Across the world, biologists have been pressuring environmentalconservation institutions to protect endangered species. However, itis a common trend to see intense efforts of protecting endangeredspecies, only, after a big number of them succumb to humanactivities. Some animals have become extinct through human effortswhile others are on the verge of experiencing a similar fate. Theextinction of some species in the ecosystem always leaves a gap. Thebiological effects may be gradual and only understood by biologists. People interfere with the habitats of the European undergroundsquirrel because they view them as unnecessary in the environment andtheir activities results in drastic reduction of the affectedorganisms, therefore, causing an imbalance in the biodiversity.
According to the National Wildlife Federation, biodiversity refers tothe variety of life. Scientists look at diversity in differentlevels. It may refer to all the species of animals and plants in theentire world or the population in a given ecosystem (Sala 1770). Thedifferent organisms that live in a certain ecosystem interact tocreate a balance. Scientists may also look at biodiversity by thespecies present in a given habitat. Species can interbreed and giverise to a fertile offspring. Biodiversity encompasses all the speciesliving in a given ecology.
Biodiversity can be divided into genetics and ecological. Accordingto Sala, genetic biodiversity involves the variation that existswithin a given species (1772). For example, all dogs belong to thesame species. However, their genetic composition determines theircolor and physical outlook. Ecological biodiversity is theinteraction of ecosystems, natural communities and habitats(Cardinale 59). It refers to the way different species interact witheach other and their environment. According to Cardinale, researchersestimate that there are about 9 million species on the planet (59).Tropical ecosystems have wider biodiversities than the tropical andboreal environments. The depletion of some species occurs fast due tohuman efforts, thereby, resulting in an imbalance. The components ofthe ecosystem that interact with the depleted species suffer from thedevastating effects of imbalance.
Importance of Biodiversity
First, biodiversity assists human beings to live healthy andfulfilling lives. It is in an ecosystem that human beings derive thedifferent types of food (Pereira 277). Without biodiversity, thevarious plants and animals that sustain them would be absent. Forexample, flowers that produce grains depend on pollinators and otherorganisms in the soil. Each final product is a result of a complexinteraction between various species.
Secondly, most of the discoveries in the medical field, that aremeant to prolong life and cure diseases results from numerous testingof plant and animal biology and genetics. According to Pereira,every time a species becomes extinct, researchers may never know ifit would be helpful to human beings (279). Additionally, biodiversitymakes the environment safe through a natural and non-manipulatedinteraction of different species. For example, some processeslike air purification and absorption of chemicals in wetland takesplace because of a rich biodiversity.
Biodiversity also enables an ecosystem to adjust to naturaldisturbances, including, fires, floods, sewage, garbage, oil spillsand drought. Pereira also advises that the changes in the environmentcan have detrimental effects on the different species if they are notcontrolled (282). Components of the ecosystem, including, bacteriaand other bigger forms of life, break down and assimilate the foreignelements in an ecosystem. For example, species found in wetlandsharbor qualities that break down and absorb pollutants in the water.The water becomes safe for the consumption by other organisms livingin that ecosystem. However, large quantities of pollutants destroysome species.
Development of Biodiversity
Biodiversity has gone through several phases of development. Sincethe first exhibits of life on earth were discovered, there have beenfive mass extinctions of biodiversity. According to Cardinale,scientists approximate that 99% of the organisms that were crucial intheir different ecosystems are now extinct (62). The Phanerozoiceon, which took place 540 million years ago, led to the massivegrowth of biodiversity. The Cambrian explosion led to the formationof multicellular phyla.
However, the following 400 million years experienced massiveextinctions. The Permian-Triassic extinction that occurredmore than 251 million years ago was the worst, and the vertebratestook almost 30 million years to recover. Additionally, the Cretaceousextinction event that occurred over 65 million years ago is one ofthe most common since it led to the extinction of dinosaurs. Theemergence of humans marked the gradual loss of biodiversity. TheHolocene extinction is the loss of biodiversity as a result of humanefforts. The destruction of the habitats occupied by various specieshas been the major cause of death. Human activities, including,clearing of land, massive dumping and releasing of effluents into thewater bodies have been a major cause of reduction of variousorganisms.
belongs to the family Sciuridae,and it is the only representative of the genus Spermophilus.It belongs to the rodent order, and it can be found in EasternEurope, Ukraine, Czech, Slovakia, Greece, Romania and Bulgaria (Janákand Matějů 2). The European Squirrel is a small animal that growsto a maximum length of 8 inches at maturity, and it weighsapproximately 300 grams. It has a slender body with a busy and shorttail. Its fur is dense and yellowish gray in color. The fur hides itssmall ears and its eyes that are located high on its head. Thesquirrels live in colonies, and they burrow in pastures or grassylands. They feed during the day, whereby, they look for seeds,shoots, and roots. They also feed on flightless invertebrates. Duringthe day, they are prone to predators. To avoid being caught unawareswhile looking for food, each colony has a sentinel that whistle uponsighting a predator. The European squirrel breeds in early summer,and it gives birth to a litter of five to eight young ones. Duringwinter and autumn, they hibernate. The length of the time they stayin hibernation depends on the climate. They build reserves of brownfat in preparation for winter and autumn (Slimena, Gedeonb, Hoffmanncand Suchentrunk 15).
European Ground Squirrel Habitat
According to Janák and Matějů, the European ground squirrel isfound in Central and South-Eastern Europe. It occupies an area lyingat an altitude of 2, 600 feet (4). It has very specific habitatrequirements. The animal requires short turf to make its dwelling.Such features are found on the steppes in pastures, parks, lawns anddry river banks. Changes in agricultural practices alter the physicalnature of the surface of the land the squirrels migrate in search ofbetter habitats. The International Union for Conservation listed theEuropean ground squirrel as vulnerable. Its population has decreasedin the last one decade as a result of human cultivation and clearingactivities. The population has dropped by more than 30%, and if theconservation stakeholders do not implement efforts to protect thesquirrel, it will gradually edge towards extinction (Janák andMatějů 4).
Importance of European Ground Squirrel in the Ecosystem
Just like other organisms of different species, the European groundsquirrel offers various benefits in the environment. First, as asmall animal, the squirrel is prey to birds, including, hawks,eagles, and falcons. According to Janák and Matějů, their presenceis, therefore, important for the birds and their decrease may lead tothe reduced number of their predators (6). The presence of thesquirrels reduces competition on other sources of food. Since thehawks, eagles, and falcons also feed on other small rodents, the 30%reduction in the population of the squirrels is likely to result inthe reduction of other rodents that these predators target due toincreased competition for food in a given niche (Slimena et al. 19).
Secondly, the European squirrel is essential in an ecosystem as ithelps in seed dispersal. The squirrels feed on live seeds, such asthe tine pine and Scots pine among others, which germinate when theyfall on the ground. During summer, when food is plentiful, thesquirrels bury some of the seeds in holes so that they can retrievethem after the winter (Janák and Matějů 6). The squirrels do notalways retrieve the seeds hoarded. Once forgotten, the seedsgerminate. They are, therefore, agents of seed dispersal and renewalof some plant species. Some trees shed seeds that have limitedchances of sprouting. However, when dispersed to other fertileplaces, they sprout, leading to the distribution of the plantspecies. Baltag also agrees that some invertebrates are specializedto co-exist with the squirrels (99). They include the Coprophagousbeetle that feeds on the excrement of the S. cells. The oldburrows are also homes to other endangered species, including, theGreen Toad (Bufo viridis) and the smooth snake (Coronellaaustriaca).
What has happened to the European Ground Squirrel?
Janák and Matějů provide that the number of the European groundsquirrels has been decreasing steadily since 2000. The population hasdropped by more than 30% (2). First, changes in temperatures haveaffected the habitat of the S. citellus. There have beentemperature changes in different regions, primarily, due to theeffects of global warming. The European ground squirrel is tolerantto high temperatures and dry climates. They avoid the temperatures byretreating to the burrows. However, it is notable that the number ofhours that the squirrel spends looking for food reduces (Gedeon 5).Also, extreme environmental conditions, such as an excess amount ofrain, can destroy a whole colony. In addition, a higher amount ofprecipitation during winter, which is experienced in parts of Greece,may cause the ground water to rise, and this makes the environment inthe hibernation chamber intolerable. Consequently, it is also a majorcause of the reducing population.
Secondly, agricultural activities have been a threat to the existenceof S. citellus. According to Janák and Matějů, in somecountries such as Poland, agriculturalists in agric-environmentschemes are not sensitive on the protection of rodents, and theyconcentrate on the protection of birds (9). The farmers prefer doingtheir mowing in July, and they till the lands extensively. Gedeonindicates that the idea has affected the cycle of the squirrel sinceit prefers short grass during the month of June. After mowingextensive lands, the squirrels are left devoid of enough cover toprotect them from predators. Their number has been reducingsubstantially during the mowing months because the enhancedvulnerability to the predators.
Also, S. citellus has been under the threat of habitatavailability as a result of urbanization and the sprouting ofresidences in places that used to be grasslands. Since the coloniesmay still get a place to build burrows near the residential areas,they have been subjected to inadequate food supply and increasedconflict with human beings (Janák and Matějů 16). Furthermore, asignificant number of squirrels have lost their lives to traffic inthe residential areas. In the residential areas, it is notable thatother organisms that live in mutual association with the S.citellus either migrate or become extinct. They cannot,therefore, exploit the environment fully. Gedeon also agrees thatthe depression of space and reduced genetic exchange between colonieshas led to the extinction of the species in some areas (97). In aperfect ecosystem that does not suffer from external threats, thereis a balance between the numbers of organisms. However, externalpressure leads to a conflict between the species. S. citellushave suffered from increased predation from domestic animals andpoaching. Also, the human infiltration activities into their habitatshave increased the cases of poisoning, trapping, and diseases.
The Need for the Prevalence of the European Ground Squirrel
There is a need for the prevalence of the S. citellus population. Inthe natural environment, the interaction between the squirrels andother organisms is controlled and balanced. According to Gedeon, anoptimal population will ensure a constant supply of food for thefalcons, hawks and eagles (14). However, with the reducingpopulation, the competition for food will increase and the squirrelsthat remain will be in constant danger of predation. An optimalpopulation in the habitats will lead to a balanced predation ofdifferent preys. However, with a decreasing population, the birds andother predators are likely to consume other species at a higher rate,or starve in areas where there is inadequate food. The beetles andsnakes that rely on the burrows dug by the S. citellus forshelter are likely to get into a conflict due to the reduced numberof old hideaways. The Coprophagous beetles are likely to getinadequate food, and consequently, reduce in number because ofincreased competition for food.
The S. citellus conservation status on the biological levelhas not been adequate in various habitats. For the Alpine andContinental biogeographical regions, scientists term the state ofconservation as “unfavorable-bad.” In the Mediterranean andPanoramic regions, they refer to the preservation status as“Unfavorable-inadequate” (Janák and Matějů 21). It is anindication that the conservation bodies have not protected theendangered species to the required levels. However, there have beengenuine efforts in the various countries that have helped to slowdown the rate of extinction.
In Poland, article 17 of the Natural framework requires regularreporting of the status of the species in the country (Janák andMatějů 18). However, the reporting interval is long, and it may notadvise the key stakeholders at the appropriate time. For example, thelast reporting in the country was in 2007, when the status of thespecies was reported to be good. Despite the long intervals inreporting, S. citellus is among the animals listed in theHabitats Directive Annex II species. The Sites of CommunityImportance should cover the habitats of the animals in the list. TheEuropean squirrel is listed as a target species.
In the European Union, it is worth pointing out that the conservationof species refers to the actual coverage of the national populationsas mentioned in the Natura 2000. According to Janák and Matějů,approximately 45% of the S. citellus population is underprotection (23). However, a model conservation approach demonstratedthat the Natura 2000 areas are mostly located outside the potentialhabitats of the S. citellus. Most of the areas captured in themodel are in the woodland while the squirrel occupies grasslands. Forexample, in Australia, only 0.65% of the covered land is suitable forthe inhabitation of S. citellus (Gedeon 103). A similar trendis present in Vienna where Natura 2000 only covers a minor area inthe Northern part of the country.
Another technique pursued by various countries is the establishmentof protected areas. Apart from implementing the Natura 2000 thatidentifies lands for protection, protected lands have also beencrucial in the protection of the endangered species. In Bulgaria,there are protected areas that include Central Balkan, Vitosha,Strandzha and Rusenki among others. S. citellus are found inlarge numbers in the parks. Czech, Greece, Hungary, and Slovakia havealso implemented the protected area technique (Slimen 16). Thetechnique has deterred human interruption in the areas. Putting up ofairports, playfields, real estates and gardens are some of the commonhuman activities that are notorious in interfering with thesquirrels’ habitats.
Besides the demarcation of the protected areas, some countries haveimplemented national action plans. Poland and Czech are modelcountries with effective national action plans. In Czech, theMinistry of Environment developed guidelines, for the protection ofthe S. citellus, for the implementation at the local level.Gedeon indicates that the guidelines outline the need for ensuringthe existence of the European ground squirrel in the biggest possiblepopulation in specific localities. It also emphasizes on the Sitesfor Community Importance, as outlined in the Natura 2000, with theintention of enlarging the colonies. The Ministry of Environment alsosought to establish five Meta-population areas, with at least 2,500European Underground Squirrels each, by 2018 (Gedeon 102). Theeffectiveness of the method has not yet been ascertained since thefirst phase for monitoring will end in 2018.
Poland also has a working guideline developed by the Ministry ofEnvironment in liaison with other stakeholders. Although it is notlegally abiding, the ministry has implemented it, and it has shownearly fruits of success. Janák and Matějů indicate that the maingoal of the plan is to support the existence of S. citellus inthe country (27). The guidelines in Poland seek to establish six Metapopulation areas in a similar way to the national frameworkimplemented in Czech (Matějů 473). Since it was an agreementbetween various stakeholders, it is anticipated to roll out educationactivities in the local communities to sensitize them on theimportance of protecting the European ground squirrel. A similarplan also exists in Austria, which is financed by the Provincial andAustrian Government, under the Ministry of Agriculture andEnvironment. According to Matějů, the program involves themanagement of habitat, conflict resolution, monitoring ofconservation efforts and raising public awareness on the need for theprotection of S. citellus (475). Bulgaria, Hungary, Greece,Romania and Slovakia do not have nationally conceived policies forthe protection of the European underground squirrel.
Finally, some countries have implemented the translocation andrepatriation actions. The two have been the most common methods ofconserving S. citellus in the last two decades. Repatriationefforts are mainly implemented in areas with human interference. Thesquirrels are transferred to other areas to save the colonies.Slovakia and Hungary have model approaches to these two techniques.
There is more that the individual countries can do to protect theEuropean ground squirrel. Slimen provides that the Natura 2000, as ameasure for most of the European countries, is not effective inprotecting all the species (17). Some of them, such as the S.citellus, are left out since the habitats they occupy are notcomprehensively covered by the protection guidelines. Countries,through their ministry of environmental protection, should customizethe efforts. The rationale for this is that they are aware of theavailable habitats that are not covered by the Natura 2000.
In conclusion, the European ground squirrel remains an endangeredspecies, mostly due to human development activities. The squirrelsinhabit grasslands, and they usually feed on seeds and shoots. Duringwinter, they hibernate and reappear when temperatures rise. Humanactivities have displaced them, and the absence of strong protectionrules aggravates the problem. Natura 2000 indicates that only 70% ofthe European ground squirrels are presently remaining. There havebeen various techniques of protecting the species, including,establishing protected areas, repatriation, and relocation, as wellas, customized national policies. However, the techniques have leftvarious gaps in the protection of the species. Customized measuresthat expand on the sites of community importance can be moreeffective than the blanket protective strategies. The status of thecurrent case, therefore, remains endangered.
Baltag, EmanuelStefan, Gheorghe Zaharia, Lucian Fasolă and Constantin Ion.
. "Europeanground squirrel (Mammalia: Rodentia) Population from Eastern Romania:Density, distribution and threats." European ScientificJournal (2014): 94-101. Print. <http://eujournal.org/index.php/esj/article/viewFile/3262/3044>
Gedeon, CsongorIstvan. "Release site manipulation to favour European groundsquirrel Spermophilus citellus translocations: translocation andhabitat manipulation." Wildlife Biology 18.1 (2012):97-104. Print.
Gedeon, Csongor. Environmental factors and intrinsic processesaffecting habitat use of European ground squirrels (Spermophiluscitellus): putting science into conservation practice. Diss.Department of Biological Sciences, Northern Arizona University, 2011.Print.
Janák, M., P. Marhoul, and J. Matějů. "Action Plan for theConservation of the European Ground Squirrel Spermophilus citellus inthe European Union." European Commission (2013). Print.
Matějů, Jan. "Method of releasing and number of animals aredeterminants for the success of European ground squirrel(Spermophilus citellus) reintroductions." European journal ofwildlife research 58.2 (2012): 473-482. Print.
Pereira, Henrique Miguel. "Essential biodiversity variables."Science 339.6117 (2013): 277-278.
Sala, Osvaldo E. "Global biodiversity scenarios for the year2100." science 287.5459 (2000): 1770-1774.Print.
Slimena, Hichem Ben, Csongor I. Gedeonb, Ilse E. Hoffmannc, FranzSuchentrunk. Dwindling genetic diversity in European groundsquirrels? Mammalian Biology 77.1 (2012): 13-21. Print.doi:10.1016/j.mambio.2011.10.001