In-water observations highlight the effects of provisioning on whale shark behaviour at the world’s largest whale shark tourism destination

The whale shark is the world’s largest fish that forms predictable aggregations globally, many of which support tourism industries. The largest non-captive provisioned whale shark destination globally is at Oslob, Philippines, where >500,000 tourists visit yearly. There, the sharks are provisioned daily, year-round, allowing the human-shark interaction in nearshore waters. We used in-water behavioural observations of whale sharks between 2015 and 2017 to understand the relationship between external stimuli and shark behaviour, whether frequency of visits at the site can act as a predictor of behaviour, and the tourist compliance to the code of conduct. Mixed effects models revealed that the number of previous visits at the site was a strong predictor of whale shark behaviour, and that provisioned sharks were less likely to exhibit avoidance. Compliance was poor, with 93% of surveys having people <2 m from the animal, highlighting overcrowding on whale sharks at Oslob. Given the behavioural implications to whale sharks highlighted here and the local community’s reliance on the tourism industry, it is imperative to look into improving management strategies to increase tourist compliance and strive for sustainable tourism practices.
Methods
The dataset was collected using through dedicated focal follows (Altmann, 1974) between February 2015 and May 2017. Within each survey, an assigned researcher would follow the first shark randomly encountered within the study area and identify the individual using photo-identification. The researcher would gather observations of the shark's predominant behaviour, and as well as events and the individual's corresponding reactions. Tourist compliance to the local code of conduct was also recorded within each survey.

The data gathered was processed by fitting a binomial generalised linear mixed model (GLMM) using the R program to determine variables that influence whale shark behaviour.

鲸鲨（whale shark）是全球体型最大的鱼类，在全球范围内会形成可预测的聚集群，其中多数聚集区支撑了当地旅游业发展。全球规模最大的野生人工投喂鲸鲨观赏目的地位于菲律宾奥斯洛布（Oslob），该站点每年接待游客超50万人次。当地全年每日均会投喂鲸鲨，使得游客可在近岸水域与鲸鲨开展互动。本研究于2015至2017年间开展鲸鲨水下行为观测，旨在探究外部刺激与鲸鲨行为之间的关联、该观测点的到访频次能否作为鲸鲨行为的预测因子，以及游客对当地行为准则的遵守情况。混合效应模型结果显示，过往到访该观测点的次数是鲸鲨行为的强预测因子，且人工投喂的鲸鲨更不易表现出躲避行为。游客合规情况欠佳，93%的观测记录显示有游客距离鲸鲨不足2米，凸显了奥斯洛布鲸鲨观赏区域的过度拥挤问题。鉴于本研究揭示的鲸鲨行为影响，以及当地社区对旅游业的高度依赖，亟需优化管理策略以提升游客合规性，并推行可持续旅游实践。

研究方法
本数据集采集自2015年2月至2017年5月间的标准化目标个体跟踪法（focal follows，Altmann, 1974）。每次调查中，指派的研究人员会随机选取研究区域内首次遇见的鲸鲨作为跟踪对象，并通过照片识别法确认个体身份。研究人员会记录鲸鲨的主要行为、各类事件及其对应的个体反应，同时在每次调查中记录游客对当地行为准则的遵守情况。

所采集的数据通过R语言程序拟合二项式广义线性混合模型（GLMM），以筛选影响鲸鲨行为的相关变量。