Kelm Detlev H, Langheld Manuel, Nogueras Jesús, Popa-Lisseanu Ana G, Ibáñez Carlos
Estación Biológica de Doñana (CSIC), Seville, Spain.
R Soc Open Sci. 2023 Aug 16;10(8):230309. doi: 10.1098/rsos.230309. eCollection 2023 Aug.
Owls prey on bats, but information on owl predation is scarce, its impact on bat mortality is unclear, and reports on behavioural responses, including roost-switching and fission-fusion behaviour, are equivocal. To study the link between owl predation and anti-predator behaviour in bats, we evaluated seven months of video recordings at roosts and the behaviour of 51 passive integrated transponder (PIT)-tagged bats and bats without tags in a geographically isolated colony of greater noctule bats () in Spain. We found the tawny owl to almost continuously hunt , from perches and on the wing, well after the bats emerged at dusk and when they returned to their roosts. We recorded 39 unsuccessful and three successful attacks. Nonetheless, we found no evidence that owl predation modifies bat behaviour. While the bats constituted only a very small proportion of the owls' diet, owl predation accounted for an estimated 30-40% of bat mortality, which may have a significant impact on small, local or isolated bat populations, in particular, and thereby shape regional bat distributions. We hypothesize that low roost availability may also affect the bats' potential response to predation, which could lead to natural predation having an excessive impact on bat populations.
猫头鹰捕食蝙蝠，但关于猫头鹰捕食的信息很少，其对蝙蝠死亡率的影响尚不清楚，关于包括换栖和裂变融合行为在内的行为反应的报道也模棱两可。为了研究猫头鹰捕食与蝙蝠反捕食行为之间的联系，我们评估了西班牙一个地理隔离的大棕蝠（）群体中七个月的栖息地视频记录，以及51只带有被动集成应答器（PIT）标签的蝙蝠和未带标签的蝙蝠的行为。我们发现，在蝙蝠黄昏出现后以及返回栖息地时，茶色雕鸮几乎会持续从栖息处和飞行中捕食。我们记录了39次未成功和3次成功的攻击。尽管如此，我们没有发现证据表明猫头鹰捕食会改变蝙蝠的行为。虽然蝙蝠在猫头鹰的食物中只占很小的比例，但猫头鹰捕食估计占蝙蝠死亡率的30%-40%，这可能尤其会对小型、局部或隔离的蝙蝠种群产生重大影响，从而影响区域蝙蝠分布。我们推测，低栖息可用性也可能影响蝙蝠对捕食的潜在反应，这可能导致自然捕食对蝙蝠种群产生过度影响。
