Gálvez Dumas, Romero Emilio, Murcia-Moreno Daniel, Bonilla Braulio, Valdés Roderick
Coiba Scientific Station, City of Knowledge, Calle Gustavo Lara, Bld. 145B, Clayton, 0843-01853, Panama.
Programa Centroamericano de Maestría en Entomología, Universidad de Panamá, Ciudad de Panamá, Estafeta universitaria, Avenida Simón Bolívar, 0824, Panama.
Heliyon. 2024 Oct 30;10(21):e39986. doi: 10.1016/j.heliyon.2024.e39986. eCollection 2024 Nov 15.
Animals' fitness is determined in a large proportion by the balance in energetic requirements maintained during daily activities, in response to environmental factors. Predation is a major environmental factor influencing the activity patterns of prey, and the deployment of adaptive responses to predation represents a significant cost to prey populations and communities. Experimental removal of predators to study the effect on activity patterns of prey is impractical for vertebrate species. However, islands are often deprived of predators and provide an excellent arena to study prey's responses in the absence of any cue related to predation risk. Here, we investigated whether natural absence of predators in islands has influenced the activity patterns of diurnal agoutis in Panama, by monitoring activity in three sites in each habitat type (predator-free vs predator). We predicted that agoutis in predator-free sites can expand their activity patterns towards the night, which is the period of highest predation risk, in sites with predators. One of our predator-free sites showed relative high activity at night, with no evidence of nocturnality in sites with predators. A clear pattern across our three predator-free sites was that agoutis started their daily activity earlier, before sunrise, which is a period with significant predation risk as well. Our study highlights the role that felids play in regulating agoutis' daily activity patterns and we discuss the implications of our finding. Finally, we also offer a review on agoutis' activity pattern in the Neotropics.
动物的适应性在很大程度上取决于日常活动中为响应环境因素而维持的能量需求平衡。捕食是影响猎物活动模式的一个主要环境因素，而对捕食采取适应性反应的行为对猎物种群和群落来说是一项巨大的成本。通过实验移除捕食者来研究其对猎物活动模式的影响，对于脊椎动物物种来说是不切实际的。然而，岛屿通常没有捕食者，为研究猎物在没有任何与捕食风险相关线索情况下的反应提供了一个绝佳的场所。在此，我们通过监测每种栖息地类型（无捕食者与有捕食者）的三个地点的活动情况，调查了巴拿马岛屿上自然缺乏捕食者是否影响了昼行性刺豚鼠的活动模式。我们预测，在无捕食者的地点，刺豚鼠的活动模式可以向夜间扩展，而在有捕食者的地点，夜间是捕食风险最高的时段。我们的一个无捕食者地点在夜间表现出相对较高的活动，而在有捕食者的地点没有夜行性的迹象。在我们的三个无捕食者地点呈现出一个明显的模式，即刺豚鼠在日出前更早开始它们的日常活动，而这也是一个捕食风险显著的时段。我们的研究突出了猫科动物在调节刺豚鼠日常活动模式中所起的作用，并且我们讨论了我们这一发现的意义。最后，我们还对新热带地区刺豚鼠的活动模式进行了综述。
