foraging

觅食
  • 文章类型: Journal Article
    欧亚伐木鸡更喜欢其主要猎物的栖息地,蚯蚓,可以在更高的密度中找到。虽然它们是森林栖息的鸟类,他们经常在晚上参观牧场和天然草原,蚯蚓丰度普遍较高的地方。然而,关于栖息地特征和猎物可用性变化的精细尺度栖息地使用的信息很少,特别是在繁殖季节之后。在我们的研究中,我们调查了在迁徙中途停留期间,木鸡的夜间发生是否在两个相邻的田地之间有所不同,或管理单位,具有相似的植被结构,如果伐木鸡目击空间格局的场内变化与细尺度蚯蚓密度和土壤参数有关。具体来说,我们使用两个标记的木鸡的GPS跟踪数据和直接观测数据来研究繁殖前和繁殖后匈牙利混交林牧场景观中鸟类的发生模式。我们将这些模式与细尺度土壤特性和蚯蚓丰度进行了比较,通过现场采样获得。我们发现,蚯蚓丰度较高的田地,这种相关性在场内水平上也同样观察到。我们的结果表明,木鸡在多个空间尺度上选择了具有较高蚯蚓密度的觅食地点,两个字段之间(粗尺度),和领域内(精细尺度)。考虑到木鸡倾向于在晚上回到同一田地觅食,占用率和资源之间的紧密联系为在实地一级制定栖息地管理策略以进行保护提供了基础。由于蚯蚓密度和土壤参数是伐木公鸡觅食栖息地的良好指标,测量这些变量,至少在粗略的尺度上,可以帮助预测整个景观中物种的重要栖息地。
    The Eurasian woodcock prefers habitats where its main prey, earthworms, can be found in higher densities. Although they are forest-dwelling birds, they regularly visit pastures and natural grasslands at night, where earthworm abundance is generally higher. However, there is little information on fine-scale habitat use in relation to variation in habitat characteristics and prey availability, particularly beyond the breeding season. In our study, we investigated if the nocturnal occurrence of woodcocks during migratory stopover periods differed between two neighbouring fields, or management units, with similar vegetation structure, and if within-field variation in the spatial patterns of woodcock sightings were associated with fine-scale earthworm densities and soil parameters. Specifically, we used GPS tracking data of two tagged woodcocks and direct observation data to study patterns of occurrence of birds in a mixed forest-pasture landscape in Hungary during pre- and post-breeding periods. We compared these patterns with fine-scale soil characteristics and earthworm abundance, acquired by field sampling. We found that the field with higher earthworm abundance was visited by woodcocks more frequently, and this correlation was similarly observed at the intra-field level. Our results demonstrate that woodcocks select foraging sites with higher earthworm densities at multiple spatial scales, both between fields (coarse scale), and within fields (fine-scale). Considering that woodcocks tended to return to the same field to forage at night, the strong associations between occupancy and resources provide a basis for developing habitat management strategies at the field level for conservation. As earthworm densities and soil parameters are good indicators of woodcock foraging habitat, measuring those variables, at least at a coarse scale, could aid in predicting important habitats for the species across the landscape.
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  • 文章类型: Journal Article
    使用当地修复项目中通常播种的本地草和forb种子,我们进行了田间试验来评估种子物种的影响,种子斑块与巢的距离,和Owyhee收割蚂蚁去除种子模式上的斑块之间的距离,Pogonomyrmexsalinus(Olsen)(膜翅目:Formicidae)。要为蚂蚁种子首选项提供上下文,我们评估了种子物种之间处理时间的差异。此外,我们评估了cheatgrass的影响,Bromustectorum(L.)(酒类:禾本科),和桑德伯格蓝草,Poasecunda(J.Presl)(Poales:禾本科),覆盖种子去除。我们发现种子种类之间的去除率存在显着差异。总的来说,靠近巢穴的种子比远离巢穴的种子更容易被捕食,紧密间隔的斑块中的种子比宽间隔的斑块中的种子更脆弱。然而,这些影响的强度因种子种类而异。种子物种之间处理时间的差异可能有助于解释这些发现;对于需要较少的运输时间的物种,从巢距离的保护作用较弱。对于2种种子物种,种子斑块与巢的距离与斑块之间的距离之间存在相互作用,因此斑块之间的距离的保护作用随着与巢的距离的增加而减小。Cheatgrass和blugrass覆盖对种子的保护作用都很小。一起来看,这些结果提供了对收割蚂蚁觅食的空间生态学的见解,并可能为成功实施收割蚂蚁存在的恢复工作提供背景。
    Using a selection of native grass and forb seeds commonly seeded in local restoration projects, we conducted a field experiment to evaluate the effects of seed species, distance of seed patches from nests, and distance between patches on patterns of seed removal by Owyhee harvester ants, Pogonomyrmex salinus (Olsen) (Hymenoptera: Formicidae). To provide context for ants\' seed preferences, we evaluated differences in handling time among seed species. In addition, we assessed the influences of cheatgrass, Bromus tectorum (L.) (Poales: Poaceae), and Sandberg bluegrass, Poa secunda (J. Presl) (Poales: Poaceae), cover on seed removal. We found significant differences in removal rates among seed species. In general, seeds placed closer to nests were more vulnerable to predation than those placed farther away, and seeds in closely spaced patches were more vulnerable than seeds in widely spaced patches. However, the strength of these effects differed by seed species. Differences in handling time among seed species may help to explain these findings; the protective effect of from-nest distance was weaker for species that required less time to transport. For 2 of the seed species, there was an interaction between the distance of seed patches from nests and the distance between patches such that the protective effect of distance between patches decreased as the distance from nests increased. Cheatgrass and bluegrass cover both had small protective effects on seeds. Taken together, these results offer insight into the spatial ecology of harvester ant foraging and may provide context for the successful implementation of restoration efforts where harvester ants are present.
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  • 文章类型: Journal Article
    大黄蜂活动通常在降雨期间减少,使他们受到气候变化导致的降水频率增加的威胁。在飞行场所中使用了一种新型的雨机,以观察大黄蜂(Bombusterrestris)对殖民地和个体水平的模拟降雨的行为反应。降雨期间,离开竞技场的工人比例高于进入竞技场的工人比例,相反的是在干旱时期,这意味着当条件改善时,他们会补偿他们缺乏活动。在雨中休息的工人飞行和觅食的比例下降,而休息的比例增加。这种模式在干旱时期逆转,为补偿性活动提供进一步的证据。人们认为,下雨时休息行为的增加可以避免在潮湿时飞行的高昂能量成本,而不必不必要地返回巢穴。这种影响在个人时间预算中没有重复,用孤独的工人来衡量,这表明特定物种的存在加速了他们行为反应的决定,也许是通过局部增强。大黄蜂可能会利用社交线索来制定降水期间的能量支出策略,当条件改善时,它们可以补偿降雨期间觅食活动的减少。
    Bumblebee activity typically decreases during rainfall, putting them under the threat of the increased frequency of precipitation due to climate change. A novel rain machine was used within a flight arena to observe the behavioural responses of bumblebees (Bombus terrestris) to simulated rain at both a colony and individual level. During rainfall, a greater proportion of workers left the arena than entered, the opposite of which was seen during dry periods, implying that they compensate for their lack of activity when conditions improve. The proportion of workers flying and foraging decreased while resting increased in rain. This pattern reversed during dry periods, providing further evidence for compensatory activity. The increase in resting behaviour during rain is thought to evade the high energetic costs of flying while wet without unnecessarily returning to the nest. This effect was not repeated in individual time budgets, measured with lone workers, suggesting that the presence of conspecifics accelerates the decision of their behavioural response, perhaps via local enhancement. Bumblebees probably use social cues to strategize their energetic expenditure during precipitation, allowing them to compensate for the reduced foraging activity during rainfall when conditions improve.
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  • 文章类型: Journal Article
    许多动物的活动遵循反复的模式,觅食是其日常活动中最重要的过程之一。因此,确定寻找资源的运动以及理解觅食的时间和空间模式长期以来一直是行为生态学的中心。然而,识别和监测动物的运动往往是具有挑战性的。在这项研究中,我们评估了使用相机陷阱来跟踪非常特定和小规模的相互作用,该相互作用集中在Heliconiini蝴蝶的觅食行为上。使用三种以花粉为食的Heliconius物种的标记个体记录了花卉探视的数据(H。埃拉托,H.melpomene和H.sara),和两个密切相关,大型室外昆虫室中的非花粉摄食物种(Dryasiulia和Dryadulaphaetusa)。我们证明了相机陷阱可以多次和多次捕获单个花朵的访问,并使用我们的实验来描述其时空觅食模式的某些特征。Heliconiini蝴蝶在早晨表现出更高的活动,并具有很强的时间生态位重叠。观察到雄性和雌性之间觅食活动的差异,雌性觅食比雄性早,镜像已发表的实地研究。有些花比其他花更多,这可以解释为蝴蝶觅食同时影响彼此的花朵选择。喂食是在短时间内密集访问同一朵花,我们称之为喂食回合。Heliconius也经常访问同一朵花,与Helconius相比,非Helconius每天访问更多的花朵,并且它们的喂食次数更短。这与Heliconius比外群属具有更稳定的长期空间记忆和觅食偏好是一致的。更广泛地说,我们的研究表明,相机陷阱可以提供一个强大的工具来收集有关蝴蝶等小昆虫觅食行为的信息。©2024作者《生态学与进化》由JohnWiley&SonsLtd.出版。
    The activity of many animals follows recurrent patterns and foraging is one of the most important processes in their daily activity. Determining movement in the search for resources and understanding temporal and spatial patterns in foraging has therefore long been central in behavioural ecology. However, identifying and monitoring animal movements is often challenging. In this study we assess the use of camera traps to track a very specific and small-scale interactions focused on the foraging behaviour of Heliconiini butterflies. Data on floral visitation was recorded using marked individuals of three pollen-feeding species of Heliconius (H. erato, H. melpomene and H. sara), and two closely related, non-pollen feeding species (Dryas iulia and Dryadula phaetusa) in a large outdoor insectary. We demonstrate that camera traps efficiently capture individual flower visitation over multiple times and locations and use our experiments to describe some features of their spatial and temporal foraging patterns. Heliconiini butterflies showed higher activity in the morning with strong temporal niche overlap. Differences in foraging activity between males and females was observed with females foraging earlier than males, mirroring published field studies. Some flowers were more explored than others, which may be explained by butterflies foraging simultaneously affecting each other\'s flower choices. Feeding was grouped in short periods of intense visits to the same flower, which we refer to as feeding bouts. Heliconius also consistently visits the same flower, while non-Heliconius visited a greater number of flowers per day and their feeding bouts were shorter compared with Heliconius. This is consistent with Heliconius having more stable long-term spatial memory and foraging preferences than outgroup genera. More broadly, our study demonstrates that camera traps can provide a powerful tool to gather information about foraging behaviour in small insects such as butterflies. © 2024 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.
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  • 文章类型: Journal Article
    社会学习是许多物种用来有效获取有关其环境信息的机制。尽管许多动物生活在其他物种成员存在的环境中,关于种间社会学习知之甚少。驯化和城市化的物种提供了调查非人类动物是否可以从异类中学习的机会,例如人类,他们是社会景观的组成部分。尽管家犬犬已经被深入研究了它们向人类学习的能力,大多数研究都集中在像宠物一样生活的狗上。然而,自由放养的狗代表了世界上大多数狗的数量,它们和人类生活在一起,清除人类垃圾,并且受到自然和性选择的影响。因此,自由放养的狗广泛接触人类和他们的文物提供了机会,在自然主义的环境中研究种间社会学习,向人类学习可能对他们有好处。在这里,我们在受试者之间的设计中测试了单个自由放养的狗:对照组中的狗可以自发地在两个新颖且不同图案的食物递送盒之间进行选择。在实验组中,相反,狗可以首先观察到一个陌生的人接近并从2个盒子中的1个吃东西。我们提供了第一个证据,证明自由放养的狗与陌生人类的选择相匹配。这些结果表明,至少简单形式的种间社会学习可能参与狗在复杂的城市化环境中与人类一起生活的成功。
    Social learning is a mechanism used by many species to efficiently gain information about their environment. Although many animals live in an environment where members of other species are present, little is known about interspecific social learning. Domesticated and urbanized species provide the opportunity to investigate whether nonhuman animals can learn from heterospecifics such as humans, who are integral parts of their social landscape. Although domestic dogs Canis familiaris have been intensively researched for their ability to learn from humans, most studies have focused on dogs living as pets. However, free-ranging dogs represent the majority of the world\'s dog population, they live alongside humans, scavenge on human refuse, and are subject to natural and sexual selection. Thus, free-ranging dogs with extensive exposure to humans and their artifacts provide the opportunity to investigate interspecific social learning in a naturalistic setting, where learning from humans might be a benefit for them. Here we tested individual free-ranging dogs in a between-subject design: Dogs in the control group could spontaneously choose between two novel and differently patterned food-delivering boxes. In the experimental group, instead, dogs could first observe an unfamiliar human approaching and eating from 1 of the 2 boxes. We provide the first evidence that free-ranging dogs match the choice of an unfamiliar human. These results show that at least simple forms of interspecific social learning might be involved in dogs\' success in living alongside humans in a complex urbanized environment.
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  • 文章类型: Journal Article
    在全球鸟类中,水生鸟类以生活在暴露于大量光线的环境中而著称。尽管越来越多的证据表明,对光线的视觉适应是鸟类生命树的生态和进化的基础,对于全球水生动物,没有以眼睛大小近似的视敏度的全面比较分析。这里,我使用StanleyRitland的未发表的从博物馆标本中收集的轴向长度测量数据集,以探索一半水生动物(N=464种)的眼睛大小变化的生态学和演变。在校正体重异速测图并结合系统发育关系后,与陆地物种相比,水生物种的眼睛明显变小。此外,使用远视觅食策略的物种,展示食肉和食虫饮食,表现出夜间行为的眼睛更大。俯冲潜水员(如胸部和热带鸟类)和跟踪者(如苍鹭)的相对眼睛尺寸最大,特别是在较高海拔或较远距离识别猎物的物种。在更深处觅食的水下追捕潜水员的眼睛更大,可能是由于深海中光线的急剧衰减。总的来说,剩余的眼睛大小是系统发育保守的(l=0.94),仅系统发育就解释了62%的剩余眼睛大小变化。总的来说,这些结果表明,在水生生态系统中发现的相对明亮的环境否定了与发展和维持更大的眼睛相关的昂贵的代谢投资的适应性益处。同时也减少了残疾眩光的潜在发生。在不同的水生环境中,眼睛大小与觅食生态之间的强相关性证实了陆生鸟类的类似比较研究,并强调了视觉在推动全球鸟类的生态和进化中发挥的核心作用。
    Aquatic birds are notable among the global avifauna for living in environments exposed to large amounts of light. Despite growing evidence that visual adaptations to light underly the ecology and evolution of the avian tree of life, no comprehensive comparative analysis of visual acuity as approximated by eyes size exists for the global aquatic avifauna. Here, I use Stanley Ritland\'s unpublished dataset of measurements for axial length collected from museum specimens to explore the ecology and evolution of eye size variation for half of the aquatic avifauna (N = 464 species). After correcting for body mass allometry and incorporating phylogenetic relationships, aquatic species had significantly smaller eyes compared to terrestrial species. Furthermore, species using hyperopic foraging manoeuvres, exhibiting carnivorous and insectivorous diets, and displaying nocturnal behaviour had larger eyes. Plunge-divers (e.g. boobies and tropic birds) and stalkers (e.g. herons) had the largest relative eye sizes, especially species identifying prey at higher altitudes or longer distances. Underwater pursuit-divers foraging at greater depths had larger eyes, likely due to the dramatic attenuation of light in the deep ocean. Overall, residual eye size was phylogenetically conserved (l = 0.94), with phylogeny alone explaining 62% of residual eye size variation. Collectively, these results suggest that the relatively bright environments found in aquatic ecosystems negate the adaptive benefits of costly metabolic investments associated with developing and maintaining larger eyes, while also reducing the potential occurrence of disability glare. Strong correlations between eye size and foraging ecology in different aquatic environments corroborate similar comparative studies of terrestrial birds and underscore the central role that vision has played in driving the ecology and evolution of the global avifauna.
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  • 文章类型: Journal Article
    最佳觅食理论认为,动物的目标是最大程度地吸收能量,同时最大程度地减少觅食过程中的捕食和处理成本。大多数观察到的动物行为都支持这一理论,但是偶尔的偏差提供了对影响觅食决策的生态因素的见解。我们使用tokay壁虎中不同猎物大小之间的两选测试来测试猎物大小偏好。我们希望壁虎更喜欢更大的猎物,而当歧视更加困难并且提供小型猎物时,决策延迟会更长。当大小差异较大时,壁虎更喜欢较大的猎物,尽管决策延迟保持一致。这与先前关于坐着等待捕食者的研究是一致的。加上先前的发现,显示了在Tokay壁虎中捕获猎物后的冻结行为,我们的发现表明,避免捕食者对觅食决策的强烈影响,为将来研究tokay壁虎中决策与避免捕食者之间的联系开辟了一条新途径。
    The optimal foraging theory posits that animals aim to maximize energy intake while minimizing predation and handling costs during foraging. Most observed animal behaviour supports this theory, but occasional deviations provide insights into the ecological factors that shape foraging decisions. We tested prey-size preference using a two-choice test between different prey sizes in tokay geckos. We expected geckos to prefer larger prey and decision latencies to be longer when discrimination was more difficult and when small prey was offered. Geckos preferred larger prey when the size difference was large, although decision latency remained consistent. This aligns with prior research on sit-and-wait predators. Together with previous findings showing freezing behaviour after prey capture in tokay geckos, our findings suggest a strong influence of predator avoidance on foraging decisions opening up a new avenue for future research investigating the link between decision making and predator avoidance in tokay geckos.
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  • 文章类型: Journal Article
    动物区系保护越来越依赖于没有侵入性捕食者的保护区,虽然有种群会失去抗捕食者的特征,可能使它们不太适合“超越栅栏”的生活。在避风港内维持低水平的哺乳动物捕食者压力可能会阻止种群中的抗捕食者性状的丧失。我们机会主义地比较了四个woylie(Bettongiapenicillataogilbyi)种群之间的行为和形态上的反捕食者特征-一个从所有哺乳动物捕食者中分离出来的避风港,一个含有天然哺乳动物捕食者的避风港(chuditch;Dasyurusgeoffroii),以及它们各自的非同源对应物(每个都包含chuditch和侵入性捕食者)。没有哺乳动物掠食者的情况下存在的被庇护的woylies较小(后脚较短,较小的体重)和较低的反应性(从狐狸处理和控制喂养站消耗更多的食物,在人类处理期间不那么激动)比非参考人群。然而,在包含chuditch的避风港,我们发现,与邻近的非人口相比,在行为或形态上没有差异。在人群中,在捕食者活动较高的地点,反捕食者反应倾向于显得更强,暗示在捕食压力梯度上的适应性反应。我们的发现表明,在保护区中保持哺乳动物的捕食压力可以有效地防止或减缓这些种群中抗捕食者性状的丧失。
    Conservation havens free of invasive predators are increasingly relied upon for fauna conservation, although havened populations can lose anti-predator traits, likely making them less suitable for life \'beyond the fence\'. Sustaining low levels of mammalian predator pressure inside havens may prevent the loss of anti-predator traits from havened populations. We opportunistically compared behavioural and morphological anti-predator traits between four woylie (Bettongia penicillata ogilbyi) populations- one haven isolated from all mammalian predators, one haven containing a native mammalian predator (chuditch; Dasyurus geoffroii), and their respective non-havened counterparts (each containing both chuditch and invasive predators). Havened woylies existing without mammalian predators were smaller (shorter hindfeet, smaller body weight) and less reactive (consumed more food from fox-treated and control feeding stations, less agitated during human handling) than a non-havened reference population. However, in the haven containing chuditch, we found no difference in behaviour or morphology compared to the adjacent non-havened population. Across populations, anti-predator responses tended to appear stronger at sites with higher predator activity, suggestive of an adaptive response across a gradient of predation pressure. Our findings suggest that maintaining mammalian predation pressure in conservation havens could be effective for preventing or slowing the loss of anti-predator traits from these populations.
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  • 文章类型: Journal Article
    虽然各种海洋捕食者形成协会,最常见的研究是地下捕食者和海鸟之间的研究,海鸥,剪毛水或燕鸥经常与海豚共存,比目鱼或金枪鱼。然而,这些关联的潜在机制仍然知之甚少.已经提出了三个假设来解释这些关联的普遍性:(1)地下捕食者将猎物聚集到地面,并使鸟类可以接近猎物,(2)地下捕食者伤害靠近地面的猎物,从而向鸟类提供食物残渣,(3)水下捕食者的攻击降低了猎物群的凝聚力,从而降低了它们的集体防御能力,使猎物更容易被鸟类捕获。使用无人机镜头,我们调查了印度太平洋旗鱼(Istiophorusplatypterus)和燕鸥(Onychoprionsp。)在马来西亚半岛东海岸捕食养鱼。通过对两种掠食性物种的狩猎行为的时空分析和猎物凝聚力的直接测量,我们表明当学校凝聚力低时,燕鸥会受到攻击,这种凝聚力的下降经常是由旗鱼袭击引起的。因此,我们建议旗鱼为鸟类创造副产品利益,支持降低凝聚力可以促进地下捕食者和海鸟之间的联系的假设。
    While various marine predators form associations, the most commonly studied are those between subsurface predators and seabirds, with gulls, shearwaters or terns frequently co-occurring with dolphins, billfish or tuna. However, the mechanisms underlying these associations remain poorly understood. Three hypotheses have been proposed to explain the prevalence of these associations: (1) subsurface predators herd prey to the surface and make prey accessible to birds, (2) subsurface predators damage prey close to the surface and thereby provide food scraps to birds, and (3) attacks of underwater predators lower the cohesion of prey groups and thereby their collective defences making the prey easier to be captured by birds. Using drone footage, we investigated the interaction between Indo-Pacific sailfish (Istiophorus platypterus) and terns (Onychoprion sp.) preying on schooling fish off the eastern coast of the Malaysian peninsula. Through spatio-temporal analysis of the hunting behaviour of the two predatory species and direct measures of prey cohesion we showed that terns attacked when school cohesion was low, and that this decrease in cohesion was frequently caused by sailfish attacks. Therefore, we propose that sailfish created a by-product benefit for the bird species, lending support to the hypothesis that lowering cohesion can facilitate associations between subsurface predators and seabirds.
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  • 文章类型: Journal Article
    动物觅食从根本上取决于食物的分配和供应。然而,时空食物分布的量化很少,但对于解释物种间觅食行为的变化至关重要,人口,或个人。聚集但短暂的食物来源可以快速摄入能量,但需要加大努力才能找到,3可以产生可变的觅食成功,4,迫使动物更有效地觅食。我们量化了此类资源可用性的季节性变化,以测试食物分配对运动模式变化的直接影响。新热带小型斗牛犬蝙蝠(Noctilioalbiventris)在季节性环境中对新兴的水生昆虫觅食,其数量在黄昏后不久达到峰值。5,6我们使用GPS跟踪蝙蝠,并在雨季和旱季使用浮动相机陷阱量化其觅食区域中的夜间昆虫分布。令人惊讶的是,在雨季,昆虫的数量减少了75%,成群的寿命缩短了60%(短暂)。因此,雨季蝙蝠每晚必须飞行两倍远(距离的总距离和最大距离)和45%更长(持续时间)。在觅食的回合中,湿季蝙蝠在每个昆虫斑块上花费的时间更少,寻找后续斑块的时间更长,反映了昆虫的时间短暂性增加和空间可预测性降低。我们的结果强调了觅食努力与食物的时空分布之间的紧密联系,以及繁殖对行为灵活性和对移动猎物的高度动态资源景观的适应施加的约束的影响。7,8根据资源的时空动态检查觅食行为可以帮助预测动物如何应对环境变化引起的食物可获得性变化。
    Animal foraging is fundamentally shaped by food distribution and availability.1 However, the quantification of spatiotemporal food distribution is rare2 but crucial to explain variation in foraging behavior among species, populations, or individuals. Clumped but ephemeral food sources enable rapid energy intake but require increased effort to find,3 can generate variable foraging success,4 and force animals to forage more efficiently. We quantified seasonal shifts in the availability of such resources to test the proximate effects of food distribution on changes in movement patterns. The neotropical lesser bulldog bat (Noctilio albiventris) forages in a seasonal environment on emerging aquatic insects, whose numbers peak shortly after dusk.5,6 We GPS-tracked bats and quantified nocturnal insect distribution in their foraging area using floating camera traps across wet and dry seasons. Surprisingly, insects were 75% less abundant and swarms were 60% shorter lived (more ephemeral) in the wet season. As a result, wet season bats had to fly twice as far (total and maximum distance fromroost distances) and 45% longer (duration) per night. Within foraging bouts, wet season bats spent less time in each insect patch and searched longer for subsequent patches, reflecting increased temporal ephemerality and decreased spatial predictability of insects. Our results highlight the tight link between foraging effort and spatiotemporal distribution of food and the influence of constraints imposed by reproduction on behavioral flexibility and adaptations to the highly dynamic resource landscapes of mobile prey.7,8 Examining foraging behavior in light of spatiotemporal dynamics of resources can help predict how animals respond to shifts in food availability caused by escalating environmental changes.
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