Land clearing of habitat into smaller, isolated remnants is a major driver of plant and animal extinctions globally. In southeastern Australia, once widespread temperate savannas have been subjected to extensive land clearing since European settlement. Some small fragments have persisted, but declines in the dominant trees have been reported, with anecdotal observations of widespread recruitment bottlenecks and seed set failure. To test the hypothesis that populations of Banksia marginata are experiencing widespread recruitment bottlenecks, we examined tree size-class distribution and production of infructescences (cones) of 15 populations on the western plains of Victoria, Australia. We found no evidence of widespread recruitment bottlenecks or a failure to set seeds; most populations were recruiting, though we did find evidence of declining recruitment with population size, suggesting evidence of an Allee effect. The proportion of trees without cones varied between populations; three populations had large numbers of trees (> 40%) lacking mature fertile cones. Managers should focus on minimising threats to seedling survival and augment populations below 100 individuals to improve recruitment and maintain stand persistence in the landscape.

将栖息地的土地清理成较小的，孤立的残余物是全球动植物灭绝的主要动力。在澳大利亚东南部，自欧洲定居以来，曾经广泛分布的温带热带稀树草原已经遭到广泛的土地清理。仍然存在一些小碎片，但据报道主要树木的衰落，从传闻中发现广泛的招聘瓶颈和结实种子失败。检验Bank木种群的假设正经历着广泛的招聘瓶颈，我们研究了澳大利亚维多利亚州西部平原上15个种群的树木大小等级分布和花序（圆锥）的产生。我们没有发现广泛的招聘瓶颈或未能建立种子的证据。大多数人口都在招募人员，尽管我们确实发现了随人口规模而减少的招募证据，这表明有阿利效应的证据。无锥果树的比例因种群而异。3个种群的树木大量（> 40％）没有成熟的肥沃球果。管理人员应集中精力减少对幼苗生存的威胁，并增加100个以下的种群，以提高招聘人数并保持林分持久。