Macroalgae

Relevance

The increase in native macroalgae will result in the reduction of grazing pressure by invasive herbivorous fish species, such as lionfish.

Photo: FFI

Results

Native macroalgae is increasing, non-native macroalgae is decreasing.

Interpretation

Since 2008 there has been no recorded increase in native macroalgae cover, however since the establishment of the no-fishing zones, native macroalgae cover has increased, indicating project success.

Methods

Percentage cover is measured in the littoral zone at depths <5 metres. A snorkler places a 20cm x 20cm quadrat on the sea floor randomly along a transect (Citation 1) and takes multiple photographs. Later, a digital grid is applied to each photograph to estimate how many grid cells were occupied by native and non-native macroalagae, thus providing the final variable of percentage cover. This is repeated 10 times along each transect, and XX transects in each of the 3 bays where AKD works. Data is collected twice annually (once in spring and autumn).

Citations

1. Gerakis & Tsiamis, 2014