Prior predation alters community resistance to an extreme climate disturbance

Abstract

Citation: Jurgens, L. J., A. L. Freestone, G. M. Ruiz, and M. E. Torchin. 2017. Prior predation alters community resistance to an extreme climate disturbance. Ecosphere 8(10):e01986. 10. 1002/ecs2.1986 Abstract. Short-term physical disturbances occur amid a backdrop of longer-term biotic interactions, including predation, which shape communities. Effects of consumer interactions typically begin in early stages of assembly and continue throughout post-disturbance recovery. Despite decades of predation and disturbance research, few studies examine how consumer interactions during these different time periods may affect community responses to disturbance. Here we use replicate communities of tropical, sessile invertebrates to ask whether fish predation during initial assembly (before) and recovery (after) influences community resistance to a hurricane-level low-salinity event. Results revealed that pre-event predation determined whether communities shifted in biomass and community structure following disturbance. Communities that assembled without predators responded to the low-salinity event strongly, with large shifts in community composition and a mean loss of 54% of pre-disturbance biomass after a one-month recovery period. In contrast, those that experienced predation during initial assembly were strikingly resistant to disturbance, which had no effect on species composition or biomass. Results were driven by predator removal of a dominant competitor, which gave rise to more disturbance-resistant communities. These findings highlight the potential for past trophic interactions to shape community stability in the face of physical disturbances predicted to escalate with global change.

Persistence and space preemption explain species‐specific founder effects on the organization of marine sessile communities

“…This species exhibited the lowest persistence, likely as a result of low‐survival rate and the lack of conspecific cues leading to colony clusters and thus the formation of larger and more resistant patches. Low resistance to predation, as previously observed for ascidians in the study area (Oricchio, Flores, & Dias, ; Vieira et al., , ) and elsewhere (Jurgens, Freestone, Ruiz, & Torchin, ; Osman & Whitlatch, ) may have played an important role. As such, we conclude that potentially strong competitors, as B. nigrum , may impose very limited priority effects on community structure because they fail to persist under average environmental conditions.…”

“…This species exhibited the lowest persistence, likely as a result of low-survival rate and the lack of conspecific cues leading to colony clusters and thus the formation of larger and more resistant patches. Low resistance to predation, as previously observed for ascidians in the study area Vieira et al, 2012Vieira et al, , 2016 and elsewhere (Jurgens, Freestone, Ruiz, & Torchin, 2017;Osman & Whitlatch, 2004) (Jackson & Hughes, 1985;Kay & Keough, 1981), which face a high risk of being dislodged or overgrown (Nandakumar, 1996;Russ, 1982). The high-survival rate observed here coupled with the wellknown resistance against predators (Lidgard, 2008;Oricchio, Pastro et al, 2016) resulted in remarkable persistence of S. errata growing colonies, rendering pervasive effects on community structure, which may last until any disturbance event results in the detachment of aged colonies.…”

Calcareous defence structures of prey mediate the effects of predation and biotic resistance towards the tropics

“…While the abiotic resistance in temperate regions is prone to be weakened by global changes on a long-term basis (Mahanes & Sorte, 2019;Ruiz et al, 2000), the biotic resistance to invasion in tropical communities is already being threatened by the severe reduction in the diversity and abundance of fish promoted by human activities, such as overfishing and habitat degradation (Coleman & Williams, 2002;Llope et al, 2011). Reduction in predatory fish, allied to less restrictive physical Oricchio, Pastro, et al, 2016;Osman & Whitlatch, 2004;Vieira et al, 2012), including introduced species (Freestone et al, 2013;Jurgens, Freestone, Ruiz, & Torchin, 2017;Kremer & Rocha, 2016). Instead, strategies to avoid predation by non-calcified organisms may rely on escape in time, with colonial animals being able to asexually regrow after predation when colony tissue is partially damaged (Hiebert, Vieira, Dias, Tiozzo, & Brown, 2019;Jackson, 1977;Jackson & Coates, 1986).…”

Community regulation models as a framework for direct and indirect effects of climate change on species distributions

“…Interacting species often do not undergo range shifts in unison (Harley 2011), which could lead to the exclusion of some species in a community if they are unable to keep pace. Additionally, these models do not include larger scale (e.g., meta-population) dynamics (Menge and Olson 1990), community shifts due to disturbance (Jurgens et al 2017) or direct human impacts, such as deforestation or habitat fragmentation. More complex community regulation models would be required to account for the effects of multiple environmental stressors, which themselves can have interactive ecological effects.…”