Biofouling is a significant problem in the aquaculture and marine shipping industries; thus, various antifouling methods have been developed to prevent the resultant economic losses. In the present study, the superhydrophobic surface of a lotus leaf was bio-mimicked to achieve antifouling. Specifically, fabric substrates with and without superhydrophobic coatings on the surface were installed on the Tongyeong yacht in December 2020 (group A) and April 2021 (group B), and the coverage of the attached invertebrates was recorded every month until August 2021. The coverage of solitary ascidians (Ascidiella aspersa and Ciona robusta) and branching bryozoans (Bugula neritina) was lower on the coated substrates than on the non-coated ones, and coating or non-coating was significantly correlated with the extent of coverage. Superhydrophobic substrates with a low surface energy and micro–nano dual structure may be unsuitable for the attachment of larvae. Therefore, superhydrophobic coating is a more effective and simpler method of antifouling for certain taxa than other antifouling strategies. However, the antifouling effect of the superhydrophobic substrate in group A reduced after 5 months from the first installation; thus, the durability of the antifouling coating should be further improved, and solving this problem remains a major task, necessitating further research.

A community of benthic invertebrates, including sessile adult-stage invertebrates, can negatively effect corrosion, deformation, and increased fuel consumption by attaching to artificial structures, a phenomenon known as marine biofouling. Investigating the relationship between benthic communities and artificial structures or substrates (to which the organisms attach) can help clarify the factors influencing marine biofouling. Therefore, in our study, natural (stone) and artificial (rubber, tarpaulin, and iron) substrates were installed in three harbors (Mokpo, Tongyeong, and Busan), and the structures of the communities attached to each substrate were compared. The total study period was 15 months (September 2016 to December 2017), and field surveys were performed at 3-month intervals. The three survey sites had significant differences in the structure of the sessile community present. In particular, Tongyeong was significantly different from Mokpo and Busan due to the continuous dominance of Cirripedia. When comparing natural and artificial substrate by sites, significant differences were observed in the community structure in all three surveyed sites. In Mokpo and Busan, colonial ascidians were dominant on natural substrate rather than artificial substrates; post-summer, Cirripedia coverage was higher on artificial substrates than natural substrate due to corrosion. Tongyeong showed a different pattern from that of Mokpo and Busan. After the summer, Bivalvia dominated on natural substrate over artificial substrates, affecting the differences between natural and artificial substrates. Our results demonstrate the recruitment patterns of sessile marine invertebrates according to substrate characteristics and can be used as basic information for biofouling management in marine environment.

Assessing and understanding the ecological impacts of marine invasive species is important for managing marine ecosystems, especially since their rapid growth, short reproductive cycles, and wide range of water temperature adaptability pose major challenges. In this study, conducted in Mokpo, South Korea, we explored the cohort dynamics and environmental influences on the ascidian Ciona robusta, which is considered a widespread invasive species. Through biweekly field surveys and quantitative measurements (dry weight, wet weight and body length) conducted from June to October 2022, we identified five distinct cohorts, challenging existing assumptions about lifespan and cohort patterns. All separation index value (which quantify differences between cohorts) exceeded 2, indicating clear separation of cohorts during the study period. The cohorts had a lifespan of between 4 and 10 weeks, much shorter than the previously reported maximum of 2 years. These differences suggest that local climatic conditions can have a significant impact on lifespan parameters. In addition, growth rates were significantly positively correlated with environmental conditions, particularly temperature. This highlights that while C. robusta growth rates are particularly sensitive to temperature changes, they showed relative tolerance to the salinity variations observed in this study. Therefore, this study contributes to the understanding of the population ecology of C. robusta in temperate marine ecosystems. In particular, it provides valuable insights for developing management strategies to mitigate the impacts of C. robusta due to climate change.

The complete sequence of the mitochondrial genome of Balanus trigonus Darwin, 1854 was examined using next-generation sequencing analysis. The complete mitogenome of B. trigonus has 15,336 bp in length and comprises 37 genes, namely, 13 protein-coding genes (PCGs), 22 tRNAs, and two rRNAs. Both the gene order and characteristics are consistent with those of other species within the family Balanidae. Phylogenetic analysis based on complete mitogenomes revealed taxonomic relationships among members of the family Balanidae.

The complete mitochondrial genome sequence of Dendrodoris krusensternii (J. E. Gray, 1850) was determined using next-generation sequencing. The complete mitochondrial genome of D. krusensternii is 14,361 bp long, comprising 13 genes, including 13 protein-coding genes (PCGs), 22 transfer RNAs, and two ribosomal RNAs. The nucleotide composition was estimated: 28.7% A, 14.8% C, 19.6% G, and 36.9% T. Phylogenetic analysis was performed using the maximum likelihood method (including 13 PCGs). D. krusensternii is related to the Phyllidiidae (superfamily Phyllidioidea), suggesting a distinct phylogenetic placement within Nudibranchia. This study represents a genomic resource, contributing to molecular studies on the evolution of the Dendrodorididae.