The National Zoo lost its senior female lion, Lusaka, last evening. A final pathology report will provide more information, but her health had been in decline for several months.
In early 2009, Lusaka developed a mass under the skin on her back. When the mass began to change shape, National Zoo veterinarians performed a biopsy. The test results revealed that the mass was a fibrosarcoma, a cancerous tumor that occurs not just in lions, but also in domestic cats. The tumor was removed by outside veterinary oncologists, and the lion had been on oral medications to slow potential regrowth of the tumor. The Zoo’s animal care staff trained Lusaka so they could collect blood from her tail while she remained awake, which allowed them to better assess her condition.
Lusaka, named for the capital of Zambia, arrived at the National Zoo’s Great Cats exhibit in September 2003 from the Wildlife Waystation, an animal sanctuary in the Angeles National Forest near Los Angeles. Her origin is unknown as she was rescued from a private breeder. Veterinarians suspect her birth year to be 1991, an estimate that made her 18 years of age by the end of 2009. The lifespan of a wild lion is usually about 15 years; for a zoo lion, that number can be 20 years or higher.
Most zoo animals participate in a breeding program called the Species Survival Plan. The SSP scientists determine which animals breed by considering their genetic makeup, nutritional and social needs, temperament and overall health. Because her genetic history was unknown, Lusaka never participated in the SSP for lion management. Rather than breed, she served as an educational ambassador for her species, illustrating the social nature and behavior of lions to scientists, keepers and Zoo visitors.
African lions are listed as vulnerable on the World Conservation Union’s (IUCN’s) Red List of Threatened Species due to pre-emptive killing by farmers as well as prey depletion and habitat loss. However, many populations are thriving in protected reserves. It is estimated that between 6,000 and 10,000 lions currently live in Africa. They are found from the Sahara’s southern fringe to northern South Africa, but are absent from equatorial areas dominated by moist tropical forest. A small population of Asiatic lions, which are endangered, live in the Gir Forest National Park and Wildlife Sanctuary in Gujarat, India.
The Zoo has three young lions: Luke, a male, and Shera and Nababiep, two females.