This EBA embraces the Gulf of Mexico coastal plain of north-east Mexico in the states of Tamaulipas and northern Veracruz, and adjacent Nuevo León and San Luis Potosí; the plain is widest in the north and narrows markedly southwards. The landward boundaries of the EBA are the Bravo river to the north, the edge of the foothills of the Mexican plateau and the Northern Sierra Madre Oriental (EBA 010) to the west, and the Southern Sierra Madre Oriental (EBA 012) to the south.

There is a wide variety of vegetation types in this EBA, but tropical deciduous forest and scrub predominates, with semi-evergreen forest in humid canyons, and extensive coastal lagoons.

All four restricted-range species of the EBA are confined to it. Geothlypis flavovelata is restricted to freshwater marshes and reedbeds, but the other three occupy a variety of mainly forest habitats though they occur widely also in open country and agricultural land.

The natural habitats present within this EBA have been heavily modified in this now largely agricultural region where cattle-ranching is the predominant activity. Extensive areas of deciduous and semi-deciduous forest have become rare, and are mainly confined to the foothills on the western side of the EBA.

All of the restricted-range species appear to be able to persist in degraded lands. However, Amazona viridigenalis is considered threatened because it has gone from being a common and widespread species a few decades ago to being a generally rare bird today. The reason for this decline is a combination of extensive habitat loss and overexploitation for the cage-bird trade. The current wild population is judged to be 3,000-6,500 birds, and illegal trade continues, with no adequate protection of its habitat (E. C. Enkerlin in litt. 1994).

Part of the range of the Atlantic lowland race magna of the widespread Yellow-headed Amazon Amazona oratrix (classified as Endangered) is found within this EBA. The species, which is the most popular and sought-after amazon in trade, co-occurs with A. viridigenalis at four sites listed by Wege and Long (1995) as Key Areas for the protection of threatened species: Los Colorados Ranch (8 km²), a privately owned ranch of southern Tamaulipas, where, although 80-85% of the land is cleared for cattle pasture, many large trees remain and both threatened Amazona species breed, with more than 100 nests found there during a recently completed five-year study (Enkerlin 1995); Soto La Marina/La Pesca, lying at sea-level in eastern Tamaulipas, holding small but stable populations of both the threatened Amazona; Río el Naranjo, centred on Las Abritas village in north-central San Luis Potosí, consisting mainly of humid oak-sweetgum forest, where A. viridigenalis nests but A. oratrix is probably only an uncommon resident; and the El Cielo Biosphere Reserve (1,445 km²), centred on the Rancho Rinconada and the Río Frío districts, and located on the lower Atlantic slopes of southern Tamaulipas. The latter reserve holds one of the most extensive tracts of pristine deciduous and semi-deciduous forest, as well as montane forest at higher altitudes. Both threatened Amazona occur, as well as the widespread Military Macaw Ara militaris (Vulnerable) , as do the other restricted-range species inhabiting woodlands.

Recommended citation
BirdLife International (2024) Endemic Bird Area factsheet: North-east Mexican Gulf slope. Downloaded from https://datazone.birdlife.org/eba/factsheet/7 on 23/11/2024.