Crowding in marine environments: Divers and whale watchers in the Azores

•Expected absence of crowding is important for the destination choice Azores.•Satisfaction reduced among crowded divers but not among crowded whale watchers.•Specialization increases crowding of divers but not of whale watchers.•Crowding does not increase perceived environmental impacts.•Unacceptable use levels are approached with some islands more affected by crowding.

Increasing numbers of visitors in marine environments have resulted in a growing importance of social impact understanding such as crowding. This study examines perceived crowding of divers and whale watching tourists in the Azores. Reported encounters and encounter norms for both whale watching boats and divers were studied and minimum acceptable conditions for both activities determined. Perceived crowding was not correlated to specialization of users and only impacted the overall satisfaction of divers. The satisfaction of whale watchers was not altered through perceived crowding. Environmental impacts were not perceived differently by participants reporting different levels of crowding. The five different case study islands showed different levels of crowding. Management interventions to contribute to sustainable and satisfactory marine wildlife experiences include spatial zoning, achieving higher compliance with existing regulations, improved educational and awareness programs and limiting the number of divers at some dive sites.