We have conducted fish surveys on samples from ponds, lakes, rivers, estuaries, coastal areas and the open ocean; from the equator to the North Pole.
Accurately monitoring fish communities is time consuming, costly, and often stressful for the animals concerned. Moreover, it requires a great deal of survey effort to detect the full range of species present at a site.
eDNA is faster (in terms of field time) and cheaper than traditional survey methods. It is highly sensitive and has no physical impact on animals or the environment. Research groups worldwide report that eDNA metabarcoding can be more sensitive and powerful than any conventional approach to surveying fish communities.
Our Fish Survey service uses metabarcoding of the 12S gene to characterise the fish diversity in an eDNA sample. The primers are specific to fish, and we use a custom bioinformatics pipeline together with a curated reference database of fish sequences to return high confidence detections. Turnaround time is up to 8 weeks, but large numbers of samples can be processed in parallel.
Because this service uses the metabarcoding approach, we are not testing for the presence of particular fish species ("is species X present?") but instead we are sequencing all of the fish DNA in the sample and identifying it to ask "which fish species are present in this sample?". The species we can identify depend on the completeness of reference databases. In Europe, we can identify the vast majority of freshwater species and a good proportion of marine ones. Below is a list of the species that we have found in water samples in recent months (British & European freshwater and coastal samples):
Fish shed DNA into the water all year round, and so can be monitored throughout the year. However, it may be best to avoid the breeding season when egg releases can cause huge spikes in the amount of DNA of particular species, potentially shrouding other species from detection. It is likely that the DNA results will most accurately reflect relative abundance of the fish during the autumn and winter months.