The Peipia River. Russia. Leningrad region
44th place in Biotope Aquarium Design Contest 2018
Russia. Artyom Boykov
Volume: 250 L
Dimensions: 100х50х50 cm
List of fishes: Salmo trutta, Margaritifera margaritifera
List of plants: Fontinalis antipyretica, Myriophyllum spicatum, Elodea canadensis, Nuphar lutea
Description of decorations: All decorations and ground were taken from a natural pond. There are pine driftwood and deciduous branches, probably alder here. The main layer of soil is fine, light yellowish sand, a layer of 10-15 cm in order for the mollusks to move freely in it. Rounded stones and gravel of various sizes were also added.
Description of equipment: External filter for aquarium JBL Cristal Profi e1501, pump 2800 l/h with a fine sponge. Regular lamp with two T8 lamps of 30W. Schego WS2 air pump, EHEIM Air Pump 400 and several points with air stones. For rheophiles, it is very important to saturate the water with oxygen and to make flow, so this is why this equipment was chosen. It is also very important to maintain a low temperature. But since it is not only a decorative aquarium, but also a scientific project, it is installed in the “Ecocenter” department where the temperature in the room is no higher than 18°C. Control of all parameters is carried out daily. And of course the volume of the aquarium will be increased when the hydrobionts are grown up. While the brown trout is quite young, this volume of water is quite enough for it.
Water parameters: The temperature is 14-16°С, TDS is 80. pH is 7, KH is 3, GH is 5, NH4 is 0, NO2 is 0, NO3 is 10-15.
INFORMATION ABOUT BIOTOPE
Description of the area surrounding the biotope: The Peypia River flows through the western part of the Kingisepp District of the Leningrad Region. On the territory of the Kotelsky reserve. Peipia flows out of the northwestern tip of Lake Kopanskoe and flows into the Koporskaya Bay of the Gulf of Finland. Peipia belongs to small rivers, its length is about 2.5 km, width is 3-5 m, the prevailing depths are 0.4-0.8 m (they reach 1.5 m only near a dam created by beavers). The river flows through a coniferous forest, on its banks there are small bushes of alder and other deciduous trees. On shady areas of the coast there are mostly ferns. Closer to the water there are reed and calf bog, various types of sedges. In its middle course the river passes under a highway, where its channel passes through two concrete pipes 1 m in diameter each. Beavers dams are found downstream, a coastal meadow with grass and shrub vegetation is flooded. Further downstream, the river is crossed by a forest road and there is a ford used by both pedestrians and sometimes cars. Below the ford in the forest, the flow of the river is calmer, there are areas with low flow.
Description of the underwater landscape of the biotope: Throughout its length, Peypia strongly meanders, creating significant differences in individual sections in the flow velocity: from places of almost stagnant water to shallows with a flow velocity of 0.7-0.8 m/s. This also affects the transfer of precipitation by the river and the distribution of soil types: from silted areas with detritus to sites with washed gravel, coarse-grained and very fine sand. The distribution of pearl mussels in the river Peypia is extremely heterogeneous. As a rule, their settlements on the bottom are located in “spots”, concentrated groups, where the composition and/or speed of the flow (both are interrelated) turn out to be the most favorable for them. The mollusks are immersed in the soil for about 2/3-3/4 of their length. The area of this particular cluster is only three square meters, here the mollusks create a total density of up to 220 ind./m2. The river in this place makes a bend, its current accelerates in the center and erodes the slope of pure sand in its bed. On this very slope there is a particularly dense cluster of pearl mussels. Closer to the shore there are fallen trees that inhibit the flow. Here there are dense thickets of Elodea and freestanding Nuphar. At faster sites, the Elodea grows tightly clinging to the ground, covering it with a solid carpet, which is absolutely not characteristic for it in normal conditions. On the course, Fontinalis antipyretica spreads, tightly attached to rare stones or bark everywhere.
Description of the parameters of the habitat: It is a shallow, sometimes fast and transparent river with fairly soft water (pH is 6.5-7.5, KH is 3, GH is 5). During the period of storms, the waters of the Gulf of Finland can be driven upstream by several hundred or more meters, and with a steady western wind even a reverse flow occurs and the brackish water of the Gulf of Finland rushes into the lake. This has a serious significance on the species and quantity of fish and plants.
List of fishes and invertebrates occurring in the nature biotope: Salmo trutta, Margaritifera margaritifera, Anguilla anguilla, Perca fluviatilis, Rutilus rutilus, Sander lucioperca.
List of plants found in the nature biotope: Fontinalis antipyretica, Myriophyllum spicatum, Elodea canadensis, Nuphar lutea, Calla palustris.
Threats to the ecology: In the northwest of Europe, up to the beginning of the twentieth century, pearl mussel was regarded as an important biological resource, the basis of traditional pearl crafts. Apparently, in this area, it was one of the dominant species of small and medium rivers with a rapid flow, with a rocky and/or sandy bottom, rapids and shallows. Earlier in the fish population of such rivers, referred by ichthyologists to the category of “salmon”, the main owners of pearl oyster larvae: Atlantic salmon, or salmon and brown trout, occupied a significant position. According to some data, the prosperity of pearl mussel and salmon fish populations in such rivers is connected with symbiotic relations between them. At the beginning of the twentieth century the number of populations and the range of M. margaritifera began to decrease. It was associated with increased anthropogenic load. The process of extinction occurred very quickly and by the beginning of the twenty first century 99% of all pearl mussel populations have disappeared. Currently, it is listed in the IUCN Red Book, in the Annex of the Bern Convention, as well as in the Red Books of Russia, Karelia, the Arkhangelsk Region, Murmansk and other regions. At the moment there are only a few dozen large self-replicating populations of M. margaritifera. They are preserved only in Russia, Scotland and the countries of Fennoscandia. In the autumn spawning period on the Peipia River, one can observe fishermen-poachers regularly approaching on off-road vehicles and catching the brown trout near the mouth of the river. Coming of spawning fish to the mouth from the sea can be very easily blocked by poaching networks completely, which probably was the main reason for the almost complete disappearance of the brown trout from the Peipia River, and it became a threat of catastrophe for the population of the European pearl mussel in this river. The Peypia River is still the “most pearl-bearing” river in the Leningrad Region, currently containing the largest population of European pearl mussels. Due to the small size and depths of the river, its proximity to roads and settlements, this population is also the most vulnerable. A single pollution of the river or lake Kopanskoe or one poacher, equipped only with rubber boots, can destroy this population in one day and forever. After that, there will be no donor populations of pearl mussel in the Leningrad region.
Sources of information:
1. Report on the State contract number D17ZPK14 SPb of 04/20/2017 “Investigation of the status of protected species in the reserves of the Leningrad region: European pearl mussel”
2. Research work of the Department of the Ecocenter of the Kolpinsky District of St. Petersburg “Study of the state of the European pearl mussel in the Kotelsky Specially Protected Natural Territory” “Keeping European pearl mussel and brown trout in aquaculture”