ЗМЕНШЕННЯ ЧИСЕЛЬНОСТІ ТРАВ’ЯНОЇ ЖАБИ (RANA TEMPORARIA) ЯК ПОКАЗНИК НЕСТАБІЛЬНОСТІ ЛОКАЛЬНОЇ ЕКОСИСТЕМИ

Abstract

In the 21st century, the existence of many species of amphibians on our planet has become quite problematic due to a number of adverse environmental factors of both natural and anthropogenic origin. Amphibian fauna in Ukraine is not an exception. By conducting a series of field studies and observations, the author has established changes that occurred in the population of the grass frog (Rana temporaria) in the territory of the Lypnyky Forestry of the State Enterprise "Lvivlis". From 2005 to 2019 a number of field studies were conducted and the fact of a sharp decrease in the number of this species was established. During 2005-2009, the number of frogs reached 16 individuals per 1,000 m route. In the last few years, the number is 0.1 individuals per 1000 m of route. The drying up of reservoirs in which amphibians lay eggs spawned a reason for the low success of young frogs after the metamorphosis. First of all, we are talking about large, previously stable reservoirs and, to a lesser extent, ephemeral forest puddles. Over the last 5-7 years, the number of inhabitants has increased significantly in the study area. We are talking about the villages of Solonka, Lypnyky, Kovyri and others located near the forest. Thus, due to the rise of population, the volume of sewage drains also increased. This is a major cause of pollution and degradation of wintering frogs. Due to the low level of oxygen in local ponds, it has become virtually impossible for amphibians to winter. In 2019, due to the drought, we determined the death of caviar laying in different places of the Lypnyky forest. In one of the locations where thousands of frogs metamorphosis successfully completed ten years ago, spawning of single individuals occurred with complete loss of eggs. Therefore, we have obtained and summarized valuable data for a long period of research, formed a prediction for the population of herb frogs for the future. We believe that once numerous species in the Lypnyky forest, in the next few years will be on the verge of extinction, in some forest quarters completely cease to occur. The instability of the local ecosystem prevents the successful existence of amphibians, which requires two environments in the life cycle - terrestrial for spring and autumn habitat and aquatic for reproduction and wintering.