I have a dated report on my Researchgate, concerning use of aquatic insects as a indicator of pesticide spray concerning spruce budwom. If has a moth on the cover of the report, put out in 1983 or 1984. It may give you ideas and I doubt if the collection methods have changed much, but I am unsure of the detail used.
Unified standard procedure for every purpose doesn’t exist. Why? You have to do with different water bodies, basins, artificial ponds, marine, shallow and deep water habitats. So, should limit the circle to the object.
1) Object. Creek, spring, river, pond etc.
2) Sampling net. Upper reaches, middle, lower if watercourse, transect over the pond or lake.
3) Sampling station amount is depending on scale (size) of object.
4) Frequency of sampling. Depends on the main goal and aims of study.
5) If monitoring: short term needs mass sampling, long term should select basic stations, and other like control. Should cover seasons. Winter is the very important as sometimes in running waters of esp mountain areas life is very active this period. Even primary production is maximum!
6) Minimum sampling to have dynamic is 5-6 per year.
7) For taxonomic purposes may be not so frequently but find not typical biotopes.
8) If lake or pond should use Petersen or other sampler. If brook or stream – can use plastic (better) or glass jar with scaled area of sampling. For pebble we are using the following method: clean the stone from both sides by tooth brush in photo (or other) flat small basin, and measure its volume (sample) to have possibility to recalculate for the area.
9) Use subsamples from this sample to calculate in camera. We use Bogorov camera for larvae of insects.
10) Can fixate by formaldehyde or investigate alive, though keep in freezer.
11) Calculate all, should immediately identify into groups, specimens should store in concave glass in solution of glycerin to avoid desiccation.
This approach gives you possibility to differ different trophic levels and groups that is extra important in Hydrobiology, eg. to differ predators incide taxocoenosis, level of consumption of primary production at al.
If good identification minimum into Genera, so can use automativ regime of calculation (if have some program). We have in DOS turbo-basic elaborated with perfect database.
As already suggested, most methods depend of the scope you want to perform. Some textbooks such as Merritt & Cummins or Thorp & Covitch provide plenty of references how to collect aquatic macroinvertebrates. You may also discuss this issue with some of your Nigerian colleagues, such as Imoobe in Benin City for instance. In any case, try to avoid formaldehyde for fixing your material, and prefer ethanol at 85-95%. Otherwise, your material will be too hard to be prepared for a good identification, and DNA will be destroyed if you intend to do some barcoding or other analyses.
In addition to the suggestions already provided, you may need to employ grab if your research concerns benthic invertebrates, especially molluscs, annelids, etc.
You can find diverse standars in the following documents (UNE normative):
EN ISO 10870:2012. Water Quality - Guidelines For The Selection Of Sampling Methods And Devices For Benthic Macroinvertebrates In Fresh Waters
EN ISO 5667-1:2007. Water quality - Sampling - Part 1: Guidance on the design of sampling programmes and sampling techniques
EN 14996:2006. Water quality - Guidance on assuring the quality of biological and ecological assessments in the aquatic environment
EN ISO 8689-1:2000. Water quality - Biological classification of rivers - Part 1: Guidance on the interpretation of biological quality data from surveys of benthic macroinvertebrates.
EN ISO 8689-2:2000. Water quality - Biological classification of rivers - Part 2: Guidance on the presentation of biological quality data from surveys of benthic macroinvertebrates
EN 16150:2012. Water quality - Guidance on pro-rata Multi-Habitat sampling of benthic macro-invertebrates from wadeable rivers
CEN/TC 230 N620 – NWIP – Working Document: prEN Multihabitat: 2009. Water Quality – Guidance on pro-rata Multi-Habitat sampling of benthic macro-invertebrates from wadeable rivers.
You must specify what you are interested in invertebrates. They are completely different procedures and methods of sampling seston, benthos and nektonu. Perhaps it is enough to set up a scuba suit and arm yourself with a fotocamera or a video camera and documented life under the water without catching invertebrates? First you need to clearly define the purpose of the sampling - whether it's just an exercise and pre-knowledge of the sea life - in its bottom starting from arenal, littoral or benthal neritic zone to bathybenthal and midwater - whether they are professional or studying the ecology of marine biology? Some were more fascinated by life in the water column and other seabed? Secondly, you need to determine how long it will result in a discovery or is it a one-time observation and there may be just one sampling during the growing season? if we set a regular survey of the sea for a longer period of time (a minimum of two years "with time to spare for 2 seasons") and perhaps more important 24 hour tests eg. every hour the water column to know the vertical migration of addicts phototaxis at night and during the day. Here comes another problem, whether they are observations only qualitative or quantitative well? Thirdly, we evaluate whether enough samples on invertebrates in the littoral zone and here you do not need to have a special floating means, whether we are interested in sea life close to shore and maybe more than a few miles, it is important how deep we want to watch marine life. And in the end - we must have the right tools for the intended research: batometer, samplers, nets, etc., suitable clothing and footwear (not always the sea the sun is shining, it is often windy and storm). It's just as much the most important questions
As already suggested, there are different methods depending on your goals, environments, etc.. I attach a Chapter on Methods for aquatic and terrestrial invertebrates that can be of your help.
We have standard protocols for sampling macroinvertebrates in wadeable streams for New Zealand. Different methods for qualitative/quantitative and different stream types (cobble vs. soft sediment). You will need to decide if they are relevant to your stream types and research questions.
Dear Andem, I don't think there's more to be added to what has been suggested above. Just decide on the type of benthos you want to sample, which water body you want to do your sampling and the state in which you need the sample and you will have enough approaches available at your disposal if only you could afford them. Some methods could be improvised depending on the situation you find yourself.
Where are you collecting and why? Regardless of technique, you need consistency and enough numbers to answer your questions. Give us details and we'll give you amazing answers.