Comparative Bird Community Assessments in Grassland, Shrubland, and Woodland Habitats at the Sevilleta National Wildlife Refuge, New Mexico (1991-1997 and 2022-2023)

Across North America, avifauna abundance has declined by 30% since
1970 (Rosenberg, K.V. et al. 2019). Direct mortality from
anthropogenic sources (pets, cars, collisions with building, power
lines, wind turbines, etc.) and indirect mortality (habitat loss,
disturbance, climate change, etc.) have both been major contributors
to these declines (Loss, S.R. et al. 2015 and Calvert, A.M. et al.
2013). Variables such as migration patterns, family, breeding and
non-breeding biomes show differing rates of decline (Rosenberg, K.V.
et al. 2019). In New Mexico, there are three breeding biomes all
classified with declining avian abundance. Avian abundance in
grasslands has declined by 53.3% since 1970, western forests by
29.5% and arid lands by 17.0% (Rosenberg, K.V. et al. 2019). All
three of these biomes also occur at the Sevilleta National Wildlife
Refuge thus temporal declines in species richness and abundance are
expected. This project was originally designed to sample the species
richness and abundance of birds on the Sevilleta National Wildlife
Refuge in three types of habitat: grassland, creosote shrubland and
pinyon-juniper woodland. Surveys were conducted between January 1991
and May 1997 (Parmenter, R. 2016). Surveys were re-established in
2022 to document current species richness and abundance and to
capture any temporal changes from the 90s data. Avian point count
survey stations in grassland, creosote and pinyon-juniper habitats
run through existing study sites which have all been subjected to
intense research activity. Literature Cited A. M. Calvert, C. A. Bishop, R. D. Elliot, E. A. Krebs, T. M. Kydd,
C. S. Machtans, G. J. Robertson, A synthesis of human-related avian
mortality in Canada. Avian Conserv. Ecol. 8, art11 (2013).
https://www.ace-eco.org/vol8/iss2/art11/ Loss, S. R., Will, T., Marra, P. P. 2015. Direct Mortality of Birds
from Anthropogenic causes. Annu. Rev. Ecol. Evol. Syst. 46, 99–120.
https://www.annualreviews.org/doi/10.1146/annurev-ecolsys-112414-054133 Parmenter, R. 2016. Bird Community Assessment in Grassland,
Shrubland, and Woodland Habitats at the Sevilleta National Wildlife
Refuge, New Mexico (1991-1997) ver 120281. Environmental Data
Initiative.
https://doi.org/10.6073/pasta/3beb1560512426422d81806084a1f56b
(Accessed 2021-09-14). Rosenberg, K.V., Dokter, A.M., Blancher, P.J., Sauer, J.R., Smith,
A.C., Smith, P.A., Stanton, J.C., Panjabi, A., Helft, L., Parr, M.,
Marra, P.P. 2019. Decline of the North American avifauna. Science,
366(6461), 120-124.
https://www.science.org/doi/full/10.1126/science.aaw1313

自1970年以来，北美地区的鸟类群落（avifauna）种群丰度已下降30%（Rosenberg, K.V. 等，2019）。人为来源的直接死亡（包括宠物侵扰、车辆撞击、建筑碰撞、输电线碰撞、风力涡轮机碰撞等）与间接死亡（包括栖息地丧失、人类干扰、气候变化等）均是导致种群下降的主要诱因（Loss, S.R. 等，2015；Calvert, A.M. 等，2013）。迁徙模式、鸟类类群、繁殖与非繁殖生物群系（biome）等变量会导致不同类群的种群下降速率存在差异（Rosenberg, K.V. 等，2019）。

新墨西哥州境内存在三类均出现鸟类丰度下降的繁殖生物群系：草原的鸟类丰度自1970年以来下降53.3%，西部森林下降29.5%，干旱地带下降17.0%（Rosenberg, K.V. 等，2019）。上述三类生物群系均分布于塞维利塔国家野生动物保护区（Sevilleta National Wildlife Refuge），因此该区域的物种丰富度与鸟类种群丰度预计也会出现随时间推移的下降趋势。

本项目最初旨在针对塞维利塔国家野生动物保护区内三类生境开展鸟类物种丰富度与种群丰度的采样调查，分别为草原（grassland）、拉雷亚灌丛（creosote shrubland）与矮松-桧柏林地（pinyon-juniper woodland）。调查于1991年1月至1997年5月间开展（Parmenter, R.，2016）。2022年项目组重新启动调查，以记录当前的鸟类物种丰富度与种群丰度，并对比1990年代的调查数据以捕捉时间维度上的种群变化。

本次鸟类样点计数调查（avian point count survey）的站点设置于草原、拉雷亚灌丛与矮松-桧柏林地的现有研究样地中，这些样地均已开展过大量高强度的研究工作。

参考文献
1. Calvert, A. M., Bishop, C. A., Elliot, R. D., Krebs, E. A., Kydd, T. M., Machtans, C. S., Robertson, G. J. 加拿大人类活动相关鸟类死亡研究综述. 《Avian Conservation and Ecology》, 8, art11 (2013). https://www.ace-eco.org/vol8/iss2/art11/
2. Loss, S. R., Will, T., Marra, P. P. 2015. 人为因素导致的鸟类直接死亡. 《Annual Review of Ecology, Evolution, and Systematics》, 46, 99–120. https://www.annualreviews.org/doi/10.1146/annurev-ecolsys-112414-054133
3. Parmenter, R. 2016. 新墨西哥州塞维利塔国家野生动物保护区草原、灌丛与林地生境的鸟类群落评估(1991-1997) 版本120281. 环境数据倡议组织. https://doi.org/10.6073/pasta/3beb1560512426422d81806084a1f56b (2021年9月14日访问)
4. Rosenberg, K.V., Dokter, A.M., Blancher, P.J., Sauer, J.R., Smith, A.C., Smith, P.A., Stanton, J.C., Panjabi, A., Helft, L., Parr, M., Marra, P.P. 2019. 北美鸟类种群的衰退. 《Science》, 366(6461), 120-124. https://www.science.org/doi/full/10.1126/science.aaw1313