In theoretical part of the thesis biology, distribution, taxonomy and behavior of cetaceans are explained, with an overview of research methods having the highest implementation. In field work a photo-identification and tracking of baleen whales by transect method with application of observational research techniques of behavior is included. The experimental part of the research was carried out in the Skjálfandi Bay, where populations of baleen whales linger in large numbers for feeding in the summer time, which enabled the development of tourism industry based on organized boat tours for whale watching, now the fastest growing economy in Iceland. One of the goals of the study was testing the effectivness of the distance guideline proposed by Code of conduct that whalewatching operators implemented as a voluntary means to regulate and minimize the impact they have on whales. In order to do that whales were tracked opportunistically by using whale-watching boats as platforms. The second goal of the research was to determine the impact tourist boats have on whales who might respond to whale-watching boats by altering the direction of swimming. Williams (2002.) called this horizontal avoidance. Radial distance between boat and whale (r), angle of whale in relation to boat (), GPS, number and type of boats, whale species, weather and navigation conditions were recorded. Although the results shows that only 20% of baleen whales practice horizontal avoidance, when assessing the impact of whale-watching activity on baleen whales, large sample size and extensive experimentation is needed because of a high variability in whale behaviour. Throughout history, these mammals were extremely exploited and some of the species were brought on the brink of extinction. Therefore, the collection of data on their behavior, abundance, ecology and habitat use are extremely important for their conservation and protection.