Answer:
Adults eat mostly nectar and pollen. Females require a blood meal before they can lay eggs. They suck blood from livestock and humans. The larvae prey on other insect larvae, snails, and earthworms
Read more: http://animals.jrank.org/pages/2501/Flies-Midges-Mosquitoes-Diptera-BIG-BLACK-HORSE-FLY-Tabanus-punctifer-SPECIES-ACCOUNTS.html#ixzz0HQHHw6Qd&B