The Magdalena Transition is a

marine ecoregion A marine ecoregion is an ecoregion, or ecological region, of the oceans and seas identified and defined based on biogeographic characteristics. Introduction A more complete definition describes them as “Areas of relatively homogeneous species ...

in the eastern Pacific Ocean. It includes the coastal waters along the southwestern Baja California Peninsula, extending from

Punta Abreojos Punta Abreojos is a fishing town in the municipality of Mulegé, Baja California Sur, Mexico. It is located at the entrance to Laguna La Bocana, and is close to Estero Coyote.]s. #Rains, Rains (2006) An isolated hill, high, rises a few miles beh ...

in the north to

Cabo San Lucas Cabo San Lucas (, "Luke the Evangelist, Saint Luke Cape (geography), Cape"), also known simply as Cabo, is a Resort town, resort city at the southern tip of the Baja California peninsula, in the Mexican Political divisions of Mexico, state of Baja ...

at the peninsula's southern tip. The ecoregion includes

San Ignacio Lagoon San Ignacio Lagoon () is a lagoon located in Mulegé Municipality of the Mexico, Mexican state of Baja California Sur, 59 kilometers (37 mi) from San Ignacio, Baja California Sur, San Ignacio, Mexico, and Mexican Federal Highway 1, Highway 1. It is ...

and

Magdalena Bay Magdalena Bay () is a long bay in Comondú Municipality along the western coast of the Mexico, Mexican States of Mexico, state of Baja California Sur. It is protected from the Pacific Ocean by the unpopulated sandy barrier islands of Isla Magda ...

. These lagoons include some of the northernmost mangroves on the Pacific Coast of North America.

Gray whale The gray whale (''Eschrichtius robustus''), also known as the grey whale,Britannica Micro.: v. IV, p. 693. is a baleen whale that migrates between feeding and breeding grounds yearly. It reaches a length of , a weight of up to and lives between ...

s (''Eschrichtius robustus'') migrate annually along the Pacific Coast to mate in these lagoons. The ecoregion is a transition between two marine realms, the

Temperate Northern Pacific The Temperate Northern Pacific is a biogeographic region of the Earth's seas, comprising the temperate waters of the northern Pacific Ocean.Spalding, Mark D., Helen E. Fox, Gerald R. Allen, Nick Davidson ''et al.'' "Marine Ecoregions of the World ...

and the

Tropical Eastern Pacific The Tropical Eastern Pacific is one of the twelve marine realms that cover the coastal waters and continental shelves of the world's oceans. The Tropical Eastern Pacific extends along the Pacific Coast of the Americas, from the southern tip of th ...

. Marine Ecoregions of the World includes the entire Magdalena Transition ecoregion in the Temperate Northern Pacific, but others, including John C. Briggs, conclude that the Tropical Eastern Pacific extends to the vicinity of Magdalena Bay.Robertson, D. Ross, and Katie L. Cramer (2009). "Shore fishes and biogeographic subdivisions of the Tropical Eastern Pacific". ''Marine Ecology Progress Series'', Vol. 380: 1-17, 2009 doi: 10.3354/meps07925, Published April 7 2009.

References

{{reflist Ecoregions of Mexico Marine ecoregions Temperate Northern Pacific Tropical Eastern Pacific