State of Piauí

Piauí is one of the twenty-seven states of Brazil, located in the northeastern part of the country. It covers an area of 251,529 km² (97,116 square miles) and has a population of around 3.3 million people. Almost a third live in the state capital, Teresina. It is bounded on the west by Maranhão, and has a tiny border with Tocantins in the southwest. To the northeast lies Ceará, to the east Pernambuco and to the southeast Bahia. It has a few miles of Atlantic coastline to the north – the shortest coastline of any of the non-landlocked Brazilian states at just 66 km (41 miles), and Teresina, is the only state capital in the north east to be located inland. The reason for this is, unlike the rest of the area, Piauí was first colonised inland and slowly expanded towards the ocean, rather than the other way around.

The Parnaíba River forms the boundary with Maranhão throughout its entire length. The state lies almost entirely within the basin of the Parnaíba and its tributaries. The part of the state on the Atlantic coast and along the lower Parnaíba is low, swampy, and historically malarial. South of this the country rises gradually to a high plateau with open campos.

Rio Parnaíba – ©Fabiobarros CC BY-SA 4.0 via Wikimedia Commons

This plateau region is watered by numerous tributaries of the Parnaíba, chief of which are, from south to north: The Poti, which has its source in the state of Ceará; the Longa; the Canindé and its tributary the Piauí; the Gurguéia and its tributary the Parahim, which drains the large inland lake of Parnagua; and the Uruçui-Preto. The Parnaíba is navigable for boats of 1 meter draft up to Nova York, a few miles above the mouth of the Gurguéia. The river valleys are separated by flat-topped plateaus called chapadas. These include the Serra Uruçui, which lies between the Uruçui-Preto and the Gurguéia; the Serra da Capivara National Park – a UNESCO World Heritage Site, which lies between the Gurguéia and the Piauí; and the Chapada das Mangabeiras, which forms the southwestern boundary of the state, separating the upper basin of the Parnaíba from that of the Tocantins. Serra da Capivara NP has more than 400 archaeological sites and the largest concentration of rupestrian (rock) paintings on the planet, in a landscape dominated by canyons and caatinga.

The climate is hot and humid in the lowlands and along the lower Parnaíba, but in the uplands it is dry with high day temperatures and cool nights. The sandy soils along the Atlantic coast are home to the Northeastern Brazil restingas, low evergreen forests adapted to the nutrient-poor conditions. The lower basin of the Parnaíba is home to the Maranhão Babaçu forests, which extend westward into Maranhão. This ecoregion is dominated by stands of the Babaçu palm.

Serra da Capivara National Park – ©LeonardoRamos CC BY-SA 4.0 via Wikimedia Commons

The eastern portion of the state is dominated by the dry Caatingas shrublands, which extend across much of northeastern Brazil. The Cerrado savannas extend across the southwestern portion of the state, in the basins of the upper Parnaíba and Gurguéia rivers. Enclaves of Atlantic dry forests lie in basin of the Gurguéia, forming a transition between the Cerrado and Caatinga.

Birding Piauí

Serra da Capivara National Park provides a stunning semi-arid landscape of dry shrubs typical of the dry northeastern biome, which is home to many of Brazil’s northeast iconic species. It can be good for Lear’s & Indigo Macaws, Moustached Woodcreeper, Black-chested Buzzard-Eagle, Caatinga Antshrike, Pygmy Nightjar and the extremely rare Araripe Manakin.

The caatinga is not the only habitat in the state. For example, the Delta of the Parnaíba River is located on the border of Maranhão and Piauí, and features lagoons, desert dunes and deserted beaches or islands, such as the Caju island, which shelters a number of rare birds.

Delta do Parnaíba – ©Gabriel P Silva CC BY-SA 4.0 via Wikimedia Commons

Another hot spot is Castelo do Piauí that features transition vegetation in the rocky outcrops of sandstone which, again is good for dry forest and scrub birdlife.

Parque da Cidade is the state capital’s best urban green space as it records high frequencies of regional species like the Buff-browed Chachalaca and Crested Oropendola.

A 4,200-hectare protected zone called the Hyacinth Cliffs Reserve near the Parnaíba Park is known for local raptors and cliff-dwelling species.