HILO — In an effort to control the Big Island’s wild donkey population, about 100 of them are being taken to California.

KITV reports the Humane Society of the United States is planning to remove the donkeys on a chartered plane next month. Humane Society Hawaii’s director Inga Gibson says they’ll go to animal sanctuaries.

Drought conditions led the donkeys from the highlands into a populated area in search of water. Donkeys were appearing near the highway and a school. 

The Humane Society and a local veterinarian have been trapping and sterilizing animals from the rapidly growing population estimated at about 400 to 600 donkeys. 

At the end of the month, a clinic is to be set up at a ranch to castrate captured male donkeys.