Mammal Diversity and Ecological Corridors in the Cerrado

Research included:

Mapping Cerrado vegetation and habitat types.

Surveying the diversity of Cerrado mammals and their habitat use (using camera traps, sand traps, and line-transect distance sampling).

Identifying areas of the Cerrado with high conservation value, and ecological corridors connecting these areas.

The long-term monitoring of giant otters (Pteronura brasiliensis), including data collection on population dynamics and life history through camera trapping and direct observation.

Aiding in the production of a pan-Amazonian map of areas of high importance to the conservation of giant otters. This involved identifying areas currently utilised by giant otters, unused suitable areas based on biophysical characteristics, and rivers that could become ecological corridors linking these areas. In future, the potential impacts of proposed development projects on giant otters will be assessed using this map.

The death of the world’s most biodiverse savannah is going unnoticed.

Paradoxically, Brazil’s Cerrado is both the biologically richest savannah in the world and vanishing without international outcry. Many of its animals and plants are found nowhere else, and its larger residents are both iconic and endangered: jaguars, giant anteaters, tapirs, and maned wolves. Over the last 35 years, half of the Cerrado has been converted into agricultural land, and less than 20% of the original area remains undisturbed. This loss is ongoing, due to the expansion of both soy and beef production in Brazil. Consequently, the deforestation rate in the Cerrado, and the resultant greenhouse gas emissions, exceed even those of the neighbouring Amazon Rainforest. With just 7.5% of its area protected, the Cerrado surely ranks among the world’s most threatened ecosystems, and yet international condemnation of its destruction has never materialised.

I spent the last three months conducting research in the Cantão State Park, an extraordinary transitional zone in which the Amazon Rainforest meets the Cerrado. The park protects seasonally flooding Amazonian forest and its inhabitants, including giant otters and Araguaia river dolphins. However, the adjacent patches of Cerrado are only protected by the goodwill of the local population. These few patches are disproportionately important to the park’s forest wildlife, as they provide a vital dry refuge when the Amazon floods. A reverse migration occurs in the dry season when water and food are limited in the Cerrado but abundant in the forest. This seasonal back-and-forth between the Amazon and the Cerrado underpins the exceptional biodiversity of the region and has allowed the local jaguars to grow larger than any in the Amazon.

The Cerrado itself is a biodiversity hotspot; home to over 4,800 plant and vertebrate species that are found nowhere else, and a grand total of over 7000 plant species: the richest flora of any of the world’s savannahs by a wide margin. On a personal level, a walk in the Cerrado never fails to inspire wonder. A short stroll sees glades of trees with porous cork-like bark give way to grasslands in which exquisite flowers are contrasted with the formidable spiked palms that neighbour them. Insects whose eccentric forms shame the best of Hollywood’s alien creations share this strange world with everything from jaguars and tapirs to anteaters and armadillos. Their numerous footprints are a reminder of just how exceptionally wild this place still is.

In addition to its exceptional conservation value, the Cerrado is an internationally important carbon store, locking up the equivalent of 13.7 billion tons of CO2; much of this is stored below ground, as the plants of the Cerrado have evolved to cope with long dry seasons by developing extensive root systems, which equate for 70% of the total biomass. Sadly, out of sight is out of mind, and approximately 140,000 km2 (an area larger than England) of native vegetation was cleared in the Cerrado between 2006 and 2017, twice the area of vegetation lost in the Amazon during the same period. This exceptional rate of loss has caused the greenhouse gases released due to deforestation of the Cerrado to exceed those released due to deforestation of the Amazon.

Taking into account the services, size, richness, and uniqueness of the Cerrado, its legal protection is disproportionately limited. Only about 7.5% of the Cerrado is legally protected (in comparison with 46% of the Amazon), with less than 3% designated as fully protected conservation area. Additionally, 20% of the threatened animal and plant species endemic to the Cerrado do not occur within these protected areas. This makes the Cerrado one of the least protected global biodiversity hotspots.

I first arrived at the research station along a desolate road bordered by soy plantations that stretched to the horizon; these plantations had been pristine savannah just 5 years earlier. Only the appearance of an occasional rhea broke the monotony of the now monocultured landscape.

Brazil’s Soy Moratorium forbids major trading companies from purchasing soybeans produced on recently deforested areas. It was designed to protect the Amazon from soy cultivation but does not apply to the Cerrado. This meant that in 2015, 48% of Brazil's soybean production was harvested in the Cerrado. Of the remaining Cerrado, 90% is suitable for growing soybeans. If this land is cleared the resultant greenhouse gas emissions will make a tragic joke of Brazil's commitment to international climate and biodiversity conventions. Expanding the Soy Moratorium to the Cerrado is crucial. It has been predicted that its enforcement would save 36,000 km2 of native vegetation from the soy industry over the coming three decades.

The vast majority of Brazil’s soy (82%) goes to China for livestock feed, so pressure from consumers is unlikely to be an effective weapon in the defence of the Cerrado. However, given the extreme anti-environmental stance of Brazil’s current government, international pressure is essential, whether it comes from NGOs, industry, foreign governments, or intergovernmental organizations. As of 2019, 10,000 square kilometres of pristine Cerrado remains. There is still time, but we need to make that time count.