News & Events

Cataract Surgery Improves Zoo Eagle’s Quality of Life

September 12, 2007, a clinical team at the William R. Pritchard Veterinary Medical Teaching Hospital successfully removed cataracts from both eyes of a 35-year-old bald eagle named "Modoc."

The feisty bird, a once-wild specimen unable to live on its own, came from the Micke Grove Zoo in Lodi, California (see note below). Zoo officials had noted that the animal’s blindness sharply reduced its ability to move around, find its food and maintain an awareness of its surroundings.

Zoo manager Ken Nieland stated, "Micke Grove Zoo staff is committed to ensuring the best possible quality of life for animals under our care. Opportunities such as that provided by the eagle eye surgery not only offer hope for an improved life for this bird, but also hold promise for increased knowledge and skill in treating other animals that share a similar condition."

To reduce possible complications in the aging animal, the eagle received a complete workup at the Companion Avian and Exotic Pets Service prior to surgery. Faculty members and technicians closely monitored its anesthesia. Two eye surgeons used ultrasound equipment to gently break up and extract the cataracts. Fourth-year veterinary students observed the surgery magnified on a video screen in the surgical suite. As they watched, a resident from the Ophthalmology Service (see PDF poster here) quizzed them about avian eye anatomy and answered questions about the procedure.

The bird’s veterinarians reported after the surgery, "He's doing great and can see very well now." They treated the eagle for several days before it returned home. Zoo officials expect a big improvement in the bald eagle’s quality of life now that it can see again.



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The following information, written before Modoc's treatment, comes from Micke Grove Zoo:

Bald Eagle To Receive Cataract Surgery

"Modoc", a 35-year-old male bald eagle and resident of Lodi, California's Micke Grove Zoo, is scheduled for eye surgery at the University of California, Davis Veterinary Medical Teaching Hospital. The 25-year zoo resident has been diagnosed with cataracts in both eyes. This is a relatively common, age-related condition that often progressively leads to blindness.

The eagle originally came to the Sacramento Zoo in 1974 with a broken wing from a gunshot wound. After surgery to repair the wing, a two-year recovery and rehabilitation effort was undertaken. Though the eagle was outfitted with a tracking device and released on San Clemente Island off the Southern California coast, his failure to forage led to recapture. For the past 28 years, "Modoc" has been exhibited at Micke Grove Zoo. Since 1987 he has shared his enclosure with a female eagle, "Shaman", acquired from the UC Davis Raptor Center and the recipient of a successful corneal transplant. Trauma sustained in the wild, however, has left her blind in one eye. There has been no successful breeding with the pair.

At Micke Grove Zoo, "Modoc" receives an annual physical examination, routine blood tests and vaccinations. During a physical examination in May of 2006, the Zoo’s veterinarian, Dr. Jackie Gai, noticed that the eagle had cataracts developing in both eyes. Cataracts affect the lens of the eye, and obstruct vision. One eye was more affected than the other, but "Modoc" was still able to see. Dr. Gai and the Zoo staff have monitored the bird closely since then and have observed that the cataracts have progressed to the point where "Modoc" is virtually blind in one eye and has minimal vision in the other. Dr. Hollingsworth, an ophthalmologist at U.C. Davis, examined the eagle and recommended surgery.

An expert team of veterinary ophthalmologists, avian veterinarians, and anesthesiologists will perform the delicate surgical procedure to remove the cataracts at U.C. Davis Veterinary Medical Teaching Hospital. If successful, the procedure will not only enhance the quality of life for this bird, but it will also provide hope for wild eagles that sustain eye injuries by advancing our knowledge and skills in treating this type of condition.