Comparison of energetic fl ow through bottom communities (on the example of polychaete populations) in the shallow bights the Chaun Bay (East Arctic) and the Fjord Nella (East Antarctic) located in high latitudes of opposite hemispheres of the planet is carried out for the fi rst time. Polychaete worms abundantly and diversely represented in the bottom biocenosis and playing an important role in their life are one of the most suitable for this kind of analysis of the group. The material is collected and processed by common methods. It turned out that the average values of biomass and assimilation are comparable, although their indices are somewhat higher in Chaun Bay than in Nella Fjord, so the mean values of the current energy are 56 ± 25 and 40 ± 13 kcal / m2 per year, respectively. In this case, such similarity is mainly due to the duration of the light time due to the location of the bays on similar geographical latitudes. In both cases, it was noted that at lower depths, lower values of the energy fl ux are inherent in different sections of the gulf, due to freshening and abrasion of the ice, and higher — at great depths, where the conditions are more stable. It has been established that in the Chaun Bay the share of the biomass of suspension feeders is higher on hard bottom in the macrophyte belt, and on the muds occupying the largest areas of the bottom, deposit feeders predominate. In the Nella Fjord, on the contrary, large areas of the bottom are represented by hard substratum and are occupied, respectively, prevalence of suspension feeders, whereas non-large areas with a slight glossiness are used for life in small forms of infauna and which, according to the type of food, refer to deposit feeders. One of the distinguishing features of the assimilation in the considered bays is the tendency of its growth with depth in the Chaun Bay and its relative constancy in the Nella Fjord; the other is the achievement of relatively high values of the energy fl ux in some parts of the shallow Arctic compared with Antarctica. The differences are apparently explained by the complexity and variability of the water regime in the Chaun Bay and by the greater silting of the bottom, compared to the relatively constant natural conditions of the Nella Fjord, which together determine the features of the functioning of populations of polychaetes, as well as other groups of inhabitants.

The bioenergetic characteristics of bottom communities in the shallow bays of the Arctic and Antarctic have both differences and similarities, and, on the whole, depend on the physico-chemical originality of the areas.