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Tropical islands, including many in island arcs, are subjected to recurring disturbances from extreme storms such as tropical cyclones. To test whether such storms influence cosmogenic nuclide concentrations such that they do not reflect long‐term rates of erosion, we measured meteoric andin situ¹⁰Be in river sediment samples from Dominica, an andesitic island in the Caribbean, before and after category five Hurricane Maria (in 2017). Populations of before‐ and after‐storm concentrations are statistically indistinguishable (n = 7 pairs forin‐situ¹⁰Be,n = 11 pairs for meteoric¹⁰Be).¹⁰Be concentrations vary from −138% to +73% within before–after sample pairs relative to the mean of the pair. These new data suggest that the effects of extreme storms on the depth and amount of near‐surface erosion on Dominica vary spatially. Our data support the calculations of Niemi et al. (2005) and Yanites et al. (2009) suggesting that basin‐by‐basin comparisons of erosion rates based on cosmogenic nuclides should be approached with caution in small (<~100 km²) watersheds affected by mass movements and extreme storms. Erosion rates determined fromin‐situ¹⁰Be on Dominica (geometric mean = 0.102 mm y⁻¹,n = 12) are low compared to similarly steep and wet areas globally and correlate positively with the spatial density of mass movements.