Estimating basal area coverage of subtidal sea grass beds using underwater videography

This study presents a new method of estimating basal area coverage of subtidal vegetation. It makes use of differential global positioning system data in conjunction with underwater video imaging. This technique is able to both qualify and quantify sea grass habitats not visible by the traditional methods of aerial photography and satellite imagery. However, several limitations apply. Shallow, turbid waters or large regions cannot be sampled; GPS errors must be accounted for; and measurements of sea grass density are subjective.