Implications of survey effort on estimating demographic parameters of a long-lived marine top predator

Effective management of wildlife populations rely on knowledge of their abundance, survival and reproductive rates. Maintaining long-term studies capable of estimating demographic parameters for long-lived, slow reproducing species is challenging. Insights into effects of research intensity on the statistical power to estimate demographic parameters is limited. Here, we investigate implications of survey effort on estimating abundance, home range sizes and reproductive output of Indo-Pacific bottlenose dolphins (Tursiops aduncus), using a three-year sub-sample of a long-term, capture-recapture study off Bunbury, Western Australia. Photo-identification on individual dolphins were collected following Pollock’s Robust Design, where seasons were defined as ‘primary periods’, each consisting of multiple ‘secondary periods’. The full dataset consisted of 12 primary periods and 72 secondary periods, resulting in the study area being surveyed 24 times/year. We simulated reduced survey effort by...

野生动物种群的有效管理，有赖于对其种群丰度、存活率与繁殖率的认知。针对寿命长、繁殖缓慢的物种，开展可估算其种群统计参数的长期研究颇具挑战。目前学界关于研究强度对种群统计参数估算统计效力影响的认知仍较为有限。本研究依托澳大利亚西部邦伯里海域一项长期标记重捕（capture-recapture）研究的三年子样本，探究调查强度对印太瓶鼻海豚（Indo-Pacific bottlenose dolphins, Tursiops aduncus）种群丰度、家域面积与繁殖产出估算的影响。本研究采用波洛克稳健设计（Pollock’s Robust Design）采集海豚个体照片识别数据：将季候定义为‘主周期’，每个主周期包含多个‘次周期’。完整数据集包含12个主周期与72个次周期，使得研究区域每年的调查次数达24次。我们通过……模拟了降低后的调查强度。