Tram Chim National Park is around 40km due north of Cao Lanh and notable for its rare red-headed cranes (Grus antigone sharpii), though more than 220 species of bird live within the reserve.
The cranes nest here from about December to May; from June to November they migrate to northwest Cambodia. Seeing them requires a considerable commitment (time, effort and money), with Dong Thap Tourist organising expensive trips by car and small boat (5,000,000d); it's cheaper to go if you make friends with locals.