Giant devil rays are usually seen in deep coastal waters but are occasionally seen in shallow waters. In a tagging experiment conducted by the Italian National Institute for Environmental Protection and Research (ISPRA), three giant devil rays were tagged and their depth was observed throughout different times of the day. The rays reached a maximum depth of 600–700 meters (1960–2300 feet) but mostly spent their time between 0 and 50 meters (0 and 165 feet); they prefer warmer waters with a temperature between 20 °C and 29 °C (68 °F and 84 °F). The giant devil rays also deep dive at random times, instances not correlated to the time of day unlike how other species deep dive at specific times of day. In other observations studying ray abundance and habitat, giant devil rays were observed alone and occasionally in groups with a maximum of 18 rays. The same study also emphasizes that the rays undergo a species migration across the Mediterranean Sea with the seasons, taking advantage of warm, highly productive waters.