Dear colleagues, We are pleased to announce the publication of our recent studies on whale-watching activities on humpback whales off Reunion Island in the Indian Ocean, available Open Access in Tourism in Marine Environments: 1) Hoarau, L., Dalleau, M., Delaspre, S., Barra, T. & Landes, A.E. Assessing and Mitigating Humpback Whale (*Megaptera Novaeangliae*) Disturbance of Whale-watching Activities in Reunion Island. Tourism in Marine Environments <https://www.ingentaconnect.com/content/cog/tme>, Volume 15, Numbers 3-4, 2020, pp. 173-189(17). https://doi.org/10.3727/154427320X15943326793398 2) Barra, T., Bejder, L., Dalleau, M., Delaspre, S., Landes, A.E., Harvey, M. & Hoarau, L. Social Media Reveal High Rates of Agonistic Behaviors of Humpback Whales in Response to Swim-with Activities Off Reunion Island. Tourism in Marine Environments <https://www.ingentaconnect.com/content/cog/tme>, Volume 15, Numbers 3-4, 2020, pp. 191-209(19). https://doi.org/10.3727/154427320X15960647825531 The corresponding abstracts are found below: 1) Assessing and Mitigating Humpback Whale (*Megaptera Novaeangliae*) Disturbance of Whale-watching Activities in Reunion Island. Whale watching, including swim-with-whales activities, is developing at an enormous rate in Reunion Island. This is raising concerns about its impacts on breeding humpback whales and challenging the sustainability of the activity. In 2017, a dedicated-at-sea patrol team, "Quiétude," was created to observe, monitor, and raise awareness to the whale watchers in order to improve compliance with local guidelines. In this context, the team assessed whale watching in Reunion Island during two humpback whale breeding seasons in 2017 and 2018, between June and October. Sighted groups were mostly composed of mother/calf pairs spending most of their time resting near or at the surface. Whale-watching vessels were present in 85.1% of sightings, of which 68.4% were recreative. Swimwith-cetaceans activities were very frequently observed in 42% of sightings. Overall, compliance with the charter was as high as 68% of whale sightings with vessels/swimmers were in line with the recommendations. However, low compliance (32.8%) was observed with the specific recommendations of swim-with-cetaceans activities. Swimmers were reported in surface active groups displaying agonistic behaviors, which poses evident human safety concerns. Humpback whale resting behaviors were disrupted significantly by whale-watching activities. Humpback whales tended to avoid vessels and swimmers, especially when their behavior was intrusive or not compliant with the charter. Positive humpback whale responses were more likely to occur if the charter's recommendations were not breached. Our results highlight how a nonbinding regulation, with recommendations scrupulously pursued, allows for a reduction in whale-watching disturbances and supports a better tourism experience. Our results advocate for reinforcing tourism education, whale-watching adaptive management and regulations, specifically for vulnerable groups with a calf, and for the swim-with-whales activities. This could be efficiently achieved by engaging all stakeholders and the permanent team on the field "Quietude" to enhance dissemination of best practices and sensitivity around sustainable values of implemented regulations. 2) Social Media Reveal High Rates of Agonistic Behaviors of Humpback Whales in Response to Swim-with Activities Off Reunion Island. The effect of nature-based tourism on wildlife has been the focus of much attention. Studies have demonstrated how boat-based cetacean-watching tourism can cause both short-term and long-term effects on targeted populations. However, limited attention has been given to the effect of swim-with activities on humpback whales (*Megaptera novaeangliae*). This study qualified whale responses to swim-with activities off Reunion Island during the 2018 humpback whales breeding season. We used both under- and above-water videos collected from social media outlets, commercial whale-watching operators, and audiovisual professionals. We documented a high rate of agonistic whale behaviors (during 42.1% of all observations; * n* = 164) towards swimmers within videos containing swim-with events. We documented seven agonistic behaviors including threat, attack, or defense behaviors that were predominantly exhibited by mother/calf groups (73.8%; * n* = 121) and by singletons (16.5%;* n*= 27). Pectoral shears (27.4%) and fluke thrashes (23.2%) were the most exhibited agonistic whale behaviors aimed towards swimmers, both of which pose a danger and serious injury to swimmers. During swim-with attempts whales changed their behavioral state (82.3%,* n* = 159) and used avoidance tactics to avoid swimmers (56.1%,* n* = 92). Whales exhibited a higher rate of agonistic behaviors when swim groups were active and dispersed, in contrast to when they were quiet and compact. To mitigate whale disturbance and improve swimmer safety, we recommend avoiding swimming with whale groups containing calfs. Our findings support the implementation of strong regulations and educational tools to ensure a sustainable practice of whale watching off the Reunion Island. Please do not hesitate in contacting us at this email address for any questions. All the best, *Equipe Quiétude - Observation respectueuse des cétacés et tortues marines à La Réunion* https://cedtm-asso.org/quietude/ *>> 100 Mesures pour dessiner l'avenir de l'activité d'observation des cétacés à La Réunion ? Découvrez, soutenez, participez ! <https://cedtm-asso.org/quietude/mesure/>* *Centre d'Etude et de Découverte des Tortues Marines (CEDTM)* Rés. M. Rishna, Appt 5 - 6, chemin Dubuisson <https://drive.google.com/open?id=1UoHvQs0TpUyzyE9N7rV-vZTOiEc> 97436 Saint Leu, La Réunion Tel : (+262) 02 62 91 35 28