SeagrassNet monitoring across the Americas: case studies of seagrass decline

TLDR: SeagrassNet as discussed by the authors is a monitoring program for seagrasses worldwide, which uses a standardized protocol for detecting change in seagras habitat to capture both seagrase parameters and environmental variables.

Abstract: Seagrasses are an important coastal habitat worldwide and are indicative of environmental health at the critical land–sea interface In many parts of the world, seagrasses are not well known, although they provide crucial functions and values to the world’s oceans and to human populations dwelling along the coast Established in 2001, SeagrassNet, a monitoring program for seagrasses worldwide, uses a standardized protocol for detecting change in seagrass habitat to capture both seagrass parameters and environmental variables SeagrassNet is designed to statistically detect change over a relatively short time frame (1–2 years) through quarterly monitoring of permanent plots Currently, SeagrassNet operates in 18 countries at 48 sites; at each site, a permanent transect is established and a team of people from the area collects data which is sent to the SeagrassNet database for analysis We present five case studies based on SeagrassNet data from across the Americas (two sites in the USA, one in Belize, and two in Brazil) which have a common theme of seagrass decline; the study represents a first latitudinal comparison across a hemisphere using a common methodology In two cases, rapid loss of seagrass was related to eutrophication, in two cases losses related to climate change, and in one case, the loss is attributed to a complex trophic interaction resulting from the presence of a marine protected area SeagrassNet results provide documentation of seagrass change over time and allow us to make scientifically supported statements about the status of seagrass habitat and the extent of need for management action