Taiwan – 2018
Dates: July 21 – August 19, 2018
Partners: National Sun Yat-sen University (NSYSU), Dongsha Atoll Research Station (DARS), Tunghai University, Green Island Marine Research Station, Academia Sinica, National Museum of Marine Biology and Aquarium
Scripps Institution of Oceanography:
Lindsay Bonito, Staff Researcher
Chris Sullivan, Staff Researcher
Sho Kodera, Staff Researcher
Ben Frable, Marine Vertebrate Collections Manager
National Sun-Yat Sen University:
Dr. Keryea Soong, Professor
Shangyin “Vanson” Liu, Assistant Professor
Yi Wey, Researcher Assistant
Jen-Wei Kuo, Research Assistant
Dr. Colin Wen, Assistant Professor
Yu-De Pei, Research Assistant
Chieh Hsuan “Sandy” Lee, Graduate Student
Wei-Chen “Sharon”, Graduate Student
Green Island Marine Research Station:
Dr. Ming-Jay Ho, Assistant Research Specialist
National Museum of Marine Biology and Aquarium
During the summer of 2018, the 100 Island Challenge team collaborated with Taiwanese researchers from institutions including National Sun-Yat Sen University (NSYSU), National Museum of Marine Biology and Aquarium, Tunghai University and Green Island Marine Research Station to survey the reefs surrounded Taiwan and its offshore islands. In the first few days of the expedition, a large-area imaging workshop was coordinated with NSYSU to share large-area imaging techniques and methods with Taiwanese researchers in addition to sharing specific 100 Island Challenge protocol. This day-long workshop reviewed imagery collection, technical support, 3D model processing, and ecological data extraction.
Four islands were selected for survey within Taiwan during the 2018 expedition over the course of one month. Survey areas included Kenting National Park in south Taiwan, Dongsha Atoll, Orchid (Lanyu) Island, and Green (Ludao) Island.
The first two weeks of the expedition were dedicated to survey Dongsha Atoll, a remote atoll in the South China Sea. The atoll is circular with a diameter of 25km with a small island on the west side (~2km2) with a marine research station to support fieldwork. Partnering with NSYSU researchers, the team was able to survey 23 sites for photomosaics around the entire atoll. Of those 23 sites, 18 were surveyed to record the fish assemblage and collect benthic photoquadrat imagery. On the cardinal sides of the atoll, 4 temperature loggers were deployed to quantify the sea temperature around the atoll. The general impression of the reefs of Dongsha was a positive one, with most surveyed reefs being ‘healthy’ although in different coral dominated states. There seems to be an interesting trend moving around the atoll in terms of dominant coral type. The north side of the island was largely dominated by soft corals, the east side was mixed between hard and soft, and the south side largely hard corals species. The diversity of hard coral species on the south side was quite high, both morphologically and taxonomically. There was very little macroalgae to be found around the atoll, either calcified or fleshy. The fish community was dominated by damselfishes and wrasses, particularly at the soft coral dominated sites. The fishing pressure seemed to be relatively high, despite being in a national park, as many fishing vessels were observed within park boundaries and discarded line found throughout the forereef. Few large fishes were observed over the course of two weeks, and no sharks were seen on the forereef. The oceanography around Dongsha is particularly interesting, notably the internal wave activity that is present around the entire atoll. Similarly, the currents can be quite strong, seemingly influenced by tidal flow.
Simultaneously a second survey team collected data in Kenting National Park with National Sun-Yat Sen University (NSYSU) and National Museum of Marine Biology and Aquarium partners. Although the conditions were more challenging, namely poor visibility, the team managed to collect 3D mosaic imagery, fish data and benthic photoquad images from 12 sites within the park.
The offshore islands, Orchid and Green, were the last to be surveyed by the 100 Island Challenge team. The Scripps scientific team was joined by researchers and students from Tunghai University and Green Island Marine Research Station to conduct reef surveys. Orchid Island is culturally interesting as it is home to some of the last indigenous populations in Taiwan. The reefs surrounding Orchid were qualitatively in good condition, with decent coral cover and a seemingly stable fish community. A notable feature of the reef on Orchid was its complex reef structure, very different from what was observed in Kenting, Dongsha or Green Island. Although Orchid does sustain tourism, it is minimal compared to Green Island, despite Green Island’s smaller size. In contrast, Green Island reefs showed more signs of reef degradation, as the fleshy macroalgal cover was much higher in comparison to other Taiwanese sites. Reef structure was less complex than neighboring Orchid. The fish assemblage at Green Island was less diverse with generally lower fish abundance. Wrasses were the most common genera observed in Green, similar to Dongsha and Orchid.
The Taiwanese islands offer interesting perspectives and gradients in terms of human activity and use as well as oceanography. Human impacts vary dramatically across the Taiwan landscape, ranging from seemingly minimally impacted Dongsha Atoll where limited land-based impacts exist but pressure from illegal fishing activity is evident, to Green Island where reefs feel the impact of intensive tourism pressure and moderate fishing activity. More background research needs to be conducted to understand the complex oceanography of the region and how the effects of internal waves and currents impact the reef landscape.
The 100 Island Challenge team will return to Taiwan in 2020 to repeat sampling and recover temperature loggers, with the goal of understanding change in fish and benthic communities over time. The expedition team is deeply appreciative to colleagues and collaborators for their expertise and logistical and financial support in planning and executing a successful expedition.