Speakman Cassie N, Lloyd Sebastian T, Camprasse Elodie C M, Hoskins Andrew J, Hindell Mark A, Costa Daniel P, Arnould John P Y
School of Life and Environmental Sciences Deakin University Burwood Vic. Australia.
CSIRO Health and Biosecurity Townsville Qld Australia.
Ecol Evol. 2021 Mar 13;11(9):4428-4441. doi: 10.1002/ece3.7337. eCollection 2021 May.
Substantial variation in foraging strategies can exist within populations, even those typically regarded as generalists. Specializations arise from the consistent exploitation of a narrow behavioral, spatial or dietary niche over time, which may reduce intraspecific competition and influence adaptability to environmental change. However, few studies have investigated whether behavioral consistency confers benefits at the individual and/or population level. While still recovering from commercial sealing overexploitation, Australian fur seals (AUFS; ) represent the largest marine predator biomass in south-eastern Australia. During lactation, female AUFS adopt a central-place foraging strategy and are, thus, vulnerable to changes in prey availability. The present study investigated the population-level repeatability and individual consistency in foraging behavior of 34 lactating female AUFS at a south-east Australian breeding colony between 2006 and 2019. Additionally, the influence of individual-level behavioral consistency on indices of foraging success and efficiency during benthic diving was determined. Low to moderate population-level repeatability was observed across foraging behaviors, with the greatest repeatability in the mean bearing and modal dive depth. Individual-level consistency was greatest for the proportion of benthic diving, total distance travelled, and trip duration. Indices of benthic foraging success and efficiency were positively influenced by consistency in the proportion of benthic diving, trip duration and dive rate but not influenced by consistency in bearing to most distal point, dive depth or foraging site fidelity. The results of the present study provide evidence of the benefits of consistency for individuals, which may have flow-on effects at the population level.
即使在通常被视为泛化种的种群中，觅食策略也可能存在很大差异。随着时间的推移，专业化源于对狭窄行为、空间或饮食生态位的持续利用，这可能会减少种内竞争并影响对环境变化的适应性。然而，很少有研究调查行为一致性是否在个体和/或种群水平上带来益处。澳大利亚海狗（AUFS）在从商业捕杀的过度开发中恢复的过程中，是澳大利亚东南部最大的海洋捕食者生物量。在哺乳期，雌性澳大利亚海狗采用中心地觅食策略，因此容易受到猎物可获得性变化的影响。本研究调查了2006年至2019年间在澳大利亚东南部一个繁殖地的34只哺乳期雌性澳大利亚海狗觅食行为的种群水平重复性和个体一致性。此外，还确定了个体水平行为一致性对底栖潜水期间觅食成功率和效率指标的影响。在觅食行为中观察到低到中等的种群水平重复性，平均方位和模式潜水深度的重复性最大。底栖潜水比例、总行进距离和行程持续时间的个体水平一致性最大。底栖觅食成功率和效率指标受到底栖潜水比例、行程持续时间和潜水率一致性的积极影响，但不受最远点方位、潜水深度或觅食地点保真度一致性的影响。本研究结果提供了一致性对个体有益的证据，这可能在种群水平上产生连锁反应。
