Montague Island, known in

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many Latin American countries **Spanish cuisine Other places * Spanish, Ontario, Can ...

as Isla Montague, is an island at the mouth of the

Colorado River The Colorado River ( es, Río Colorado) is one of the principal rivers (along with the Rio Grande) in the Southwestern United States and northern Mexico. The river drains an expansive, arid watershed that encompasses parts of seven U.S. s ...

in the municipality of Mexicali,

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

, and is part of the

Colorado River Delta The Colorado River Delta is the region where the Colorado River flows into the Gulf of California (also known as the Sea of Cortez) in eastern Mexicali Municipality in the north of the state of Baja California in northwesternmost Mexico. The ...

and part of a broader region called the

Salton Trough The Salton Trough is an active tectonic pull-apart basin, or graben. It lies within the Imperial, Riverside, and San Diego counties of southeastern California, United States and extends south of the Mexico–United States border into the stat ...

. It is about in length along its longest axis.The Delta of the Colorado River
David L. Alles (ed.), Western Washington University, August 6, 2006. The Colorado River Delta region experiences some of the highest tidal ranges in the world, up to , and at the highest tides, Montague Island is completely inundated. Although the islands in the delta have changed much over time, a map of the region shows Montague Island in 1873. The island is uninhabited, as the climate is very hot, arid and the area occasionally floods. The nearest inhabited town is El Golfo de Santa Clara.

Ecology

The climate in the region of the Island is extremely hot and

arid A region is arid when it severely lacks available water, to the extent of hindering or preventing the growth and development of plant and animal life. Regions with arid climates tend to lack vegetation and are called xeric or desertic. Most ...

, with average annual rainfall of 2.4 in (60 mm). Montague Island, as part of the Colorado river delta, has had its ecology radically altered by diversion and use of water upstream in the river. The only water reaching the delta, with the exception of occasional floods, is

agricultural wastewater Agricultural wastewater treatment is a farm management agenda for controlling pollution from confined animal operations and from surface runoff that may be contaminated by chemicals in fertilizer, pesticides, animal slurry, crop residues or i ...

. At least seven species of water birds are known to breed on Montague Island. The island is one of two known active breeding colonies of

elegant tern The elegant tern (''Thalasseus elegans'') is a tern in the family Laridae. It breeds on the Pacific coasts of the southern United States and Mexico and winters south to Peru, Ecuador and Chile. This species breeds in very dense colonies on coa ...

in Mexico. During two years, a large number of nests were destroyed by

tidal flooding Tidal flooding, also known as sunny day flooding or nuisance flooding, is the temporary inundation of low-lying areas, especially streets, during exceptionally high tide events, such as at full and new moons. The highest tides of the year may b ...

, but there were only low levels of nests lost to

predation Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

. The birds nesting on Montague Island have reacted strongly to

El Niño El Niño (; ; ) is the warm phase of the El Niño–Southern Oscillation (ENSO) and is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific (approximately between the International Date ...

, with

brown boobies The brown booby (''Sula leucogaster'') is a large seabird of the booby family Sulidae, of which it is perhaps the most common and widespread species. It has a pantropical range, which overlaps with that of other booby species. The gregarious brow ...

being replaced by blue-footed boobies, and an increase in nesting of least, elegant, and royal terns, as well as black skimmers. Montague Island is one of the few locations where '' Mulinia coloradoensis'', an endangered species of

clam Clam is a common name for several kinds of bivalve molluscs. The word is often applied only to those that are edible and live as infauna, spending most of their lives halfway buried in the sand of the seafloor or riverbeds. Clams have two shel ...

, is found. This species was once extremely abundant near the mouth of the Colorado river, but now only exists in a few isolated places. The decline of this clam is explained by the increase in salinity of the water due to diversion of and use of water from the Colorado river.

Energy resources

In 1981, Pemex discovered

natural gas Natural gas (also called fossil gas or simply gas) is a naturally occurring mixture of gaseous hydrocarbons consisting primarily of methane in addition to various smaller amounts of other higher alkanes. Low levels of trace gases like carbo ...

near the island, prompting a scramble for oil and gas leases in the nearby city of

Yuma, Arizona Yuma ( coc, Yuum) is a city in and the county seat of Yuma County, Arizona, United States. The city's population was 93,064 at the 2010 census, up from the 2000 census population of 77,515. Yuma is the principal city of the Yuma, Arizona, M ...

."Find prompts scramble", ''The Courier'', Vol. 90, No. 152, Aug 4, 1981.
/ref> The area has also been studied for the potential use of

tidal power Tidal power or tidal energy is harnessed by converting energy from tides into useful forms of power, mainly electricity using various methods. Although not yet widely used, tidal energy has the potential for future electricity generation. Ti ...

References

{{Coord, 31, 44, 18, N, 114, 44, 47, W, source:INEGI_scale:500000, display=title Islands of Mexicali Municipality Islands of the Gulf of California Islands of the Colorado River Lower Colorado River Valley Nature reserves in Mexico Protected areas of Baja California San Luis Río Colorado Municipality, Sonora Steamboat transport on the Colorado River