teau. The terrain is flat to gently rolling and is dissected by many rivers that drain into the Atlantic Ocean. Elevations inland reach 150 m and drop toward the coast. Annual rainfall ranges from 1,000–1,500 mm, mostly falling during a 6-month period every year; then the region goes through 5–6 months of drought. Annual temperature ranges from 25°–28°C. The bottomland soils are rich from river deposits of different materials.
The most striking features of the region are the extensive high-density stands of the economically important oil palm babassu. While the palm is native to the ecoregion, human activities in primary forests including burning and deforestation, from which this species is adapted to recover quickly, have assisted its spread to become the predominant vegetation. Abundant trees of primary forest include yellow mombin, membrillo, suradan, and Protium heptaphyllum (used for incense).
This ecoregion originally supported a collection of rare endemic birds, fishes, and insects. Habitat degradation of the area has caused reduced the biodiversity. There are still 112 mammals recorded such as the lowland paca, agouti, Brazilian porcupine, spiny rats, and hog-nosed skunks. Around 268 bird species have been recorded as well.
About half of this ecoregion is covered by secondary forest and degraded pasture. No large protected areas exist here. Severe deforestation during the past 70 years has eliminated most of the original moist forest, and only remnant patches remain. The babassu palm continues to proliferate on deforested sites, which are in great supply as human activities such as agriculture and ranching require cleared land.
The remnants of natural savanna and forest vegetation are threatened by strong demand for land for large-scale intensive production operations, such as cattle-ranching and sugar cane plantation. Introduced grasses for pasture such as Hyparrhenia rufa compete with native savanna species. All these factors increase the stress on the original moist forest habitat and lead to further 