Animal traditions are increasingly threatened by human impact on natural habitats, posing a challenge to conservation policies. In northeastern Brazil, bearded capuchins (Sapajus libidinosus) inhabiting the Cerrado–Caatinga biome of Fazenda Boa Vista use stone hammers and anvils to crack open palm nuts and other encased foods. The same species inhabiting the mangroves of Morro do Boi ambush crabs and process them using wooden hammers and anvils. These traditions are gradually acquired by young capuchins exposed to the tool using activity of skilled older group members. Changes in land cover have threatened the persistence of this species, where these rare tool-use traditions occur. To assess land cover changes over the past 30 years, we analyzed a time series of remotely sensed imagery and quantified trends in land cover and agriculture across both study sites. We also developed a predictive model to forecast future changes in land cover by 2034. Our results show that agriculture increased by more than 300% in both sites from 1987 to 2017. If current trends continue in Morro do Boi, only 42% of forest (0.15 km2) will remain, which is insufficient to support the resident population of capuchins. In Fazenda Boa Vista, most of the land suitable for agriculture has already been used for that purpose. If private conservation efforts at Fazenda Boa Vista are to be effective through 2034, agricultural use should not be expanded any further. Imminent erosion and loss of natural vegetation will exacerbate the current situation, even if agriculture is not expanded. Our study is an example of the need for conservation to take behavioral traditions into account, as they are not widespread across the species distribution.

中文翻译：

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稀有胡子卷尾猴 (Sapajus libidinosus) 工具使用文化受到巴西东北部土地利用变化的威胁

人类对自然栖息地的影响日益威胁到动物传统，这对保护政策构成了挑战。在巴西东北部，栖息在 Fazenda Boa Vista 的 Cerrado-Caatinga 生物群落中的胡须卷尾猴 (Sapajus libidinosus) 使用石锤和铁砧敲开棕榈果和其他包裹的食物。栖息在 Morro do Boi 红树林的同一物种会伏击螃蟹并使用木锤和铁砧加工它们。这些传统是由年轻的卷尾猴通过熟练的老年群体成员的活动逐渐获得的。土地覆盖的变化威胁到这个物种的生存，这些罕见的工具使用传统发生在那里。为了评估过去 30 年的土地覆盖变化，我们分析了两个研究地点的遥感图像和量化趋势的时间序列。我们还开发了一个预测模型来预测到 2034 年土地覆盖的未来变化。我们的结果表明，从 1987 年到 2017 年，两个地点的农业增长了 300% 以上。如果 Morro do Boi 目前的趋势继续下去，只有 42% 的森林（ 0.15 平方公里) 将保留，这不足以支持卷尾猴的常住人口。在 Fazenda Boa Vista，大部分适合农业的土地已经用于该目的。如果 Fazenda Boa Vista 的私人保护工作要在 2034 年之前有效，就不应进一步扩大农业用途。即使不扩大农业，迫在眉睫的侵蚀和自然植被的丧失也会加剧目前的情况。