Stop by Carlsbad Caverns National Park these days around sunset and you'll be able to see not just one or two bats, but possibly as many as 400,000 as they exit the cave en masse for their nightly meal.

The bats -- Brazilian free-tails -- blast out of the cave to go off in search of insects for dinner. According to park officials, the best "flights" are seen exiting the cave during the months of July and August, when baby bats born earlier in the summer join in the dinner rush.

You also can see the bats return to the cave after their nocturnal smorgasboard, but you'll need to rise early (or stay up really late). "Early risers can see the bats as they re-enter Carlsbad Cavern with spectacular dives from heights of hundreds of feet," notes the park staff. "Individual bats diving in from every direction may reach speeds of 40 km/h (25 mph) or more."

Prior to the evening bat flight, a program is given at the cavern entrance by a park ranger. The starting time of the talk varies with sunset—it is best to call the park at 575.785.3012 or check at the visitor center for the exact time. Programs may be canceled in the event of inclement weather, such as rain and/or lightning. Bat flight programs are scheduled from Memorial Day weekend through mid-October. There is no charge for the bat flight program. In late October or early November, the bats migrate to Mexico for the winter; they return in April or May, depending on the weather.

Every summer the park invites the public to rise early and join park rangers in watching the bat's return flight. In 2011, the event will be held on Saturday July 16 from from 5 to 7 a.m. Breakfast is available for purchase at the Carlsbad Caverns Trading Restaurant in the Visitor Center starting at 5 a.m. Park staff offer a variety of special programs.