Cougar Mountain Zoo 2009, Peter Rittler continued in the zoo's management. The zoo collection features 32 exhibits of animal habitats concentrating on endangered species such as tigers, lemurs, wolves, reindeer, cranes, wallabies, macaws, and cougars, among others. On June 16, 2007, the zoo acquired two male Bengal tiger cubs, a royal white and a golden, who were born eight weeks apart in a Florida tiger preserve. The zoo added an additional two cubs in 2009. A glass-walled tunnel called the "Tiger Tunnel" enables visitors to view tigers in close proximity. In 2011, a 370-pound (168 km) tiger was photographed holding his paw up
Hip replacement constituent ions into the blood. Typically these are excreted in the urine, but in certain individuals the ions can accumulate in the body. In implants which involve metal-on-metal contact, microscopic fragments of cobalt and chromium can be absorbed into the patient's bloodstream. There are reports of cobalt toxicity with hip replacement patients. Post operative sciatic nerve palsy is another possible complication. The incidence of this complication is low. Femoral nerve palsy is another but much more rare complication. Both of these will typically resolve over time, but the healing process is slow. Patients with pre-existing nerve injury are at greater