Maerl is a free living, coralline red algae which forms loose-lying beds. Scotland is home to some of the most extensive maerl beds in Europe. These fragile beds are disproportionally biodiverse compared to the surrounding seabed and are home to some species which are not found elsewhere. Maerl beds are Priority Marine Features. High resolution photogrammetry allows for the calculation of niche availability within the beds, and the flow modification of seawater by their intricate structures.