The Sea of Cortés, also known as the Gulf of California, or Vermilion Sea; locally known in the Spanish language as Mar de Cortés or Mar Bermejo or Golfo de California) is a body of water that separates the Baja California Peninsula from the Mexican mainland. It is bordered by the states of Baja California, Baja California Sur, Sonora, and Sinaloa with a coastline of approximately 2,500 mi. Rivers which flow into the Sea of Cortés include the Colorado, Fuerte, Mayo, Sinaloa, Sonora, and the Yaqui. The gulf's surface area is about 62,000 sq mi.
The Sea is thought to be one of the most diverse seas on the planet, and is home to more than 5,000 species of macroinvertebrates, and can be separated into three faunal regions, Northern, Central, and Southern. One recognized transition zone is termed the Southwestern Baja California peninsula. Transition zones exist between faunal regions, and they usually vary for each individual species. Faunal regions are distinguishable based on the specific types of animals that are found there.
The narrow sea is home to a unique and rich ecosystem. In addition to a wide range of endemic creatures, like the critically endangered Vaquita Marina, it hosts many migratory species, such as the Humpback Whale, California Gray Whale, Killer Whale, Manta Ray and Leatherback Sea Turtle, and the world's largest animal, the Blue Whale.
The Sea of Cortés sustains a large number of marine mammals, many of which are rare, and endangered. Its more than 900 islands are important nesting sites for thousands of seabirds and its waters are a primary breeding, feeding, and nursing grounds for a myriad of migratory and resident fish species. For decades, the gulf has been a primary source of two of Mexico's leading marine resources, sardines and anchovies. Water pollution is a problem, but the more immediate concerns are overfishing and bottom trawling, which destroys eelgrass beds and shellfish.
Three general types of shores found in the Sea of Cortés include rocky shore, sandy beach, and tidal flat. Some of the rich biodiversity and high endemism that characterizes the Sea of Cortés can be attributed to seemingly insignificant factors, such as the types of rocks that make up a shore. Beaches with softer, more porous rocks (such as Coquina limestone, rhyolites, granite, or diorite) generally have a higher species richness than those with harder, smoother rocks (such as basalt or diabase). Porous rocks will naturally have more cracks and crevices in them, making them ideal living spaces for many animals. The rocks themselves, however, generally need to be stable on the shore in order for a habitat to be stable. Additionally, the color of the rocks can affect the organisms living on a shore. For example, darker rocks will be significantly warmer than lighter ones, and can deter animals that do not have a high tolerance for heat. The northern Sea of Cortés experiences tidal ranges of up to 16 ft. Mixed semidiurnal tides are the norm throughout most of the Sea.
Today we dove within The Corridor. Along the 18 mile tourist corridor between Cabo San Lucas and San Jose Del Cabo there are 5 great dive sites. The topography of this sites are very different from the ones at the Cabo San Lucas Marine Park. The boat ride to the sites takes anywhere between 10 and 30 minutes from the Cabo San Lucas Marina. Schools of dolphins and jumping pigmy manta rays are often seen on the way to the dive sites. I can’t tell you the number of large species we saw, to include rays and groupers to rival those in northern Hawaiian waters. Our two dives, at Blowhole and the little known Falcon, were largely warm, about 82 degrees, with a few thermal clines that left us shivering.
We ditched our meal plan today (took it for only 3 days), and walked along the marina until we saw Wayne’s favorite sign -- Wi-Fi zone. Let me tell you, there was a happy man with his iPhone over lunch. I could see him debating whether or not to return to the hotel! At 18 dollars a day per device for internet, free, and fast, was appealing to not only him!
Back we went, had the customary siesta, and enjoyed a little pool time in the hour just before sunset. Then we went back, made dinner, and relaxed. And Wayne started planning for the next trip, using different hotels -- some with free internet! =]