The ongoing and interactive effects of climate change, overharvesting, and habitat loss on fish and fisheries impacts a wide array of stakeholders who rely on access to sustainable fish populations for their health, recreation, well-being, and income. Successful responses to these threats will require the involvement of stakeholders in co-developing solutions. Understanding the socio-psychological characteristics of these diverse stakeholders, including their environmental attitudes and behaviors, can potentially improve management support and effectiveness across and within these groups. Past research has focused on climate impacts and adaptation efforts in commercial fisheries, but less is known about climate-related perceptions and attitudes of recreational fishers and other stakeholders such as citizen scientists. This study investigated how pro-environmental attitudes (PEAs), pro-environmental behaviors (PEBs), and climate change concerns vary among fisheries-based recreationists based on activity type (recreational fishing, fish monitoring for citizen science) and specialization level. Among stakeholders, citizen scientists (fish counters) exhibited the strongest PEBs, followed by more specialized recreational fishers. Citizen scientists also had stronger PEAs than recreational fishers and non-fisher/non-citizen scientists, but there were no significant differences in PEAs across specialization levels. Citizen scientists showed greater concern for climate change than recreational fishers and non-fisher/non-citizen scientists. However, respondents overall showed greater concern for “the environment” than for climate change. Our results suggest that both activity type and specialization level are important considerations when developing strategies to promote pro-environmental behaviors and climate concerns and that communication frames centered on healthy ecosystems may be more effective with some stakeholders than those focused solely on climate change. We discuss implications for building public support of climate engagement efforts and sustainable, climate-resilient fisheries.