Historical Connectivity and Demography of the Ferocious Reef Crab, Eriphia ferox (Crustacea; Eriphiidae), Demonstrate That Taoyuan Algal Reef Is an Essential Population Source Along the East Taiwan Strait

The east Taiwan Strait is largely fringed by sandy and muddy habitats. However, a massive algal reef made of crustose coralline algae has been found along the coast off Taoyuan city in northwestern Taiwan. The porous structure of Taoyuan Algal Reef harbors high abundance and diversity in marine organisms, including the ferocious reef crab, Eriphia ferox. Such a pivotal geographic location and unique ecological features make Taoyuan Algal Reef a potential stepping stone connecting biotic reefs in the east Taiwan Strait, South China Sea to the south, and even the high latitude of Japan to the north. In this study, we examined the population connectivity and historical demography of E. ferox by analyzing mitochondrial cytochrome oxidase I (COI) fragments of 317 individuals sampled from 21 localities in the northwestern Pacific. Our analyses of haplotype network and pairwise FST comparisons revealed a lack of phylogeographical structure among E. ferox populations, implying the existence of a migration corridor connecting the South and East China Seas through the east Taiwan Strait. Multiple lines of evidence, including significant values in neutrality tests, unimodally shaped mismatch distributions, and Bayesian skyline plots elucidated the rapid population growth of E. ferox following the sea-level rise after Last Glacial Maximum (ca. 2–10 Ka). Such demographic expansion in E. ferox coincided with the time when Taoyuan Algal Reef started to build up around 7,500 years ago. Coalescent migration analyses further indicated that the large and continuous E. ferox population exclusively found in Datan Algal Reef, the heart of Taoyuan Algal Reef, was a source population exporting migrants both northward and southward to the adjacent populations. The bidirectional gene flow should be attributed to larval dispersal by ocean currents and secondary contact due to historical population expansion. Instead of serving as a stepping stone, our results support that Taoyuan Algal Reef is an essential population source for biotic reef-associated species along the east Taiwan Strait, and highlight the importance of conserving such a unique ecosystem currently threatened by anthropogenic development.

Potential Effect of the Intrusion of the Kuroshio Current into the South China Sea on Catches of Japanese Eel (Anguilla Japonica) in the South China Sea and Taiwan Strait

This study examined the effect of the intrusion of the Kuroshio Current (KC) into the South China Sea (SCS) and the Taiwan Strait (TS) (SCS–TS region) on changes in catches of larval A. japonica in the traditional fishing ground waters of Gaoping near southwestern Taiwan in the SCS–TS region. First, the oceanic environment and recruitment trends from 1967 to 2019 were investigated based on secondary data. Then, field surveys were conducted to obtain primary data regarding the intrusion of the KC into the SCS, as well as the changes in the fishing sites and catches of A. japonica in the fall and winter of 2014–2015. Hence, the association between oceanic conditions and the number of A. japonica migrating into the SCS–TS region was explored. From 1967 to 2019, the recruitment proportion in the fishing grounds that formed due to the Kuroshio Branch Current (PKSBC) fluctuated significantly. Overall, positive values were observed for the Oceanic Niño Index for each year with a PKSBC > 50%, corresponding to El Niño conditions. In each year with a PKSBC > 70%, a looping path and a warm–core eddy appeared.

Modeling the Habitat Distribution of Acanthopagrus schlegelii in the Coastal Waters of the Eastern Taiwan Strait Using MAXENT with Fishery and Remote Sensing Data

Black sea bream, Acanthopagrus schlegelii, is among the most commercially valuable species in the coastal fishery industry and marine ecosystems. Catch data comprising capture locations for the gillnet fisheries, remotely sensed environmental data (i.e., sea surface temperature, chlorophyll-a concentration, and current velocity), and topography (bathymetry) from 2015 to 2018 were used to construct a spatial habitat distribution of black sea bream. This species is concentrated in coastal waters (<3 nm) from December to April (spawning season). The maximum entropy (MaxEnt) method and corresponding habitat suitability index among seasons were used to clarify the species’ spatial distribution and identify the seasonal variations in habitat selection. The patterns corresponded closely to the changes in oceanographic conditions, and the species exhibited synchronous trends with the marine environment’s seasonal dynamics. Chlorophyll-a concentration and bathymetry substantially influenced (80.1–92.9%) black sea bream’s habitat selection. By applying the MaxEnt model, the optimal habitats were identified with four variables including depth and satellite-derived temperature, current velocity and chlorophyll-a concentration, which provides a foundation for the scientific assessment and management of black sea bream in coastal waters of the Eastern Taiwan Strait.

Redescription and new record of the spongobiotic shrimp Periclimenaeus rastrifer Bruce, 1980 (Crustacea: Decapoda: Palaemonidae) from Taiwan

The palaemonid shrimp Periclimenaeus rastrifer is here reported from Taiwan based on three specimens. It bears a feeble but distinct anterodorsal lobe on the first pleonite (not reported before). The mouthparts, not previously described, are also remarkable by a multidentate apex of the mandibular incisor, asymmetric distal endite of the second maxilla, and expanded dorsal lobe on the second maxilliped merus. The species is thus redescribed here. One of the examined specimens possesses an unusual rostrum, and malformed telson and uropodal spinulation; the latter specimen is described and illustrated in detail, including the mouthparts. Previously, the only species in the genus published in faunistic repors from Taiwan were P. wolffi Bruce 1993 and P. gorgonidarum (Balss, 1913) recorded from the Taiwan Strait, and the Green Island, respectively; P. rastrifer is reported here as the first of the genus from Taiwan mainland

US policy on Taiwan 2002–2018

The Taiwan issue has always been the most sensitive and difficult in China – US relations. This article examines the US policy on Taiwan from 2002 to 2018 in the context of the Sino – US relations related to China’s territorial unification and sovereignty integrity. The article also concerns the global strategic interests of the United States. In particular, after the Trump administration came to power it fre- quently touched China’s bottom line of maintaining adherence to the One China poli- cy, which led to a rise of the Taiwan issue and aggravated the turmoil in the Taiwan Strait. The US policy toward Taiwan has changed not only on the issue of peace and stability across Taiwan Strait but also related to the increased risk of Sino – US mili- tary conflict. Therefore, it is very important to consider the US policy toward Taiwan during outlined period. The author adopts historical analysis and literature research methods, and based on a significant number of the scientific research results of Chinese and American scholars. The research content covers the Taiwan policy of the administra- tion Bush, Obama, and Trump. The author attempts to expose the strategic essence behind the US policy toward Taiwan, focusing on analyzing the relationship between US policymaking and the China and Taiwan’ relationship factors. The article finds that the US Taiwan policy can be generally regarded as subordination to the China strategy, but there are some cases different from it. On this basis, this article discov- ers variables of China – US relations, US – Taiwan relations, the United States Con- gress and Taiwan politics to prove the hypothesis that US Taiwan policy follows the China’s policy in the majority of cases.