How to survey using SACFOR
The presence or absence of a species might be valuable if a thorough search is carried out (e.g. from within a set of randomly placed squares) within a particular area or less than common species or features of the MPA can be found and recorded (e.g. during a timed search).
However, so far, the walkover surveys have been used to build confidence and ID knowledge, but the data is limited. Recording species along a transect/walked area can be collecting much more valuable data, if species abundance is collected as well.
Scales of abundance require well-developed species knowledge in order to be able to assign what you’re looking at to groups (e.g. based on growth form) before commenting on abundance. However, since it helps to build knowledge of species and how they tend to grow there is a twofold reason for incorporating it into the Walkover surveys in Shoresearch Cymru Level 2.
We will soon have a test session here for you to get some practice in before attempting the same on shore.
Using the SACFOR scale
The SACFOR scale is one such scale and is used by a lot of different organisations. The name is an anagram of words describing the levels:
S Superabundant
A Abundant
C Common
F Frequent
O Occasional
R Rare
and there is an
L Less than rare (no longer used)
Using estimation can be very subjective, so time needs to be taken to practice. You will have a sheet with the scale with you as you’re surveying. Pay attention to each specific column and assign once you’ve got a clear idea of area and species growth form.
The scale provides a choice of level of abundance in line with species grouped according to how they grow, to provide a more appropriate estimation of cover and counts. For instance, using the same measure of “frequent” for canopy cover algae as sea squirts is not sensible. Sea squirts are instead in a few groupings depending on the size they tend to grow as individuals or colonies.
As well as getting to grips with how to decide on species growth form, you might also need to get to grips with the spatial units used. For a start, the quadrats we’ve been using on our group surveys have sides measuring ½ metre. This might make you think that makes the area you’re surveying 0.5m2 but it doesn’t. This mistake is common and might come from knowing that a quadrat with sides measuring 1metre does cover an area 1m2 . Unfortunately, the actual area feels counter-intuitive as 0.5mx0.5m is o.25m2. You can help yourself by keeping in mind the numbers in brackets on the SACFOR scale (replicate the scale like the one in Strong and Johnson).
To help to a degree, we will provide sheets with the smaller scaling on together with the SACFOR table to use as you’re recording.
As you can see, there’s a lot to trip up on, so this will slow down your Walkover surveys. This information, when mastered, will provide much more valuable data, so the on-shore practice will not be wasted, here.
To move through the training, you will need to provide 4 completed walkover surveys with SACFOR abundance. So, this will hopefully provide adequate practice.
We have a practice session on its way here, so please keep checking back.