Assessing the effects of Close-to-Nature Forestry on forest birds in the eastern United States: A case study and way forward

Abstract

Over the last half-century, North American forest birds have experienced staggering declines, while at the same time, many metrics indicate that North American forest health has improved. While the United States has been recognised for global leadership in innovation and research in forestry, the negative impacts of high-severity harvesting methods and forest fragmentation are sometimes overlooked, and a dearth of research studies exist that assess the impacts of lower-severity forestry practices on birds. Globally, some regions are pursuing markedly different forestry practices, and one example is Europe’s Close-To-Nature Forestry (CTNF) that protects forest canopies. Historically, CTNF methods have not been promoted to help avian abundance or diversity; however, forest bird populations in Europe have increased 7% over the last two decades, and we posit whether similar forest management approaches in the eastern USA could benefit North American birds. Therefore, we sought to 1) assess the effects of forest structural characteristics on avian species richness in a CTNF-managed forest in the eastern USA; 2) compare our results to county-level eBird data to identify the challenges of assessing the impacts of forestry practices on birds at landscape scales; 3) highlight the ambiguities in current forest management guidelines for improving avian habitats in the USA and 4) suggest long-term direction for evaluating the impacts of alternative forest management practices on birds. Our case study provides preliminary evidence that CTNF-managed forests may support diverse birds of high conservation value that are normally drawn to different forest management extremes. We also provide recommendations for utilising eBird data to assess alternative forest management strategies at landscape scales and a synthesised look at the forest management guidelines provided by many of the major players in American ornithology. While there may be multiple reasons for forest bird declines noted in the past 50 years in North America, long-standing forest management practices and policies should not be overlooked.