In my thesis I am dealing with problem of predation of great cormorant on fishery supplies in the Czech Republic. In the first part I explain the problem, describe historical development and current status. I also mention situation in other EU countries, which does have some characteristics similar with the Czech Republic. In the end of the first part I will quantify damage caused by cormorant and I will show how this damage could be estimated. In the second part I am applying scheme of institutional analysis called Institutional Analysis and Development. Firstly I will explain this scheme and then I will apply it on the problem of great cormorant in the Czech Republic. Aim of my thesis is to find a recommendation how organizations and institutions should be set in order to help to resolve this issue.

The thesis analyses compensations of damages caused by great cormorant (Phalacrocorax carbo) in fish farms in South Bohemian Region pursuant to Act. No 115/2000 Sb. till 2011. In the introductory section is described a development of population of nesting and migrating Great cormorants in Europe, particularly in the Czech Republic from the 80th of last century, and reasons for conflict between this species conservation and fish farming including legal conditions for compensation to pond owners and a development of compensation issues in the Czech Republic. This thesis assesses an overall status of the compensation of damages already paid in South Bohemia, analyses claimants according subject type and compares the amount of compensation of damages in relation to the number and the pond area including the frequency of submitted apllications by different types of claimants and the relationship to individual districts of South Bohemian Region. The survey in five chosen ponds in Třeboňsko region evaluates a current secondary damages caused by Great cormorants in the form of injured fishes obtained during fishing out.

Recreational fishing is a very important leisure activity and one of the most important ways how humans influence freshwater habitats and wild fish populations. Both fish-eating predators and socio-economic trends play a major role in recreational fishing. This thesis found that the Eurasian otter feeds mainly of small (5-10 g) and very abundant fish species of low angling value. In this case, gudgeon Gobio gobio dominated in the otter diet. The overlap between catches of otters and anglers was very low, and commercially important salmonids made up only 10 % of the otter diet by biomass. Cormorants also prey mostly on smaller (10-100 g) a very abundant fish species. In this case, roach Rutilus rutilus dominated in the cormorant diet. The overlap between catches of cormorants and anglers was also quite low. Commercially important fish species made up less than 10 % of the cormorant diet. Even though cormorants consume mostly smaller fish, they are potentially removing fish that serve as prey for piscivores, and they are also removing smaller fish that would grow into angling size. The Atlantic salmon Salmo salar reintroduction programme has not yet been successful. However, cormorant predation is not the main reason for its low success. The main problem is somewhere on the lower River Elbe in...

vi Abstract Continental subspecies of the great cormorant (Phalacrocorax carbo sinensis) is the Czech Republic's most important fish-eating predator. It causes damage to production fish, as well as sport fishermen and even after its removal from the Czech list of endangered species in 2013, it did not disappear from the spotlight of both local fishermen and researchers. This thesis evaluates the qualitative and quantitative composition of the cormorant's diet during winter 2011/2012 at two selected locations: the Žehuň pond (Kolín district) and Berounka river in the natural reserve Zábělá near Pilsen. This work studies the main components of cormorant's diet in the selected locations and evaluates potential fluctuations and changes in its composition during winter. The study also conducted the analysis of the proportion of commercially harvested valuable fish in cormorant's diet and studied its diversity of the species spectrum. The resulting data for the two sites were compared with each other and with relevant literature. Regurgitated pellets analysis, as well as analysis of diagnostic bones and fish remains located at the sleeping roosts (night roosts) were used for the diet analysis. It was found that at both sites roach was the most caught fish, but from the point of view of total biomass, it was...

Piscivorous birds are often blamed for causing significant damage to fish stocks. Various methods are used to determine the composition of their food, each of them has limits in its ability to determine the complete food spectrum. This work maps the complete food composition of 14 species of fish-eating birds with a method that is not commonly used. Method used in this work uses analysis of publicly available photos on Google.com. In addition to the complete composition of the food, the species composition of the non-fish part of the prey was also determined, and in the case of the Great Cormorant (Phalacrocorax carbo), also the length of the fishes it catches. The aim of this work is to reveal the usability of this method for these purposes. A total of 2350 retrieved photographs were analyzed. The results obtained by photo analysis are in all cases compared with data in the available literature. For representatives of heron birds (Ardeidae), the analysis of photographs provided good information on the food spectrum of individual birds and on the qualitative composition of the non-fish component. It also provided relatively good information on the diet of the White-tailed Eagle (Haliaeetus albicilla), but the bird part of the prey was slightly underestimated. In the diet of the Great Crested Grebe...