Timing of Predator Arrival

People always say that the early bird gets the worm, but sometimes it may be better for the bird to be fashionably late. In this study we show that interactions between the undersea analogue of the bird and the worm (a carnivorous hawkfish and it’s peanut-sized prey community of small bit fish) are highly dependent on the timing at which predators arrive to the community relative to their prey. We show that later arriving predators more strongly affect prey communities relative to early arriving predators by having greater negative effects on the size of prey communities and modifying prey community composition. Furthermore we demonstrate that predators can promote higher species diversity through increasing the amount of beta diversity (i.e. species turnover). The prevalence of asymmetry in the sequence of species arrival to reefs is highly relevant to marine systems that are often characterized by their high variability in recruitment both within and among different levels of the food web. Collectively our project shows that timing of predator arrival can have demonstrable effects that have been largely ignored in the previous literature on predator-prey dynamics. Furthermore we show novel ways in which natural enemies may promote the coexistence of species in diverse tropical marine systems.

This manuscript represents one in a series of studies that have examined the importance of sequence and timing of species arrival in driving community assembly. Please check out our other papers that feature a guild of competing coral reef fishes.

Geange S.W., J.S. Shima, and A.C. Stier. 2013. An evaluation of competitive effect and response in three species of coral reef fish. 2013. Marine Ecology Progress Series. 472: 239-248. PDF

Geange S.W. and A.C. Stier.2010. Priority effects and habitat complexity affect the strength of competition. Oecologia. 1: 111-118. Abstract. PDF

Geange S.W. and A.C. Stier. 2009. Order of arrival affects competition in two reef fishes. Ecology. 90: 2868-2878. PDF

This paper is led by: Adrian Stier (me) (University of British Columbia) and coauthored by Shane Geange (University of Victoria Wellington), Kate Hanson (American Museum of Natural History), and Ben Bolker (McMaster University). Download the paper here or e-mail me (adrian.stier@gmail.com) for a copy of the manuscript.