Abstract: A central feature of many cooperatively breeding birds is that maturing juveniles not immediately able to obtain a breeding position often become helpers who assist in rearing the offspring of others. In some but not all such species, some juveniles instead become floaters, living singly rather than as part of a group. Being a floater is typically viewed as suboptimal compared to being a helper due to lower survival and the absence of inclusive fitness gains, but data on floaters are few. Here, we use long-term demographic data from the red-cockaded woodpecker to evaluate the effects of helpers (sex and relatedness) and floaters (sex and affiliation) on eight breeder fitness components that may indirectly alter their own fitness. In addition to these indirect effects, we also evaluated the direct effects of these two living strategies on their own survival, ability to obtaining a breeding position, and ability to obtain a high-quality territory. In support of inclusive fitness theory, helpers more related to the breeding pair made greater contributions to six breeder fitness components, whereas unrelated helpers and floaters had exclusively negative impacts on breeder fitness. In regards to direct fitness consequences, helpers had higher survival at a cost to acquiring a breeder position, whereas floaters had lower survival with a higher probability of acquiring a breeding position. Here, we demonstrated two aspects of alternative living strategies. First, floating and helping may exist along a spectrum of cooperation and antagonism based on helper relatedness and floater affiliation. Second, floaters generally adopt a high-risk, high immediate reward strategy, whereas helpers may adopt low-risk, low immediate reward strategy.
