Researchers have determined how sensitive the giant panda's hearing range really is. It is believed that this discovery will help conservationists better assess the disruption human activity inflicts on these endangered animals in their native habitats.

"An understanding of a species' hearing provides a foundation for developing estimates of noise disturbance," explained Megan Owen, associate director of giant panda conservation at San Diego Zoo Global. "For the giant panda, vocalizations are typically emitted in proximity to conspecifics - members of the same species - however the ability to discriminate between fine-scale differences in vocalizations is important for successful reproduction; and so, a thorough understanding of acoustic ecology is merited in order to estimate the potential for disturbance."

For their study, conservation scientists and animal care specialists monitored giant pandas living at the San Diego Zoo. Their findings revealed that the animals can detect sound into the ultrasonic range.

Generally, ultrasonic sound refers to anything above the frequencies of audible sound, which is 20,000 Hz. Therefore, noise from human activities in or near forest areas could be fairly disruptive.

"In order to learn about panda hearing, researchers at the San Diego Zoo worked with giant pandas to teach them to respond, if they could hear sounds at a particular pitch and loudness, thus communicating their ability to hear across the acoustic spectrum," Owen added.

The giant panda is native to bamboo forests in China. One of the animals' primary habitats is located in the Yangtze Basin region, where staggering rates of deforestation and habitat loss occur due to road construction and railroads. In addition to reducing pandas' access to the bamboo they need to survive, fragmented forests isolate panda populations and prevent mating.

While the Chinese government has established more than 50 panda reserves, only 61 percent of the country's panda population is actually protected.

"Through this study, the pandas at the San Diego Zoo have made a significant contribution to our understanding of what may be affecting panda reproduction in habitats in China," said Ron Swaisgood, director of applied animal ecology at San Diego Zoo Global. "It is only because of the strong relationship that animal care staff have with the bears at the Zoo that we have been able to gather this information."

Their study was recently published in the journal Global Ecology and Conservation.