June 03 Report for Hatchery

In May and June the Hatchery released 21,000 sea trout fry (average weight 1.0gm) to the upper reaches of the Afon Wnion. This is done each year at approximately the same time after these fish have been size graded. A further 36,000 sea trout and 5000 salmon are being reared at the Hatchery for release into the Mawddach catchment later in the year.

On the 19th of June 35,000 salmon fed fry were collected and released into the Thames catchment. This is part of the ongoing Thames rearing contract which the Hatchery is involved in.

During the month plans were finalised for the construction of a semi-natural rearing pond on the upper reaches of the Wnion. A suitable site was found and after talks with the landowner an agreement was reached to use a pond for rearing and release of sea trout and salmon into the Wnion. The pond will be constructed using the same design features as the Afon Eden pond, which has been a great success.

MAWDDACH HATCHERY JULY 2003 REPORT

Weather conditions.

During the month water temperatures continued to rise with the dry weather conditions. On the 16th the water temperature was recorded at 19.5’C in the evening. The Hatchery has an aeration system, which oxygenates the water at times of high temperature and runs throughout most nights in July and August. The optimum feeding temperature for salmonids is 12-14’C. When water temperatures rise above this, the amount of food given to the fish is reduced.

Restocking.

July has been a very busy month for the Hatchery. A total of 140,000 fish were on site at the beginning of the month. All these fish were size graded and sorted. During the month just over 45,000 of these fish were released back to their rivers of origin. 26,500 0+parr sea trout were stocked out to the Wnion (8,100), Eden (3,400), Bronaber pond (10,200) and Ty Gwyn (4,800). The Afon Lledr smolt-rearing pond received 7,000 sea trout fry, the Western Cleddau 6,000 sea trout 0+parr and the Seiont 8,000 salmon fry.

New Wnion smolt release pond.

Construction of the new Wnion smolt release pond began in July, and will be completed in early August (see photo). Once the pond is finished 5,000 salmon 0+parr will be put into the pond and reared on to smolt before their release in spring 2004.

sea trout stocking Bron Aber smolt pond	sea trout stocking Afon Ty Gwyn	Wnion smolt pond under construction
Sea trout ready to be stripped	Male being stripped of milt	Female ready to be stripped	Eggs being released	Eggs and milt being mixed
MAWDDACH HATCHERY AUGUST 2003 REPORT Water temperatures. Water temperatures remained high throughout the month. In the evening of the 8th the water temperature was recorded at 21.5’c, this being the highest ever recorded at the unit. Mortalities were kept to a minimum with the use of the aeration system, running 24 hours a day. By the end of the month water temperatures had stabilised and lowered to around 15’c which is about normal for this time of the year. Pump well refurbishment. During the month the pump well floor was renewed. Sixteen years of continuous water pumping meant that the concrete well floor had begun to break up which could have caused serious damage to the pumps and resulted in a system failure. Both submersible pumps and their pipework were removed so that a new floor could be laid (see photo). The work took nine days and was successful. Two submersible pumps were hired to pump the water into the tanks whilst the work was carried out. Fish grading and restocking. During the month just over 23,000 fish were stocked out from the unit; these included 4,000 salmon to the upper Lledr, 3,950 salmon to the Axe in Somerset, 6,000 salmon to the upper Conwy pond at Pentrefoelas and 9,500 fin clipped sea trout to the Western Cleddau. All the fish were size graded before release back to the river (see photo).

Grading	Pumps being renewed

MAWDDACH HATCHERY MONTHLY REPORT SETEMBER 2003

Throughout the month water temperatures continued to fall back to their normal for september (12’c to 14’c). All the fish were size graded during the month, which is always done each year at this time.

RESTOCKING

During the month the Afon Llugwy was stocked with 4000 sea trout parr weighing 8.5gms each. These were stocked directly into the river just above Betws y Coed. Next year it is hoped that these fish will go into a smolt release pond which is being constructed on the upper reaches of the Afon Llugwy. 4000 salmon parr were stocked into the Bronaber smolt pond for over-wintering before release next spring into the Afon Eden.

On the 10th of September 4900 sea trout parr were stocked into the newly constructed Wnion smolt release pond (see photos). These fish will be released into the Afon Wnion next spring.

MAWDDACH HATCHERY OCTOBER 03 REPORT.

Late September and early October are perhaps the quietist periods at the unit in the year. Hatchery staff tend to concentrate on routine maintenance work whilst preparing for the broodstock season to begin. All the electrical systems, including pumps, generators, alarms have had their annual check-up to ensure as far as possible everything continues to run smoothly. The remaining stocking out of fish has been completed for the this year with 1000 salmon going into the Afon Lledr pond, 3000 salmon going to the Eden pond and 3000 salmon going into the new Wnion pond. The total number of fish in these ponds now totals 17000(10000 in Bronaber and 7000 in the Wnion pond) During the month the Hatchery manager visited the staff on the Axe in Somerset to see the new salmon trap (see photos) that has been constructed for collecting broodstock this year(If we ever get any rain!!) October has been another dry month and at the time of writing water conditions are very low. All the fishery staff are standing by to collect the broodstock when the rain arrives. The sea trout trap on the Afon Las has been installed(see photo). It is interesting to note that in the sixteen years of this Hatchery being in operation we have never had to wait so long for any ova to be laid down. We shall be incubating ova for restocking schemes on the Mawddach,Wnion, Eden, Thames, Lledr, Llugwy, Seiont, Western Cleddau and Axe this year.

Afon Las trap	Afon Las trap detailed view	River Axe trap	River Axe trap - different view

MAWDDACH HATCHERY NOVEMBER REPORT 03

In the previous sixteen years of operation of this unit we have by the end of this month always laid down at least 100,000 ova. At the time of writing this report the number of ova laid down has not reached 50,000. By the time it began to rain in any quantity the month was nearly half over. The results for sea trout for the Mawddach catchment are very disappointing, with only 16,000 ova laid down this year (target figure 50,000). It is a mystery as to what has happened to all the sea trout that were seen in the lower reaches of the rivers in the late summer. It may be that these fish decided to spawn in the main river as they did not have the river flows to move up to the smaller streams.
Salmon are also in short supply, with the fisheries team struggling to find hardly any fish. Salmon do spawn slightly later than sea trout so there is still time for these to be caught.

On a much brighter note 20 salmon have been caught in the Lledr trap and brought into the Hatchery. Of these 20 fish no less than five were tagged fish originally from the semi-natural rearing pond on the Lledr (see photo adipose fin-clipped). This is very encouraging, and shows the benefit from this method of restocking. It was also noted that these five tagged fish were in almost perfect condition.

All the broodstock brought into the Hatchery are injected with a fast acting antibiotic which protects them against bacterial

semi-natural rearing pond on the Lledr	adipose fin-clipped broodstock	Injecting antibiotics

MAWDDACH HATCHERY DECEMBER 2003 REPORT

Broodstock collection continued throughout the month, with the Hatchery staff and Fisheries team working hard to find any available broodstock. Electrofishing on the upper reaches of the Eden(see photo) produced few fish, normally a productive area for broodstock. The fish trap on the Afon Las was checked for the last time on the 12th(see photo). Final numbers of ova laid down for each river catchment are listed below.

Mawddach salmon 20,600
Mawddach sea trout 18,460
Western Cleddau sea trout 13,700
Axe salmon 17,432
Llugwy sea trout 3,950
Conwy salmon 73,580
Seiont sea trout 13,420
Tal y Llyn brown trout 3,860

Hatchery flooding
On the 13th of the month after almost 24 hours continuous rain the Hatchery compound flooded at 7.00 am (see photo’s) The flood lasted for approximately three hours. There was no damage caused, the pumps continued to run and all the tanks and rearing troughs received their usual supply of fresh water.

Flood in hatchery - 13th December 2003	General view of flood	Trap on the Afon Las, Ganllwyd.	Electrofishing on the Afon Eden.

MAWDDACH HATCHERY MONTHLY REPORT JANUARY 2004.

The annual microtagging programme commenced with the batch tagging of 40,000 Shannon destined for the Thames in March (see photograph’s). This year the, during the tagging, hatchery staff were assisted for four weeks by Bangor University Student Patrick Mahon, who is studying Marine biology and Zoology.
In addition to microtagging the Thames fish, 8,000 Mawddach and Wnion fish which go to Dolmelynllyn pond and the Wnion pond have been fin-clipped, and 8,000 salmon, which are stocked into the Roman Bridge pond on the Lledr, and the Pentrefoelas pond on the upper Conwy have also been fin-clipped. These fish will all be stocked out to their respective sites in February.

On the 31st of the month 100,000 'eyed' salmon ova were delivered from the Parteen hatchery on the Shannon in Eire ( see photograph’s). These ova are delivered at approximately the same time each year and are used for the restoration of runs of salmon to the Thames.

All the ova stripped before Christmas continue to do well and most of the sea trout ova laid down have now hatched. The winter has once again been relatively mild so this advances

Shannon ova	Close up	Placing in trays to hatch	Sorting out
Fin clipping	Injecting parr	Overview of process	and again
MAWDDACH HATCHERY MONTHLY REPORT FEBRUARY 2004 During the start of the month the annual microtagging programme was completed for the Thames. The Thames smolts will be collected in early March for their journey by road before restocking into the Thames. All the other 1+parr and smolts reared this year have now been stocked out to their respective rivers, namely, salmon to the Lledr, Conwy, and Wnion smolt ponds and sea trout to the Mawddach smolt pond. The beginning of the month saw extremely high river levels after a prolonged spell of rain. The Hatchery compound was again flooded, and the flooding lasted for 12 hours on the 3rd and a further 9 hours on the 4th. These floods were the longest on record for the Hatchery site to be flooded, thankfully the tides were not big at the time, so there was no damage. Water temperatures have been have been above average for the month, February can be one of the coldest months of the year. These higher than average temperatures mean that hatching of the fry is brought forward, and by the end of the month all the ova in the incubation unit had hatched. The first Mawddach sea trout fry to hatch and consequently feed were transferred outside on the 24th of the month (see photo’s) . The 3.5metre tanks at the unit are stocked with approximately 20-25,000 fry each when they come out of the incubation unit.
Fry in trays	and again, general view	Fry being put out in outside tanks	close up
MAWDDACH HATCHERY MONTHLY REPORT MARCH 2004 Temperatures at the beginning of the month were very low (1.5’c) which slowed the development of the alevins for a number of days. As the month progressed, however, temperatures recovered to the mean of about 6.5’c for this time of year. On the 1st and 3rd of the month 35,000 S1 salmon smolts were collected for delivery to the Thames( see photo’s) By the end of the month all of the sea trout had been moved outside into either the 2 metre square fry tanks or 3.5 metre circular tanks. The majority of salmon were first fed towards the end of the month. The salmon are first fed in the incubation troughs for seven days then transferred outside to the large circulars. On the 11th of March a fuel oil spillage in Dolgellau polluted the Afon Wnion. At first there appeared to be no significant contamination of the water supply to the unit, however by Monday 15th of March there was an increase in mortality of the salmon fry, resulting in the loss of approximately 6-7000 Shannon fry. Investigations are being carried out, and the mortalities have now cleared. This could have had far more serious consequences for the unit, and one wonders what the damage to the ecology of the river may have been.
MAWDDACH HATCHERY MONTHLY REPORT APRIL 2004 Throughout the month fry from the incubation unit were gradually brought onto feed. To begin feeding, the fry are fed in the incubation troughs (see photo) using the clockwork feeders, and then they are moved outside to the large tanks to be fed (see photos). At the time of writing all fry are now feeding. The water temperatures for the month have been favourable for first feeding, as the fry feed best when water temperatures are above 8°C. On the 23rd of the month, both smolt release ponds were netted and emptied of all their fish so that they could make their journey to the sea(see photos).
MAWDDACH HATCHERY MONTHLY REPORT - May 2004 May is perhaps the busiest month of the year at the unit. The water temperatures usually rise above 8°C for a sustained period, this being vital to bring the fish onto feed successfully. The 200,000 fry presently held on site require almost constant attention, to ensure that they have an adequate supply of fresh water and have the correct amount of food. At this time of the year the fish can increase their bodyweight by as much as 10% per day, this means that constant adjustments to the amount of food being fed is required. At the end of the month the Shannon fry were given their first grade of the year (see photos). Grading ensures that mortalities are kept to a minimum, as the larger fish will attack the smaller ones if they are not separated. Increasing water temperatures can also encourage parasitic and bacterial infections of the skin and gills, so the fish are regularly given prophylactic treatments to guard against any infections. 9,000 Wnion salmon fry were stocked to the upper reaches of the Wnion on the 24th of the month and on the 25th 8600 Seiont sea trout fry were returned into the Seiont catchment.

MAWDDACH HATCHERY MONTHLY REPORT JUNE AND JULY 2004

First of all apologies to everyone who expected to see a June report before this. Due to unforeseen circumstances I was unable to write the June report earlier.

Maintenance.

Throughout the last two months Hatchery staff have been very busy, not only with the usual fish husbandry work, but also with some maintenance work. Two of the large circular tanks had to be temporarily taken out of use, as these tanks developed faults, which needed urgent repair (See photos). Both tanks had developed splits in their bases, which resulted in the tanks leaking, obviously making them temporarily unusable.

Installation of new tanks

Two new 2metre square holding tanks have been installed (see photo). These tanks will be used for grading, sorting and temporarily holding various batches of fish.

Restocking.

Throughout June and July over 53,000 fish have been stocked out to the following locations;
7,500 Wnion Sea trout 0+parr to the Wnion smolt pond, these were fin-clipped,
5,000 salmon fry to the Conwy tributaries,
25,000 salmon fry to upper Thames,
5,800 fin-clipped sea trout 0+parr back to the Western Cleddau (photos)
10,000 salmon fry to upper conwy smolt release pond.

MAWDDACH HATCHERY MONTHLY REPORT AUGUST 2004

August has been a very busy month at the unit with a large number of fish being graded, sorted and delivered to a number of locations. (see table below). For the first time over 10,000 salmon and sea trout were stocked into the new Afon Llugwy semi-natural rearing pond,(see photos) which is sited on the upper reaches of the Llugwy. These fish will be reared on overwinter until their release next spring as 1+parr and smolts.

Many of the fish released from the Hatchery are fin-clipped or tagged so that if one is caught the angler can notify the Agency staff. An example of a clipped fish can be seen in the attached photo. This was caught by Nigel Shaw in August on the Mawddach.

Aug-04
DATE SPECIES ORIGIN NUMBER WGHT BATCH STK TO
2.8 SALMON WNION 4000 3gms Afon Ty Gwyn
2.8 SALMON WNION 3816 3gms Wnion pond
6.8 SALMON MAW 5000 2.5gms Bronaber pond
6.8 SALMON CONWY 10188 2.5gms Llugwy pond
6.8 S.TROUT LLUGWY 1700 4.0gms Llugwy pond
12.8 S.TROUT MAW 3500 2gms Afon Eden
26.8 SALMON CONWY 10100 4gms Pentre pond
31.8 S.TROUT CLEDDAU 7200 5gms w.cleddau
45504

Mawddach hatchery monthly report September 2004

During the month remaining numbers of fish to be stocked out were graded, sorted and where necessary fin-clipped before release to their rivers of origin. 6,000 + parr salmon were finclipped before their collection and subsequent release into a purpose built semi-natural rearing pond on the river Axe in Somerset. A further 3000 salmon were released directly into the Otter and Culm rivers in the same region. A further 9500 salmon were released into the Pentrevoelas smolt pond on the Upper Conwy.

Sep-04
DATE SPECIES ORIGIN NUMBER WGHT BATCH STK TO
1.9 SALMON CONWY 9500 3gms pentre pond n.o.2
16.9 SALMON AXE 6000 8gms Clipped AXE POND
16.9 SALMON AXE 2000 3gms OTTER
16.9 SALMON AXE 1000 3gms CULM

At the end of the month the Hatchery has retained a total of nearly 60,000 salmon and sea trout for over-wintering before their tagging and release next spring.

Mawddach hatchery monthly report October 2004

As the broodstock collection season comes around again, preparations are well in hand to collect fish from the required rivers for all the schemes being undertaken this Autumn at Mawddach. The first fish to be collected, as in most years, are the Mawddach sea trout captured on the Afon Las. These fish were collected from the trap after the heavy rain on 22.10.04. The trap is cleaned most days during the autumn, (see photo), so that it functions properly.

On the 26th of October the Lledr trap was checked and a total of 13 salmon were collected from the trap. Of the thirteen 4 of these fish were tagged (see photo). These fish were returning up the Lledr towards their original release site above Dolwyddelan. This is a very good proportion of tagged salmon amongst the wild fish and demonstrates the value of stocking salmon into semi-natural smolt rearing ponds. This is the third consecutive year that a considerable proportion of fin-clipped salmon has been captured in this trap. As only a small proportion of the salmon run up the Lledr are being caught in the trap, it is likely that the restocking programme on the Lledr is now having a considerable impact on the numbers of returning fish.

Other schemes being undertaken at Mawddach Hatchery this autumn are listed below.

Mawddach catchment, (salmon and sea trout)
Axe (Somerset) salmon.
Western Cleddau (sea trout)
Llugwy (salmon and sea trout)
Tal y Llyn (Brown Trout)
Seiont (salmon and sea trout)

At the time of writing this report it has not been confirmed that the contract to rear salmon for the Thames is going to continue, and this will be reported on next month.

Mawddach hatchery monthly report November 2004

During the month of November the bulk of the broodstock collection takes place (see photo of broodstock collection team for Gwynedd and Clwyd). This year difficulties in collection for some of the schemes have been encountered. In particular rearing programmes for sea trout have been restricted and in some cases cancelled due to the unavailability of any broodstock. There are two principal reasons for this; the general low numbers of sea trout in the rivers and the lack of rain at the crucial time of spawning has meant that sea trout collection has been extremely difficult. Only 25,000 sea trout ova for the Mawddach catchment have been laid down this year (the target figure was 50,000), and on the Western Cleddau no broodstock were collected, so the scheme has been shelved for this season. In contrast to the sea trout there appears to have been a greater number of salmon in the rivers this year, consequently most of the Hatchery rearing schemes for salmon are going ahead. To date 30,000 Mawddach salmon and 25,000 Lledr salmon ova have been laid down. Final numbers of ova laid down will be reported next month.

On the 16th and 17th of November the Hatchery manager visited Belfast to attend a freshwater pearl mussel workshop. The purpose of the workshop was to formulate a strategy to halt the decline of the mussel populations in the rivers of England, Wales, Ireland and Scotland. In some rivers the reduction in populations has been rapid, therefore urgent action is now required to reverse this trend. It is planned to initiate a captive-breeding programme to eventually reinstate populations.

Mawddach Hatchery monthly report December 2004

This year for the first time the annual microtagging project to tag 40,000 Thames fish was started in December instead of January. A total of 20,000 Thames fish have now been tagged with a further 20,000 scheduled to be tagged in February. With regard to the Thames rearing contract, it has been decided to cut the number of fish being reared from 40,000 to 20,000 per annum. This is largely as a result of budget costs in the Thames region. As a result only 50,000 ova are being purchased from the Shannon Hatchery in Ireland in January 2005.

The final numbers for ova laid down are as follows

Mawddach sea trout 27,000
Mawddach salmon 47,000
Lledr salmon 55,000
Llugwy salmon 16,000
Seoint salmon 5,000
Tal y Llyn Brown trout 5000

Considering the difficulties experienced in obtaining broodstock this year, these numbers were good. On the Axe in Somerset and the Western Cleddau, no broodstock were collected this year. These schemes will be carried on in 2005 assuming the broodstock can be collected.

MAWDDACH HATCHERY MONTHLY REPORT January 2005.

Throughout the month weather conditions have been favourable except for the 7th when persistent heavy rain resulted in the hatchery compound flooding. There was no damage in terms of equipment and mortalities of ova, fry and smolts were normal for this time of year. A very mild month meant that incubation times were accelerated. The first sea trout hatched on the 27th December and the first salmon on 27th January. The earliest sea trout to hatch are now being first fed.

At the end of December it was decided that the Thames contract to rear 35000 fry and 40000 smolts is going to be reduced by 50%. This is a result of budget costs in the Thames region. This is a disappointing situation as the Hatchery has been producing these fish for a number of years. This means that instead of the usual delivery of 100,000 ova from Eire there will only be 50,000 delivered this year.

Towards the end of the month the annual microtagging of the 40,000 smolts was concluded. These fish will be collected in early March for restocking into the Thames.
At present the unit is holding 60,000 smoltas for delivery to the Thames, Mawddach and Lledr rivers in February and March.

Mawddach Hatchery monthly report February 2005.

On the 10th of the month the annual microtagging programme was completed. This year just over 40,000 salmon have been tagged (see photos). These will be collected in March. The mean weight for these fish will be considerably higher than in previous years, and should be in the region of 45gms average.

Throughout the month the ova continued to hatch in different stages. Over the last two years the Hatchery has been trialling a new method of incubating the fry. The alevins are transferred outside to a deep substrate tank (see photo). The fry have shown good results in the last two years in terms of survival, so this method is being extended this year (see photos). In the previous two years the results have very encouraging with much lower mortalities than fry reared in the traditional way.

Mawddach Hatchery Monthly report-March 2005

At the beginning of the month the 40,000 microtagged salmon smolts were collected for the Thames restocking project, (see photos). As in previous years, these were collected by George Baird from Scotland.

It was pleasing to see that this years smolts had the largest mean weights of just over 45gms, and were in excellent condition when they left the Hatchery.

Throughout the rest of the month this years alevin and fry were gradually bought onto starter feed (see photos). Although the first fry were transferred to outside tanks in February the majority of fry are transferred outside in March and April when water temperatures have begun to increase. Production of wild salmonids is a very difficult business, as the quality of the progeny from the recaptured wild broodstock can be highly variable. Every year there are ova, alevins and fry that struggle to survive. In the end decisions sometimes have to be made to sacrifice certain batches of fry as they run the risk of increased mortality through secondary infection caused by their poor initial condition. This year approximately 30000 ova and fry have shown unidentfiable problems and these fish have been sacrificed.

On a much brighter note there are approximately 40,000 salmon and asea trout parr and smolts in 5 smolt release ponds in North Wales. These are in the process of smolting and will be released in April.

MAWDDACH HATCHERY MONTHLY REPORT APRIL 2005

On the 25th of the month the remaining 60,000 early feeding fry were transferred out of the incubation unit into outside tanks. Once they have had seven days feeding inside the incubation unit the fry are assessed for quality and a decision is then made as to where they will be put in outside tanks. The majority of fry continue to do well although the water temperatures in the early part of the month were disappointingly low causing some mortalities due to non feeding fry.

On the 28th of the month 5000 salmon fry originating from broodstock captured on the upper reaches of the Wnion were released into the Wnion just outside the Hatchery. This area of the river has very good gravel substrate conditions which are particularly favourable to early feeding fry, as there is a good supply of food in this area. (see photos).

Mawddach Hatchery monthly report May 2005

General
Throughout the month all fishstocks were carefully monitored as the water temperatures remained low for this time of year. A mean daily water temperature of just 9.1?C was recorded for the month, which is one of the lowest ever recorded for the month. May is a critical month for the fish when they tend to start to feed in earnest on artificial food. Greater numbers of surviving fish will usually be achieved if the mean water temperature for May exceeds 10?C.

Freshwater pearl Mussel (margaritifera margaritifera)

During the month the hatchery staff began work on making and installing some tanks for the Fresh water pearl mussel (FWPM) project which is soon to begin at Mawddach hatchery (see photos). Three tanks have been installed so that some FWPM from three different rivers can be placed in separate rearing facilities at Mawddach Hatchery. Wild populations of these FWPM are becoming extremely low with apparently little or no recruitment of juveniles occurring in the wild; therefore it has been decided that a captive-breeding programme should be initiated. Progress of this project will be reported on in future reports.

Stock numbers

Numbers of fish held on site as at 31st of May are as follows;

River Axe salmon 1+parr 5,200
Afon Mawddach salmon fed fry 18,000
Afon Mawddach sea trout fed fry 10,900
Afon Llugwy salmon fed fry 3,200
River Thames salmon fed fry 43,000
Afon lledr salmon fed fry 31,000
Afon Seiont salmon fed fry 4,300
Tal y Llyn Brown trout fed fry 2,600

Mawddach hatchery monthly report June 2005.

The beginning of June saw staff changes and a reorganisation of the management at Mawddach Hatchery. The manager at Mawddach Hatchery is now also the manager of the Environment Agency Wales salmon Hatchery at Maerdy near Corwen. As a result of this Patrick Mahon, who has done some temporary work at Mawddach before, has joined the fish culture team to work at Mawddach Hatchery on a permanent basis.

On the 15th of the month the old river screen intake chamber was removed and a new one installed. The old chamber was beginning corrode and there was a possibility that during a flood large amounts of debris would get into the hatchery water supply.

On the 17th of the month the Shannon salmon were graded for the first time this year to enable 15,000 small salmon to be separated for delivery to the Thames on the 23rd of June.

Mawddach Hatchery monthly report July 2005

During the first part of the month very warm weather resulted in relatively high water temperatures, on one occasion the water temperature reached 20°C. The hatchery aeration system was run continuously during this period of high temperatures.

Towards the end of the month two of the three metre rearing tanks had to be emptied of fish and taken out of service so that stronger foundations could be put down for these tanks (see photos). The work took 5 days to complete, with a total of 7 tons of hardcore being put down as foundations for these tanks.

The following restocking of fish took place during the month;

4000 salmon, fed fry, Afon Wen (upper Mawddach)
4500 salmon, fed fry, Afon Seiont tributary.
7000 salmon, fed fry, upper Lledr.