Birds that get hungry will typically wander looking for food stuff. Swans like to graze and proprietors need to ensure no poisonous  chemical compounds or pesticides are used on any grass which the birds have access https://nestzyeggs.com/shop/ostrich-eggs-for-sale/https://nestzyeggs.com/shop/chameleon-eggs-for-sale/https://nestzyeggs.com/shop/buy-fertile-crocodiles-eggs/https://nestzyeggs.com/shop/buy-fertile-snake-eggs/https://nestzyeggs.com/shop/buy-fertile-tortoise-eggs/