![\"\"](\"https:\/\/www.vtei.cz\/wp-content\/uploads\/2025\/02\/Hronkova-obr-1.jpg\")
<\/a>\nFig.\u00a01. The\u00a0Blanice River \u2013 habitat of\u00a0the\u00a0freshwater pearl mussel (photo: K. \u0158\u00edmalov\u00e1)<\/h6>\n
Therefore, RPs are understood as temporary projects at the\u00a0national level, the\u00a0purpose of\u00a0which is to achieve an increase of\u00a0abundance of\u00a0the\u00a0affected species above the\u00a0level of\u00a0threat of\u00a0extinction by combining various types of\u00a0measures. This level varies for individual species due to the\u00a0different types of\u00a0distribution of\u00a0residual populations, the\u00a0species ecology, the\u00a0strength of\u00a0the\u00a0influence of\u00a0threatening factors, etc. After achieving the\u00a0set quantitative goals, the\u00a0RP is terminated. However, it can also be terminated in\u00a0the\u00a0event of\u00a0its failure (extinction of\u00a0the\u00a0species) or its inoperability proven during implementation\u00a0[4]. Other active instruments in\u00a0nature conservation include regional action plans (RAPs). These are essentially RPs at the\u00a0regional level, which are developed for regionally endangered species or for nationally endangered species with a\u00a0regional occurrence. In\u00a0addition to the\u00a0RP and RAP for the\u00a0most endangered species, there is a\u00a0need to address in\u00a0a\u00a0coordinated manner issues related to the\u00a0protection of\u00a0other specially protected species, where there is a\u00a0conflict between human economic interests and the\u00a0impact of\u00a0these species. So-called management plans have been proposed for these species [4].<\/p>\n
There are many plants and animals in\u00a0the\u00a0Czech Republic that are directly threatened with extinction, and many of\u00a0them would certainly deserve the\u00a0support of\u00a0RPs. However, in\u00a0order for a\u00a0species to be a\u00a0so-called candidate species for an RP, it must meet several criteria that are given by Act No. 114\/1922 Coll., on Nature and Landscape Protection; e.g., it must be included among specially protected species according to Decree No. 395\/1992 Coll.\u00a0[19], or the\u00a0criterion is determined by the\u00a0Concept of\u00a0Active Species Protection Instruments\u00a0[5], such as the\u00a0fact that the\u00a0causes of\u00a0the\u00a0threat to the\u00a0species are permanent and removable, etc. These currently selected candidate species are also part of\u00a0the\u00a0aforementioned Concept\u00a0[5], which summarizes the\u00a0approach to the\u00a0preparation and implementation of\u00a0RP, management programmes, and RAP.<\/p>\n
Each RP includes chapters on the\u00a0species taxonomy, biology, and ecology, which describe the\u00a0demands on the\u00a0environment, way of\u00a0life, and the\u00a0cause of\u00a0the\u00a0threat to the\u00a0species. This is followed by the\u00a0chapter RP objectives and RP action plan, which is its most important and practical part. The\u00a0action plan deals with specific measures in\u00a0the\u00a0management of\u00a0the\u00a0habitat and the\u00a0species, species monitoring, and research and education, which are an integral part of\u00a0the\u00a0RP.<\/p>\n
There are currently 14 RPs adopted in\u00a0the\u00a0Czech Republic (seven for plants and seven for animals), two of\u00a0which are RPs for animals related to water. The\u00a0first is The\u00a0Freshwater Pearl Mussel Rescue Programme. The\u00a0current version was approved in\u00a02013 and is now the\u00a0third stage; the\u00a0first stage of\u00a0the\u00a0Margaritifera rescue programme [6] was running from 1993, followed by the\u00a0second stage [7] from 2000. The\u00a0Freshwater Pearl Mussel Rescue Programme is thus the\u00a0oldest approved and still ongoing programme. The\u00a0second water-related programme is the\u00a0Stone Crayfish Rescue Programme, which is the\u00a0newest approved programme in\u00a0the\u00a0Czech Republic (in\u00a02024).<\/p>\n
FRESHWATER PEARL MUSSEL<\/h2>\n
The\u00a0freshwater pearl mussel (Margaritifera margaritifera) is a\u00a0long-living freshwater mussel that is protected in\u00a0the\u00a0Czech Republic by Act No. 114\/1992 Coll., on the\u00a0Protection of\u00a0Nature and Landscape [20] and the\u00a0European Habitats Directive\u00a0\u2013 92\/43\/EEC [21] within\u00a0the\u00a0NATURA 2000 system. In\u00a0the\u00a0Czech Republic, the\u00a0freshwater pearl mussel was previously found in\u00a0the\u00a0Vltava, Elbe, Oder, and Danube river basins, often in\u00a0colonies of\u00a010,000 to 100,000. Currently, its main\u00a0distribution is limited to a\u00a0few sites in\u00a0southern and western Bohemia.<\/p>\n
The\u00a0average lifespan of\u00a0freshwater pearl mussels in\u00a0our conditions is around 50 to 80 years, depending on the\u00a0quality of\u00a0the\u00a0water environment. The\u00a0freshwater pearl mussel life cycle is quite complicated; for its successful development, the\u00a0parasitic larval stage of\u00a0the\u00a0species needs a\u00a0healthy population of\u00a0host fish\u00a0\u2013 brown trout (Salmo trutta m. fario). Juvenile freshwater pearl mussels spend the\u00a0first part of\u00a0their lives buried in\u00a0the\u00a0gravel-sand riverbed and only emerge on the\u00a0surface when almost adult (Fig.\u00a02). In\u00a0all developmental stages, the\u00a0freshwater pearl mussel is dependent on the\u00a0quality of\u00a0the\u00a0aquatic environment and the\u00a0associated natural communities. In\u00a0addition to the\u00a0requirements for water without pollution, its existence and reproduction depend on the\u00a0availability of\u00a0food, which is organogenic detritus arising in\u00a0adjacent habitats. In\u00a0practice, therefore, the\u00a0protection of\u00a0the\u00a0freshwater pearl mussel includes not only measures supporting the\u00a0population of\u00a0the\u00a0species and its hosts but also measures improving the\u00a0quality parameters of\u00a0the\u00a0aquatic environment, including the\u00a0surrounding terrestrial habitats with a\u00a0connection to this environment. Due to the\u00a0significant decrease in\u00a0the\u00a0number of\u00a0sites and the\u00a0overall deterioration of\u00a0their condition in\u00a0the\u00a0recent past, which has been documented since at least the\u00a01950s, systematic activities aimed at protecting the\u00a0populations and habitat of\u00a0the\u00a0freshwater pearl mussel were initiated in\u00a0the\u00a01980s. These were mainly locations in\u00a0the\u00a0Prachatice region, where the\u00a0largest colonies of\u00a0freshwater pearl mussel of\u00a0Central European importance have been preserved to date. The\u00a0decline of\u00a0freshwater pearl mussel populations and the\u00a0loss of\u00a0quality habitats is not just a\u00a0matter for the\u00a0Czech Republic, but a\u00a0pan-European problem [4].<\/p>\n
<\/p>\n
<\/p>\n The\u00a0RP objectives are based on the\u00a0idea of\u00a0nature conservation ecosystem concept, which consider the\u00a0conservation of\u00a0Margaritifera margaritifera to be successful only if it is conserved in\u00a0the\u00a0Czech Republic in\u00a0such a\u00a0state that it is viable as a\u00a0species and capable of\u00a0independent reproduction in\u00a0natural conditions. The\u00a0conservation of\u00a0the\u00a0species in\u00a0the\u00a0Czech Republic can be considered successful if at least two of\u00a0the\u00a0three Conservation Units (A\u0161, Blanice, Mal\u0161e populations; division based on genetic tests) manage to achieve a\u00a0state where natural reproduction of\u00a0the\u00a0freshwater pearl mussel will successfully take place in\u00a0conditions close to nature.<\/p>\n Currently, in\u00a0all locations in\u00a0the\u00a0Czech Republic where freshwater pearl mussels occur, semi-natural breeding of\u00a0old freshwater pearl mussel populations is taking place in\u00a0parallel with targeted interventions to improve the\u00a0condition of\u00a0entire freshwater pearl mussel streams. Targeted interventions include, in\u00a0particular, measures to improve water quality, anti-erosion measures, and changes in\u00a0vegetation cover around \u200b\u200bsprings and other parts of\u00a0the\u00a0stream, associated with the\u00a0adjustment of\u00a0forest management plans. Physico-chemical water parameters are measured at all monitored locations with the\u00a0freshwater pearl mussel occurrence. Management of\u00a0the\u00a0breeding and reproductive features in\u00a0the\u00a0Blanice, Lu\u017en\u00ed stream, and Zlat\u00fd stream continues in\u00a0the\u00a0form of\u00a0the\u00a0cross-section maintenance, food channels, mowing, and subsequent composting of\u00a0the\u00a0mowed material, including the\u00a0return application of\u00a0compost to breeding or food features. The\u00a0total number of\u00a0freshwater pearl mussels at individual monitored sites in\u00a0the\u00a0Czech Republic is approximately 14,500\u00a0individuals. Subadult individuals, which originate from natural reproduction, are currently found in\u00a0very small numbers in\u00a0the\u00a0Blanice, Mal\u0161e, and Rokytnice near A\u0161 town\u00a0[2].<\/p>\n The\u00a0stone crayfish (Austropotamobius torrentium<\/span>) is a\u00a0specially protected species according to Act No. 114\/1992 Coll., on the\u00a0Protection of\u00a0Nature and Landscape, classified as critically endangered according to Decree No. 395\/1992 Coll., and a\u00a0critically endangered species according to the\u00a0Red List of\u00a0Invertebrates of\u00a0the\u00a0Czech Republic<\/span>\u00a0[8]. At the\u00a0European Union level, it is a\u00a0priority species protected by Council Directive 92\/43\/EEC on the\u00a0conservation of\u00a0natural habitats and of\u00a0wild fauna and flora [9, 10].<\/span><\/p>\n Although the\u00a0occurrence of\u00a0the\u00a0stone crayfish in\u00a0our country is rarer than the\u00a0occurrence of\u00a0the\u00a0noble crayfish (Astacus astacus), its original distribution in\u00a0the\u00a0Czech Republic is not known. The\u00a0stone crayfish used to be even considered a\u00a0non-native species and its sites of\u00a0occurrence are being constantly discovered. As of\u00a0the\u00a0end of\u00a02024, 38 sites of\u00a0its occurrence were registered [10].<\/p>\n As a\u00a0critically endangered species, the\u00a0stone crayfish faces many negative factors. The\u00a0most significant of\u00a0these are crayfish plague and habitat loss. Crayfish plague, a\u00a0disease caused by the\u00a0oomycete Aphanomyces astaci, is fatal to our crayfish species\u00a0[11]. There is currently no effective treatment for this disease and under current conditions it is essentially impossible to prevent its spread. However, it is necessary to try to limit or slow down this spread. The\u00a0primary host of\u00a0this pathogen is non-native and invasive species of\u00a0crayfish originating from North America, which are themselves resistant to the\u00a0infection but are its vectors. There are currently three invasive crayfish species in\u00a0the\u00a0Czech Republic\u00a0\u2013 signal crayfish (Pacifastacus leniusculus), spinycheek crayfish (Faxonius limosus), and marbled crayfish (Procambarus virginalis). However, crayfish plague can also be transmitted by the\u00a0Chinese mitten crab (Eriocheir sinensis) [12, 13]. Moreover, these species are strong competitors of\u00a0native crayfish species (e.g. in\u00a0food, shelter, etc.). A\u00a0fundamental problem is that to transmit crayfish plague to a\u00a0location, the\u00a0presence of\u00a0infected crayfish is not necessary; the\u00a0spores can survive in\u00a0water for up to one month without a\u00a0host\u00a0[14]. Therefore, infected water, fishing equipment, machines, or animal fur are sufficient to spread the\u00a0disease. In\u00a0the\u00a0last five years alone, we have lost up to 20 % of\u00a0the\u00a0stone crayfish population in\u00a0the\u00a0Czech Republic due to crayfish plague [15].<\/p>\n Although crayfish plague is a\u00a0major threat, habitat loss is often a\u00a0more fundamental problem; however, it has a\u00a0much higher potential for elimination. These include inappropriate interventions in\u00a0riverbeds, water pollution, and siltation of\u00a0riverbeds with fine-grained material. These negative factors are also responsible for the\u00a0disappearance of\u00a0several locations where stone crayfish occur [10, 16].<\/p>\n For these reasons, the\u00a0RP for the\u00a0stone crayfish establishes measures which can positively influence the\u00a0population status of\u00a0this critically endangered crustacean in\u00a0the\u00a0Czech Republic. Given the\u00a0negative factors affecting the\u00a0stone crayfish, most of\u00a0the\u00a0measures concern management of\u00a0its habitat. It is necessary to ensure satisfactory water quality, which will be influenced by the\u00a0construction and parameters of\u00a0new and existing wastewater treatment plants, to further eliminate poisoning, to prevent silting of\u00a0the\u00a0riverbeds, and also to actively manage the\u00a0hydromorphological properties of\u00a0the\u00a0riverbeds. Active species management (i.e. the\u00a0individual as such), such as ex situ breeding, is not the\u00a0goal of\u00a0this RP. Management of\u00a0the\u00a0species will only be carried out in\u00a0the\u00a0event of\u00a0a\u00a0crisis, such as necessary rescue transfers in\u00a0the\u00a0event of\u00a0watercourse poisoning, drying out, during riverbed modifications, or as prevention against approaching crayfish plague\u00a0[10]. However, species management is also related to efforts to slow the\u00a0spread of\u00a0crayfish plague and to eliminate and eradicate invasive crayfish species, as well as mammals, such as the\u00a0northern raccoon [17].<\/p>\n Despite all these measures, public outreach and research activities cannot be neglected. Education is essential in\u00a0the\u00a0fight against invasive species, and greater awareness among fishermen, watercourse managers, and the\u00a0general public can have a\u00a0very significant impact on the\u00a0spread of\u00a0invasive crayfish species. People often rescue invasive crayfish species, thinking they are our protected species, and unknowingly help spread the\u00a0devastation that crayfish plague brings to populations of\u00a0native crayfish species [10, 18].<\/p>\n As already mentioned, watercourses are one of\u00a0the\u00a0most endangered habitat types worldwide. They represent a\u00a0complex and highly sensitive environment that is home to a\u00a0huge number of\u00a0protected and unprotected plant and animal species. By protecting specially protected species, such as the\u00a0freshwater pearl mussel and the\u00a0stone crayfish, we protect all animal and plant species associated with this habitat. With their sensitivity to environmental conditions and bioindication abilities, the\u00a0freshwater pearl mussel and stone crayfish are very important umbrella species for aquatic habitats [3, 4, 10].<\/p>\n Detailed information on the\u00a0annual evaluation of\u00a0the\u00a0RP for the\u00a0freshwater pearl mussel and the\u00a0exact wording of\u00a0both RPs can be found on the\u00a0Nature Conservation Agency website \u2013 www.zachranneprogramy.cz for individual species in\u00a0the\u00a0\u201cDownload\u201d section.<\/p>\n This article is implemented within\u00a0the\u00a0framework of\u00a0project No. SS02030027 \u201cWater systems and water management in\u00a0the\u00a0Czech Republic under climate change conditions (Water Centre)\u201d with state support from the\u00a0Technology Agency of\u00a0the\u00a0Czech Republic and the\u00a0Ministry of\u00a0the\u00a0Environment within\u00a0the\u00a0\u201cEnvironment for Life\u201d Programme.<\/em><\/p>\n An informative article that is not subject to peer review.<\/p>\n","protected":false},"excerpt":{"rendered":" Freshwater ecosystems are among the most threatened habitats in the world [1]. This is the result of many factors that, individually and in combination, directly affect the degradation of freshwater ecosystems. The biggest problem for these habitats is climate change. Its consequence is drying up, as well as many anthropogenic negative impacts, such as eutrophication, drainage, introduction of invasive species, and overall environmental degradation [1]. Given these facts, species inhabiting sensitive aquatic environments are among the most endangered plant and animal species in the world.<\/p>\n","protected":false},"author":8,"featured_media":34554,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[87],"tags":[3728,3727,3726,3723,3725,3724,3729],"coauthors":[3688,3689,403],"class_list":["post-34647","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-hydrochemistry-radioecology-microbiology","tag-bioindicator","tag-critically-endangered-species","tag-freshwater-ecosystems","tag-freshwater-pearl-mussel","tag-rescue-programmes","tag-stone-crayfish","tag-umbrella-species"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts\/34647","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/comments?post=34647"}],"version-history":[{"count":5,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts\/34647\/revisions"}],"predecessor-version":[{"id":34735,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts\/34647\/revisions\/34735"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/media\/34554"}],"wp:attachment":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/media?parent=34647"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/categories?post=34647"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/tags?post=34647"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/coauthors?post=34647"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}<\/a>\nFig.\u00a02. The\u00a0freshwater pearl mussel reproductive cycle. A\u00a0\u2013 a\u00a0sexually mature freshwater pearl mussel excreting a\u00a0parasitic juvenile stage (glochidia), B \u2013 the\u00a0glochidia attach to the\u00a0gills of\u00a0the\u00a0host fish, where they metamorphose, C \u2013 after approximately a\u00a0year, the\u00a0juvenile freshwater pearl mussel falls off the\u00a0host and subsequently burrows into the\u00a0bottom substrate \u2013 D (illustration: M. B\u00edl\u00fd)<\/h6>\n
<\/a>\nFig.\u00a03. A\u00a0colony of\u00a0freshwater pearl mussels (photo: O. Simon)<\/h6>\n
STONE CRAYFISH<\/h2>\n
<\/a>\nFig.\u00a04. An example of\u00a0stone crayfish habitat (BRDY PLA, photo: J. Hronkov\u00e1)<\/h6>\n
<\/a>\nFig.\u00a05. Stone crayfish (photo: M. \u0160tambergov\u00e1)<\/h6>\n
Acknowledgements<\/h3>\n