Argulus egg collection update to end May 2023.
Norfolk Flyfishers Club lake, Swanton Morley, Norfolk.
Sixteen pipes for egg collection were put over the posts in the lake on 30th March and one more (pipe 4) added on 4th April. Water temperature at that time was 10°C when argulus were expected to begin laying. Three inspections and eggs removed have been carried out.
| Date | Approximate No. strings | Approximate No. eggs | Water temp °C | Water Clarity cms. |
| 26th April | 740 | 29,500 | 12.5 | 120 |
| 14th May | 625 | 36,200 | 14.8 | 300 |
| 30th May | 179 | 9,600 | 16.7 | 300+ |
| Totals | 1,544 | 75,300 |
Water temperature is measured by first platform on south bank below haul road. Significant numbers of caddis larvae were found on the pipes yesterday. These do predate on the argulus eggs. Large numbers of snails eggs are amongst others on the pipes.
Dennis Willis 1st June 2023