This paper examines the utility of remotely sensed vs. in situ plot-based monitoring in the Barnegat Bay-Little Egg Harbor (BBLEH), New Jersey, USA estuarine system. We compared the remotely-sensed mapping of seagrass cover change (in 2003 vs. 2009) vs. in situ plot-based monitoring conducted from 2004 through 2009. Comparison of the remotely-sensed vs. the in situ plot-change analysis suggests that the two methodologies had broadly similarly results, with the percent area showing declines in sea grass cover greater than those that exhibited increases. In conclusion, the two studies provide corroborating evidence that sea grass hasrndeclined in percent cover in the BB-LEH system during the decade of the 2000s.