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Surveying and sampling in streams

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Sampling in a stream with nets

The Conservation Volunteers joined Lagan Valley Regional Park staff and volunteers to provide training in pond surveying and river sampling.

With help from Ron, a Volunteer Officer with TCV, participants used nets to collect invertebrate samples from the pond at Minnowburn, National Trust, Belfast.

Firstly participants identified the many different microhabitats found within the pond ecosystems; these included; open water, areas shaded by trees, stands of reedmace and branched bur-reed, deep and shallow water. Guidance indicates that the total netting time to sample a pond in three minutes spread evenly across the different habitats.

The group identified eight different habitats and spent 22 seconds sampling with nets. A wide range of macro-invertebrates were collected and sorted at the pond edge. Typical species included Sticklebacks, water snails, water boatmen,  pond skaters, water beetles, rams horn snails, pond snails, common newt, caddis fly cases and nymphs.

The group used keys to identify all species found. After a quick tea break we moved a short distance to another freshwater habitat, Purdysburn stream. This time the team used another sampling technique called ‘kick’ sampling. This involves kicking the substrate to disturb any invertebrates so that they can be caught by the hand net. In flowing water the net is placed downstream so that the invertebrates are swept into it. Sampling is usually standardised by collecting each sample over a 3-minute period. The samples were sorted and species record. Water shrimp, gudgeon, mayfly nymphs, bloodworms and sticklebacks.

This training will allow Lagan Valley Regional Park staff and volunteers to complete monitoring of freshwater habitats within the AONB.

TCV runs various training events to help better manage for our biodiversity throughout the year