River Lossie Juvenile Fish Survey 2016
R. Laughton
FNL Fisheries Trust Report No. 2017-03
Findhorn, Nairn and Lossie Fisheries Trust,
Logie Steading, Forres, Morayshire, IV36 2QN.
Tel 01309 611220, Mob 07887 535986
Email [email protected]
Web: www.fnlft.org.uk
Prepared for
Lossie District Salmon Fisheries Board
July 2017
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River Lossie Juvenile Fish Survey 2016
R. Laughton
FNL Fisheries Trust Report No. 2017-03.
Findhorn, Nairn and Lossie Fisheries Trust, Logie Steading, Dunphail, Forres, Morayshire, IV36 2QN. Tel 01309 611220, Mob 07887 535986, Email [email protected], Web: www.fnlft.org.uk
1.0 Introduction
The River Lossie is situated in Morayshire, north-east Scotland and lies between the Spey to the East and the Findhorn to the west and flows for approximately 45km from Loch Trevie to Lossiemouth on the Moray Firth coast. The river supports a fishery for both salmon and sea trout with the latter viewed as the more important fish.
The middle and lower reaches the land use is dominated by arable farming while in the upper reaches, from Dallas to the source at Loch Trevie the land-use includes both arable and livestock farming, moorland and commercial and semi-natural forest. There is also significant quarrying activities along the river near Cloddach. Additional developments include the Rothes wind farm in the upper reaches and the Berry Burn wind farm also impinges on a small part of the upper Lossie. The main urban areas are Elgin and Lossiemouth and both create potential for increased pollution to enter the watercourse.
There are several distilleries within its catchment area, which in general adhere to strict guidelines regarding water uptake and discharge. Distilleries require large quantities of cold water for the distillation process. After use this cooling water is usually released back into the nearby burn and can often raise the water temperatures above normal which in turn can affect juvenile fish growth although this may not affect the returning adults (Laughton and Laburn, 2001). In addition weirs are often installed to extract the water which can restrict fish passage which is particularly evident on the Linkwood Burn where several impassable weirs are currently present.
Early juvenile fish data for the Lossie is available from a limited electro-fishing survey of fish populations at four locations in 1987 conducted by the Freshwater Fisheries Laboratory (now Marine Science Scotland, MSS) in Pitlochry. A more comprehensive survey of fish populations within the Lossie was completed in 2000 by McRitchie and Laughton (2000) and a further survey of two sites on the main stem Lossie near Mayne Farm was completed in
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2002 (Laughton and Burns, 2003). Further fish data is also available from surveys commissioned by the Moray Flood Alleviation scheme during the last few years (Aquaterra Ecology 2009a-d, Era 2004, Era 2006a-b).
The River Lossie Fisheries Management Plan (Laughton, 2010a) highlighted the need for better data on fish populations (FMP Action 3.1), leading to a further surveys in 2010 and 2013 (Laughton, 2010b; Aspden, 2013). This survey repeats the majority of the survey sites examined in 2013 and aims to provide distribution and abundance data on the juvenile fish species present within the Lossie and its tributaries.
2.0 Materials and Methods
Electro-fishing was carried out using methodology prescribed by the Scottish Fisheries Co- ordination Centre (SFCC, 2007). Each site was approximately 100m2 and marked out using ropes at either end and as far as possible each site contained a range of fish habitats. Electro- fishing commenced from the downstream end, to and fro across the stream, until the full site area was fished.
The species present and fork length (tip of nose to the V of the tail) was recorded along with a small sample of scales for age determination. During 2016 each site was fished two times to provide population estimate data, with and fish captured retained between each fishing. After analysis all fish were returned to the site.
Details of the habitat available within the site including, water depth, flow type, substrate type, riparian vegetation, land-use etc., were also recorded along with a photographic record of the upstream and downstream limits and the general site surroundings. This also allowed re-orientation to sites from previous survey sites.
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3.0 Results
Table 1 and Figures 1 - 2 provide the locations of the sites electro-fished in the River Lossie and its tributaries during 2016.
Table1: Electrofishing site locations for the Lossie juvenile fish survey 2016. Date Site Fished Code Easting Northing Alt (m) River Location Main stem 200m downstream from 29/09/16 L1 325400 863850 5 Lossie Calcots Bridge 30/09/16 LMFU 320546 860514 25 Lossie Mayne Farm Upper Site 26/09/16 L2 320200 858450 45 Lossie 100m Above Cloddach Bridge 200m downstream of Kellas 28/09/16 L8 316606 853755 130 Lossie Ford 28/09/16 L9 314399 852908 140 Lossie 200m up from bridge at Park Downstream of Bridge at 30/08/16 L3 312650 852600 155 Lossie Torcastle Downstream of Bridge at 26/09/16 L4 312650 852600 210 Lossie Ballacraggan Below bridge above 28/09/16 L5 312400 847050 260 Lossie Torwhinny Falls Tributaries Linkwood 23/09/16 LW1 323500 861450 17 Burn Below Linkwood Distillery Linkwood Upstream from Linkwood 23/09/16 LW2 322600 860950 22 Burn Distillery Weir Linkwood Below Blossom Bank House 31/08/16 LW3 322400 859600 35 Burn Bridge Upstream of Miltonduff 30/09/16 LB1 318200 860100 30 Black Burn Distillery Downstream from Road 30/09/16 LB2 313150 857100 70 Black Burn Bridge 05/10/16 LB5 309342 854205 25 Black Burn Below Valeries House Gedloch 29/09/16 LS1 320750 855300 110 Burn Below waterfall Downstream of Bridge at 26/09/16 LCB 314050 849650 200 Corrhatnich Aultahurn Auchness Downstream from Road 26/09/16 LA1 314050 849050 205 Burn Bridge Clashgour 28/09/16 LC1 312100 846750 275 Burn Below Drainage Pipe Auchness 30/08/16 LAu1 311900 849750 175 Burn Below Double Culvert Lhanbryde 30/09/16 LH4 327300 860300 40 Burn Scotsburn Farm
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Figure 1: Electrofishing site locations on the lower River Lossie 2016.
Figure 2: Electrofishing site locations on the upper River Lossie 2016.
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3.1 River Lossie Main Stem Sites
Table 2: Densities of trout and salmon by age class and the numbers of other fish species captured at main stem Lossie electro-fishing sites during 2016. Note sites are arranged in ascending altitude the lower to the upper Lossie. 2016 Salmon (m-2) Trout (m-2) Other Species Salmon Salmon Salmon Trout Trout Trout Trout Site 0+ 1+ 2+ 0+ 1+ 2+ 3+ L1 0.09 0.04 0.00 0.00 0.00 0.00 0.00 Stk=6, M=4, F=20, E=6, L=1 LMFU 0.62 0.03 0.00 0.09 0.01 0.00 0.00
L2 0.38 0.11 0.00 0.13 0.13 0.13 0.00
L8 0.67 0.14 0.00 0.00 0.00 0.00 0.00
L09 1.54 0.23 0.00 0.00 0.00 0.00 0.00
L3 0.59 0.02 0.01 0.00 0.00 0.00 0.00
L4 0.00 0.03 0.00 0.32 0.05 0.00 0.00
L5 0.00 0.00 0.00 0.14 0.89 0.07 0.01
E=Eel F=Flounder L=Lamprey M=Minnow Stk=Stickleback(3 spined)
Salmon
Table 2 provides the density data for salmon and trout at the main stem survey sites along the Lossie during 2016. With the exception of L5, salmon were present throughout the Lossie main stem with the highest density of salmon 0+ (1.54m-2) and 1+ salmon (0.23m-2) at site L9 near Park Bridge, Dallas Estate, some older 2+ salmon parr (0.01m- 2) were also present at site L3, near Torcastle Bridge Dallas Estate. Salmon were absent at site L5 which is above Torwinny Falls and impassable to adults.
In the Lossie tributaries (Table 3) 0+ are present at three sites fished, LB1 on the Black Burn, LCB on the Corrhatnich Burn and at LAu1 on the Auchness Burn. Older 1+ salmon were also present in these three burns and in addition were found in at site LW1 in the lower Linkwood Burn and for the first time in the Yellowbog Burn, site LA1. In general the juvenile salmon were found at the lower sites, close to the main stem, and densities of each age class were low.
Salmon were absent above the weir on the Linkwood Burn at site LW12 and LW3 and additional surveys by SEPA during 2016 indicated that trout were only present above
6 this weir (data supplied by SEPA). Salmon were also absent in the upper sites of the Black Burn LB2 and LB5. Surveys in 2013 indicated salmon had spawned near LB2 after the gabion baskets had been removed but no salmon were found during this survey. The upper site LB5 is more favourable to trout with salmon unlikely to establish here.
For the other three tributaries, salmon were again absent from the lower Gedloch, (LS1) similar to previous surveys. There are no access issue to this site for adult salmon although an impassable waterfall is present a short distance upstream. Habitat would tend to favour trout with the burn narrow with good vegetation cover along the banks. Salmon were absent from the Lhanbryde burn (LH4) similar to previous surveys. Access for adults may be an issue further downstream with the lower reaches of this burn canalised and habitat also favours trout. The Clashgour Burn site (LC1) is above the falls at Torwinny which are impassable to adult salmon.
Trout
Table 2 indicates that trout were found at four of the eight sites electrofished along the main stem and densities at these sites ranged from 0.09m-2 to 0.32m-2, the highest density was recorded at L4 just below Torwinny Falls. Trout 1+ were found at four sites with densities ranging from 0.01m-1 to 0.89 m-1 at the upper site L5 above Torwinny Falls. A few 2+ and 3+ were also found.
Table 3 indicates that trout 0+ and 1+ were found at all the tributary sites fished in 2016 with 0+ densities ranging from 0.01m-2 at LA1 on the Auchness Burn to 0.50m-2 at LB5 on the upper Black Burn. Densities of trout 1+ ranging from 0.05m-2 at LS1 on the Gedloch Burn to 0.52m- 2 at LW3 on the Linkwood Burn. Older 2+ and 3+ trout were also found at several sites.
Other Fish
Main stem site L1 downstream from Calcots Bridge (Table 2) yielded a variety of fish species with flounders (20), eels (6), lamprey (1), minnow (4), and three-spined stickleback (6) all present. Other species were absent from the other main stem sites.
Table 3 indicates that within the tributaries, eels were caught at four sites, lampreys at two and sticklebacks at one.
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3.2 Tributaries of the River Lossie
Table 3: Densities of trout and salmon by age class and the numbers of other fish species captured at Lossie tributary electro-fishing sites during 2016. 2016 Salmon m-2 Trout m-2 Other Species Salmon Salmon Salmon Trout Trout Trout Trout Site 0+ 1+ 2+ 0+ 1+ 2+ 3+ LB1 0.05 0.19 0.00 0.21 0.12 0.03 0.00 E=1 L=1
LB2 0.00 0.00 0.00 0.33 0.09 0.03 0.00
LB5 0.00 0.00 0.00 0.50 0.43 0.07 0.00 E=2
LW1 0.00 0.10 0.00 0.37 0.17 0.00 0.00
LW2 0.00 0.00 0.00 0.32 0.23 0.03 0.00
LW3 0.00 0.00 0.00 0.40 0.52 0.05 0.00
LS1 0.00 0.00 0.00 0.44 0.05 0.02 0.00
LA1 0.00 0.03 0.00 0.01 0.12 0.06 0.06
LCB 0.01 0.02 0.00 0.09 0.18 0.03 0.00 L=1
LAU1 0.03 0.03 0.00 0.09 0.09 0.02 0.00 E=1
LC1 0.00 0.00 0.00 0.16 0.27 0.03 0.00
LH4 0.00 0.00 0.00 0.39 0.29 0.00 0.00 E=1 Stk=11
E=Eel L=Lamprey Stk=Stickleback(3 spined)
3.3 Juvenile Salmon and Trout Comparison with previous survey data.
The mean density of juvenile salmon and trout within the main stem and the tributaries was calculated for the 2016 survey and compared with similar data from previous surveys carried out in 2000, 2010 and 2013. As far as possible similar sites were utilised to calculate the means and for the tributaries only data from the areas accessible to adult salmon were used. Figure 3 and 6 show density comparisons for juvenile salmon and trout in the main stem and tributary sites.
Figure 3 indicates the results for salmon are encouraging within the main stem with both salmon 0+ and salmon 1+ increasing in mean density in 2016 when compared with the previous survey years. Figure 4 indicates a lower mean density in 2016 for trout 0+ but for older trout the mean density is higher than in previous years.
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Figure 5 indicates that mean density of salmon 0+ had dropped in the tributaries while there was an improvement in the mean density of older salmon. Figure 6 indicates that mean density of trout 0+ was similar to 2013 and higher than the two previous surveys in 2000 and 2010, while older trout densities continued to improve.
-2 Figure 3: Lossie mainstem salmon mean densities (m ) 2000 in 2000, 2010, 2013 and 2016. 2010 0.60 2013
0.50 2016
)
2 - 0.40
0.30
Density (m Density 0.20
0.10
0.00 Salmon 0+ Salmon 1+
Figure 4: Lossie mainstem trout mean densities (m-2) in 2000 2000, 2010, 2013 and 2016. 2010 0.30 2013
2016
) 2
- 0.20
Density (m Density 0.10
0.00 Trout 0+ Trout 1++
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Figure 5: Lossie tributary salmon mean densities (m-2) in 2000 2000, 2010, 2013 and, 2016 2010 0.30 2013
2016
) 2
- 0.20
Density (m Density 0.10
0.00 Salmon 0+ Salmon 1+
Figure 6: Lossie tributary trout mean densities (m-2) in 2000 2000, 2010, 2013 and 2016. 2010 0.30 2013
2016
) 2
- 0.20
Density (m Density 0.10
0.00 Trout 0+ Trout 1++
3.5.3 Classification of Survey Sites 2016
Using data from depletion electrofishing allows the density data to be compared with wider Scottish salmon and trout density data. Godfrey (2005) provides a classification range for juvenile salmon and trout populations based on a wide range of Scottish electrofishing data (Table 4). A comparison of the age class densities from the Lossie main stem and tributaries against this national classification range is presented in Table 5 and this gives an indication of the condition of juvenile densities within the river. The mean density data for salmon and trout 0+ and 1++ (1+ and 2+ age classes combined) is used here to illustrate the approach. This data is then compared with density ranges in in Table 4.
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In 2016 the main stem Lossie scored well for salmon 0+ and salmon 1++ with mean densities fitting into grade B and C respectively (Table 5). For juvenile trout within the main stem the equivalent grade were lower with trout 0+ in grade “C” and older trout in grade “E” (Table 5).
For the tributaries Table 5 provides a different trend with salmon 0+ in the low grade E and older 1++ salmon only reaching grade C. However, trout 0+ climbed to grade B and older trout were in the highest grade A.
In general the results indicate the main stem is supporting a good range of juvenile salmon while the tributaries are supporting higher levels of juvenile trout.
Table 4: National classification quintile ranges for juvenile salmonid density from rivers throughout Scotland. (Godfrey 2005) SFCC National Classification (Table 23) from Godfrey 2005
Category Salmon 0+ Salmon 1++ Trout 0+ Trout 1++
None N 0 0 0 0
Min E 0.002 0.003 0.002 0.002
20th percentile D 0.047 0.026 0.025 0.016
40th percentile C 0.103 0.051 0.053 0.031
60th percentile B 0.203 0.091 0.124 0.056
80th percentile A 0.421 0.158 0.303 0.104
Table 5: River Lossie mean densities and grades from National Classification Mean Density Salmon 0+ Salmon 1++ Trout 0+ Trout 1++ Main stem 0.56 0.09 0.09 0.16 Grade A B C B
Tributaries 0.01 0.05 0.28 0.25 Grade E C B A
4. Discussion
The 2016 electrofishing survey provided additional data on the distribution of salmon, trout and other species of fish within the River Lossie. It also allowed comparison with the similar
11 surveys completed in 2000, 2010 and 2013 (McRitchie and Laughton 2001, Laughton 2010b, Aspden 2013). In addition this season’s survey was modified to develop a set of core monitoring sites throughout the Lossie which were examined using a two fishing runs depletion methodology (SFCC 2008) this provides a more statistically robust data set which can be used to monitor change in population more readily and also in the longer term provide estimates of smolt output. Future surveys will concentrate on these core sites.
The 2016 survey showed an encouraging increase in mean densities of older trout in both the main stem and tributaries when compared to previous surveys. Trout 0+ densities were also good in the tributaries comparing favourably with previous surveys but densities of trout 0+ in the main stem had dropped in this survey year.
The main indications from this survey and the Torwinny falls upper Lossie. previous ones are that juvenile trout are present throughout the Lossie catchment. Densities are generally lower in the main stem but higher in most of the tributaries. Many of the tributaries such as the Linkwood, Blackburn, and Corrhatnich etc. contain relatively good stocks of trout fry and older trout parr indicating that they are important areas for sea trout and brown spawning. Above the waterfall at Torwinny good densities of trout were also determined and recent work on trout isotope (Briers and Reid 2015) has confirmed that sea trout do ascend these falls and contribute to the good densities observed.
Previous surveys of juvenile salmon indicate they are more restricted in their distribution with the main stem from Dallas downstream to the mouth providing the best densities (Aquaterra Ecology 2009a, Era 2006a-b, Laughton and Burns 2002, McRitchie and Laughton 2001, Laughton 2010b, Aspden 2013). The current survey also showed this and both salmon 0+ and 1+ showed improved mean densities than the previous surveys.
Juvenile salmon were less well distributed in the tributaries and although older salmon densities were improved slightly on previous surveys salmon fry densities were much lower.
Juvenile densities can vary considerably along the length of a tributary and even adjoining electro-fishing sites can have considerable differences in fish density (Amiro, 1990) as well as vary from year to year. This is clearly evident within the Lossie surveys with wide variations in
12 salmon and trout densities from site to site. Variations arise from many factors, both natural and man-made. Natural factors including ease of adult access, the availability of suitable habitat for spawning and juvenile development, and the presence of good riparian bank flora and fauna.
Many of the upper burns had good riparian vegetation and undercut banks were often present offering good habitat for juvenile trout generally accounting for the higher densities of trout observed in the tributary sites.
Juvenile salmon prefer faster flowing riffle areas and wider more open streams in their juvenile stages and although the gradient of main stem Lossie is fairly low some of this type of habitat is available supporting good densities of juvenile salmon. However, given that the general low gradient of the Lossie leads to a limited amount of suitable run/riffle type habitat, this may in turn limit the production of juvenile salmon.
A number of obstructions that affect fish passage have been identified throughout the Lossie, waterfalls are present on the Lossie at Torwinny, on the Gedloch Burn and on the Auchness Burn and weirs are present within Elgin and along the Linkwood Burn.
The Linkwood Burn is affected by several weirs and their removal or any remedial action to improve fish access would be beneficial to both salmonids and other species such as eels and lamprey. Discussions with the distillers and SEPA are progressing and tentative plans for installation of fish passes on some of the weirs are being developed to improve the Linkwood distillery weir. overall status of the burn.
The removal of the gabion weirs on the Black Burn in 2012 may have influenced the fish populations in the upper part of the burn. Salmon 0+ have been found at LB2 and LB3 in 2013 indicating that some adult salmon had progressed further upstream to utilise new spawning areas but no salmon were present during this survey. Trout 0+ densities had continued to improve and older trout densities were also good.
The current survey added to the previous data sets for juvenile fish within the Lossie and indicated positive trends in overall density for both salmon and trout. This was encouraging given recent downward trends in adult salmon and trout catches.
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6. Acknowledgements
I am very grateful to Haden Beck, Scott Galbraith and Fraser Laughton for their assistance with the electrofishing survey and to Alastair Skinner for data compilation. I am also grateful to Anthony Watkins and Ruth Watts from SEPA for suppling data on the Linkwood Burn. Thanks also to Rob Briers (Napier University) for completing the isotope analysis on the trout fry.
I am also grateful to all the estate proprietors, farmers and other individuals who allowed access to the survey sites and showed considerable interest in the survey findings.
7. References
Amiro, P.G. 1990. Variation in juvenile Atlantic salmon population densities between consecutive enclosed sections of streams. In: Cowx, I.G. (ed). Developments in Electric Fishing. Fishing News Books. 96-101.
Aquaterra Ecology 2009a. Elgin Ecological Surveys: Salmonid Fish. Report to Moray Flood Alleviation. February 2009.
Aquaterra Ecology 2009b. Elgin Ecological Surveys: Lampreys. Report to Moray Flood Alleviation. February 2009.
Aquaterra Ecology 2009c. Linkwood Burn Ecological Surveys: Salmonid Fish. Report to Moray Flood Alleviation. February 2009.
Aquaterra Ecology 2009d. Linkwood Burn Ecological Surveys: Lampreys. Report to Moray Flood Alleviation. February 2009.
Aspden, T. 2013. River Lossie Juvenile Fish Survey 2013. FNL Fisheries Trust Report No. 2013-05
Briers, R and Reid, I. 2015. Stable isotope analysis of trout fry from sites within the River Lossie system. Napier University Report. http://www.fnlft.org.uk/wp- content/uploads/2014/01/2015-Lossie_stable_isotope_report.pdf
Era. 2004. National Survey of Lamprey Phase I Report: Distribution in Scotland and survey of waters with records of lamprey. Report to Scottish Natural Heritage.
Era. 2006a. Elgin upstream ecological surveys: salmonid fish. Report to Moray Flood Alleviation. December 2006.
Era. 2006b. Elgin downstream ecological surveys: salmonid fish. Report to Moray Flood Alleviation. December 2006.
Era. 2006c. Linkwood Burn ecological surveys: salmonid fish. Report to Moray Flood Alleviation. December 2006.
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Laughton, R. 2010a. River Lossie Fisheries Management Plan 2010 – 2015. Spey Foundation Report 01/10. http://www.fnlft.org.uk/wp-content/uploads/2012/01/Lossie- Fisheries-Management-Plan-June-2010.pdf
Laughton, R. 2010b. River Lossie Juvenile Fish Survey 2010. Spey Foundation Report No 02/11
Laughton, R. and Burns, S. 2003. Juvenile salmon and Trout Populations at two Sites on the Lower Main stem River Lossie, 2002. Spey Research Report 01/2003.
Laughton, R. and Laburn, C. 2001. The Effect of Distillery Cooling Water Discharge on Adult Salmon Run Time in the River Fiddich. Spey Research Report 03/2001.
McRitchie, P. and Laughton, R. 2001. River Lossie Juvenile Survey 2000. Spey Research Report, No 02/2001.
SFCC. 1998. A Guide to the SFCC Electrofishing Protocol. (ed Puhr, C.) Scottish Fisheries Co-ordination Centre, Pitlochry. 19pp.
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