NJDEP Bureau of GISAtlantic horseshoe crabs (Limulus polyphemus) are an ecologically significant and imperiled species in the Delaware Bay. Due to overharvesting and habitat degradation and loss, horseshoe crab populations declined and a moratorium on horseshoe crab harvest was imposed in New Jersey in 2008. Recovery efforts are currently underway. One ongoing conservation program is reTURN the Favor (RTF), a large-scale citizen science project where volunteers walk transects of spawning beaches, rescuing horseshoe crabs that have been stranded, overturned, or trapped in natural or manmade impingement hazards before these crabs die from exposure or predation. Derived from RTF volunteer records, this data documents known horseshoe crab spawning beaches on the Delaware Bayshore and the number of crabs rescued by volunteer efforts after being overturned or trapped in different impingements on those beaches. This provides a foundation for identifying structures that constitute a hazard to horseshoe crabs and understanding the relative importance of different beaches and potential impingements in horseshoe crab survival.ArcGIS DynamicMapLayerhttps://hub.arcgis.com/datasets/9c768995442e47948c59a51410e8021d_41engNew Jersey Department of Environmental Protection's (NJDEP) Bureau of GISPublicHorseshoe Crab Total Impingement in New Jersey [New Jersey]Web servicesNew JerseyLast Modified: 2022-08-24