Abstract
Parasites and diseases affect the population dynamics and community structure of marine organisms; however, their distribution and impacts are far from uniform across taxa or on large spatial scales. As global environmental changes threaten to shift the ranges of disease agents across the world’s oceans, it is imperative to identify the large-scale patterns of marine parasitism and to uncover the processes driving those patterns. In this chapter, the authors present a conceptual framework and review empirical evidence regarding the biogeography and macroecology of marine parasites. They examine how parasites fit classical biogeographical rules, from latitudinal gradients to the distance decay of similarity in community composition. They also discuss how host species traits can influence the diversity and severity of their parasite infections and whether spatial variation in host community diversity can account for hotspots of parasite diversity. The focus then turns to emerging marine diseases and whether there are large-scale patterns in where and how they arise. Lastly, they discuss the major data gaps and future challenges facing scientists tasked with anticipating and mitigating future disease outbreaks in tomorrow’s oceans.