Bats of Lake Mead NRA
Bats have an undeserved reputation as undesirable creatures, largely due to the myth that all bats carry rabies and pose a danger to humans. In fact, bats are no more likely to contract rabies than any other mammal, and those that do usually do not live long enough to pass the disease onto other animals, except possibly another bat.
Bats are actually ecologically and economically very important to humans. Some species pollinate plants, others disperse plant seeds, and still others consume vast quantities of bothersome insects such as mosquitoes and agricultural pests. In one hour, a bat can eat 600 mosquito-sized insects.
In recent years, drastic reductions in bat populations have been documented worldwide. There are numerous reasons for these declines, including habitat destruction, pesticide use, deliberate extermination and disturbance by humans. A large effort is being made to conserve bat populations and to educate the public that bats are valuable animals worthy of conservation.
At Lake Mead NRA, ongoing studies, using sophisticated equipment, examine, track and record bats in our area. The animals are not injured and are released back into the wild. This information is used to better understand how humans and bats can help each other.
At Lake Mead NRA, one of the biggest threats to bats occurs when people enter abandoned underground mine workings. Many bats roost in these workings because they provide shelter from sunlight, predators and adverse weather conditions.
The Dangers of Disturbing Bat Colonies
• Disturbance of hibernating colonies can cause the bats to awaken and deplete the fat reserves they need to live through the winter.
• Disturbance of maternity colonies is also harmful because adult bats may drop their flightless young or abandon them.
• Established bat colonies may abandon a favored site after repeated disturbances by humans.
• Different bat species have different roost temperature requirements. Therefore, bats that are forced out of a mine may not be able to find another suitable mine and will be forced to leave the area.
The Dangers from Human Contacts
In order to protect the bats, Lake Mead NRA is fitting many mine entrances with specially designed "bat gates." These gates allow the passage of bats in and out of the mine workings, but prevent entry of humans, thereby protecting the bats from both intentional and unintentional harassment and preventing unknowing citizens from entering the hazardous mine workings.
The bat gates are installed 20 feet into the entrance to the mine opening. This allows a shady, protected spot in front of the gate for humans and larger animals to seek shelter in case of an emergency. Additionally, the gates are designed to provide access for larger sized endangered desert tortoise, to enter the mine. Desert tortoises use the mines in the winter to hibernate and in the summer to escape the heat.
Lake Mead NRA asks its visitors to respect these gates as aids to bat welfare and human safety. Abandoned underground mine workings are extremely dangerous and should not be entered. One of the main hazards is lack of oxygen; it is undetectable and will kill you before you have a chance to exit the mine.
Did You Know?
In order to manage invasive plants on park lands, 16 Exotic Plant Management Teams (EPMT's) have been deployed throughout the country. The teams are a new weapon to combat exotic plants. The first test of the EPMT concept was made in 1996 at Lake Mead National Recreation Area. More...