The Ministry of Environment has decided that May and June will be set aside to 'eradicate all bull frog eggs.'' Regional environment offices, local city governments and military authorities will jointly carry out the eradication of the species on a regional basis, it added. Though killing the species can be viewed as anti-environment the ministry has said that bull frogs deserve it because they have been ruining the ecosystem by preying on native animals such as fresh-water crabs, native frogs and even snakes.