How to collect a miniSASS Sample
Tools you need
Score sheet, or a piece of paper
Pen / Pencil
Sieve / net (You can make your own Net)
White Tray / Ice cream container
How to be Safe
Rivers may contain various toxins or harmful pollutants. Dangerous animals may also be lurking around. So it is important to cover up your feet.
- Wear Gumboots/Waders/Wellingtons (protecting your feet from the sharp rocks or insects/animals )
- You must have soap to wash your hands and arms after the sampling.
- A life jacket is to be worn for deep waters and strong currents and by non-swimmers.
Terms To Know
Before you get wet and dirty there are important terms you should know.
Rocky/ Sandy rivers - Rivers are termed “rocky” when they have rocks and are usually found at the source of the river.Rivers without any rocks are termed “sandy” and are found at the mouth of the river.
Biotope - A biological habitat type. We look at three types in the miniSASS. Vegetative type has river plants (usually on the sides). Rocky type has small - large rocks. The GSM biotope is the gravel/mud/sand regions of the river.
Best Sites for miniSASS
miniSASS can only be done in rivers and streams. It unfortunately cannot be done on stagnant water like ponds, dams and wetlands. It is very important to check whether the sample area has flowing water, if no then a miniSASS cannot be done there. The best sites for miniSASS are those sections with sand, vegetation and stones available for sampling.
Determine Your Location using GPS
Make sure you fill the Site Information table in correctly, including the GPS Co-ordinates. GPS is a Global Positioning System: A global tool used to determine your accurate position on earth. It is a system of co-ordinates that enables navigation to a particular point. It is very important to have your GPS co-ordinates at the site of the miniSASS, that way we can tell where and which river was sampled. You will require a GPS machine; some cell-phones also provide accurate co-ordinates. Ensure you have noted all the data and figures after the comma, it is important to precisely get the location of the sampling.
The Map accepts the co-ordinates in the format of decimal degrees (-29.26778) and the degrees, minutes and seconds (290 16' 40").
You must get a sample that ranges from all the biotopes in five minutes. For the Rocky biotope you can turn over the rocks and kick them whilst your net is at a downstream position so that all biota that will be released will go directly into the net. When there are some insects on the rock, you can use the river water to put wash them into the net or gently hand pick it and put it into the net.
The GSM biotope is the most fun as you sludge your feet into the mud and dislodge all the sand and mud into the water (use your feet) and run the net in the dirty and muddy water; careful not to get too much mud and sand in the net.
The Vegetative biotope requires that you only sample 2m worth of the biotope, but you can split the 2m all around different types of vegetation that might be present. Also take special care to sample below the water for an accurate result.
Now you must deposit all the sampled biota into the white tray. Halfway fill the tray with water and rinse the net. Carefully use forceps to get the biota that might be clinging to the net and on the leaves or plant debris and place it in the net.
Now look into the white tray filled with a range of organisms that we shall use as data. It is time to pull out the Identification guide as well as the Dichotomous key of macroinvertebrates.
Look carefully at the insects in the tray and try to match them with those in the Dichotomous guide.
When you find a match, mark that insect in the sensitivity table. Do this once for every group that you find. Do this until you are satisfied that you have captured all the different types of insects. Then you can release them back into the river.
How to do the scoring
Each group of microinvertabrates has been allocated a sensitivity score due to their resistance or susceptibility to pollution. A high sensitivity score indicates the high degree of sensitivity and likely not to be present in unnatural river conditions. A low sensitivity score indicates a greater resistance to pollution.
Ensure that you calculate using the Version 2.0 November 2011 pamphlet. Once all these scores have been added up then we take this total and divide it by the number of groups found in order to yield the average score for the river site.
Calculating Your River Health
The miniSASS score calculated above is then cross compared to the Ecological Category table where, depending on the river category your site fits in, we can tell which condition the river is in.
N.B. Even if the result falls under "Unmodified/ natural" Condition this water must still undergo chemical and microbial analysis before it is fit for human consumption. This score measures how environmentally healthy the stream/river is.
As a helpful indicator the turbidity of the river may be tested. This result, although not part of the miniSASS, does provide an idea of the river turbidity at that particular site. A low score indicates that the water is not clean, it carries many suspended solids. A low turbidity indicates the lack of dirt or solids in the river/stream.