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There was a mistake in the Matlab code we used to generate time series solutions of our model, Eqs. (16)-(18). The corrected text below replaces one paragraph on p. 7, and the figures below replace Fig. 4 , Fig. 5 on p. 8. There is no qualitative change to our results. However, there is a quantitative change in the initial dead oyster shell volume B ( 0 ) needed for reef survival. The corrected threshold B ( 0 ) , about 0.40 m3 per m2 of sea floor, is more consistent with a recently experimentally estimated threshold of 0.30 m (Colden, Latour, and Lipcius, Mar Ecol Prog Ser 582: 1–13, 2017) than was our old incorrect threshold of about 0.12 m3.

The literature on climate change education recommends social, accessible action-oriented learning that is specifically designed to resonate with a target audience’s values and worldview. This article discusses GREENIFY, a real-world action game designed to teach adult learners about climate change and motivate informed action. A pilot study suggests that the game fostered the creation of peer-generated user content, motivated informed action, created positive pressure, and was perceived as a fun and engaging experience.

Native oyster populations in Chesapeake Bay have been the focus of three decades of restoration attempts, which have generally failed to rebuild the populations and oyster reef structure. Recent restoration successes and field experiments indicate that high-relief reefs persist, likely due to elevated reef height which offsets heavy sedimentation and promotes oyster survival, disease resistance and growth, in contrast to low-relief reefs which degrade in just a few years. These findings suggest the existence of alternative stable states in oyster reef populations. We developed a mathematical model consisting of three differential equations that represent volumes of live oysters, dead oyster shells (=accreting reef), and sediment. Bifurcation analysis and numerical simulations demonstrated that multiple nonnegative equilibria can exist for live oyster, accreting reef and sediment volume at an ecologically reasonable range of parameter values; the initial height of oyster reefs determined which equilibrium was reached. This investigation thus provides a conceptual framework for alternative stable states in native oyster populations, and can be used as a tool to improve the likelihood of success in restoration efforts.