Parque Regional Lomas de Arena: An Atlas of Inland Dunes and Transitional Chaco Forest Landscapes

The origins of Lomas de Arena trace to a youth-led conservation campaign in the late 1980s. The Unión Juvenil Cruceñista launched what contemporary press called a 'Crusade for Lomas de Arena,' advocating for the protection of the area's dune ecosystem, its Chané archaeological remains, and the agricultural lands of nearby Mennonite communities.

In response, the Unidad Técnica Desconcentrada del Centro de Desarrollo Forestal de Santa Cruz issued a founding resolution on 6 June 1989, with the park formally created on 7 September 1990. An inter-institutional governing board was established, including the forestry authority, the Comité Pro Santa Cruz, the Universidad Autónoma Gabriel René Moreno, and the Instituto Geográfico Militar.

The board then pursued formal national recognition, resulting in Supreme Decree N° 22911 of 25 September 1991, which cemented the park's protected status. About a decade after creation, administration passed to the Prefectura del Departamento, now the Gobierno Autónomo Departamental de Santa Cruz, which partnered for a five-year period with the Fundación Simón Iturri Patiño before returning full management to the departmental government under the supervision of an inter-institutional management committee.

Ecologically, Lomas de Arena sits at an important transition zone between the Chaco and the lowland savannas and forests of eastern Bolivia. The site protects representative samples of bosque húmedo transicional chaqueño, or transitional humid Chaco forest, alongside natural savannas that are increasingly rare in the surrounding agricultural landscape.

The vegetation mosaic serves multiple ecological roles. Forest patches stabilize the dune system by anchoring sand, while savanna areas support open-ground species and grazing dynamics. The main lagoon and associated wetlands add an aquatic dimension that supports amphibians, reptiles, and waterbirds, linking the terrestrial habitats into a more cohesive ecosystem.

The protected botanical inventory includes around 208 species of vascular plants. Notable species include the toborochi (Chorisia), tajibo, curupaú (Anadenanthera colubrina), motacú, totaí, and various cactus species adapted to the sandy soils and drier patches within the dune system.

The park's mosaic of forest, savanna, dunes, and wetland supports a notable variety of fauna. A special highlight is the presence of the Pichiciego Mayor, or greater fairy armadillo (Calyptophractus retusus), a rare small armadillo adapted to sandy habitats and one of the more distinctive species associated with the park.

Mammal diversity is broad for an area of this size. Recorded species include opossums, anteaters, sloths, at least 12 species of bats, monkeys such as the martín, as well as meleros, tejones, foxes, jochis, urinas, and taitetú. The reptile and amphibian fauna is also significant, with around 50 reptile species, including roughly 27 amphibian species documented within the park.

The birdlife is a major draw and one of the most important biodiversity indicators for the site. Roughly 286 bird species have been recorded, representing about 21 percent of all birds reported for Bolivia. Notable species include the pava campanilla (Pipile cumanensis), the paraba roja or scarlet macaw (Ara macao), and the bato (Bartramia longicauda).

Lomas de Arena is significant for conservation because it safeguards a fragile dune-forest ecosystem embedded in a heavily modified agricultural matrix. Studies in the park, including work referenced from 1997 onward, have classified its forest condition as vulnerable, highlighting the importance of continued protection for the soils, vegetation cover, and biodiversity of the area.

The forest stands are central to the park's ecological functioning: they stabilize dune movement, provide habitat and food for wildlife, preserve scenic value, and prevent desertification that could spread into surrounding productive lands. Yet the protected area is composed entirely of private properties with established agricultural and livestock traditions, which complicates enforcement and makes incremental deforestation a persistent risk alongside fire and land conversion.

The park's IUCN Category V status frames conservation as compatible with traditional land use and recreation rather than as strict exclusion. Through its departmental management, inter-institutional oversight, partnership history with the Fundación Simón Iturri Patiño, and recent interpretive center, the site represents an important example of lowland Bolivia attempting to maintain ecosystem services, cultural heritage, and rural livelihoods within a single protected framework.

The park carries cultural meaning on several levels. It contains the only formally identified archaeological site of the Chané culture within the protected landscape, located in a sector known as Los Chivatos, where ceramics and cemetery remains have been recovered.

In modern regional life, Lomas de Arena functions as a major weekend and family recreational landscape for residents of Santa Cruz de la Sierra and nearby La Guardia. Activities such as carriage rides along an approximately five-kilometer ecological trail, horseback excursions, and visits to private rural quintas (recreational farms) tie the park to long-standing traditions of countryside leisure in the lowlands.

The conservation campaign of the late 1980s, launched by the Unión Juvenil Cruceñista and backed by civic groups and the Universidad Autónoma Gabriel René Moreno, also reflects a regional identity built around protecting local natural landmarks as part of Cruceño cultural heritage.

Lomas de Arena stands out for the unusual pairing of an inland dune field with stabilizing Chaco forest and savanna, producing a beach-like landscape deep in the Bolivian lowlands. The presence of the rare greater fairy armadillo and the unusually high regional bird diversity add strong nature-watching value.

The site's combination of Chané archaeological heritage, traditional rural quintas, ecological trail experiences, and a recently inaugurated interpretation center gives it layered appeal for visitors interested in ecology, history, and regional culture at once.

The park enjoys a tropical lowland climate tied to the wet and dry seasons of the Santa Cruz region. The dry months, roughly coinciding with the southern winter, typically offer the most reliable access, clearer skies for dune scenery, and easier conditions for trails, carriage rides, and beach-style recreation on the sands.

The wet season brings more greenery and bird activity, including migrant species, but also turns tracks to mud and can make the dune and rural access roads more challenging. Visitors oriented toward photography, dune trekking, and family beach days generally favor the dry months, while bird-focused visits can benefit from the wetter period when waterbirds and seasonal migrants are active.