ECOFACT staff took these underwater photographs and video footage in the River Roughty, Co Kerry, last week. These images were recorded while surveying for Freshwater Pearl Mussels on behalf of Kerry County Council and the National Parks and Wildlife Service.
Although the survey was for Freshwater Pearl mussels, we saw lots of salmon, trout and sea trout. Snorkelling is a great non-invasive method for surveying fish populations in rivers and the method is widely used in the USA to monitor ﬁsh populations in streams and to estimate both relative and total abundance. Snorkelling can also be used to assess ﬁsh distribution, presence/absence surveys, species assemblages and some stock characteristics (i.e. presence of different age groups of fish), and habitat use. This technique is particularly well suited to survey juvenile salmonid populations, due to their territorial nature in freshwater and propensity for using clean streams. As is apparent from the video below, the method can be easily applied in a clean river like the Roughty.
For more information on snorkelling surveys for fish populations see the following link.
If you require any further information on fisheries surveys offered by ECOFACT please do not hesitate to contact us.