Brazil nut (Bertholletia excelsa Bonpl.) extraction serves as an important economic resource in the Madre de Dios region of Peru simultaneously promoting forest conservation, yet, under current management, it cannot compete with other land uses. This study investigated the effects of logging gaps on Brazil nut natural regeneration. A total of 48 paired logging gap-understory sites were visited in Brazil nut concessions in the Tambopata province of Madre de Dios, Peru. At each site, the number of Brazil nut recruits was counted and canopy openness and gap area were measured. Significantly higher levels of recruit density were found in logging gaps than in understory sites. Additionally, recruit density was positively correlated with canopy openness. Further, in experimental plantings in paired gap and understory sites, canopy openness, height, total leaf area, and number were recorded from August 2011 to February 2012. Height, total leaf area, and leaf number were significantly higher for tree-fall gap grown seedlings, lending further evidence to improved recruitment success of Brazil nuts in forest gaps. These results suggest that multiple-use forest management could be considered as an alternative for the sustainable extraction of Brazil nuts but also highlight that further studies are required. 1. Introduction Brazil nut (Bertholletia excelsa, Bonpl) is a gap-dependent canopy emergent tree requiring high light levels to reach maturity [1, 2] and that relies on scatter-hoarding agoutis (Dasyprocta sp.) to release seeds from the woody pericarp fruit [3]. The long-term demographic viability of Brazil nut populations currently relies on purely natural regeneration. The existing density of mature B. excelsa trees, largely responsible for determining natural regeneration rates, is lower in Madre de Dios, Peru (0.5–1.5 individuals ha？1) [4] than in neighboring Acre, Brazil (1.5–2.5 ind. ha？1) [5] and Pando, Bolivia (2.5–3.0 individuals ha？1) [1]. Commercially, the seeds of B. excelsa (commonly referred to as Brazil nuts) are an economically important nontimber forest product (NTFP) contributing an estimated $8 million USD to Peru’s GDP annually [6], $73 million in Bolivia [7], and $30 million in Brazil [8]. Within Madre de Dios, as much as 22% of the local residents rely directly or indirectly on Brazil nut harvest for their economic livelihoods [9]. The ecological sustainability of Brazil nut extraction is disputed with some researchers alluding to an imminent demographic collapse [10], while others suggest stable populations with current extraction rates
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