Dead men still tell tales: bivalve death assemblages record dynamics and consequences of recent biological invasions in Kingston Harbour, Jamaica

Abstract

Abstract Short-lived biological invasions may leave lasting impacts on ecosystems well after they have concluded, yet the nature of such events is difficult to elucidate in the absence of monitoring efforts. Here, the ability for surficial death assemblages to recount such invasion events and their ecological legacies was tested using mangrove-dwelling bivalves from Kingston Harbour, Jamaica, where the Asian green mussel ( Perna viridis ) was introduced c. 20 years ago. While rare in Kingston Harbour today, relative densities of dead P. viridis shells mapped well to historical surveys from early into the invasion and thus help reconstruct spatial variations in invasion intensity. Live–dead discordance for the bivalve community further indicated that species have not returned to pre-invasion relative abundance distributions such that the economically-important mangrove oyster ( Crassostrea rhizophorae ) declined while the flat tree oyster ( Isognomon alatus ) rose to dominance. Finally, we report the presence of the charru mussel ( Mytella strigata ) in Kingston Harbour, a newly introduced species that has not yet been significantly incorporated into the subfossil record. This case study exemplifies the utility of underexploited sources of geohistorical data for informing the growing problem of human-assisted biological invasion.