Griffin Srednick

All Publications

• Spatial Portfolios in Coral Metapopulations Are Shaped by Spatiotemporal Asynchrony in Environmental Conditions. Ecology letters Srednick, G., Davis, K., Edmunds, P. J. 2026; 29 (2): e70324

  Abstract

  Identifying the drivers and timescales of population synchrony is critical for understanding metapopulation resilience. Using wavelet analyses of a 19-year coral community timeseries from Moorea, French Polynesia, we quantified timescale-specific population synchrony in four common coral genera and evaluated the predictors of spatial portfolio effects. We detected synchrony within genera associated with synchrony in degree heating days, diurnal temperature range (DTR) and macroalgal cover at different timescales. Synchrony in DTR and macroalgal cover was associated with lower synchrony of Pocillopora and Porites populations, respectively. Population (for three of four genera) and environmental synchrony were stronger within than among habitats across timescales, underscoring the role of habitat-specific conditions in driving spatial synchrony and spatial portfolios. These results describe how the spatial and temporal scales of heterogeneity in environmental and ecological conditions determine synchrony in coral population dynamics and support a spatial portfolio effect, which may buffer coral metapopulations from island-scale collapse.

  View details for DOI 10.1111/ele.70324

  View details for PubMedID 41622513

• Long-term community dynamics are heterogeneous between fringing- and fore-reef habitats on an Indo-Pacific coral reef ECOSPHERE Edmunds, P. J., John, C., Leichter, J. J., Moritz, C., Scafidi, K. C., Speare, K. E., Srednick, G., Wyatt, A. J. 2025; 16 (10)

  View details for DOI 10.1002/ecs2.70398

  View details for Web of Science ID 001598826100001

• Habitat attributes mediate top-down and bottom-up drivers of community development in temperate and tropical algae ECOSPHERE Srednick, G., Swearer, S. E. 2025; 16 (8)

  View details for DOI 10.1002/ecs2.70345

  View details for Web of Science ID 001543416200001

• Asynchrony in coral community structure contributes to reef-scale community stability SCIENTIFIC REPORTS Srednick, G., Davis, K., Edmunds, P. J. 2023; 13 (1): 2314

  Abstract

  Many aspects of global ecosystem degradation are well known, but the ecological implications of variation in these effects over scales of kilometers and years have not been widely considered. On tropical coral reefs, kilometer-scale variation in environmental conditions promotes a spatial mosaic of coral communities in which spatial insurance effects could enhance community stability. To evaluate whether these effects are important on coral reefs, we explored variation over 2006-2019 in coral community structure and environmental conditions in Moorea, French Polynesia. We studied coral community structure at a single site with fringing, back reef, and fore reef habitats, and used this system to explore associations among community asynchrony, asynchrony of environmental conditions, and community stability. Coral community structure varied asynchronously among habitats, and variation among habitats in the daily range in seawater temperature suggested it could be a factor contributing to the variation in coral community structure. Wave forced seawater flow connected the habitats and facilitated larval exchange among them, but this effect differed in strength among years, and accentuated periodic connectivity among habitats at 1-7 year intervals. At this site, connected habitats harboring taxonomically similar coral assemblages and exhibiting asynchronous population dynamics can provide insurance against extirpation, and may promote community stability. If these effects apply at larger spatial scale, then among-habitat community asynchrony is likely to play an important role in determining reef-wide coral community resilience.

  View details for DOI 10.1038/s41598-023-28482-7

  View details for Web of Science ID 000988268200086

  View details for PubMedID 36759628

  View details for PubMedCentralID PMC9911750

• Habitat attributes mediate herbivory and influence community development in algal metacommunities ECOLOGY Srednick, G., Cohen, A., Diehl, O., Tyler, K., Swearer, S. E. 2023; 104 (4): e3976

  Abstract

  Understanding the drivers and impacts of spatiotemporal variation in species abundance on community trajectories is key to understanding the factors contributing to ecosystem resilience. Temporal variation in species trajectories across patches can provide compensation for species loss and can influence successional patterns. However, little is known about the underlying mechanisms that lead to patterns of species or spatial compensation and how those patterns may be mediated by consumer-resource relationships. Here we describe an experiment testing whether habitat attributes (e.g., structural complexity and spatial heterogeneity) mediate the effects of herbivory on tropical marine macroalgal communities by reducing accessibility and detectability, respectively, leading to variable trajectories among algal species at community (within patch) and metacommunity (i.e., among patch) scales. Reduced accessibility (greater habitat complexity) decreased the effects of herbivory (i.e., depressed consumption rate, increased algal species richness), and both accessibility and detectability (spatial heterogeneity) influenced algal community structure. Moreover, decreased accessibility at the community scale and a mosaic of accessibility at the metacommunity scale led to variation in community assembly. We suggest that habitat attributes can be important influencers of consumer-resource interactions on coral reefs, which in turn can increase species diversity, promote species succession, and enhance stability in algal metacommunities.

  View details for DOI 10.1002/ecy.3976

  View details for Web of Science ID 000931346200001

  View details for PubMedID 36691779