How do I use the Mini-Surber Sampler?
1. While setting and sampling with the surber, be careful not to disturb the substrate upstream from the sample area. This could cause organisms from outside the sample area to be caught in the net.
2. Set the surber with the net upright, water flowing into the net. The water cannot flow over the top of the net or some of the sample could be lost downstream.
3. Set the open frame on the stream bottom, marking off the area to be sampled.
4. Being careful not to disturb the sample area in the frame, block off any gaps where water can run under the frame or the net. Use surrounding substrate materials. (In a stronger current you may have to hold the surber in place for sampling.)
5. Carefully turn over and hand-rub all the stones inside the frame to dislodge any organisms that may be clinging to them. Before discarding them, examine each one by eye. Sometimes insect larvae and pupae cling very tightly. Make sure everything gets caught in the sampler net.
6. Stir the remaining gravel and sand with your hands or sticks to a depth of 5 to 10 cm. This will dislodge bottom-dwelling organisms. Hand-pick snails and other “heavier” organisms that are not picked up by the current.
7. Keep an eye on the net. If it becomes too clogged, sample can be lost from backwash.
8. On shore, invert the net into a sample container or a sieve with the same or smaller mesh size. Rinse down the net. Carefully examine the net for clinging organisms. Remove with forceps.
9. Rinse down the sampler after each use. Let it dry completely before storage.
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