THE TWEED FOUNDATION

RUNNING TOTALS FOR THE ETTRICK FISH COUNTER, PHILIPHAUGH

  NET UPSTREAM FOR FISH OVER 40cms

NOTE : These are unprocessed figures and will change slightly on complete analysis 

YEAR 1998 19991 2000 20012 2002 2003 2004 2005 2006 Average 1998-20044 January 0 0 23 0 12 -1 0 0 43 4 February 0 -1 2 0 0 0 0 0 3 0 March 4 0 6 0 10 0 7 14 0 5 April 21 59 69 11 35 34 20 17 N/A 33 May 63 186 74 24 438 304 96 2026 236 401 June 360 224 401 11 335 Na 105 1636 127 439 July 173 47 60 75 115 155 170 31 170 103 August 426 20 557 425 432 71 670 124 35 341 September 1192 2401 2576 1045 940 94 1819 1561 2629 1454 October 2971 3357 2093 4039 1674 1858 2080 4242 2926 2789 November 1114 1310 579 531 1908 3201 412 567 845 1203 December 55 50 17 86 44 31 11 415   89 YEAR TOT 6379 7653 6457 6247 5943 (5747)3 5390 7337   6487 Year Salmon 3385 4701 4379 3801 4280 (3616)3 3602 4371   4025                       Totals to end:                     June 448 468 575 46 830 na 398 3966   452 July 621 515 635 121 945   568 427   547 August 1047 535 1192 546 1377   1238 551   927 September 2239 2936 3768 1591 2317   2887 2112   2550 October 5210 6293 5861 5630 3991   4967 6354   5472 November 6324 7603 6440 6161 5899   5379 6922   6390

(1) 1999 -The counter was out of operation for the second half of July and the first half of August but the water was then very low

(2) The Spring of 2001 was cold and then very dry, so there were no spates in the first half of the year to bring the fish up

(3) 2003 - An electrical storm on the 30^th of May put the counter out of action. There was a substantial run of fish on the 31^st which was uncounted. The monthly total for May is correct to the 6^th, then is an estimate from then to the 29^th when it was last manually read. The estimate given for May 2003 does not include any element for the 29^th to the 31^st of May . The counter was re-installed on the 4^th July, so the July total is for only 27 days

(4) Data from 2003 is not used to calculate the monthly averages for May, June and July or for the annual figures

(5)(1) A log in the scanner in June 2004 could not be removed till after the spate that had brought it down had passed
  (2) After the counter was switched off on the 19^th August 2004 to protect it from an electrical storm, it failed to re-start properly on the 20^th and was not corrected till the 23^rd. As the counts in the three days before were 41,41 & 22 and the counts in the three days afterwards were 37,42 & 30, reasonably consistent totals, it seems justifiable to average these for the missing two days’ counts, making 35 for each day to add to a total of 600 exactly for the other days of the month.

(6) The counter switched itself off on the 26^th May 2005 and was not restarted till the 2^nd June. (1)    The counts for the five full days before the switch off were 20,12,21,7 &11 respectively (daily average = 14), and 3, 17, 20,11 & 23  (daily average 15). Taking the average for a missing day as 14 therefore, 84 fish have been added to the May total, and 28 to the June (=112 extra for the total to the end of June)

Three video clips can be seen below, showing the passage of a small trout, a salmon during the night, and a slower than usual Salmon on which more detail can be seen.

http://www.tweedfoundation.org.uk/downloads/nightsalmon.avi

http://www.tweedfoundation.org.uk/downloads/browntrout.avi

http://www.tweedfoundation.org.uk/downloads/slowersalmon.avi

The camera which is installed in the counter films all the fish going up the Ettrick - follow this link to see the camera

2006 The counter was out of operation from April to the 16^th May, and for 24hrs on the 3^rd of July. A software problem became apparent in late September – although all fish were being “seen” by the computer, many were then rejected. The recorded total for September was 2501, revised total using data from visual counts for the days on which these were made was 2629. For other days in the month, no revision possible so the monthly total is very much a minimum – there were 2366 “rejects” recorded for this month. The October count is complete from the 10^th onwards, when the software was adjusted so that video clips were kept for each rejected

EFFICIENCIES : The counter is set count fish down to a minimum of 40cms in length. Some fish smaller than that do get counted, but with a low efficiency. The efficiency is checked by putting an underwater camera just upstream of the scanner so fish coming through can be seen and it can be noted whether they are registered by the counter or not.

Prior to its repairs in May 2003, the counter was 100% efficient for fish going Upstream and 88% efficient for fish going Downstream.  After repairs it is 97% efficient for Upstream and 97.3% for Downstream fish over 40cms.

NOT TO BE REPRODUCED OR PUBLISHED WITHOUT THE PERMISSION OF THE TWEED FOUNDATION

[Home] [About] [Management] [News] [Contact] [Site map] [Join]