guidelines based on the best scientific knowledge for diet and care. Since most zoo animals are born in captivity, it makes it easier when they are traded from one institution to another. Recently, two Eureka-born spider monkeys were sent to the John Ball Zoo in Grand Rapids, Mich., to join a new breeding colony.
The Sequoia Park Zoo joined a project to evaluate the population genetic structures of golden lion tamarins, an endangered species that survives only in a small area of Brazil northeast of Rio de Janeiro. Genetic data derived from hair samples taken from the little monkeys that sport lion-like manes will help determine future management plans for the species.
The project is critical. The tamarins number barely a thousand and about half are in captivity.
Monkeys are much smaller than apes and are more widely distributed throughout the world. They have prehensile tails and are considered, by human standards, less intelligent than apes. What would become apparent later is that chimps are actually 98.4 percent genetically human.
Anthropologists estimate that humans separated from the Pan paniscus line four million years ago. That line later split into chimps and bonobos. Besides DNA, there are striking physical similarities as far as hands, feet, and the nervous and immune systems are concerned. Behaviorally, there are yet more connections.
Goodall and other primatologists have dedicated their lives to studying Bill's relatives and their research has illustrated the intricacies of the large ape's brain. Chimps communicate in a variety of ways from grunting to gesturing.
In
Visions of Caliban, Goodall wrote: "There is one very common communicative signal used by chimpanzees everywhere — a soft, coughlike sound usually accompanied by a sudden raising of the arm. This arm wave looks like a similar gesture made by humans and, for humans and chimpanzees alike, it seems to convey much the same message: 'Leave me in peace.'"
A famous chimp named Washoe learned sign language and could associate the signs with eating and drinking. But evidence is lacking to show that chimps can combine symbols to create new meanings or use syntax. Goodall’s research, however, has shown that chimps can deliberately plan.
When the late Figan, an alpha male chimpanzee, was young he led the other chimps away from their camp then returned alone to help himself to the bananas.
Chimps are also well-known for using tools, such as using sticks to fish termites from their mounds or turning leaves into sponges.
Creationists have long disputed evolution. Realizing the different views, Bellinger says the zoo tries to allow people to appreciate various animal habitat rather than turning it into a religious or scientific debate.
Bill’s quarters were designed to stimulate. He has a fake termite hill with buried treats, a color TV in his backroom tuned to PBS, and then, of course, there's his art.
As part of an enrichment philosophy, Bellinger wondered what Bill would do with watercolors. At first, they thought he might paint his walls, but the chimp quickly learned to operate within the boundaries of the paper after he was shown what the brush would do.
"He didn't have any formal schooling in art," Bellinger jokes.
With his semi-opposable thumbs, the 85-pound Bill, small for his age, was always left alone to create and was never video taped. He selected the colors and went about his work until, at some point, he simply stopped.
The piece was done.
For several years, he had an artistic neighbor, a chimp named Ziggy who died in 1996. His passing received national attention. Ziggy spent his childhood performing in nightclubs until his owner lost control of him as he matured. In 1963, the city rescued Ziggy from an animal shelter.
The two chimps' styles differed quite dramatically. Ziggy was heavy with the colors while Bill's pieces were much more subtle. The paintings were sold at a fundraising art show in Eureka City Hall in 1995.
Life is good for Bill as he receives some of the best medical care available. A birthday party was held in his honor when he turned 50, a milestone for a species that typically survives half as long in the wild. The chimp even received congressional recognition at the well-attended "dress casual" event.
Bill, who now has the full run of the cage after a fence was removed following Ziggy's death, has quit painting. Bellinger said they occasionally offer him watercolors, but he seems to have moved on to other things in life.
He can go into his backroom whenever he wants, but he chooses to stay out in the open with people.
The world has changed ever since Bill came to Eureka. With the closeness in genetics, Bill's treatment in the circus could now, perhaps, be viewed as discrimination. Out of respect, Bellinger doesn’t want to release much about the chimp’s early years until after Bill's death.
While many small zoos are extinct like the animals they were trying to protect, the Sequoia Park Zoo is still holding on to a small corner of the animal kingdom.
That's due, in part, to a few good ambassadors.
Postscript: Bill died in 2007 at the age of 62 after battling a long illness.