Na Hang Nature Reserve, Tat Ke Sector - Frontier-publications.co.uk

7b. Formulation used for the assessment of abundance of bird species recorded
in Na Hang nature reserve. (Hill & Kemp, 1996)
Relative abundance of each species within the reserve was calculated from the number
of occasions the species was identified and the average flock size of each species. Set
out in the table below is the format used for assessing abundance. This formulation is
only applicable for the SEE-Vietnam surveys at Na Hang. The abundance rating is
weighted more heavily towards the number of occasions each species was recorded, as
flock size was more difficult to recorded accurately, especially whilst observing large
or mixed flocks.
Average
No. of Occasions Sighted
Flock Size 1 2 3-4 5-8 9-16 >16
1-2 Rare Rare Occasional Frequent Common Abundant
3-8 Rare Occasional Frequent Common Abundant Abundant
>9 Occasional Frequent Common Abundant Abundant Abundant