Typical abundance

Typical abundance scale

Rank Definition
High density Species that are found in high numbers in their appropriate habitats. Equivalent to Superabundant and Abundant on the MNCR SACFOR abundance scale (see below).
Moderate density Species that are found in moderate numbers in their appropriate habitats. Equivalent to Common and Frequent on the MNCR SACFOR abundance scale (see below).
Low density Species that are found in low numbers in their appropriate habitats. Equivalent to Occasional and Rare on the MNCR SACFOR abundance scale (see below).
Very low density Species that are found in very low numbers in their appropriate habitats. Equivalent to less than Rare on the MNCR SACFOR abundance scale (see below).

Marine Nature Conservation Review (MNCR) Abundance Scales

S = Superabundant, A = Abundant, C = Common, F = Frequent, O = Occasional, R = Rare, L = Less than rare indicated by extrapolation.
Cover Growth form Size of Individuals or Colonies Density scale
Scale(%) Crust or Meadow Massive or Turf <1 cm 1-3 cm 3-15 cm >15 cm Density other
>80% S   S       > 1 / 0.001 m2 (1 x 1 cm) >10,000 / m2
40 to 79% A S A S     1-9 / 0.001 m2 (10 x 1 cm) 1,000-9,999 / m2
20 to 39% C A C A S   1-9 / 0.01 m2 (10 x 10 cm) 100-999 / m2
10 to 19% F C F C A S 1-9 / 0.1 m2 10-99 / m2
5 to 9% O F O F C A 1-9 / m2  
1 to 5% or density R O R O F C 1-9 / 10 m2 (3.16 x 3.16 m)  
<1% or density L R L R O F 1-9 / 100 m2 (10 x 10 m)  
    L   L R O 1-9 / 1000 m2 (31.6 x 31.6 m)  
          L R <1 / 1,000 m2 (100 x 100 m)  
            L <1 / 10,000 m2 (1 km2)