Great snipe mainly feeds on invertebrates in the topsoil. However, the diet can also be supplemented with terrestrial invertebrates and fruit and seeds of plants (Cramp and Simmons 1983). Research conducted in Scandinavia indicates that great snipe is a food specialist, because up to 90% of his diet can be earthworms (Løfaldli et al. 1992). It is believed, however, that in the lowland population in highly hydrated habitats, where the presence of earthworms is not possible due to anaerobic soil conditions, a significant part of its diet can also be small snails and leeches. Studies on the occurrence of soil invertebrates, conducted in the vicinity of two leks in the Upper Narew Valley indicate that the largest share in the overall biomass of invertebrates - both from random and feeding sites were earthworms (75%), insect larvae and pupae (16.0%) and leeches and snails (4.0 and 2.7% respectively). Invertebrate biomass in soil samples collected from foraging grounds in 2013-2014 was higher (N = 188, 0.493 ± 0.703g; IQR = 0.020-0.656g; max. 5.801g) compared to random plots (N = 365 , 0.434 ± 0.551g; IQR = 0.058-0.621g; max. 4.284g), but these differences were not statistically significant, although this regularity was visible in both study seasons. Earthworm biomass calculated per 100 samples was higher for random plots (0.348 ± 0.500g; IQR = 0.000-0.482g) than for feeding sites (0.324 ± 0.465g; IQR = 0.000-0,407g), but these differences were not significant. The analysis carried out independently for both study seasons showed slightly different results. In 2013, earthworm biomass was higher in random samples compared to samples collected at feeding places, while in 2014 the opposite was true. However, in both seasons these differences were not statistically significant (M. Sielezniew - unpublished data). These results indicate that in places where the species occur, the other habitat parameters (vegetation structure, soil softness and humidity) have a stronger impact on the selection of feeding sites than the abundance of invertebrates in soil. However, the fact that the abundance of earthworms is relatively low compared to the results from Scandinavia is worrying. The average biomass of earthworms per 1 m2of soil up to a depth of 10 cm at the feeding sites of the great snipe for all samples and for those in which earthworms were found in Poland was 14.40 g and 21.66 g, respectively (N = 188, N = 125, M. Sielezniew - unpublished data), while in Scandinavia it corresponded on average to 40.67 g (Løfaldli et al. 1992). This result suggests a lower quality of the great habitats in terms of abundance in food compared to habitats found in the Scandinavian mountains.