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The aim of the study was to determine the effect of increased stocking density on the growth and survival of larval asp, Aspius aspius (L.), and European chub, Leuciscus cephalus (L.), during mass rearing under controlled conditions. Fish larvae were obtained during artificial spawning at a hatchery. The larvae were reared for 21 days in a semi-closed recirculating system at a water temperature of 25°C. They were stocked at four densities (50, 100, 150, and 200 indiv. dm-3) and were fed freshly hatched Artemia sp. nauplii. The fastest growth rate for both species was obtained at the smallest stocking density (ITL = 0.67 and 0.58 mm d-1 for asp and chub, respectively). The highest mortality of larval asp was recorded at the density of 200 indiv. dm-3 (11.68%), and for chub at the density of 50 indiv. dm-3 (40.4%). The results obtained indicated that the stocking densities applied do not have an impact on larval growth or survival in the first week of rearing.

Hunting is a unique form of activity in rural areas with a high proportion of forest areas, which involves nature conservation and meets social needs for recreation and the preservation of traditions while being an important part of economic activity. The presented study results, based on a literature review and questionnaire surveys conducted among hunters associated in hunting clubs in the north-eastern part of Poland, provide the basis for a discussion on the socio-economic significance of hunting, both in the country and throughout the European continent. Based on the results presented in the paper, it can be concluded that the number and density of hunters differ in individual countries. Moreover, hunting is practised in Europe by almost 7 million people, of which 127,000 are in Poland, and is a typical male activity. Most hunters in Poland and other European countries are professionally active inhabitants of rural areas, aged approximately 50 years, with several years of shooting experience and an income exceeding average values. Hunting is an important part of socio-economic activities, particularly in rural areas. It is estimated that in the EU alone, hunting can be worth approximately EUR 16 billion, and creates 100–120 thousand jobs. The most recent results of studies conducted in certain EU countries and the wide range of services provided by the hunting sector indicate that these values may be considerably higher. Regarding Poland, despite the centralised game resource management system, there are no extensive studies of the economic significance of hunting, and the official data are limited to a few basic indices related to hunting statistics. As indicated by the study results presented in this paper, in Poland, hunting-related expenditures are clearly lower than the European average and, thus, the economic significance of hunting is relatively low in this country. Despite this, it is a hunting community that, as a result of the adopted system solutions, is responsible for the functioning of reasonable game management while significantly affecting the management of the vast majority of rural areas.

The profitability of rearing larval asp, Aspius aspius (L.), ide, Leuciscus idus (L.), and dace, Leuciscus leuciscus (L.), was assessed in a system of 12 aquaria with a combined volume of 600 dm3. Two feeding variants were used: a) natural feed exclusively; b) natural feed plus formulated feed after seven days of rearing. All rearing variants were profitable and posed relatively low financial risks. The variant in which only natural feed was used was the most profitable. The savings incurred by the addition of formulated feed did not offset the profit lost from lower larval stock survival rates. In light of profitability, the most important aspect of larval rearing was the price of the stocking material, which was 250% higher for asp than for ide or dace. In both feeding variants, asp rearing was the most profitable and the values of the indices used to describe profitability were the best.