India, Aug. 31 -- Yellowstone National Park is warning visitors to follow posted signs as biologists begin their annual grizzly bear capture and study operations. The work starts next Monday and will continue through October 15, as reported by The Independent.

To monitor the population, biologists use road killed deer and elk to bait traps. The bears are caught in culvert traps, metal tubes with sliding doors, or in foot snares designed to hold a paw. Once secured, the animals are sedated with tranquilizers. Scientists then examine the bears, collect health data, and fit some with radio collars to track their movements.

Affected areas of the park, which spans nearly 3500 square miles across Idaho, Montana, and Wyoming, will be clearly m...