Carter Neil H, Zuckerwise Amelia, Pradhan Narendra Man Babu, Subedi Naresh, Lamichhane Babu Ram, Hengaju Krishna Dev, Acharya Hari Bhadra, Kandel Ram Chandra
School for Environment and Sustainability, University of Michigan, Ann Arbor, MI, USA.
International Union for Conservation of Nature, Lalitpur, Kathmandu, Nepal.
Glob Ecol Conserv. 2023 Apr;42:e02388. doi: 10.1016/j.gecco.2023.e02388. Epub 2023 Jan 23.
Roads pose a major, and growing, challenge for the conservation of endangered species. However, very little is known about how endangered species behaviorally respond to roads and what that means for road mitigation strategies. We used the nation-wide lockdown in Nepal during the COVID-19 pandemic as a natural experiment to investigate how dramatic reductions in traffic volume along the national highway affected movements of two GPS-collared tigers ()-a globally endangered species. This work is the first systematic research on tigers in Nepal using radiotelemetry or GPS tracking data since the 1980s. We found that the highway more strongly constrained the space use and habitat selection of the male in Parsa National Park than the female in Bardia National Park. Over the entire study period, the female on average crossed 10 times more often per week than the male, and when he was near the highway, he was over 11 times more probable to not cross it than to cross during the day. However, we also found that the cessation of traffic during the pandemic lockdown relaxed tiger avoidance of roads and made the highway more permeable for both animals. They were 2-3 times more probable to cross the highway during the lockdown than before the lockdown. In the month following the lockdown, the space use area of the male tiger tripled in size (160-550 km), whereas the female's shrunk to half its previous size (33-15 km). These divergent patterns likely reflect differences between the two parks in their highway traffic volumes and regulations as well as ecological conditions. Our results provide clear evidence that vehicle traffic on major roads impede tiger movements, but also that tigers can respond quickly to reductions in human pressures. We conclude by identifying various actions to mitigate road impacts on tigers and other endangered species.
道路对濒危物种的保护构成了重大且日益严峻的挑战。然而，对于濒危物种如何在行为上对道路做出反应以及这对道路缓解策略意味着什么，我们知之甚少。我们利用新冠疫情期间尼泊尔全国范围的封锁作为一项自然实验，来研究国家高速公路上车流量的大幅减少如何影响两只佩戴GPS项圈的老虎（一种全球濒危物种）的活动。这项工作是自20世纪80年代以来首次利用无线电遥测或GPS跟踪数据对尼泊尔老虎进行的系统研究。我们发现，与巴迪亚国家公园的雌性老虎相比，高速公路对帕尔萨国家公园雄性老虎的空间利用和栖息地选择的限制更强。在整个研究期间，雌性老虎平均每周穿越的次数比雄性老虎多10倍，而且当雄性老虎靠近高速公路时，它在白天不穿越高速公路的可能性比穿越的可能性高出11倍多。然而，我们还发现，疫情封锁期间交通的停止缓解了老虎对道路的回避，使高速公路对两只老虎来说都变得更具通透性。它们在封锁期间穿越高速公路的可能性比封锁前高出2至3倍。在封锁后的一个月里，雄性老虎的空间利用面积增加了两倍（从160平方公里增至550平方公里），而雌性老虎的空间利用面积缩小到之前大小的一半（从33平方公里减至15平方公里）。这些不同的模式可能反映了两个公园在高速公路交通流量、规定以及生态条件方面的差异。我们的结果提供了明确的证据，表明主要道路上的车辆交通阻碍了老虎的活动，但同时也表明老虎能够对人类压力的减少迅速做出反应。我们最后确定了各种减轻道路对老虎和其他濒危物种影响的行动。
