Recruitment pulses cause a market dilemma in cleaning interactions from a tropical Atlantic rocky reef

Cleaning associations are mutualistic interactions in which an organism (called cleaner) removes parasites and dead skin from another (called client), gaining an energetic food source in exchange. Some species are quite specialized for performing cleaning interactions through their lives (called dedicated cleaners), though most cleaners interact during juvenile life stages (called facultative). Here, we describe how changes in populations of dedicated and facultative cleaners could affect the structure of the cleaning interactions using data from a rocky reef in the Southwestern Atlantic. Over three consecutive years, Elacatinus figaro (dedicated cleaner) was the most important cleaner within the local cleaning network despite its low abundance. Meanwhile, facultative cleaner species showed erratic population structures with a similarly oscillating importance in the interaction network. Given the extent of these changes, we suggest the fluctuation in the abundance of facultative cleaners can have a significant impact on the cleaning network structure, with clients adapting to changes in the availability of cleaning services by different cleaner species. The interactions highlight the generalist nature of cleaning associations but also reveal that both cleaner and client species may actively choose their clients based on which species could provide the best services. Given these factors, we find it reasonable to assume cleaning interactions in Arraial do Cabo fits well within the market dilemma framework, as clients and cleaners perform different strategies to improve their benefits.