Fisheries Report for the Middle Stour 2012
Thirteen sites were fished using electric fishing gear between 25 th July and 18th September 2012.
Results are reported here using fish greater than (>) 99mm as electro-fishing has been shown to be inefficient below this band.
Seventeen species were identified during the survey and three hybrids types. 3408 fish (>99mm) were caught.
The average density (number of fish in a given area) of all species (>99mm) over all sites rose from 12.55 Ind./100m2 in 2009 to 18.39 Ind./100m2 in 2012, an increase of 47%.
Total average standing crop (weight of fish in a given area) also rose from 1788.35 g/100m2 in 2009 to 1855.30 g/100m2 in 2012, an increase of 4%. Standing Crop Composition (%)
Density Composition (%)
4%
9%
14%
30%
23% 18%
2%
Chub Dace European Eel Perch Pike Roach Other
7% 8% 45% 5%
2%
25% 8%
Density of fish species (>99mm) on the Middle Stour 12
Density (Ind./100m 2)
10
8
Chub Dace Eels
6
Perch Pike
4
Roach
2
0 1985
1988
1991
1994
1997
2000
2003
2006
2009
2012
Mean
Roach were the most common fish >99mm reaching 8 individuals for every 100m2 of the river surveyed, or a 45% share of the population (followed by dace with an 18% share each).
Roach numbers are showing a cyclic trend over time, rising and falling around the long term average. After a fall in numbers in 2003, roach numbers are increasing once again.
The densities of chub, dace, perch, pike and roach are all above their respective long term means.
Eels are the only species to have exhibited a drop in numbers from the long term mean. After peaking in 1988 at 1.2 Ind./100m2 eels have steadily declined to 0.4 Ind./100m 2 to date.
Smaller fish under 99mm are not included in these graphs as they are not accurately collected. Standing crop of fish species (>99mm) on the Middle Stour 900
Standing crop (g/100m2)
800 700 600
Chub Dace
500
Eels
400
Perch Pike
300
Roach
200 100 0 1985
1988
1991
1994
1997
2000
2003
2006
2009
2012
Mean
The standing crop figures recorded for chub, dace, perch, pike and roach in 2012 were all above their respective long term averages for the 28 year period spanning 1985 to 2012.
Eels are the only species to have recorded an overall decline in standing crop in the sampling period, with a fall of 80% since records began in 1985. This would indicate several of the larger yellow eels encountered on previous surveys have moved out of the system.
Although the density of chub comprises only 9% of the total density of fish in the Middle Stour, chub account for the greatest proportion of the standing crop with a 30% share.
Interestingly roach density increased by 22% between 2009 and 2012 but roach standing crop decreased by 8% over the same period. This indicates an increase in recruitment and survival of smaller fish beyond 2 years of age (>99mm) in the river.
The largest individual (mm) and species population estimate (>99mm) are recorded for chub, dace, perch, pike and roach at site level in the table below. CHUB Size (mm) Higham Hall Boxted Mill Tendring Hall Anchor Bridge Wiston Mill Wissington Wormingford Mill Bures Mill Bures Bridge Lamarsh FGS Pitmire Shalford Weir Mill Meadow
DACE
PERCH
PIKE
ROACH
No. 93 2 68 1 31
Largest 463 468 433 133 475
No. 146 3 258 35
Largest 211 146 236 237
No. 3 20 7 21 18 13
Largest 158 267 309 283 204 313
No. 3 14 15 9 11 3
Largest 626 560 646 610 533 564
No. 5 68 14 252 14 46
Largest 133 204 149 222 143 187
19
491
41
231
21
283
11
732
87
265
1 20 50 4 8
484 524 514 433 293
8 12 14 6
137 192 147 180
7 16 36 62 14 36
189 191 361 203 185 356
7 15 38 62 15 19
365 415 809 582 658 473
30 72 382 150 175 333
203 202 241 184 228 267
The largest fish from the surveys were:
a 524mm (4.0lb) chub at Lamarsh Flood Gauging Station.
a 237mm (0.4lb) dace at Wissington.
a 361mm (2.2lb) perch at Lamarsh Flood Gauging Station.
a 809mm (11.1lb) pike at Lamarsh Flood Gauging Station.
a 267mm (0.9lb) roach at Mill Meadow.
Before you go fishing don’t forget
You must have an Environment Agency rod licence before you fish and permission from the fishery owner. You must comply with the fisheries byelaws. The course fish close season (15th March – 15th June inclusive) applies to all rivers, streams and drains in England and Wales, but not to most stillwaters. Stillwater fishery owners can have their own close season and rules, so please check with them before setting out.
Reporting illegal fishing If you see any fishing, netting or trapping you think may be illegal, please don’t tackle it yourself. Call us on 0800 80 70 60 and tell us: Exactly where the alleged offence is taking place What’s happening How many people are involved and their descriptions The registration numbers of any vehicles involved.