Early attempts to identify sex in sexually monomorphic birds were based on morphological or chromosomal characters but since avian W-specific DNA sequences were identified, their PCR amplification has become commonly used molecular sexing method. We report here a DNA technique that amplifies an intrinsic CHD region without a DNA extraction. This test was applied to twelve species belonging to three waterbird orders, Ciconiiformes, Pelecaniformes and Phoenicopteriformes. All birds were sexed successfully with high reproducibility. There was complete agreement between our results and sex diagnosis by parallel methods. Because the proposed method eliminates the DNA extraction step, this protocol is more efficient and simple. It demands only minute amounts of DNA and reduces both time and the quantities of reagents consumed.