**5. Conclusion**

In conclusion, I present evidence that greater rheas have been adapting well to man-made landscapes and is of minor relevance regarding conservation in most

*Birds - Challenges and Opportunities for Business, Conservation and Research*

from their natural habitat in the savannas bordering the Amazon Forest.

expansion of soybean farming. They are also found on degraded pasture, expanding

Extinctions of greater rhea happened over much of the savannas (Cerrado ecoregion) within the state of southeastern Brazil, as Minas Gerais and São Paulo. Both states have lost their rheas populations in areas where intensive agriculture—as sugarcane, eucalyptus and other non-open field crops—have been implemented. Hundreds of years of unregulated hunting, together with poaching after Brazil established wildlife protection laws, may also have presented a role over these range contractions.

Greater rheas are present over much of their historical range, successfully adapting to human-modified landscapes. This adaptability allowed greater rheas to expand their range naturally, and thrive after introductions. Citizen-science databases continue to prove their usefulness, providing up-to-date data on species distribution that would be unfeasible if provided by traditional field-collection activities. Even after trimming, hundreds of recent records of greater rheas are readily available. Those records allow us to infer that the species continues to be present over much of its historical range over South America's "diagonal of dry areas". Additionally, they have been introduced into several spots at coastal Brazil, where some populations thrive. Besides these, large-scale range expansions exist in several parts of their range, with emphasis on the Amazon Forest. Those results are

One first element I call into attention is about the global status of the greater rhea at IUCN: the species is currently considered Near Threatened [29]. Pointing habitat loss as a problem seems a mistake, since the species is expanding range, including both soybean plantations and degraded pastures as habitat. Evidence towards this can be drawn from the fact that the species still presents big populations even within sections of central Brazil that have been dominated by farming (as Goiás state), where greater rheas subsist between cultivated fields, pastures and private reserves (as required by Brazil forest code [41]). On the other hand, poaching in northeastern Brazil seems to have limited the populations in Caatinga [42]. Since this is one of the poorest regions of Brazil [43], and at the same time one of the arid region of highest population density on Earth [44], the underlying reasons become obvious. This is especially worrisome because these animals appear to be under relatively isolation regarding the populations on Cerrado, and have potential to represent a subspecies endemic to the arid lands of Northeastern Brazil. Whereas they have been under the name of *R*. *a*. *americana* under old-fashioned taxonomy [45], this topic deserver further attention. The species global range and threat status

On the other hand, greater rheas have disappeared from several important protected areas in Brazil, which have been curiously less efficient in maintaining populations than the aforementioned private lands. Some of the more emblematic examples come from: (i) Águas Emendadas Ecological Station and Brasília National Park, both well-managed protected areas in Brazil capital where feral dogs and poaching eliminated the species [46]; (ii) Serra da Capivara National Park, where poaching and woody-vegetation encroaching eliminated the species [42]; and (iii) the Itirapina Ecological Station, where the reasons also seems related with poaching and feral dogs [47]. A tantalizing historical record of the species—which have been putatively attributed to Campos dos Goytacazes—is presented on an illustration at Rugendas *Magnum Opus* "*Malerische Reise in Brazilien*" [48]. Campos dos Goytacazes presents open habitat enclave in within the Atlantic Forest dense

of prime importance for the species management and conservation.

**118**

deserves a reevaluation.

**4. Discussion**

of its range. Populations within Caatinga in northeastern Brazil are an exception regarding this trend. Additionally, the species have expanded its range, most expressively in the Amazon forest, with unknown consequences. Introductions in several restinga locations also exist. Additionally, the species present potential as game, and this can contribute to their conservation. Finally, the open landscapes within South America are important refuges for the greater rhea, an under-studied, emblematic species of the savannas region in the Neotropics.
