First water sampling in 2023 (Brdy Protected Landscape Area)

Author: Petr Hanzlík, Published: March 16, 2023, 1:15 p.m.

On 15 March 2023, the first water samples for basic monitoring were taken at the ponds in the Brdy Protected Landscape Area. This monitoring includes: determination of phytoplankton and zooplankton, physical-chemical water parameters and dissolved nutrient content. The sampling was carried out in the ponds Kolvín, Výtažník, Šindelka, Gricák and Ledvinka.

Rescue the meteorological station.

Author: Petr Hanzlík, Published: March 16, 2023, 12:46 p.m.

Strong winds, which reached gusts of up to 70 km/h on Monday 11 March 2023, overturned the meteorological station on Kolvín pond. The accident is being urgently solved in order to put the station into operation as soon as possible and to maintain the continuity of measurements.


Cutting down of woody plants

Author: Luboš Pechar, Published: Feb. 2, 2023, 5:36 p.m.

On 1 February 2023, the ponds Výtažník, Šindelka, Gricák and Ledvinka were cleared of woody plants (mainly alder) and shrubs (mainly bramble). The project activity was implemented by the Jakub Krčín Secondary School of Fisheries and Water Management, whose students improved their skills in operating a chainsaw and brush cutter as part of their practice.

Barrier against the invasive species in the NPP Vizír

Author: Petr Hanzlík, Published: Jan. 19, 2023, 3:06 p.m.

The Vizír National Nature Monument has been facing the invasion of the common sunfish (Lepomis gibbosus), the American catfish (Ameiurus nebulosus) and the topmouth gudgeon (Pseudorasbora parva). This has a negative impact on the whole ecosystem, especially on aquatic invertebrates.

In order to prevent these species from entering the basin, we had a special device installed at the inflow to the pond. This device consists of:

  • a double row of gates
  • a 1 cm wide grating
  • a netting sleeve frame of 4 millimetres mesh and a total length of 10 metres.

The grating prevents the entry of larger objects (sticks, leaves) and animals (amphibians and larger fish). The sleeve catches the fry of invasive fish from the basin. In a tributary pond like Vizir, this device must be cleaned at least twice a week of detritus that passes through the grating and gets caught in the net. During the first cleaning, the sleeve was found to be effective in barring the entry of both Lepomis gibbosus and Pseudorasbora parva.

Standardisation of zooplankton sampling methods

Author: Marek Baxa, Published: Sept. 23, 2022, 1:10 p.m.

On 21.9.2022, a determination workshop for zooplankton was held at ENKI within the RAGO project with the participation of other project partners. The main objective was to unify sample processing methodologies. Different approaches to the evaluation of zooplankton samples were discussed with a view to further use of the results. Sampling and processing is different for economic (feeding pressure), scientific (biodiversity, biomass, ecosystem services) and other purposes. It is necessary to treat differently samples from deep or shallow waters and from oligotrophic to hypertrophic reservoirs. In addition, the distribution of zooplankton in the reservoir needs to be taken into account with regard to its patchiness and further recovery. Methodological procedures for formalising the processing of microscopic samples and interpretation of results were also discussed. The afternoon part of the workshop was devoted to the practical determination of microscopic samples.

Fish farming within the project

Author: Petr Hanzlík, Published: Sept. 23, 2022, 12:07 p.m.

One of the project’s objectives is to protect fishpond ecosystems. This requires finding a harmony between the object of protection in the area and fisheries management. Fish are a natural part of the aquatic environment and play an irreplaceable role. ENKI, o.p.s. tries to use disappearing or even endangered fish species for so-called bio-manipulation measures.

In this project, we manage in different geographic regions. When designing the fish stocking, we take into account the native species present in the catchment, the constraints resulting from the object of protection, the fertility (potential overgrowth of unwanted vegetation). The proposed stocking is then consulted with the relevant authority of the Protected Landscape Area or AOPK.

In the past season, we focused on the development of individual communities (plants, amphibians, insects, fish...) under conditions of minimal, extensive management at almost all sites. Next year we will adjust the stocking in accordance with the results obtained in the first year of the project.

This year (2022), together with FROV, we succeeded in artificially spawning crucian carp. We obtained approximately 0.5 million bagged fry. The reared fish will be tested for genetic purity. In case of good results, these fish will be stocked into the Vizir NPP to replace the missing carp stock. Another species we are dealing with in our project is the common sunfish. This once abundant fish should replace the invasive Eastern Sunfish in our managed ponds. Our aim is to find a rearing system for juvenile common candace in polyculture with the common minnow. The fry of common sunfish is obtained by summer netting. This autumn we would like to catch a generational brook trout brood, which should ensure the return of this interesting species to the ponds in the Brdy protected area. Unfortunately, we have so far been unsuccessful in breeding the gudgeon. We will also pay considerable attention to this species in the coming years.

Phytocoenological survey 2022

Author: Luboš Pechar, Published: Sept. 18, 2022, 3:45 p.m.

Phytocoenological surveys were carried out between 20 and 28 August 2022 to determine the initial status of the higher aquatic plant communities.

At all ponds separate plant communities were assigned coordinates using GPS and within them 3 m squares were randomly delineated. In each square, we made an inventory of all species and determined their cover as expressed by the Braun-Blanquet scale. We complemented these data with an overall inventory of higher plants, for a more complete list of local biodiversity.

We plan to repeat the survey twice next year. The first time in late spring and the second time at the peak of the growing season - again in the second half of August. We will place the results of this and future surveys on individual pond cards.


Project kick-off

Author: Marek Baxa, Published: Sept. 18, 2022, 3:43 p.m.

This year, the long-prepared project Nature-friendly fisheries management as a tool for the protection of valuable pond ecosystems was launched. The ambitious idea of linking nature conservation interests with fisheries management, which has been developed over many years, is now becoming a reality. The project will be carried out in a consortium of four institutions - ENKI, o.p.s, the Faculty of Fisheries and Water Conservation South Bohemia University, the Secondary School of Fisheries and Water Management Jakub Krčín in Třeboň and the Bundesamt für Wasserwirtschaft.

The project is scheduled to run from April 2022 to April 2024. The focus of the project is the management of leased ponds from the AOPK ČR and Vojenské lesy a statky, s.p. The sites are located in the protected areas of the Třeboň Protected Landscape Area, the Brdy Protected Landscape Area and the Slavkovský les Protected Landscape Area. On the 12 ponds included in the project, we want to verify the composition and size of alternative fish stocks that will meet the interests of nature conservation with economic self-sufficiency. The proposed management methods are based on the long-term experience of the partners and on already implemented projects, not only on basic research.

The project framework consists of the key activities. In addition to the project management, management interventions will be implemented at the sites, data on biocenoses and physical-chemical water parameters will be collected and provided. Management interventions will be made to support and expand the disappearing native fish species, as well as materials transfering scientific research findings into real practice. An important activity will be the project propagation.

Follow the implementation on the project website or on the Rago - Pond Conservation Facebook profileor youtube.

The ambition is to create a platform, which represents the idea of sustainable fisheries management. The project is in full swing, so fingers crossed or get involved.

Marek Baxa, project manager.