"Iguanas 101" by Ronda Kaysen [Sunday Source, Aug. 29] showed a lack of research punctuated by the fact that the article's accompanying photograph featured not an iguana but a Savannah monitor.

Kaysen played down or ignored the difficulties involved with keeping an iguana. She did not mention that adult males can be aggressive, even when raised by "thoughtful owners." She also oversimplified the problems of housing.

While one can put a mesh or wire screen in front of the door of a spare room, it is difficult to maintain the high temperatures (80 to 88 degrees, with a basking area near 95 degrees) and humidity levels (75 percent to 80 percent) that iguanas require and still have a home that is comfortable for the human inhabitants. Additionally, the room -- unless fastidiously cleaned every day -- would develop a strong odor of iguana excrement, uneaten vegetable products and mold.

Kaysen also ignored the health risks associated with salmonella when she suggests allowing iguanas to swim in a bathtub and teaching them to ride around on a shoulder. Iguanas are wild animals, not toys. On warm and humid days they will benefit from, and may enjoy, a bask in the back yard. But they should never be "shown off" by being walked around the neighborhood!

Many of the health problems that iguanas and other reptiles face in captivity are related to the effects of stress on various body systems. Captivity in and of itself is a source of stress that good reptile owners try to minimize by mimicking as closely as possible the pet's wild environment.

-- Susan Felter

Silver Spring

The writer is the veterinarian for MARS Reptile and Amphibian Rescue.