Falaschi Mattia, Lo Parrino Elia, Manenti Raoul, Ficetola Gentile Francesco
Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy.
Laboratoire d'Écologie Alpine, Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, Grenoble, France.
Conserv Biol. 2025 Aug;39(4):e70020. doi: 10.1111/cobi.70020. Epub 2025 Mar 28.
Temporal trends in populations are often measured with presence-absence and abundance data. These data types are inherently different, but quantitative comparisons of threat statuses assessed through occupancy or abundance data are currently lacking. We applied International Union for Conservation of Nature (IUCN) criteria to estimate extinction risk of amphibians on the basis of data collected over 25 years. We examined whether occupancy and abundance models provided consistent threat status. Occupancy and abundance data suggested declines for the study species in the study area, but occupancy generally showed smaller proportional changes compared with abundance data. Abundance data yielded higher threat categories than occupancy data but were generally associated with larger uncertainties. With abundance data, population declines were found sooner than with occupancy data, but occupancy data estimates were more robust; thus, we advocate the integration of multiple measures of decline when assessing threat status.
种群的时间趋势通常通过存在-缺失和丰度数据来衡量。这些数据类型本质上是不同的，但目前缺乏通过占有率或丰度数据评估的威胁状态的定量比较。我们应用国际自然保护联盟（IUCN）的标准，根据25年来收集的数据来估计两栖动物的灭绝风险。我们研究了占有率和丰度模型是否提供一致的威胁状态。占有率和丰度数据表明研究区域内的研究物种数量有所下降，但与丰度数据相比，占有率的比例变化通常较小。丰度数据得出的威胁类别高于占有率数据，但通常伴随着更大的不确定性。与占有率数据相比，丰度数据能更快发现种群数量下降，但占有率数据的估计更可靠；因此，我们主张在评估威胁状态时整合多种下降指标。
