Dolphin Watching and Compliance to Guidelines Affect Spinner Dolphins’ (Stenella longirostris) Behaviour in Reunion Island

Marine wildlife tourism has rapidly developed in Reunion Island, due to a large demand for interactions with a resident population of spinner dolphins (Stenella longirostris). The presence of dolphin-watching vessels close to dolphin groups can cause short-term impacts on their behaviour; cumulative incidences likely result in deleterious long-term impacts on the population. Using scan sampling, we collected behavioural data on spinner dolphins to evaluate the short-term effects of dolphin watching on their behaviour. The dolphins were less likely to begin socialising or diving while travelling and more likely to stay travelling and milling in the presence of vessels. Additionally, activity budgets for resting and socialising decreased simultaneously with increased travelling and milling. Avoidance responses significantly increased with an increase in the number of vessels and non-compliance with the local dolphin-watching guidelines. These behavioural responses are likely to have energetic costs for the dolphins, which may lead to decreased survival and reproductive success at individual and population levels. More restrictive regulations, increased surveillance and animal-based measures are key tools to adapt the conservation efforts in Reunion Island. Further studies on the island’s resident dolphin populations are necessary to ensure the continuity of dolphin-watching activities in a sustainable manner.

How empathy-based sensitisation and knowledge reinforcement affect policy compliance: a case study of dolphin watching, Ecuador

Cetacean watching is an increasingly popular economic activity in Ecuador for tourism operators. Despite government regulations, cetacean watching can have a negative impact on observed animal populations. To enhance good dolphin-watching practices, a course was carried out in Puerto El Morro, Ecuador about sensitisation activities promoting empathy towards and knowledge about bottlenose dolphins, local avifauna and mangrove ecosystems. The course provided tourism operator staff with theoretical and practical knowledge on dolphin physiology and ecology, with a focus on empathy towards the species and on regulations to be respected during the watching tours. The course included interactive workshops, didactic materials, advice, video screening and structured conversations. Two innovative questionnaires were implemented on the boat during 68 dolphin-watching tours to evaluate whether the training course had improved the regulation compliance and on-tour guiding quality of the tour guides and boat drivers. The results showed a statistically significant improvement in dolphin-watching practices in compliance with the “Regulations for the Whale and Dolphin Watching of Ecuador” (p = .0002) and in guidance quality (p = .0004) after the training course. Boat drivers were identified as influential actors in compliance with regulations and should also be included in the environmental awareness training courses. The study showed that empathy-based sensitisation and knowledge reinforcement positively affect policy compliance and can generate new sustainable approaches for future dolphin-watching activities.

Nautical tourism affects common bottlenose dolphin (Tursiops truncatus M.) foraging success in a NATURA 2000 site, North-Eastern Adriatic Sea

Several studies indicate that unregulated nautical tourism can have negative implications on cetacean behaviour. In recent years, dolphin watching activities (DWA) have increased off the West coast of Istria, Croatia, a region in which the NATURA 2000 site: ‘Akvatorij zapadne Istre’ has been proposed to be designated for bottlenose dolphins (Tursiops truncatus M.). For data collected between 2016 and 2019, we compared dolphin group behaviours from this region during impact (presence of nautical tourism boats (NTBs)) and control (absence of NTBs) scenarios, as well as providing descriptive analysis on the displacement of individuals in the presence of NTBs. Throughout the study years, 48.5 % of NTBs were observed within 15m of the dolphin focal groups and 97 % were observed within 50 m distance. The greatest rates of displacement in dolphin focal groups occurred when NTB numbers were greatest per individual dolphin. Markov chain analysis were used to quantify the short-term effects of NTB presence on dolphin behaviour. In the presence of NTBs, dolphins were more likely to spend time milling and less time foraging. Cumulative behavioural budgets, derived by accounting for the time bottlenose dolphins spent in the presence or absence of NTBs, indicated that vessel exposure levels of 14 % and 25 % were enough to statistically affect milling and foraging behaviours respectively. To lessen the lack of sustainable DWA, the implementation of relevant guidelines, e.g. Global Best Practice Guidance for Responsible Whale and Dolphin Watching (50 m no approach and 300 m caution zone) is therefore crucial to mitigate any long-term consequences the actions of NTBs may have on this key species. To date, 162 bottlenose dolphins have been photo-identified off West coast of Istria and cumulative interference to this population could affect direct ecosystem functioning.

Dolphin-Watching Boats Affect Whistle Frequency Modulation in Bottlenose Dolphins

Bottlenose dolphins’ whistles are key in social communication, conveying information about conspecifics and the environment. Therefore, their study can help to infer habitat use and identify areas of concern due to human activities. Here we studied the whistles of bottlenose dolphins (Tursiops truncatus) in two sites of the archipelago of Bocas del Toro, Panama, that contrast in boat traffic. Almirante Bay is a site dominated by taxi-boats and Dolphin Bay is a major location for boat-based dolphin watching. Recordings were made using bottom-mounted hydrophones and from the research boat using an over-the-side hydrophone and a broadband recording system. A total recording effort time of 1,726 h was analyzed. Our results show significant differences in boat detection between sites, and a higher number of whistles detected per minute in the site with tour-boat traffic. Furthermore, whistle modulation accounted for most of the differences between sites, boat presence, and whistle types. Dolphin whistle modulation is thought to be a potential indicator of emotional states including danger, alertness, and stress. In this study, dolphin signature whistle modulation increased significantly with boat presence in both sites but changes in modulation were greater in Dolphin Bay where tour-boats directly and sometimes aggressively interact with the animals. These results support a potential association between whistle modulation and stress (or alertness). These findings indicate that if tour-boat captains behave more like taxi-boat captains by e.g., reducing the distance of approach and contact time during dolphin interactions, dolphin communication, and emotional state would be less disrupted. These measures are implemented in the national guidelines for whale-watching and are known to tour-boat operators. The key to protecting these dolphins is in finding ways to effectively enforce these operator guidelines.