Part 2.4. Biological pollution

The issue of biosafety is of versatile nature and great importance for the conservation of biodiversity. In addition to biotechnology, the following actual aspects of biosafety should be singled out:

• transfer of genetic information from domestically created forms to wild species;
• genetic exchange between wild species and subspecies, including the risk of genetic pollution of the rare and endangered species genofund;
• genetic and ecological consequences of voluntary and involuntary introduction of animals and plants.

For example, a biosafety risk assessment for mammals, i.e. risk of polluting the natural genofund with biotechnology products obtained on the basis of a mammal genome, has not acquired an urgent character so far. Though, in future, such risk should be hypothetically considered as part to the most general postulates of the biosafety concept.

Changing of inherited properties as a result of accidental or intentional breeding has a long history in human activities. In a number of cases (horse, cow), species that served as an origin for the artificial selection do not exist in nature. There is no direct channel of the genetic information exchange with natural populations of initial species. Predecessors or predecessor species of other domestic animals (pig, cat, dog) continue living in the wild, including habitats located in a close neighbourhood with their domestic pools. This problem is extremely pressing for Russia, especially for its anthropogenically transformed European part where under certain conditions successful hybridization between parental and domestically created species occurs resulting in fecund progeny (e.g. wolf-dog, wild boar-pig, forest-steppe cat-domestic cat hybrids). Practical experience shows that one of the most important prerequisites of hybridization and subsequent pollution of the natural genofund by wild species is disruption of the structure (ecological, ethnological) and mechanisms of their population self-control. If normal, these mechanisms prevent hybridization preserving natural priorities in reproduction. As follows from the above, it is rare and endangered species with their populations degrading that are under the highest risk of pollution. The best example is hybridization of a European subspecies of forest cat with domestic forms (note: domestic cat is likely to be an interspecies hybrid of steppe and forest cats).

Therefore, two approaches to the control over the genetic information transfer between domestic forms and rare species may be singled out:

• strict control over domestic forms spreading in the wild (catching of homeless animals and those grown wild) and liability of juridical and physical persons-owners of domestic animals;
• maintaining a normal structure of wild populations of potential genetic information recipients and natural protective mechanisms of populations.

Interspecies and intersubspecies hybridization processes are rather wide-spread phenomena. Yet, a degree and potential occurrence of hybridization as well as fertility of hybrid progeny are governed by the properties of the chromosome apparatus organization and genetic similarity of initial species or intraspecies forms and vary with various taxons.

A threat of interspecies hybridization for Russian aboriginal fauna is also characteristic of the regions with anthropogenically transformed environment and disruptions in population control mechanisms. Changes in habitat conditions can provoke interspecies hybridization, e.g. hybridization of Cervus elaphus and Cervus nippon in re-introduction sites of the latter in European Russia.

Biosafety problem still remains actual in the context of artificial interspecies and even intergenera hybridization. In most cases such hybrids prove sterile or with only one sex surviving, e.g. an intergenera hybrid of Bison bonasus and cow. Therefore, these experiments probably are not of much threat, at least now. Nevertheless, in certain instances when it concerns close species and when human control over the process is lacking, hybridization effects are hardly predictable. For example, some European populations of Cervus elaphus are hybrids themselves and there is a share of American wapiti in their genofund. It is interesting that nobody could predict a possibility of hydridization between Cervus elaphus and Cervus nippon as no hybridization had been noted in Far East where both species had close habitats.

Voluntary and involuntary introductions. A risk assessment for aboriginal population genetic pollution caused by introduced or re-introduced species or subspecies presents certain challenges. In Russia, re-introduction of species, which have grown extinct in individual regions for different reasons, into the wild is looked at as one of a means for the conservation and restoration of biological diversity. A lot of positive re-introduction outputs can be enumerated, among them are:

• formation of the Ovibos moschatus population on the eastern coast of the Taimyr lake (Krasnoyarsk krai);
• restoration of the Martes zibellina population in the taiga zone;
• restoration of the Bison bonasus population in the center of European Russia and on the Caucasus;
• return of Castor fiber to its former habitats in European Russia;
• return of Marmota bobac to its former habitats in the Russian steppe zone.

Considerable negative consequences for Russian biodiversity took place as a result of wide-scale experiments on the animal and plant introduction in the 1930-50s under the slogan of enriching Russian flora and fauna. A review of their genetic, ecological and other effects will enable future evaluation of real changes in Russian biodiversity brought by these actions. A lot of these changes proved hardly predictable. For example, multiple experiments on introducing mammals in new habitat locations resulted in species naturalization only in a few cases:

• Procyon lotor formed populations in Primorsky krai and Republic of Dagestan;
• Nyctereutes procyonoides assimilated in forests of European Russia, Caucasus and Far East;
• Castor canadensis formed populations on rivers and lakes in Republics of Karelia and Komi, in Murmansk and Leningrad oblasts, Khabarovsk krai, etc.;
• Mustela vison settled in the forest and forest steppe zones of European Russia and Caucasus where it forced out aboriginal Mustela lutreola;
• Ondatra zibethica assimilated in actually all water and circumwater habitats, except the Arctic Region.

Ecological and genetic consequences of involuntary introduction are even less predictable than those of re-introduction or voluntary introduction. Invasions of species-introducents can illustrate ecological crisis consequences primarily for Russian agriculture and forestry (Table 17). For example, for only a 35-year period of work of the former USSR Quarantine Service, the expertise of about 1 million imported plant freights revealed more than 1,000 species of various insects (mainly pests), about 600 species of disease-transmitting microorganisms (viruses, bacteria, fungi), and seeds of over 400 weeds (Annex 5.2.3-5.2.4).

Table 17 Examples of plant and animal species invasive for the Russian territory

Notes: o - negative impact on biodiversity, n - unknown impact; no - neutral or sometimes economically important; B - under control measures (chemical and biological anti-pest and anti-weed methods, hunting); N - no control measures.

Invasion rates of species-introducents can be judged from expansion rates of geographic ranges of both under-quarantine and voluntary introduction objects. For instance, during past 60 years Ondatra zibethica has assimilated in actually all regions of Russia - from tundra to arid zones, and Leptinotersa decemlineata has settled in agrolandscapes of European Russia and south of West Siberia since the 60-s.

A lot of other current transformation processes in Russian biodiversity that could be assigned, in a broad sense, to the biodiversity scope can be only roughly approached as the research in this area is not conducted and relative indicators are not employed in monitoring.

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