Bats have an important role throughout the world 

Some plants need bats to pollinate them.
Some plants need bat to  disperse their seeds. 
Some bats eat insects and have an important role in pest control.
Certain bats can also act as indicator species informing us of the health of the environment. 

The importance of UK bats

All UK bats eat insects and spiders. Some feed exclusively on midges and mosquitoes but others also eat moths, beetles and crane flies. They play a vital part in our ecosystems where they take the place of birds at night, and help to control insects that might otherwise bite us or be considered as pests for crops and possibly livestock.  In America it is estimated that bats contribute a substantial amount of dollars to the farming industry.  We should help conserve our bats as a natural predator.