During the investigation of parasitic pathogens of Mytilus coruscus, infection of a Perkinsus-like protozoan parasite was detected by alternative Ray's Fluid Thioglycolate Medium (ARFTM). The diameter of hypnospores or prezoosporangia was 8–27 (15.6 ± 4.0, n = 111) μm. The prevalence of the Perkinsus-like species in M. coruscus was 25 and 12.5% using ARFTM and PCR, respectively. The ITS1-5.8S-ITS2 fragments amplified by PCR assay had 100% homology to that of P. beihaiensis, suggesting that the protozoan parasite was P. beihaisensis and M. coruscus was its new host in East China Sea (ECS). Histological analysis showed the presence of trophozoites of P. beihaiensis in gill, mantle and visceral mass, and the schizonts only found in visceral mass. Perkinsus beihaiensis infection led to inflammatory reaction of hemocyte and the destruction of digestive tubules in visceral mass, which had negative effect on health of the farmed M. coruscus and it deserves more attention.

Two new species of free-living marine nematode discovered from an intertidal sandy beach in the Bohai Sea and from a sublittoral region in the East China Sea are described. Deontolaimus holovachovi sp. nov. is characterized by short cephalic setae (2.5–3 μm long); ventrally-unispiral amphidial fovea; excretory pore located at the level with nerve ring; lateral alae present; two pairs of lateral cervical setae present; arcuate spicules 1.5–1.6 cloacal body diameter long, with the proximal half swollen and proximal end hooked, the distal half narrow; gubernaculum with dorso-caudal apophysis; postcloacal sensilla present in males; a midventral caudal papilla with a short seta situated at posterior third of tail length. Campylaimus zhoui sp. nov. is characterized by loop-shaped amphid with very long ventral limb extending along pharyngeal region to level of anterior part of intestine, 4.7–5.2 times the length of dorsal limb; excretory pore opening posterior to the pharyngo-intestinal junction; spicules symmetrical, slightly arcuate without proximal capitulum; gubernaculum with small dorsal apophysis; precloacal supplements absent.

Much has been made over the past few years of China'vs ambitions of regaining control of its irredentist claims in the East and South China Seas. While some of this speculation focuses on the massive amounts of money the People's Republic of China (PRC) has funneled into its naval modernization program, other analysts are more interested in the drivers behind the increasingly popular sentiment that the country must “reclaim” its lost territories. The Chinese Communist Party can ill afford to ignore the voice of an already disenchanted population if it hopes to stay in power, particularly in regard to matters of national pride. As a result, in dealing with China's irredentist claims, nationalism in particular can be a powerful ideological factor in shaping the nation's foreign policies. This is especially apparent in the case of irredentism, where nationalism can often override diplomatic and strategic imperatives. This paper addresses the question of how does the nationalist discourse vary between two territorial disputes, the East and South China Seas. It uses discourse analysis to examine developing trends among online social media and news sites. This in turn allows for the construction of a framework of how nationalism develops among both elite and grassroots audiences.

What are the consequences of nationalist unrest? This paper utilizes two original datasets, which cover 377 city-level anti-Japanese protests during the 2012 Senkaku/Diaoyu Island crisis and the careers of municipal leaders, to analyse the downstream effects of nationalist unrest at the subnational level. We find both political and economic consequences of China's 2012 protest demonstrations against Japan. Specifically, top Party leaders in cities that saw relatively spontaneous, early protests were less likely to be promoted to higher office, a finding that is consistent with the widely held but rarely tested expectation that social instability is punished in the Chinese Communist Party's cadre evaluation system. We also see a negative effect of nationalist protest on foreign direct investment (FDI) growth at the city level. However, the lower promotion rates associated with relatively spontaneous protests appear to arise through political rather than economic channels. By taking into account data on social unrest in addition to economic performance, these results add to existing evidence that systematic evaluation of leaders’ performance plays a major role in the Chinese political system. These findings also illuminate the dilemma that local leaders face in managing popular nationalism amid shifting national priorities.

This article presents a modified method for extraction of dissolved inorganic carbon (DIC) from seawater for radiocarbon measurement by accelerator mass spectrometry (AMS). Standard tests indicate that the extraction efficiencies of DIC are >96%, and the respective precisions of Δ14C-DIC and δ13C-DIC analyses are 6‰ and 0.1‰ or better. Using the method, we report Δ14C-DIC profiles collected from the shelf and slope in the East China Sea (ECS) of the northwest Pacific Ocean. Both the DIC concentration and Δ14C-DIC in the shelf and slope regions seem primarily affected by the Kuroshio Current. It is estimated that 54–65% of the bottom water in the shelf region could be from the intrusion of Kuroshio intermediate water, which carries a high concentration and low Δ14C values of DIC, and which influenced the DIC and its 14C signature on the shelf. Compared with the Δ14C-DIC profiles at other sites in the northwest Pacific reported previously, it appears that the Δ14C-DIC distributions are mainly controlled by the major oceanic currents in the region, and large variations in Δ14C-DIC occurred mostly in the upper 800 m of the water column. The similarity of Δ14C-DIC at depth suggests that the deep-water circulation patterns have been relatively stable in the northwest Pacific Ocean in the last 20 yr.

Why do some Chinese cities take part in waves of nationalist protest but not others? Nationalist protest remains an important but understudied topic within the study of contentious politics in China, particularly at the subnational level. Relative to other protests, nationalist mobilization is more clustered in time and geographically widespread, uniting citizens in different cities against a common target. Although the literature has debated the degree of state-led and grassroots influence on Chinese nationalism, we argue that it is important to consider both the propensity of citizens to mobilize and local government fears of instability. Analysing an original dataset of 377 anti-Japanese protests across 208 of 287 Chinese prefectural cities, we find that both state-led patriotism and the availability of collective action resources were positively associated with nationalist protest, particularly “biographically available” populations of students and migrants. In addition, the government's role was not monolithically facilitative. Fears of social unrest shaped the local political opportunity structure, with anti-Japanese protests less likely in cities with larger populations of unemployed college graduates and ethnic minorities and more likely in cities with established leaders.

The chub mackerel (Scomber japonicus) has been one of the important commercial pelagic species in the East China Sea since the decline of traditional demersal economic species. Although chub mackerel resources are suffering over-exploitation with the increase of fishing effort, their response to fishing and changing trends have not been analysed because of a shortage of data. In this paper we separated sample catches of chub mackerel from the central East China Sea during 2009 and 2010 into three age groups based on the age–fork length key. We then estimated the maximum sustainable yield (MSY) and built a spawner–recruitment relationship based on the fishery statistics of purse seine vessels, lighting purse seine vessels and deep-water purse seine vessels from 2006 to 2012. We predicted the biomass, spawning biomass, catches and the length compositions of catches when fishing at the current intensity (fishing mortality (F) = 0.7). The results showed that the MSY of chub mackerel is about 18.8 × 104t, and the fishing effort at MSY (EMSY) is about 72 standard purse seine vessels (both the lighting purse seine vessels and deep-water purse seine vessels were standardized to purse seine vessels), which is equivalent to F = 0.4. If F remains at the current level, the biomass of chub mackerel will remain at 45.3 × 104t. At the same time, more than 40% in the catch will be the individuals smaller than 200 mm, and only about 8% will be larger than 300 mm. Therefore, there is little potential for further exploitation of the chub mackerel resources in the central East China Sea, and it is better to reduce F to less than 0.4 for sustainable utilization.

Two species of Farranula, including a new species, are described from off Jeju Island, Korea (East China Sea). Farranula orbisa sp. nov. can be distinguished from its congeners F. curta (Farran, 1911) and F. rostrata (Claus, 1863) by a combination of morphological characteristics as follows: in females, (1) eyes located on the frontal part of prosome adhered to each other, (2) second urosomal somite distinctly rounded from the anterior to mid-region in lateral and dorsal view, (3) second urosomal somite ornamented with fine spinules on anteroventral margin; in males, (4) sharply contracted portion of second somite located at two-thirds distance from anterior margin, (5) caudal rami relatively longer compared to width at its base. The new species F. orbisa was erroneously identified as F. rostrata (Claus, 1863) from the East China Sea and as F. curta (Farran, 1911) from the Indian Ocean. The poorly described F. carinata (Giesbrecht, 1891) from the East China Sea is redescribed here based on both sexes of specimens and compared to its morphological variability with specimens from other regions.

A record body size, length of 1520 mm and weight of 12,600 g for the beach conger, Conger japonicus was recorded, which is approximately 120 mm and 2600 g larger than the previous international record. The specimen was female and obtained during an otter trawl survey on 4 April 2013 in the East China Sea (31°52.16′N 127°42.94′E) at a depth of approximately 140 m on the slope of the continental shelf. Morphometric measurements and meristic counts are reported in this paper. We also report profiles of water temperature, salinity, dissolved oxygen and chlorophyll-a taken immediately prior to the trawl, and species composition of concurrent catch with the otter trawling as environmental and biological characteristics of the habitat.

Determining optimal temperature and salinity for marine organisms is a challenge for marine ecologists because not every species can be easily maintained in the laboratory for testing the influence of environmental parameters. To find a simple method to estimate the optimal temperature and salinity for marine organisms based on survey data, a reciprocal quadratic yield-density model was used for determining the optimal temperature or salinity from abundance data for six pelagic Chaetognatha species. The data for the modelling were collected in four surveys in the East China Sea (23°30′–33°N 118°30′–128°E) from 1997 to 2000. According to both survey data and results from the models, we analysed qualitatively and quantitatively the ecological characteristics of those species. Estimated optimal temperatures and salinities are 17.3°C and 14.1‰ for Sagitta nagae, 20.3°C and 13.8‰ for S. bedoti, 24.9°C and 32.9‰ for S. enflata, 22.5°C and 16.5‰ for S. ferox, 24.5°C and 34.1‰ for S. pacifica and 17.3°C and 14.1‰ for S. pulchra, respectively. Three ecological groups were evident in the East China Sea: the neritic, warm temperate water species (S. nagae); the neritic, warm water species (S. pulchra, S. ferox and S. bedoti); and the oceanic, warm water species (S. enflata and S. pacifica). Our results validate that the model is applicable for describing the relationship between chaetognaths abundance and temperature or salinity.

A total of twenty-seven species of marine-living coccolithophores were recorded from seawater samples that were collected during two spring cruises along the shelf regions of the Yellow Sea (YS) and the East China Sea (ECS). They were classified into ten families and four orders, with some additional species incertae sedis. Most of these species were heterococcolithophores, and no holococcolithophores were examined from the YS waters. Six species were recorded for the first time from the coastal waters of the China Seas and their morphological characteristics are described and photographically illustrated in this paper. They were Cyrtosphaera lecaliae, Syracosphaera histrica, Syracosphaera marginaporata, Pappomonas cf. sp. type 3, Calyptrolithophora papillifera and Corisphaera strigilis. Three types of Emiliania huxleyi, type A, type B/C and type C, were examined. Species of the genus Syracosphaera, in addition to E. huxleyi and Gephyrocapsa oceanica, frequently occurred at the surveyed sites. The coccolithophore assemblages in the offshore waters of the ECS were characterized by high species diversity—fourteen species in one sample. This finding indicated that the shelf waters adjacent to the Kuroshio path were ideal habitats for living coccolithophores. The variation in taxonomic composition of these algae could be associated with differences in their preferred habitats.

The East China Sea (ECS) supports a highly productive fishery and is rich in biodiversity, but economic development in China and peripheral countries has led to intensifying anthropogenic impacts in the ECS. In response to this the Chinese government has introduced a range of marine spatial management measures. A spatial ecosystem model (Ecospace) of the ECS was developed to examine (1) the likely nature of trade-offs between fishery and conservation goals resulting from the marine protected areas (MPAs) and (2) possible trade-offs within the fishery sector resulting from the MPAs. The results suggest that overall the fishery has benefited from all of the simulated MPAs, whereas, although they defy categorical interpretation, effects of the MPAs on biodiversity and ecosystem structure are variable. Simultaneous application of several metrics of ecosystem status indicates that the perceived effect of an MPA on ecosystem status can depend on which metrics for ecosystem status are used, and how these metrics are interpreted. The simulations indicate that a fisheries and conservation outcome beneficial to all is possible, but not guaranteed, with the creation of an MPA. Total landings and profitability are predicted to have increased as a result of each of the MPAs, albeit at the cost of reduced landings and profits to some sectors of the fishery. This study demonstrates the benefits of the additional information relating to biodiversity, ecosystem structure and within fishery dynamics available from spatial ecosystem models compared to the single species models typically used to examine MPA effects. However, the use of a more complex ecosystem model introduces additional uncertainty in model interpretation.