With spring approaching and warmer weather with it, Brookfield Zoo guests will be able to see two fairly new additions on a more regular basis. Two African lions who arrived in 2008 can now be seen daily in their outdoor yard at the zoo’s Fragile Kingdom exhibit.
The pair—Isis, a 3½-year-old female, and Zenda, a 2½-year-old male—both arrived last spring. The behind-the-scenes introduction between the two cats was carefully planned. The gradual process started in July and was completed successfully in October. It began with zookeepers giving the pair visual access to one another, with an off-exhibit space separating them. They were then still allowed only visual access, but with just a wire mesh between them. The physical introduction followed, and the two are getting along quite well as they continue to explore their new habitat. Even though their outdoor exhibit has heated rocks the lions can use to warm themselves, they had access to their indoor off-exhibit space during the winter months.
Isis and Zenda are on loan to Brookfield Zoo from Fort Worth Zoo, Texas, and San Diego Wild Animal Park, Calif., respectively. Since before the arrival of Isis, there has not been a female lion at the zoo for 15 years. The loans were based on a recommendation from the African Lion Species Survival Plan (SSP) of the Association of Zoos and Aquariums (AZA), of which the Chicago Zoological Society (CZS) is a participant. An SSP is a cooperative population management and conservation program for a species. This program manages the breeding of lions in zoos to maintain a healthy, self-sustaining population that is both genetically diverse and demographically stable. Although the SSP has not made a recommendation for the two to breed that may change once Zenda reaches sexual maturity in a few years.
“We are very excited to have Isis and Zenda on exhibit for our guests to see,” said Dr. Stuart Strahl, CEO and president of the Society, which manages the zoo. “A zoo setting is the only place the majority of the public will ever have the opportunity to see such magnificent creatures. Our guests will hopefully learn about the species and make a connection that will inspire them to develop a more caring attitude toward the future of not only lions, but all wildlife and the environment.”
Wild African lions are listed as Vulnerable on the Red List of IUCN— the International Union for the Conservation of Nature, and according to the organization, the population trend for the species is declining. As with so many animals, one of the biggest threats facing lions is the deterioration of their habitat. Today, lions are largely restricted to national parks and other protected areas in Africa south of the Sahara and in one small area of India. Despite their threatened conservation status, African lions are still popular prey for trophy hunters.
A Model of Conservation Management
The Chicago Zoological Society and colleagues from around the world are hoping a new computer tool called MetaModel Manager can help a population of lions in Africa’s Kruger National Park. The lions are dying after consuming cape buffalo that are infected with bovine tuberculosis (TB). MetaModel Manager--created by Robert Lacy, Ph.D., population geneticist and conservation biologist for Chicago Zoological Society, and a team of colleagues--enables researchers to integrate a variety of models to understand the interacting influences of environmental, demographic, and genetic factors on the probability of extinction of threatened species.
Later this month, at the request of the South African National Parks, a workshop will be held on disease impact and management options for the lions in Kruger National Park, with specific focus on bovine TB. The meeting, which is being funded partly by the Chicago Board of Trade Endangered Species Fund, will provide the first real-world test case for the new metamodel tools that have been developed by the biocomplexity network supported by the Chicago Zoological Society. Several researchers involved with the development of the MetaModel Manager program will be attending the session along with lion biologists, wildlife epidemiologists, park managers, wildlife researchers from South African
institutes and universities, and conservation biologists. The information that emerges out of the four-day workshop will be utilized to identify and prioritize additional research needs and to strategize a plan for dealing with the threat of TB in lions. The information will also allow the researchers to gain a better understanding of the complex Kruger system and improved decision-making for the management of the disease.
African lions are the only social member of the big cat family. They live in large groups called “prides” that consist of about 15 individuals of related females, their offspring, and one or more adult males. Unfortunately for them, their social lifestyles may increase the chance that diseases such as TB will spread among pride members. Living in a pride is just one sign that lions are very sociable cats. Another is their large range of vocalizations. Scientists have identified at least nine different sounds that lions make (but a purr is not one of them—large cats do not have the ability to continuously purr the way smaller cats do). Lion vocalizations include a series of different grunts (which seem to be a way of keeping in touch when a pride is on the move), and of course the famed roar, which is often heard at sundown. A lion’s roar can be heard from six miles away.