San Lorenzo Marine Archipelago National Park
San Lorenzo Marine Archipelago National Park is a national park in Mexico located on San Lorenzo Island, which is part of an archipelago in the Gulf of California, off the east coast of Baja California.
The island and the surrounding areas are part of a rich ecosystem made up of a great variety of marine flora and fauna.
It is a protected area by the Mexican federal government due to the importance of its habitat and the presence of several endangered species. The archipelago is part of the municipality of Mexicali, Baja California. The island is located southeast of the city separated by the Salsipuedes Channel.
The San Lorenzo Marine Archipelago National Park was therefore created to protect the fragile and important ecosystem of the San Lorenzo archipelago; the establishment took place by national decree of April 25, 2005. The rich marine biodiversity with a significant number of threatened, vulnerable and endangered species has made it necessary for the Mexican federal government to protect this area. This area is also important as a commercial, cultural and recreational area.
The San Lorenzo Marine Archipelago National Park includes the archipelago islands of San Lorenzo, Las Animas, Salsipuedes, Rasa and Partida and includes the surrounding maritime boundary of the islands. This park has a total area of 50,442 hectares. The islands of the Archipelago are surrounded by deep, cold, nutrient-rich waters in the central part of the Gulf of California, also known as the Sea of Cortez. Most of the park is included in the maritime area. The small land portion consists of jagged islands with rugged coastlines eroded by many sea cliffs. The islands of the archipelago show dramatic topological changes where the elevation ranges from sea level to 485m above sea level. The highest elevations are found on the island of San Lorenzo towards the southern end.
The climate of the San Lorenzo Marine Archipelago National Park can be considered dry desert with an estimated annual rainfall of 65 mm and an average annual temperature of 25 °C.
The high levels of solar radiation and constant prevailing winds result in high evaporation rates. The islands of the San Lorenzo archipelago experience hot summers where temperatures during the hottest months of the year (July and August) reach between 35°C.
Winters are warm with average low temperatures reaching 10°C during the coldest months of the year (January and February). Winds affect the climate of the islands, but have a more significant effect on sea conditions. In the winter, northwest winds prevail, bringing nutrient-rich waters from the Pacific Ocean into the Gulf of California, but during the summer, southerly winds prevail, having the opposite effect on the currents.
The San Lorenzo Marine Archipelago National Park is characterized by unique ecosystems and habitats. These ecosystems support a large nutritional pyramid that is important for surrounding marine animals, birds, and human settlements.
The islands can feel arid due to a lack of fresh water and arid conditions that allow for only a few desert shrubs and cacti. The marine flora consists of different varieties of algae. Algae serve as an ideal habitat for small marine species.
The rich waters of the Gulf of California are home to over 800 fish species and 2,000 invertebrate species.
The fauna of the San Lorenzo Marine Archipelago National Park consists of the following list of endangered species: blue whale, humpback whale, killer whale, sperm whale, green turtle, hawksbill turtle, olive turtle, totoaba. The ecosystem of the San Lorenzo Archipelago consists of many varieties of commercially important fish. In the waters surrounding the islands, swordfish, hake and dolphin risso are also common. Rasa Island is an important nesting site for Heermann’s gull, elegant tern, American oystercatcher, Craveri’s murrelet and brown pelican. Heermann’s gull and elegant tern are estimated to reach numbers of 260,000 and 200,000 respectively, representing about 95% of the total world population of these species. Salsipuedes Island, Las Animas Island, and San Lorenzo Island are important breeding habitats for the brown pelican in the Gulf of California. An average sum of breeding pairs of brown pelicans on the three islands is estimated at between 6,000 and 18,000.
The islands are also home to a large number of bird species consisting of native species as well as migratory species attracted by the rich marine ecosystem. Some of the most observed bird species are: Cooper’s falcon, golden eagle, peregrine falcon, Columbidae, magnificent frigatebird, brown pelican and Nazca booby.