The rippling of human-caused disturbances through complex food webs

We live in the Anthropocene, where humans are the dominant influencers of processes on earth. Fisheries are now one of the most important drivers of marine ecosystem biodiversity. More and more fish stocks are being (over-)exploited in an effort to feed the growing world population. Yet little is known about the interactions between fisheries and the dynamics of the food webs in which the harvested fish are embedded. As these dynamics are complex, single-species management plans must be replaced with models integrating multispecies fisheries, economic market feedbacks, and fisher behaviour into complex ecological interaction networks to promote sustainable resource use. To improve our understanding of how human-caused disturbances spread through food web networks, I investigated the direct effects of fishing on exploited species and the indirect impacts on other species in the same community. I developed a dynamic model that combines resource economics with complex food webs. This model contained one open-access fishery in a complex food web to study how single human-caused disturbances spread, later expanded to three fisheries to explore the impact of multiple sources of perturbation.