Aquatic macrophytes provide
critical nursery habitat, refuge from predators, and
critical habitat for aquatic invertebrates and fish
within lakes, streams, and marine environments. Hydroacoustics
provide an efficient method for determining the spatial
distribution and extent of submerged macrophyte beds.
Measurements such as stem height and weed-bed volume
can be derived from the collected hydroacoustic survey
data. This type of information can be used to monitor
temporal changes in macrophytes, which can further
be compared to, for example, the spatial distribution
of fish and invertebrates and environmental variability.
1. Example from an echogram recorded from the
Lac La Biche (Alberta) hydroacoustic survey showing
an area of submerged aquatic macrophytes. The
thick green line denotes the acoustically determined
depth of the top of macrophyte stems.
2. The spatial distribution of submerged macrophytes
on Lac La Biche (Alberta). Data points shown are
the average stem heights within a 5 m EDSU along
the survey transect.