Some nature is noisier than others, as you will probably notice if you attend this weekend's Tracy Aviary Nature Fair.

On one hand you've got the yellow-napped Amazon parrot, a green dynamo who can screech the first few bars of "I Left My Heart in San Francisco." On the other hand there are Jim Piercey's ceramic iguanas.Both are part of the first annual Nature Fair, which will feature the aviary's 800 feathered residents, plus the nature-oriented artwork of more than 20 Utah artists. The oils, watercolors, stained glass, ceramics and photos will be on display throughout the aviary's 12 acres in Liberty Park.

The fair, which also includes exhibits from local non-profit nature, wildlife and conservation organizations, is free to the public on Saturday and $1 for adults (50 cents for children 6 and over) on Sunday.

Piercey is one of four ceramicists from Stone Age Crafts who will display a wide-assortment of items, ranging from Sandy White's chip-and-dip sets decorated with primitive pictographs, to Piercey's cactus lamps. Like much of his work, the lamps are adorned with small, slithering reptiles.

All of the nature artwork will be for sale, with prices as varied as the species represented. Piercey's 4-foot urn-with-iguana sells for $600. Amber Pearson's animal finger puppets will sell for just a few dollars.

Amber, 15, originally started making the clay-head puppets for preschoolers this summer. Her mother, watercolor painter Mary Pickett Pearson, will also display her artwork at the weekend fair.

"I binge paint," explains Pearson, who spends most of her time consumed by the daily tasks of being a mother.

Both amateur and professional artists will be represented, including wildlife photographer Tom Mangelsen, who has had his work published in National Geographic magazine, and oil painter Greg Hunger, an electronics technician at Hercules who paints as a hobby.

In addition to the booths of artwork, the fair will include a town meeting conducted by Rep. Wayne Owens, D-Utah, at 3:30 p.m. Saturday, and the aviary's free-flying bird shows. The bird shows are presented at 5 p.m. every Saturday, 1 p.m. and 5 p.m. on Sundays, and 5 p.m. on Mondays.

"One of the neat things about these shows is that, while the birds are very well-trained, they're not robots," notes Mark Stackhouse, aviary public relations and education coordinator. As if on cue, the opening act - a macaw named Bosco - starts to nibble at the sign welcoming guests to the show.

Bosco got his name, explains Stackhouse, because it rhymes with the bird's most distinguishable word, which also enables him to answer the question, "What is the capital of Russia?"

The 50-minute bird show is directed by the aviary's senior keeper and bird trainer, Steve Chindgren. Fascinated by birds since he was 7, the 37-year-old trainer now deftly coaxes parrots to do Bugs Bunny imitations and ravens to untie shoelaces.

It may not be as dramatic as watching killer whales at Sea World, but the aviary show does include its moments of drama. From high atop the park's towering cottonwoods, a red-tailed hawk emerges from a green wooden box at Chindgren's command and swoops down onto the crowd below.

Chindgren spices his show with useful information (owls may look wise, but their large eyeballs leave very little room in their skull for much of a brain) and ends up with an ecological pep talk.

Parading around the amphitheater with a feisty golden eagle perched on his arm, Chindgren talks about worldwide deforestation, nuclear overkill and a population explosion that has added 14 million people to the earth since 1980.

"We didn't inherit the planet from our parents," he reminds his audience, "we're borrowing it from our children."