The condition of the last female California condor in a breeding pair continued to deteriorate at the San Diego Wild Animal Park. The bird, poisoned by lead shot in an animal carcass, was captured Jan. 3 and has been unable to digest food at least since then. One of only 27 California condors left in existence, authorities say she is the last proven breeder. Veterinarians placed her under anesthesia and probed her upper digestive tract with a microscope, hoping to find it blocked, rather than crippled by permanent nerve damage. However, they found the tract clear and normal, with no sign of blockage. Bill Toone, assistant curator of birds for the park, said the test suggests the problem is "certainly more subtle and possibly more complex than a blockage. One of the fears is there is the possibility of permanent nervous system damage as a result of the high blood (lead) levels that she experienced earlier."