SummaryThe Giant Nuthatch Sitta magna is a globally endangered species presumed to be declining, for which basic parameters of population and habitat associations remain largely unquantified. We focused on Myanmar, which potentially constitutes ~30% of the Giant Nuthatch global range and yet lacks recently published records. Our objectives were to survey key potential Giant Nuthatch localities in, or near, historical locations in Southern Shan State, assess its population status, and quantify habitat associations. Preliminary locality surveys focused on four potential forest patches, assessed by walking approximately 40 km of trails. The species was found in only one of the four localities (Mt. Ashae Myin Anauk Myin [AMAM]), an 18 km2 forest patch in Pindaya and Lawksawk Townships. Here, point counts and vegetation surveys were conducted at 46 locations using an adaptive cluster sampling design. N-mixture models were applied to estimate abundance and identify habitat variables correlated with abundance and detection probability. We also conducted a brief quantitative assessment of tree use and foraging behaviour during one breeding season. Our population estimate for AMAM was 56 individuals (95% CI 25–128) based on a sampled area of 3.25 km2. Abundance was positively associated with larger diameter trees, a higher proportion of pine and oak combined based on their total basal area, and negatively correlated with elevation. Foraging data suggested that Giant Nuthatch preferred to feed on trunks and large branches of larger diameter pines and Fagaceae trees. Based on the estimated population size, AMAM is probably a globally significant locality for Giant Nuthatch and the only confirmed locality in Myanmar since 1992 but is threatened by agricultural expansion. More detailed understanding of the habitat requirements of this endangered species and an assessment of its distribution at the landscape-level, especially in Shan State, would increase the precision of global population estimates.

中文翻译：

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缅甸南部掸邦全球濒临灭绝的巨型五子雀 Sitta magna 的丰度和栖息地关联

摘要巨型五子雀西塔麦格纳是一种假定正在减少的全球​​濒危物种，其种群和栖息地关联的基本参数在很大程度上仍未量化。我们专注于缅甸，它可能构成巨型五子雀全球范围的约 30%，但缺乏最近公布的记录。我们的目标是调查南掸邦历史位置内或附近的主要潜在巨型五子雀地点，评估其人口状况，并量化栖息地关联。初步的地点调查集中在四个潜在的森林斑块上，通过步行约 40 公里的小径进行评估。该物种仅在四个地区之一（Mt. Asae Myin Anauk Myin [AMAM]）被发现，全长 18 公里2Pindaya 和 Lawksawk 镇的森林斑块。在这里，使用自适应整群抽样设计在 46 个地点进行了点数和植被调查。应用 N 混合模型来估计丰度并确定与丰度和检测概率相关的栖息地变量。我们还对一个繁殖季节的树木使用和觅食行为进行了简短的定量评估。基于 3.25 平方公里的采样区域，我们对 AMAM 的人口估计为 56 人（95% CI 25-128）2. 丰度与较大的树径、较高的松树和橡树总基面积比例呈正相关，与海拔呈负相关。觅食数据表明，巨型五子雀更喜欢以较大直径的松树和镰刀科树的树干和大枝为食。根据估计的人口规模，AMAM 可能是 Giant Nuthatch 的全球重要地点，也是自 1992 年以来缅甸唯一确认的地点，但受到农业扩张的威胁。更详细地了解这种濒危物种的栖息地需求并评估其在景观层面的分布，特别是在掸邦，将提高全球人口估计的准确性。