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NB There was no result for July 2007 and high flows prevented sampling in November. I understand that monitoring is scheduled to re-start this month.
As can be seen from the results, all target groups were recorded apart from Ephemera Mayflies. Although they are known to be present in the Bela, at our routine site (N498), they have only been recorded once (a single specimen in December 1997) since 1990. As expected, Ephemerellidae (BWO's) were recorded at reasonable abundance May-August with a couple found in September and apparently absent in October.
Results are all well above the trigger level and apart from the October result have reached or surpassed the target level. The October result recorded 5 of the 8 target groups and the presence of Heptageniidae Mayflies at Abundance C (200 estimated) indicates no serious water quality problems.
As well as the natural variations discussed earlier, there are bound to be some operator differences, particularly with 4 pairs of anglers sampling on a rotation system. This should improve with experience and if more sites are set up on the catchment (as is planned) then ideally the same sampling pair could sample their own site exclusively. For interest however, some swapping of sites may be desirable.
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