The Sea of Cortez, also known as the Gulf of California, separates the Mexican mainland from the California Baja Peninsula, one of the longest and most isolated strips of land in the world.

Peppered with small islands, where huge colonies of sealions can be seen basking on the white, sandy beaches, the gulf is fed by many rivers flowing in from the 4,000 kilometres of coastline, including the Colorado.

These waters are home to a rich and unique ecosystem. Humpback whales, manta rays and leather back turtles are migratory visitors, while permanent residents include fin and sperm whales; and grey whales come in winter to mate and give birth. This is also one of the best places in the world to see whale sharks. Water temperatures in the Sea of Cortez vary between 27 to 30 degrees in August and September and 18 to 21 degrees in January and February. This ensures a great diversity of resident and visiting marine life.