Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, P/Bag X01, Scottsville, Pietermaritzburg, 3209, South Africa.
The Endangered Wildlife Trust, P/Bag X11, Modderfontein, Johannesburg, 1645, South Africa.
Sci Rep. 2020 Oct 1;10(1):16195. doi: 10.1038/s41598-020-73236-4.
Understanding how a species utilises its habitat, and the processes that give rise to its movements and patterns of space use, is critical for its conservation. Southern Ground-hornbills Bucorvus leadbeateri are listed as Endangered in South Africa, as a result of habitat loss and persecution. The National Species Recovery Plan lists reintroductions as a suitable conservation action, but highlights "understanding the exact habitat requirements of Southern Ground-hornbills" as a knowledge gap. In this study, we used tracking data from six Southern Ground-hornbill groups (a total of 37,060 GPS locations) in the Kruger National Park to investigate their seasonal home range differences and habitat preferences. We used first-passage time analysis to determine the scale at which Southern Ground-hornbills concentrate their foraging efforts and whether specific movement behaviours were linked to habitat types. We found marked differences in seasonal home ranges, with all groups showing a range contraction during the breeding season. Grassland and open woodland habitat types were used throughout the year in accordance with their availability within the territory, with grassland, open woodland and dense thicket being favoured habitats for foraging. Our habitat preference results, based on longitudinal GPS data, allowed us to determine ideal habitat ratios (grassland:open woodland:low shrubland of 1.00:6.10:0.09 ha) to assist with the selection of suitable reintroduction sites for Southern Ground-hornbills. With an increasing number of species being threatened with extinction, reintroductions into suitable habitats may be a useful conservation mitigation measure. However, our findings highlight the importance of a thorough understanding of a species' movement and space use prior to the selection of areas for reintroduction to ensure the establishment and sustainability of these species at these sites.
了解物种如何利用其栖息地，以及导致其运动和空间利用模式的过程，对于物种的保护至关重要。南非的南方地犀鸟（Bucorvus leadbeateri）因栖息地丧失和迫害而被列为濒危物种。国家物种恢复计划将重新引入列为合适的保护行动，但强调“了解南方地犀鸟的确切栖息地要求”是一个知识空白。在这项研究中，我们使用了克鲁格国家公园六个南方地犀鸟群体（总共 37060 个 GPS 位置）的跟踪数据，调查了它们的季节性家域差异和栖息地偏好。我们使用首次通过时间分析来确定南方地犀鸟集中觅食努力的规模，以及特定的运动行为是否与栖息地类型有关。我们发现季节性家域存在明显差异，所有群体在繁殖季节都表现出家域收缩。全年都在使用草地和开阔林地栖息地类型，这与它们在领地内的可用性一致，而草地、开阔林地和茂密灌木丛是觅食的首选栖息地。我们基于纵向 GPS 数据的栖息地偏好结果，确定了理想的栖息地比例（草地：开阔林地：低灌丛为 1.00:6.10:0.09 公顷），以协助选择南方地犀鸟的合适再引入地点。随着越来越多的物种面临灭绝威胁，将它们重新引入合适的栖息地可能是一种有用的保护缓解措施。然而，我们的研究结果强调了在选择重新引入的区域之前，彻底了解物种的运动和空间利用的重要性，以确保这些物种在这些地点的建立和可持续性。
