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The Black and Red lists of the Giant Mountains flora: Do the extinct and endangered plants have common properties?
Blahník, Jan ; Čihař, Martin (referee) ; Krahulec, František (advisor)
A list of extinct and endangered species of the Giant Mountains was published in 2009, which presents a uniform view of vascular plants on the Polish and the Czech sides of the mountains. This Bachelor's Thesis is focused on the most endangered and the extinct species, for which common properties were sought, while it was not clear, whether such properties actually existed. The Bachelor's Thesis evaluates factors that could be traced in literature. Data concerning the type of propagation, which is of key importance for the maintenance of species, however, are not stated in literature for the absolute majority of cases. Easily traceable data concerned the properties of the subsoil, biotope types and properties, life form (was not eventually evaluated), phytogeographic areas, degrees of vegetation and endemism. It cannot be expected that a comparison of the results would show conformity anywhere in the region of 100%, yet certain signs of common properties can be deduced from some results. For example, for one-fifth to one-third of C1 and A1 category species a common property is an acid substrate, 30-40% of C1 category species occur in oreophytic areas, for some 30% of extinct and endangered species, the common sign is their occurrence in meadow sites, 30-40% of critically endangered species occur in...
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The rescue of critically endangered fish species through manipulation with spermatogonia and oogonia
DOBROVOLNÝ, Petr
The transplant experiments described in this work may help to shorten the generation interval for long maturing endangered fish species and their more effective reproduction. Further, it is possible to preserve the separated spermatogonia and oogonia using a cryopreservation in liquid nitrogen. We conserve both paternal and maternal DNA and the gene pool of endangered fish species will not be depleted of maternal part. It's because we can freeze only sperm in the preservation of mature gametes. Fish eggs and embryos would not survive freezing. The described methods will be applied in the future to more effective rescue of critically endangered sturgeons by the transplantation of their germ cells into a Sterlet (Acipenser ruthenus). These methods can be suitable for application on other species of endangered fish in case of finding an appropriate recipient. As an example of our fish species is a European eel (Anguilla Anguilla). The Siberian sturgeon (Acipenser baeri) and the Sterlet (Acipenser ruthenus) were used as model organisms. For Siberian sturgeon the enzymatic dissociation technique, sorting of germ cells using Percoll gradient concentration and transplantation of sturgeon spermatogonia and oogonia were used. The results showed that the use of 0.3% of trypsin in PBS is optimal for dissociation of spermatogonia and oogonia, because this medium was dissociating the highest number of cells without reducing their viability. The separation of the early stages of germ cells has been successfully achieved by segregation in 10 to 30% of Percoll gradient with the help of centrifugation. After transplantation it was proved in spermatogonia as well in oogonia that they colonized the genital ridges of the host. The recipient became a chimera of a germ line, which can produce donor gametes throughout his life.
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Nesting biology of the Egyptian Vulture (Neophron percnopterus) in the zoo Praha and in European breeds
PACHTOVÁ, Tereza
The Egyptian vulture (Neophron percnopterus) is the smallest and the most threatened european vulture species. Recently, wild populations have been declining dramatically and monitoring is too difficult especially because part of the european population migrates. That is the reason why this species was declared endangered in the IUCN Red list of threatened species (IUCN, 2014). Prague zoo has great results in breeding of these birds of prey. In season of 2013, two juveniles were bred (1 male, 1 female) from 7 of all the Europe. Another juvenile was bred in Zlín-Lešná zoo. In the year 2013, Czech republic therefore bred almost a half of these vultures in european breedings (EAZA). In 2014 the results of breedings are also succesfull, more then half (13 juveniles in total, 3 from Prague, 4 from Zlín-Lešná) was risen in these breedings. Prague zoo has been keeping the egyptian vulture studbook for more than 10 years and is also in charge of the European endangered species programme for this vulture. For coordination improvement and to increase the succes of european breeding it is important to summarize the data and use them to provide better breeding conditions in other zoos. One of the program objectives is also the reintroduction of the animals back to its natural environment. This master´s degree provides summarization of etology research from seasons 2013 and 2014, short research of etology in Zlín-Lešná zoo, summarization of another european breedings and also assesment of all the breedings factors including those preceeding the nesting like incubation of the eggs, and birds hatching.
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