Avian population ecology and functional connectivity in managed forest landscapes

最终，自然资源管理影响个体生物。人们通常认为，流动物种的个体会简单地迁移到其他地方，以避免新的干扰区域，但很少有研究来证实这一点。2006年，我们建立了一组试验田，并对一种候鸟（烤鸟）的几乎所有雄性进行了标记，然后在第二年冬天对其中一半的试验田进行了选择收获。这种采伐处理除去了30-40%的木材体积。从那以后，我们一直在监测烤鸟种群和单独标记的雄性的反应。我们还监测了褐爬行鸟的反应，褐爬行鸟是另一种森林鸟类，在研究区域全年居住或短途迁徙。令人惊讶的是，在收获后的第一年，几乎和对照组一样多的雄性灶鸟回到了自己的领地。然而，4年后，在处理过的地块中，来自2006年队列的鸟类的比例仍然低于对照组。我们将继续进行这项研究，以回答以下问题：(1)2006年的烤箱鸟在处理地块的死亡率是否高于对照组？(2)若有，移民是否能维持处理过的田块内灶鸟的密度？(3)这些移民大概来自哪个地区？(4)褐爬行鸟和烤鸟的繁殖成功率是否随巢捕食者的数量而波动，最终是否随种子生产周期而波动？(5)这些现象是否受到采收处理的影响？这两种鸟类目前都不罕见，但它们对其活动范围内的森林都很敏感。因此，这项研究将提供至关重要的信息，以确保设计积极的保护策略，以维持这些物种和生态相似物种的健康种群。如果我们要解决生物多样性丧失的最终原因，预防性研究应该得到与物种恢复同样多的关注。到目前为止，我们的工作已经影响了挪威的森林管理政策，特别是对具有高保护价值的森林进行了描述。

Ultimately, natural resource management influences individual organisms. It is often assumed that individuals of mobile species will simply move elsewhere to avoid newly-disturbed areas but few studies have been conducted to confirm this. In 2006, we established a set of experimental plots and we marked nearly all males of a migratory bird species (Ovenbird) prior to the treatment of half of these plots through selection harvesting during the next winter. This harvest treatment removed 30-40% of the wood volume. We have monitored the response of Ovenbird populations and individually-marked males ever since. We have also monitored the response of the Brown Creeper, another forest bird species that is a year-round resident or short-distance migrant in the study region. Surprisingly, in the first year after harvesting, almost as many male Ovenbirds returned to their territory as in the controls. However, 4 years after, a lower proportion of birds from the 2006 cohort are still present in treated plots than in controls. We will pursue this research to answer the following questions: (1) have the 2006 Ovenbirds suffered a higher mortality in treated plots than in controls? (2) If so, does immigration maintain the density of Ovenbirds in treated plots? (3) What is the approximate region from which these immigrants come from? (4) Does the reproductive success of the Brown Creeper and the Ovenbird fluctuate with the abundance of nest predators and, ultimately, in response to cycles in seed production? (5) Are these phenomena influenced by the harvest treatment? Neither of these bird species is currently rare but both are sensitive to forestry across their range. This research will thus provide information that will be critical to ensure that proactive conservation strategies are designed to maintain healthy populations of these and ecologically-similar species. Preventive research should receive as much attention as species recovery if we are to address the ultimate causes of biodiversity loss. So far, our work has influenced N.B. forest management policy, specifically to characterize forests of high conservation value.