The following major requirements were considered during selection of potential trout hatchery sites:
Water quantity and quality must be adequate at all times.
The slope of land must be sufficient to allow water to be drawn by gravity, via a pipe or canal to the fish farm, thus avoiding reliance on pumps.
Sufficient land area must be available and suitable for building.
Access to the land by road must be adequate (i.e., passable by truck at all seasons), and other services (power and telephone) be available nearby.
The river selected should have a history of seatrout runs.
Sites possessing all these attributes are not numerous, but several were identified. They are described below in order of preference, with reasons for their choice.
1. Çağlayan River. This river is believed to be the best for hatchery siting because it is large (with average flow rates close to those of the main arm of the Firtina), its catchment is less developed than that of other rivers of comparable size, and consequently water quality (especially as regards turbidity) is generally good. Two sites were identified:
The existing rainbow trout farm at Çağlayan Village, owned by Mr Gürhan Süleymanagaoglu. The farm uses wooden hatchery troughs, concrete raceways and earth ponds to produce portion fish as well as fry and fingerlings for sale to other private farms.
The unit is well run, and the owner is a local man genuinely interested in helping any project aimed at improving stocks of seatrout in the area. The water supply to the farm is taken from the river via an open canal. This currently carries about 0.5 m3/sec, but the farm has the right to extract more water from the river (up to the total flow). The intake canal could easily be enlarged or a new one built to provide more water for expansion by gravity. In addition there is a small spring supply suitable for use in the hatchery. Land is also available at the site. Mr Süleymanagaoglu owns 2 ha of suitable land, and there is more nearby belonging to other owners. The road to the farm is currently a good standard unsealed track, and is scheduled for tar-sealing during 1990. All services are already on site. The owner has expressed enthusiasm for cooperating in a seatrout enhancement project. The consultant's reasons for strongly recommending a partnership arrangement with this existing trout farm are:
Cost-effectiveness. It would be cheaper to expand the existing farm, where all services and some spare water are already available, than to develop a “green field” site.
Track record. The water quality and supply have already proved themselves over years of commercial operation.
Management expertise. This is perhaps the most important consideration. The existing rainbow trout farm is well run and successful, and the technology and skills required for seatrout culture will be basically the same. In the consultant's opinion the success of a new seatrout hatchery will be much more likely if its management is placed in the hands of commercial producers with proven competence rather than entrusted to relatively inexperienced (and perhaps less well motivated) government workers or researchers.
On the opposite (east) bank from Mr Süleymanağaoğlu's farm, and slightly upstream, is an area of about 3.5 ha of usable land adjacent to the river, currently under nut trees. It belongs to Mr Enver Ata Bilgin and other owners. The site could draw water of already proven quality from the Çağlayan river upstream of the existing farm's inlet, but discharge its waste water below the other farm's intake - thus avoiding any risks of disease transfer, pollution, etc., between the two fish farms. The site has easy access to power and telephone connections, but is situated at the bottom of a high, steep embankment below the existing road. Construction of a track from the road to the site would add greatly to costs. In addition, because of the land's tree cover it was impossible to assess by eye how far upstream it would be necessary to place the intake structure in order to obtain water by gravity. Before this site is considered further, therefore, levels must be measured. Mr Süleymanağaoğlu has stated that he would not lodge any objection to the siting of a seatrout hatchery at this location.
If either of the above locations is chosen for development, good sites are also available, both adjacent to them and downstream, on which a permanent fish trap could be built to capture mature seatrout on their way upstream. This will be necessary both to secure supplies of broodfish and to help assess the results of releases on the population through mark/ recapture studies (see below).
Since many returning fish will probably be attracted into the outflow channels from the fish farm(s), it is suggested that the best place for construction of the trap is downstream of Mr Süleymanağaoğlu's unit. There is a good site available less than 100 m away, just downstream of the bridge carrying the road over the river. In this or a nearby location, farm staff could conveniently look after the trap, and transport of captured fish to the nearby farm would be easy.
2. Firtina River. The consultant has placed this river as second choice to the Çağlayan because the more frequent turbidity in the Firtina renders its waters of poorer quality. To find a site where the main flow is normally clear it is necessary to go a long way upstream, to areas where the road may sometimes become difficult during winter because of snow, and which seatrout may not currently reach. Nevertheless, it is believed that a very good site was identified adjacent to the primary school at the village of Senyuva, about 15 km upstream of Çamlehensin. Here at least 5 ha of suitable grassland is available next to the river. Water can be supplied to the site by gravity from the river, and also from a steep spring-fed stream which joins the Firtina near the school. The springs themselves are 5–6 km away. During the consultant's visit the stream's flow was calculated at about 400 l/sec, and local people claimed it does not fall much below current levels at any season. Since this short stream is likely to remain clear even in times when the main river is in flood, and may also have a temperature advantage in winter, this extra supply would be a great asset to a seatrout hatchery. The owners of the land are Messrs Atilla Güneri, Mustafa Taner, Muhlis Burunoglu, and Ömer and Halil Tekin. Though the site is upstream of the Forestry Department's new seatrout hatchery, the outfall from the proposed site could in no way endanger the Forestry Unit, which draws its water supply entirely from two small side-streams off the main river.
The location described above would make an excellent site for a hatchery. Nevertheless, for the purposes of a seatrout enhancement programme it is inferior to the Çağlayan sites because the fish trap would have to be built a long way downstream of the hatchery (both to find a building site and because seatrout may not migrate upstream as far as the hatchery), making it difficult for hatchery staff to work and supervise it. Also, the road is difficult in winter.
Downstream of Çamlehensin, where the road is much better, few potential building sites are available due to the steep-sided nature of the valley. However, two sites were found where very small hatcheries could be built, both in places where the river falls steeply, allowing a gravity water supply to be installed easily and cheaply. Both sites have good road and service access. The furthest downstream is a 0.5 ha site just below Dekoya Village, on the eastern side of the river. The owners are Ismail and Ferhat Kalay. There is a 2–3 m high waterfall immediately above the site. The second site is a l ha strip a little further upstream, between the main road and the river just below Köprü Basi village. Both these small sites could be cheap to develop, but would require a water filtration system for eggs and fry during periods of high turbidity.
Kapistre River. Though water quality is considered better in the Kapistre then the Firtina, and the catchment is much less developed, this river is given lower priority as a potential hatchery location due to the scarcity of usable building sites. Only one suitable area was identified, close to the village of Dereüstü. Here a rough track (requiring upgrading) leads from the road for about 100 m to the river bank. Adjacent to the river is a 0.5 ha piece of state-owned land, currently under timber and used as a recreational area for picnics. The usable area could be enlarged by levelling adjacent land currently used for growing tea. The land registration numbers of adjacent blocks are 18–23, blocks 754–760. Services are available nearby, but land clearing and preparation work in this area would not be easy due to the very large boulders underlying the thin soil.
Findikli (= Arili) River. Potential hatchery building sites are also scarce around this river, and only one was found. This is an area of at least 5 ha located at a bend on the river between the villages of Monastir and Hara and on the opposite (west) bank. There is a rough but passable track to the site and power and telephone are available. However, this site is currently under nuts and timber, and as with the second Çağlayan site it was impossible to assess by eye how far upstream it would be necessary to place an inlet structure in order to obtain water by gravity. Measurement of levels is therefore necessary before this site can be considered further.
Baltaci River. There are several usable areas of gently sloping accessible land close to the east branch of this river. A good example is an approximately 5 ha section between the road and river at Siraağaç village, just below the local school. Here a 700 m long canal has been constructed to carry 250–300 l/sec of water from the river to power a mill. For much of its length the canal is built on the side of the road embankment and runs about 2 m above land level. From this height it could easily serve hatchery tanks or raceways. Further similar but larger systems could be built here or at other nearby locations. The land described belongs to Ismail Bayraktar, and Ömer, Necati and Ahmed Cakuroğlu. The main concern about the Baltaci River as a potential hatchery site is water turbidity, and a filtration system would be required for supplies to eggs and fry.
All the above proposed hatchery sites have ample water throughout the year. Records of flow-rates are routinely made by the DSI, and data pertaining to the rivers of interest for seatrout hatcheries were collected during the project. They are now filed at the Fisheries Research Institute, Trabzon. A summary is given in Table 2.
The criteria for selection of a site for construction of an intensive hatchery for sturgeon were similar to those described above for the seatrout unit, i.e., adequate water quantity and quality, availability of a suitable building site with road access and services nearby, and a history of sturgeon reproduction in the chosen river. The following additional factor was also taken into account:
Ripe sturgeons are not easy to transport over long distances without damage. Thus a hatchery should be located as close as possible to the site(s) of capture for broodstock.
Sites endowed with all these attributes are rare, but one excellent location was found. This is immediately below the Suat Ugurlu dam, on the west bank of the Yeşilirmak River. Here a triangular piece of land of approxiamtely 1.5 ha is already supplied with a sealed road, electricity (including existing lighting) and telephone. Due to its proximity to the dam offices, surveillance of the site is easy, and water could be supplied in any desired quantity from above the dam by pumps or perhaps by gravity. The site is owned by the DSI.
Water quality data provided by the Samsun office of the DSI show that conditions are favourable for sturgeon rearing, i.e., average monthly temperatures from 8°C in January to 20°C in August (12°–16°C during the months of sturgeon spawning), pH 7.6–8.3, full saturation with dissolved oxygen, and electrical conductivity 350–500 micro-mhos cm-1. The water does not appear to require filtration before use in a hatchery.
Transport of sturgeon broodstock to the site would take approximately 1 1/2 hours by road from the mouth of the Yesilirmak, and 2 1/2 hours from the estuary of the Kizilirmak River. There is a possibility that sturgeon brooders may even be captured immediately below the Suat Uğurlu dam adjacent to the hatchery site.
Alternative sites were sought throughout the lower reaches of the Yeşilirmak and Kizilirmak, which would have the advantage of closer proximity to the expected main locations for broodstock capture, i.e., the river mouths. However, these places were found to have many disadvantages, e.g., lack of services, poor quality roads, pollution, and danger of flooding. In addition, these areas may be rendered unusable after the plans to divert water from the river into irrigation canals have been implemented, since they will lose much of their water supply especially during the summer. The only potentially suitable alternative site found was below the Derbent dam on the Kizilirmak River, but the future condition of this area was impossible to assess because building is still going on.
