Identification of deep-water pink shrimp abundance distribution patterns and nursery grounds in the eastern Mediterranean by means of generalized additive modelling

Generalized Additive Modelling (GAM) techniques were used to model the time series of abundance data of deep-water pink shrimp, collected during the MEDITS bottom trawl surveys carried out in the Greek seas from 1996 to 2006, as functions of the sampling location (longitude–latitude), depth and year. The life stages of the species were taken into account. All variables were highly significant, although latitude and depth had always the highest explanatory power. The total abundance was higher between 100 and 400 m of depth, with juveniles and adults being more abundant in the 100–200 m and 200–400 m depth strata, respectively. GAM prediction maps showed high abundance concentration areas for all life stages mainly in the Aegean Sea. The most important nursery ground identified was located in the Saronikos Gulf and a secondary in the Thracian Sea. Concerning the concentration areas of the adult specimens, they are located mainly in the Saronikos Gulf, the Thracian Sea, the Thermaikos Gulf, the Cretan Sea and the eastern part of the Aegean. Guest Editor: V. D. Valavanis Essential Fish Habitat Mapping in the Mediterranean     

Distribution of the under-ice mesozooplankton in the Kara Sea in February 2002

Mesozooplankton distribution was investigated under the sea ice in the Kara Sea at five stations in February of 2002 by Juday net hauls. Copepods dominated the mesozooplankton community, accounting for 46–88% of the total abundance and 68–99% of the biomass. Oithona similis was the most abundant species in Yenisei Bay, being present with all age stages (including egg-carrying females). For the first time, Oithona atlantica (CIII–CV copepodites, females and males) were found in the southeastern Kara Sea. In the southern part, Copepoda nauplii prevailed in terms of total abundance while the mesozooplankton in the northwestern part was entirely dominated by older stages of Pseudocalanus minutus. The mesozooplankton structure appears to be determined by available food resources and increased water temperature due to a strong influence of warm Atlantic waters.     

The composition and distribution of pelagic ostracods (Ostracoda: Myodocopa) in antarctic waters adjacent to the d’Urville Sea

The faunistic composition of pelagic ostracods of regions situated to the north and northwest of the d’Urville Sea (60°–65°S, 148°–136° and 136°–113°E) is largely similar to that of the area adjacent to the Somov Sea at the same latitudes. Alacia hettacra is the most abundant species here; Austrinoecia isocheira, Boroecia antipoda, and Obtusoecia antarctica are common species. The maximum abundance of pelagic ostracods is observed in the 100–200 m depth range; the largest contribution to it is contributed by A. hettacra. The number of species increases with increasing depth. The 64°–65°S region between 148° and 113° E is regarded as the northern boundary of the “Polar Antarctic zone.”     

Habitat characteristics of crayfish (<Emphasis Type="Italic">Paranephrops planifrons</Emphasis>) in New Zealand streams using generalised additive models (GAMs)

Quantitative data on the habitat characteristics of stream crayfish have been generally lacking and competing demands on water resources has created a need to address this knowledge gap. We investigated day-time habitat relationships of stream crayfish (Paranephrops planifrons White) from 793 quadrats at 30 rivers and streams in the North Island, New Zealand to develop models of koura presence–absence and abundance. The model (stepwise GAM) included width, cover, median substrate size, edge location, velocity and depth, and correctly predicted presence–absence of crayfish (8–39 mm OCL) at 73.4% of quadrats and of young-of-the-year (YOY) ≤8 mm OCL at 83.4% of quadrats. Streams ranged from 1.6 to 11.5 m in width and the probability of finding both crayfish size classes reduced sharply as streams became wider than 6 m and as the substrate became large (i.e., boulder > 256 mm). Crayfish, particularly YOY, were most likely to be found in association with cover and at the stream edge. YOY were associated with shallow depths and fine substrates, whereas larger crayfish showed a preference for cobble substrate. Undercut banks, leaf litter, tree roots, and woody debris were strongly related to the presence–absence of crayfish. The model for crayfish abundance (log-linear Poisson GAM) explained 50% of the variation between quadrats with cover, velocity, edge location, depth, and the overall crayfish abundance at each particular stream being significant variables. Highest crayfish numbers were recorded in still or slow flowing water, with the majority occurring where velocities were below 0.4 m/s. Water depths up to 0.7 m were sampled, but highest numbers were found in depths of 0.2–0.3 m. Our presence–absence model determined variables that were significant over all streams, whereas our abundance model determined variables that were significant within streams. Use of the GAMs models enabled us to untangle the multiple factors contributing to habitat selection. Cover, velocity, and locations at the stream edge were important determinants of both presence–absence and abundance. Generally, substrate was important when comparing between streams, but not within streams, whereas depth was a significant determinant of abundance within streams, but not presence–absence between streams. Handling editor: K. Martens     

Chinese mitten crab <Emphasis Type="Italic">Eriocheir sinensis</Emphasis> in the Baltic Sea—a supply-side invader?

Although the Chinese mitten crab Eriocheir sinensis (H. Milne-Edwards, 1853) (Crustacea, Decapoda, Varunidae) invaded the Baltic Sea about 80 years ago, published information on its present distribution and abundance in this region is lacking. We provide here information on its Baltic-wide distribution and long-term population dynamics. The species has been found all over the coastal Baltic Sea and also in some adjacent rivers and lakes. The Chinese mitten crab appears to have increased in abundance in recent years in the northeastern part of the Baltic Sea (Gulf of Finland, Gulf of Riga, northern Baltic Proper). Higher catch rates were observed in spring (April–June) and autumn (September–November). The size variation of crabs in different samples was low (mean carapace width 6.1–6.3 cm). Despite findings of gravid females, the reproduction of the mitten crab in the central, northern and eastern Baltic region is considered unlikely due to low salinity and the individuals caught are assumed to actively migrate into the region from the species’ main European distribution area (southeastern North Sea), certainly over 1500 km migration distance. Thus, the dynamics of the North Sea population is probably regulating, at least in part, the occurrence of the Chinese mitten crab in the Baltic Sea area.     

Vertical distribution and abundance of juvenile chaetognaths in the Weddell Sea (Antarctica)

The composition, abundance and vertical distribution of chaetognaths were analysed along a transect in the Weddell Sea during late spring. Three species were identified: Eukrohnia hamata (90.8%), Sagitta marri (6.4%) and S. gazellae (2.8%). Only juvenile stages were collected in the samples, a result related both to the type of sampling gear employed (mesh size: 100 μm) and the species' life-cycles. The vertical distributions showed that the juvenile stages of these species tended to aggregate at considerable depth (1000–500 m). It is postulated that this pattern may be related to the life-cycles of these species in association with seasonal Antarctic conditions, similar to the pattern postulated for krill and other polar crustaceans. Accepted: 10 July 2000     

Macroalgal blooms and species diversity in the Transition Zone of the eastern Gulf of Finland

The Macroalgal flora of the Transition Zone of the eastern part of the Gulf of Finland was studied between 2003 and 2008. Sixteen species were found from a depth of 0.5–5 m. Three species (Cladophora aegagropila, Pseudolithoderma subextensum and Hildenbrandtia rubra) are listed as rare in The Red Data Book of Nature of the Leningrad Region (Tzvelev, 2000). Nine species are recorded here for the first time in Transition Zone of eastern Gulf of Finland. The dominant species growing at a 0.5–1.5 m depth was the green alga Cladophora glomerata. Our study shows that in 2003–2008 in the shallow (0.5–1.5 m) zone of the eastern Gulf of Finland, the biomass of C. glomerata peaks several times in a season reaching 450 ± 130 g DW m⁻². Our study corrects earlier data for the species composition of macroalgae and describes their depth and horizontal distribution in the Gulf of Finland.     

Systematic review of the genus <Emphasis Type="Italic">Bothrocara</Emphasis> Bean 1890 (Teleostei: Zoarcidae)

The systematics of the eelpout genus Bothrocara Bean 1890 is reviewed on the basis of 941 specimens. Eight mostly eurybathic, demersal species are recognized, distributed mainly along the continental slopes of the North and South Pacific oceans, with one species entering the South Atlantic. Distributions are: B. brunneum ranges from the Sea of Okhotsk to the Gulf of Panama at depths of 199–1,829 m; B. elongatum ranges from the Gulf of Panama to Chile at depths of 720–1,866 m; B. hollandi ranges from the Sea of Japan to the southeastern Bering Sea at depths of 150–1,980 m; B. molle ranges from the western Bering Sea to the South Atlantic at depths of 106–2,688 m; B. nyx is known only from the eastern Bering Sea at depths of 790–1,508 m; B. pusillum ranges from the northern Bering Sea to British Columbia, Canada, at depths of 55–642 m; B. tanakae is found along the northern coasts of Honshu and Hokkaido islands, Japan, at depths of 274–892 m; B. zestum ranges from the Izu Islands, Japan, and central Honshu, Japan, to the Gulf of Alaska at depths of 199–1,620 m (an unidentifiable specimen from off Taiwan may be B. zestum). The species are distinguished from one another mainly on the basis of head pore patterns, gill raker morphology, coloration and various meristic and morphometric values. A determination key to the species is provided.     

Summer mesozooplankton distribution near Novaya Zemlya (eastern Barents Sea)

Regional variations in mesozooplankton composition, abundance and biomass were studied during a cruise in August 2006 near Novaya Zemlya Archipelago (eastern Barents Sea) using Juday net hauls from the bottom (or 100 m depth) to the surface. A comparison with multiannual literature values revealed that the mean temperature and salinity in the south and centre of the study area were similar to typical values, while temperature in the north was significantly higher. A total of 36 species and higher taxa were identified. Mesozooplankton abundance and biomass varied from 47 to 851 ind m⁻³ and from 5 to 74 mg dry weight m⁻³, respectively. Copepods dominated the mesozooplankton community, reaching 73–98% and 61–97% of the total abundance and biomass. Calanus finmarchicus and Oithona similis were the most abundant species at all stations. The biodiversities (Shannon indices) of the mesozooplankton community varied between stations from 1.10 to 2.46 (estimated from species abundances) and from 0.19 to 1.92 (estimated from species biomasses), averaging 1.93 ± 0.127 and 1.34 ± 0.151, respectively. Three groups at the 48% level of dissimilarity of species abundance were delineated by cluster analyses. The clusters differed significantly with respect to temperature and salinity. The total mesozooplankton abundance and biomass as well as quantitative parameters of most common taxa scaled negatively with temperature.     

Geographic, seasonal and bathymetric distribution of demersal fish species in the eastern Mediterranean

The distributional abundance of three demersal fish species, Merluccius merluccius, Mullus barbatus and Lophius budegassa, was studied as a function of sampling season, bathymetry and geographic area. Data were collected during research trawl surveys in the Aegean and Ionian seas under the same sampling scheme, thereby allowing comparisons to be made on the mean regional densities in numbers and biomass of these three commercially important species in Greek waters. Results indicated that European hake, M. merluccius, demonstrated a wide bathymetric and geographic distribution, with specimens encountered in all regions between 20 and 500 m depth, although density was found to be highest usually between 101 and 200 m. The mean regional density of hake was observed to vary seasonally, being higher mainly in winter. Red mullet, M. barbatus, was distributed in shallow water depths (<100 m) throughout the Greek seas, particularly in the northern part of the Aegean Sea. Abundance of this species steadily decreased with increasing depth. The geographic distribution of anglerfish, L. budegassa, was found to be restricted to the central and northern part of the Aegean Sea, with the highest mean densities encountered in the Thermaikos Gulf and in intermediate water depths between 101 and 200 m. Spatial patterns of observed density are assumed to be attributed mainly to prevailing topographic and hydrographic conditions and related biological productivity levels.     

The importance of small scales to the fruit-feeding butterfly assemblages in a fragmented landscape

Nowadays 37% of Earth’s ice-free land is composed by fragments of natural habitats settled in anthropogenic biomes. Therefore, we have to improve our knowledge about distribution of organisms in remnants and to understand how the matrix affects these distributions. In this way, the present study aims to describe the structure of the butterfly assemblages and determined how richness and abundance are influenced by the scale of the surrounding vegetation. General linear models were used to investigate how the type and scale of vegetation cover within a radius of 100–2,000 m around the sampling point explained butterfly diversity. After sampling ten forest fragments we found 6,488 individuals of 73 species. For all clades tested null models explain the species richness at the fragments better than other models when we include the effect of butterfly abundance as a covariate. Abundance of Satyrini, Brassolini, and Biblidinae were best predicted by small scales (100–200 m), and large scales were more suited for Charaxinae. The presence of pasture best explains the abundance of all groups except Charaxinae, which was best explained by early-regrowth forest. The abundance of different species and groups are correlated with different kinds of vegetation cover. However, we demonstrate that small scales (100–200 m) are more effective at explaining the abundance of most butterflies. These results strongly suggest that efforts to preserve insect diversity in forest fragments should take in account the immediate surroundings of the fragment, and not only the regional landscape as a whole. In general, actions of people living near forest fragments are as important to fruit-feeding butterflies as large scale actions are, with the former being seldom specified in management plans or conservation policies.     

Distribution and ecology of the tintinnids in the Gulf of Elat (Aqaba), Red Sea

The tintinnids were studied as part of a microplankton investigationin the Gulf of Elat (Aqaba) (Red Sea) based on stratified samplescollected at a reference station over a period of one year (1974–75).The results of this study were compared to the data obtainedfrom the same area in the course of a previous survey (1970–71). The ranges of abundance of the tintinnids as a whole and ofthe leading species of this group were determined from 0–50m, 50–100 m and thereafter at intervals of 100 m downto a depth of 600 m for the samples collected during 1974–75.For those collected during 1970–71, the ranges of abundancewere determined at two depths in vertical profiles over thewater column from 50 and 200 m to the surface. Two distinct peaks were noted, one in November-December anda second in February-March. A third minor peak occurred duringJune-July. The main winter peak of February-March occurred duringthe turnover period characterized by two uniform temperaturesof 21°C or less throughout the water column. The seasonaland spatial distribution of the tintinnids closely followedthat of the main phytoplankton groups, with greatest abundancerecorded in the upper 100 m. The species composition of the tintinnids during the annualpeaks changed from season to season and from year to year. However,8 species of a total of 42 recorded during the investigationwere responsible for the annual peaks during both years. Amongthe environmental parameters monitored during the 1974–75survey only the temperature factor could be related to the distributionpattern of one of the 8 leading species of tintinnids. A summer submergence to deeper levels has been noted in regardto some of the prevailing species.     

Basin scale distribution of zooplankton in the Ligurian Sea (north-western Mediterranean) in late autumn

Mesozooplankton biomass and abundance were evaluated in epipelagic waters at 59 stations covering the Italian sector of the Ligurian Sea (north-western Mediterranean) in December 1990. This region is characterised by a cyclonic circulation which encloses a central divergence zone and is associated with a main thermohaline front offshore the western Ligurian coast. At the end of autumn, mesozooplankton biomass (range: 0.80–4.24 mg DW m⁻³) and the abundance (range: 83.8–932 ind. m⁻³) were lower in the divergence zone. On the contrary, in the Ligurian frontal zone at the periphery of the divergence and on the eastern continental shelf the greatest values of biomass and abundance were recorded. Copepods and appendicularians dominated the mesozooplankton community, the main taxa being the copepods Clausocalanus spp. (46% of total zooplankton) and Oithona spp. (15%) and the appendicularian Fritillaria spp. (12%). Three hydrological sub-regions, i.e. the divergence, the eastern continental shelf and the periphery of the divergence, were characterised by different zooplankton communities and characteristic species. Environmental differences between the three zones were mainly related to changes in bottom topography, sea surface temperatures and quantity of particulate organic matter. Vertical mesozooplankton abundance and taxa distribution from the surface to 1,900 m depth were also examined in one station. The results showed that the bulk of the community was concentrated in the upper 200 m, small copepods being dominant particularly in the upper 50 m. The copepod community was more diversified in sub-superficial waters, with a maximum observed in the 200–400 m layer. The distributions of main zooplankton taxa described in epipelagic waters in the eastern Ligurian Sea in autumn were compared with their distribution at surface in the north-western Mediterranean obtained by sampling performed with the Continuous Plankton Recorder in 1997–1999. The analysis of the zooplankton community in CPR samples confirms the dominance of small copepods (Paracalanus spp., Clausocalanus spp., Oithona spp.) and appendicularians in the north-western Mediterranean in late autumn-winter and shows that their distribution is mainly related to the main mesoscale hydrographic features characterising this basin. Guest editors: S. Souissi & G. A. Boxshall Copepoda in the Mediterranean: Papers from the 9th International Conference on Copepoda, Hammamet, Tunisia     

Distribution of capsulated bacterioplankton in the North Atlantic and North Sea

In laboratory experiments, bacterioplankton were incubated under different nutrient conditions, and the percentage of bacteria exhibiting a polysaccharidic capsule (capsulated bacteria) and that of CTC (cyanotetrazolium chloride)-positive and therefore metabolically highly active bacteria were determined. In these seawater cultures amended with nutrients more than 95% of the CTC-positive cells exhibited a capsule. During two cruises, one to the North Atlantic and one to the North Sea, we investigated the distribution of capsulated bacteria throughout the water column. Capsulated bacteria were generally more abundant in eutrophic surface waters than in deeper layers or more oligotrophic regions. In the upper 100 m of the North Atlantic, about 6–14% of the total bacterioplankton community was capsulated, while in the layers below 100 m depth, 97% of the bacteria lacked a visible capsule. The percentage of capsulated bacteria correlated with bacterial abundance and production, and chlorophyll a concentration. Also, the bioavailability of DOC (dissolved organic carbon), estimated by the ratio between bacterial production and DOC concentration, significantly correlated with the percentage of capsulated bacteria. In the North Sea, the contribution of capsulated bacteria to the total number of bacteria decreased from the surface (3 m depth) to the near-bottom (25–35 m) layers from 20% to 14% capsulated bacteria. In the nearshore area of the North Sea, about 27% of the bacteria exhibited a capsule. Overall, a pronounced decrease in the contribution of capsulated bacteria to the total bacterial abundance was detectable from the eutrophic coastal environment to the open North Atlantic. Using this epifluorescence-based technique to enumerate capsulated bacterioplankton thus allowed us to routinely assess the number of capsulated bacteria even in the oceanic water column. Based on the data obtained in this study we conclude that almost all metabolically highly active bacteria exhibit a capsule, but also some of the metabolically less active cells express a polysaccharide capsule detectable with this method.     

Composition and distribution of pelagic ostracods (Ostracoda: Myodocopa) in the Somov and Ross seas and adjacent waters of the Southern Ocean

The study of materials collected by Russian expeditions and literature data showed that the pelagic ostracod fauna of the Somov Sea, which lies south of the Antarctic Divergence (AD), is an impoverished complex of the fauna of the Australian-New Zealand Antarctic sector. While to the north of the AD the ostracod fauna includes species introduced from waters of the subantarctic and tropical-subtropical structures, ostracods of the Somov Sea are mainly typical Antarctic species. To the north and south of the AD, ostracod abundance and species richness are highest in the depth range of 200–500 m (especially at 300–400 m). Austrinoecia isocheira is the most common species in the Somov Sea and Alacia hettacra in the adjacent northern region. The more southerly Ross Sea has harsher environmental conditions than the Somov Sea and its ostracod fauna is a more impoverished complex of mainly Antarctic species. Alacia belgicae and A. isocheira are the dominant species in the Ross Sea, with their highest abundances at 200–300 m depths. The proportion of A. hettacra in the Ross Sea taxocene decreases southwards. The taxonomical composition and biogeographical structure of ostracod faunas change in the AD region at the northern boundaries of both seas.     

Cobbles colonization pattern from a tsunami-affected coastal area (SW Thailand,Andaman Sea)

We studied the sclerobiont community associated with organogenic and lithic cobbles from soft bottoms in the Khao Lak coastal area (Andaman Sea) that was damaged by the 2004 tsunami. The 15 cobbles examined originate from grab and hand sampling carried out in the years 2006 and 2007 in the depth range of 4.6–15.2 m. A rich endo- and epibenthos was identified, mainly consisting of algae, foraminifers, sponges, cnidarians, polychaetes, bryozoans and bivalves. Associations on each examined cobble show similarities in composition and structure being characterized by a few dominant groups. Differences were noted in the degree and pattern of colonization, distinguishing for each cobble an upward and a downward side at the time of sampling. The mean total coverage is 15.09% being higher on the upper sides (17.4%) compared to the lower sides (12.8%). Calcareous algae, bivalves and sponges prevail on upper sides, while bryozoans prevail on lower sides. The sclerobionts distribution allowed to infer the orientation of cobbles on the seafloor during colonization. Major colonization values, exceeding 30% coverage, were observed on organogenic cobbles located in the proximity of reefs or collected from below 12 m of water depth. Conversely, cobbles from the shallowest stations result poorly colonized, independently of their composition. The water turbidity and wave motion as a possible cause of the observed distributions were discussed. The Khao Lak cobble community seems to be largely unaffected by the tsunami event, as suggested by the estimated biodiversity, abundance and coverage of sclerobionts.     

Macrobenthic fauna of the Franz Josef Land archipelago

Benthic fauna of the deeper waters (50–320 m) of the Franz Josef Land archipelago sampled in August 1992 using standard western techniques is described and compared with earlier Russian studies of the archipelago. Three faunal assemblages are recognised at depth ranges between 50–150, 150–300, and >300 m depth. Their distributions are related to depth and to different water masses derived from a mixture of Barents Sea water entering from the south at intermediate depths (20–150 m), and Atlantic water from the north below 300 m. The recorded faunal diversity and biomass is as high as or higher than that from comparable Arctic and northern boreal areas. Comparisons are also made with a complimentary Russian survey in the same area using different techniques. The Russian work collected larger organisms most effectively, whereas the present work recorded the smaller taxa more efficiently. Russian surveys provide complementary data to western studies, but care must be taken when comparing studies as they reflect biases in sampling gear and scientific emphasis. These data intercalibrations are important as Russian archives contain a wealth of information that, if used correctly in association with western data sources, will be useful in environmental monitoring studies as human activities increase in the Eurasian Arctic. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Population genetic structure and evolutionary history of North Atlantic beluga whales (Delphinapterus leucas) from West Greenland, Svalbard and the White Sea

Population structure in many Arctic marine mammal species reflects a dynamic interplay between physical isolating mechanisms and the extent to which dispersal opportunities are met. We examined variation within mtDNA and eight microsatellite markers to investigate population structure and demographic history in beluga whales in the North Atlantic. Genetic heterogeneity was observed between Svalbard and West Greenland that reveals limited gene flow over ecological time scales. Differentiation was also recorded between Atlantic belugas and two previously studied populations in the North Pacific, the Beaufort Sea and Gulf of Alaska. However, Bayesian cluster analysis of the nDNA data identified two population clusters that did not correspond to the respective ocean basins, as predicted, but to: (1) Arctic (Svalbard–White Sea–Greenland–Beaufort Sea) and (2) Subarctic (Gulf of Alaska) regions. Similarly, the deepest phylogeographic signal was between the Arctic populations and the Gulf of Alaska. Fitting an isolation-with-migration model yielded genetic abundance estimates that match census estimates and revealed that Svalbard and the Beaufort Sea likely diverged 7,600–35,400 years ago but have experienced recurrent periods with gene flow since then, most likely via the Russian Arctic during subsequent warm periods. Considering current projections of continued sea ice losses in the Arctic, this study identified likely routes of future contact among extant beluga populations, and other mobile marine species, which have implications for genetic introgression, health, ecology and behavior.     

Distribution,abundance, and food habits of the snailfishLiparis tanakai in the Suo Sea,Seto Inland Sea

In order to examine the distribution, abundance, and food habits of the snailfish,Liparis tanakai, in the Suo Sea, western Seto Inland Sea of Japan, experimental fishing surveys were made using trawl nets on the night (1930–0340 h) of 26 May and 2 and 3 June, 1986. The study area was subdivided into 18 areas, each sampled by one trawl tow of 35 min duration. A total of 190 fish was collected during the surveys, and most fish (78.9%) were obtained from muddy substrata ranging in depth from 30 to 40 m at the middle area of the Suo Sea. The total length of the fish in the samples ranged from 72 to 273 mm. The overall length-frequency distribution formed a unimodal curve, the mode occurring at the class of 100–130 mm in total length. Of 151 fish examined, 146 (96.7%) had stomachs full of food, including a variety of small crustaceans and fish. Shrimps, especiallyCrangon affinis, ranked highest in importance in the diet ofL. tanakai. These biological data are compared with those of conspecifics from Sendai Bay, northern Honshu of Japan.     

Assessment of the Neva Estuary ecosystem state on the basis of structural characteristics of benthic animal communities in 1994–2005

In the years 1994–2005, the values of the integrated index IP’ at some stations of the Neva Bay changed from 38.1 to 81.9%, water quality changed from class 3 to class 5, and the states of some areas of the ecosystem that were evaluated as “tense” went to “catastrophic.” The integrated mean assessment of water quality according to the IP’ index over the entire Neva Bay throughout 12 years (1994–2005) remained relatively stable, waters were assessed as “polluted” (fourth class), and the state of the ecosystem was considered “critical.” The state of the eastern part of the Gulf of Finland in 1994–2005 was less favorable. The species diversity of zoobenthos in the resort zone of the eastern part of the Gulf of Finland is considerably lower than in the Neva Bay. Waters of the resort zone of the eastern part of the Gulf of Finland in 1994–2005 were assessed as one class lower than in the Neva Bay, i.e., as “polluted-dirty” (fourth-fifth class), and the state of the ecosystem was assessed as being in a “crisis.” In the resort zone, there was a decline in species diversity and abundance and biomass of benthic animals; i.e., all characteristics of the degradation of benthic animal communities were observed.