Post-mortem examinations performed during May and August of 1997 on three free-living green turtles (Chelonia mydas) in the United Arab Emirates revealed that all had stomachs full of fresh seagrass (approximately 99% of the total ingesta) and presented with a duodenal volvulus involving a length of approximately 100 cm. Duodeni appeared empty and necrotic with diffuse purple-black mucosa. No apparent signs of obstruction by foreign objects, acute endoparasitism, or other disorders were observed. In all cases, duodenal volvulus was diagnosed, the cause of which may have been dietary in origin. The rise in water temperature, with an associated rise in the temperature of seagrass, thus enhancing the over-fermentation of ingesta with the subsequent liberation of excessive amounts of gas was the probable cause of volvulus formation. Ingestion of foreign bodies and physical movement also are discussed as causes of digestive disorders. It is recommended that handlers should avoid 360° rotation when overturning turtles onto their carapaces.