Bhanda Geetika, Oleksy Ryszard Z, Reinegger Raphaël D, Baider Cláudia, Florens F B Vincent
Tropical Island Biodiversity, Ecology and Conservation Pole of Research, Faculty of Science, University of Mauritius, Le Réduit, Mauritius.
Ecosystem Restoration Alliance Indian Ocean, St. Pierre, Mauritius.
PeerJ. 2025 Apr 21;13:e19269. doi: 10.7717/peerj.19269. eCollection 2025.
Human-wildlife conflicts pose a growing threat to biodiversity, particularly when the targeted species plays an ecological keystone role. Mauritius has repeatedly mass-culled an endemic and threatened flying fox species (the Mauritian flying fox; ) failing the intended objectives of crop protection and elevating the species' extinction risks. In this context, the ecology of this species should be better understood to develop non-lethal management strategies. Here we investigated foraging patterns of vertebrate frugivores over 24 hour cycles in lychee orchards and backyard gardens. We assessed all agents of damage (mainly flying fox, alien bird, alien mammal) and the temporal variation of flying fox and bird foraging (take and amount eaten relative to fruit ripeness) on lychee trees. The most important frugivores foraging on lychees were flying foxes (78.3%) and birds (16.1%), namely ring-necked parakeets (), red-whiskered bulbuls (), village weavers () and common mynas () while damage by alien mammals was negligible (<1%). Flying foxes consumed more fruits in the early night (59%) compared to the late night and this was statistically significant in one orchard and backyards. However, the difference in damage was on average one to three fruits per tree per night. Bird damage at both orchards was highest during the first half of the day (64%). Flying foxes ate fewer fruits towards the end of the fruiting season while birds followed the opposite trend. As fruit ripeness increased from unripe to fully ripe, flying foxes ate 39-42% more lychee pulp per fruit at the two orchards. Parakeets ate 7% more fruit pulp with increasing ripeness at one orchard only. Deliberate disturbances involving smoke, noise or light to deter flying foxes were common in orchards. The weak difference in the extent of flying fox damage to fruits between early and late night suggested at best minor advantages of concentrating deliberate disturbances in early night, and that netting would be a better strategy as it would also protect against diurnal frugivores. Additionally, trees should be protected from the sixth week after fruit set as most damage occurred when fruits were unripe. Such an improved timing of crop protection should play an important role in reducing fruit losses and thereby alleviate the human-wildlife conflict around the flying fox's diet.
人类与野生动物的冲突对生物多样性构成了日益严重的威胁，尤其是当目标物种发挥生态关键作用时。毛里求斯多次大规模捕杀一种地方性濒危狐蝠物种（毛里求斯狐蝠），未能实现保护作物的预期目标，反而增加了该物种的灭绝风险。在这种情况下，应该更好地了解该物种的生态，以制定非致命的管理策略。在此，我们调查了荔枝果园和后院花园中脊椎动物食果动物在24小时周期内的觅食模式。我们评估了所有造成损害的因素（主要是狐蝠、外来鸟类、外来哺乳动物）以及狐蝠和鸟类在荔枝树上觅食的时间变化（取食情况以及相对于果实成熟度的食量）。在荔枝上觅食的最重要的食果动物是狐蝠（78.3%）和鸟类（16.1%），即环颈鹦鹉、红耳鹎、织巢鸟和家八哥，而外来哺乳动物造成的损害可以忽略不计（<1%）。与深夜相比，狐蝠在傍晚消耗的果实更多（59%），在一个果园和后院中这具有统计学意义。然而，平均每晚每棵树的损害差异为一到三个果实。两个果园中鸟类造成的损害在白天的前半段最高（64%）。在结果季节末期，狐蝠吃的果实较少，而鸟类则呈现相反的趋势。随着果实成熟度从不成熟增加到完全成熟，在两个果园中，狐蝠每个果实食用的荔枝果肉增加了39 - 42%。仅在一个果园中随着成熟度增加，鹦鹉食用的果肉增加了7%。果园中常见使用烟雾、噪音或灯光等蓄意干扰来驱赶狐蝠。傍晚和深夜狐蝠对果实造成损害的程度差异不大，这表明将蓄意干扰集中在傍晚最多只有些许优势，而设置网罩是更好的策略因为它还能防止白天食果动物的侵害。此外，从坐果后第六周起就应该保护树木，因为大多数损害发生在果实未成熟时。这种改进的作物保护时机对于减少果实损失从而缓解围绕狐蝠食物的人类与野生动物冲突应能发挥重要作用。
