Animal instincts

CNJ staff photo: Sharna Johnson A female spider monkey balances on a tree limb Thursday while playing in her cage at Hillcrest Park Zoo. The limb was introduced as part of the zoo’s enrichment program, which zookeeper Mark Yanotti says helps keep the animals lively and healthy.

By Sharna Johnson: CNJ staff writer

Once a week they get something new, something exciting, something tasty or maybe even frightening. The goal is to get their blood pumping, their brains working and spark their instincts and creativity.

Enrichment activities, which stimulate one of four areas — tactile, environmental, scent or food, are a part of life for about 20 carnivores and primates at Hillcrest Park Zoo, according to Zookeeper Mark Yanotti, who co-directs the program.

Four spider monkeys spent more than six hours Thursday gnawing, jumping on, dragging, pulling and stripping leaves from a tree branch introduced into their cage.

“They had a heyday with it,” Yanotti said.

The three female monkeys went right to the branch, while Binky, the only male, was more skeptical. Eventually he overcame his apprehension.

“Now he’s (Binky) playing with it and tearing it up,” Yanotti said, explaining Binky tends to be the most aggressive of the bunch. “Anything that’s in there, he’s got to destroy it. Search and destroy — that’s his motto.”

Not all activities are playful, Yanotti said.

The scent of prey has been introduced into predator pens to stimulate hunting instincts and vice versa; a predator’s scent in a prey pen brings out survival and flight instincts.

A heavy plastic barrel used to clean the hoofed animal’s pens placed in Blondie the tiger’s pen made for hours of biting, rolling, chasing and jumping, ultimately ending with the barrel’s demise.

Another week zookeepers put bear hair into Blondie’s pen, creating the illusion of a fellow predator nearby.

“He went ballistic. It got him all wound up and ready to go,” he said with a laugh.

Even if the sensation is anxiety, fear or territorial defensiveness, it is a sensation of some kind and it replicates what they feel in the wild, Yanotti said.

“It keeps them alive,” Yanotti said explaining zookeepers don’t want the animals to languish, leaning against the bars of their cages day-in and day-out, he said.

“We can live in our daily bubble as human beings and never get to the edge, but is that really living or is that existing?” For animals confined in cages, that concept is even more significant, he said.

The enrichment exercises, he said, curb problems with depression, poor appetite, destructive behavior and pacing in pens.

It also exposes many of them to things they have never experienced. “These guys are raised in captivity. They have no clue half the time,” he said.

Kathy Yanotti, Mark’s wife and fellow zookeeper, is responsible for the fox, tamarind and two bear cubs expected to arrive soon. She said she enjoys thinking of activities for her charges.

“It’s fun, it really is,” she said.