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Many marine organisms broadcast gametes for external fertilization, thus conspecifics need to concentrate the time of gamete release through synchronization with environmental factors. We investigated the timing of spawning in two sea urchin species, Tripneustes gratilla and Toxopneustes pileolus, by assessing the spawning potential of individuals using both surveys and experiments in southern Taiwan from March to November 2010. We developed a new method to observe the spawning potential without sacrificing any individuals, defining those individuals‐initiated spawning within 30 min after 10 s of exposure to air as having the spawning potential. We discovered that the percentage of individuals with spawning potential, that is, the spawning ratios of the population, varied greatly from 0% to 80% in To. pileolus and from 0% to 50% in Tr. gratilla within the reproductive seasons. We evaluated the possibility of a lunar/semilunar rhythm of spawning ratios of the population and tested three environmental factors, that is, light intensity, tide, and temperature that could potentially affect the spawning potential of the sea urchins by experiments. Individuals with spawning potential were neither randomly nor evenly distributed among days but were aggregated on certain days; however, no lunar/semilunar rhythm of the spawning ratios was detected within the reproductive season. The possible role of the tidal factor within a day was not found in experiments in either species. However, when water temperature was >27°C in our surveys, significantly higher spawning ratios were observed in To. pileolus, but not in Tr. gratilla in the reproductive season. A further temperature experiment in To. pileolus supported the positive role of high temperature on the spawning ratios of individuals. In addition, To. pileolus was more likely to spawn during the day than at night, and the light/dark experiments suggested that the spawning potential was controlled by an endogenous biological clock rather than by the ambient light conditions directly. The lack of rhythmic pattern and yet concentrated spawning of these sea urchins may be adaptive to avoid predation. [ABSTRACT FROM AUTHOR]

Beaches provide a buffer zone between the sea and the land, which mitigates the impact of natural hazards on waterfront residents. In this study, the beach at the Dakenggu community in Suao Township, Yilan, was used as a long-term monitoring site for ghost crabs. The survey was conducted by researchers in collaboration with local residents, which can be considered community-based citizen science. In collaboration, researchers and residents conducted monthly surveys. The findings showed that Ocypode sinensis was a dominant species on the Dakenggu beach. Juvenile O. sinensis were more abundant in the spring (April) and the summer (July–September). Except in September, no sex predominance was observed in other months, which may be related to the breeding period of the crabs. As far as other data are concerned, O. sinensis females were significantly larger than males, and O. sinensis occurrences exhibited a significant positive correlation with temperature and a significant negative correlation with relative humidity when weather data for the survey days were analyzed. Multiple studies have shown that the ghost crab population is highly affected by offroad vehicle use on the beach. As a result, local residents can use the findings of this study to develop corresponding conservation strategies, such as permitting off-road vehicle use only in the winter (November–February) and planting coastal plants as natural barriers to prevent vehicles from destroying ghost crab habitat. Long-term environmental monitoring through community-based citizen science can document changes in the local environment, and such information can be the basis for increased community resilience to face the challenges posed by environmental change. [ABSTRACT FROM AUTHOR]

The article highlights the urgent need for conservation strategies for land hermit crabs due to unsustainable and illegal wildlife trade. Land hermit crabs are popular as pets worldwide, but captive breeding is challenging, so they are sourced from the wild. There have been numerous cases of unregulated and unsustainable trading, with thousands of individuals sold each week. Land hermit crabs play a vital ecological role and may be at risk of endangerment due to exploitation and habitat destruction. The article also discusses a recent incident of smuggling and emphasizes the need for updated regulations and enhanced enforcement to combat illegal wildlife trade. [Extracted from the article]

Citizen science is a key approach in scientific research that involves crowdsourced data collection for environmental monitoring and conservation. Participants in citizen science can gain scientific knowledge, change their pro-environmental attitude and behavior. Taiwan Roadkill Observation Network (TaiRON) was founded in 2011 and has a community of approximately 20,000 members. To collect data for further biological research, participants adopt a simple approach: taking pictures of roadkill and uploading them to a database. While many studies have explored citizen science learning outcomes, this study examines how a program with a unique participant task – photographing road kill – has an impact on participants pro-environmental learning. The learning outcome with the largest change was environmental attitude, suggesting that the participants' feelings, awareness, and values regarding the environment changed after joining TaiRON. The reasons for the attitude changes could be attributed to the characteristics of TaiRON's work: participants collect data from animal carcasses, prompting them to reflect deeply on the value of life. The second key learning outcome was behavioural intention, which means participants were driven to action to mitigate roadkill occurrence. Our results provide an example of evaluating learning outcomes in citizen science and also contribute to promoting environmental literacy. [ABSTRACT FROM AUTHOR]

Body size is a crucial metric that is often obtained during the breeding migration of female land crabs. Most commonly, these measurements are obtained by hand but hand-measuring them carries risks for both crabs and researchers. In this study, we developed a novel "photo-image approach" to measure the maximum carapace width of Cardisoma carnifex (Herbst, 1796) in the field, and compared the results with hand measurements. We found a significant relationship in the maximum carapace width measured between the two approaches (Linear regression, p < 0.0001 , r 2 = 0.99). The difference (0.54 ± 0.18 mm) and relative error (0.61 ± 0.19%) in the maximum carapace width measured between the two approaches were minimal. We suggest that the photo-image approach is feasible for determining crab size in the field. The approach holds promise for its application in citizen science projects, facilitating advancements in crab research. [ABSTRACT FROM AUTHOR]

Coastal forests can increase the resilience of seaside communities against natural disasters. These forests also provide other benefits, including food and an avenue for economic growth. The Dakenggu community in Suao, Yilan (Taiwan), is adjacent to a coastal forest with an area of nearly 114,000 m2. Artificial plantation has been performed locally in this area since 1977 to prevent the loss of beaches. The coastal forest area was estimated through drone aerial photography combined with a geographic information system. We found that Pandanus tectorius (11.5%), Casuarina equisetifolia (30.8%), Cerbera manghas (4.07%), Hibiscus tiliaceus (5.2%), and grass (23.52%) are the dominant species in the plant community of Dakenngu coastal forest, which together accounted for 75.1% of the total land area. The area covered by different species in the coastal forest was examined and estimated as well. The height and diameter at breast height (DBH) of the main tree species in five transects were surveyed, and we also found some significant differences among transects that correspond to cohorts planted at different times by the Forestry Bureau. We also performed a survey of land crabs in the same transects over five months to infer any differences in land crab species among the transects. We found that the transect dominated by H. tiliaceus had a larger population of land crabs than others. We revealed that the mudflat crab Chiromantes haematocheir prefers to live under H. tiliaceus. Finally, we propose recommendations for improving the biodiversity of the Dakenggu coastal forest so that it can become a sustainable resource for its residents. [ABSTRACT FROM AUTHOR]

Crab-eating mongooses (Herpestes urva) are widely distributed across Southeast Asia. In Taiwan, the mongoose (H. urva formosanus, endemic subspecies) is a protected species under the Wildlife Protection Act. Crab-eating mongooses have been observed near streams, riversides, agricultural lands, and shallow mountain areas. Additionally, as described in this short communication, by using a remote camera, we observed a small population of mongooses in the coastal forest in Kenting National Park in Taiwan. The mongooses in the coastal forest were observed eating land hermit crabs, which is the first-ever recorded observation of this behavior. Mongooses are known to consume crabs (Brachyura), insects, and some small reptiles. However, this article presents the first record case of mongooses using stone anvil to crack open land hermit crabs. From our observations and field records, we determined that mongooses use flat rocks as anvils and their front paws to tap hermit crabs' shells repeatedly to break the shells and remove the hermit crabs. We also observed that the mongooses only ate the abdomens of large hermit crabs. Additional studies are necessary to determine why the mongooses migrated to the coastal forest and how they learned to open hermit crab shells. This behavior of mongooses might help them move into living in coastal forests. [ABSTRACT FROM AUTHOR]

Seagrass meadows serve as critical marine habitats, offering numerous benefits to both humans and wildlife. Taiping Island, situated in the South China Sea, has been historically known for its abundant seagrass meadows. However, satellite imagery suggested there was a low density of seagrasses around Taiping Island. On the other hand, many green turtles (Chelonia mydas) were observed from the shore. To investigate this phenomenon, we conducted drone surveys of the shallow reefs and discovered a density of 902 ± 601 (mean ± SD) individual turtles per square kilometer during high tides. In addition, we conducted a cage experiment to test the hypothesis that large herbivores are impacting seagrass abundance negatively. The results indicated that the blade lengths of seagrasses in cages were significantly longer than those outside. It is likely that large herbivores such as green sea turtles are the key consumers of seagrass on the shallow reef flats of Taiping Island. Accordingly, further research and management should take into account that the increasing number of sea turtles may deplete the seagrasses and have an impact on the seagrass ecosystems. • A density of 902 ± 601 (mean ± SD) green turtles (Chelonia mydas) per square kilometer during high tides was observed around Taiping Island. • A cage experiment indicated that the blade lengths of seagrasses in cages were significantly longer than those outside. • It is likely that large herbivores, such as green sea turtles, are the key consumers of seagrass on the shallow reef flats of Taiping Island. • We provide management insights for green turtles and seagrass ecosystems. [ABSTRACT FROM AUTHOR]

This article provides updates on the incident involving the illegal catching of land hermit crabs in Okinawa, Japan. The author regrets to inform readers that the website link to the incident mentioned in a previous paper has expired, but provides a new link for reference. The penalty for the illegal catching has been determined, with the couple being required to pay JPY 200,000. However, this punishment did not have a deterrent effect, as more individuals from different countries have been arrested for similar offenses. The article emphasizes the need for nations and governments to address the unsustainable catch of these species and implement strong management policies to prevent further depletion of hermit crabs and potential ecological changes. [Extracted from the article]

An encrusting sponge, Terpios hoshinota, has the potential to infect all species of stony corals in shallow reefs and killing them. It caused a decline in coral coverage in two south-eastern islands of Taiwan. We proposed two hypotheses to examine how the sponges kill the corals, namely, light blocking and toxins, and tested by in-situ experiments. The results revealed that both light blocking, sponge toxins, and particularly the combination of both factors were effective at inducing tissue damage in stony corals over a short period. Second, to answer why the sponges killed the corals, we tested two hypotheses, namely, gaining nutrients versus gaining substrates for the sponge. By analyzing the stable isotopes 13C and 15N, as well as exploiting an enrichment experiment, it was possible to determine that only approximately 9.5% of the carbon and 16.9% of the nitrogen in the newly grown sponge tissues originated from the enriched corals underneath. The analysis also revealed that the control corals without isotope enrichment had higher δ13C and δ15N than the control sponges, which was an additional indication that T. hoshinota did not rely heavily on corals for nutrients. Therefore, our results support the hypothesis that the encrusting sponge did not kill corals for food or nutrients, but rather for the substrate. [ABSTRACT FROM AUTHOR]

Finding suitable habitats for specific functions such as breeding provides examples of key biotic adaptation. The adult marine midge Pontomyia oceana requires an extremely specific habitat, i.e., hard substrates above water in shallow water, to deposit fertilized eggs. We investigated how these sea surface-skimming insects accomplished this with a stringent time constraint of 1–2 h of the adult life span in the evenings. We observed that in artificial containers, midges aggregated at bright spots only if the light was not in the direction of the sea. This behavior could potentially attract midges toward the shore and away from the open water. Experiments were performed in the intertidal zone in southern Taiwan to test three hypotheses explaining such behavior: gradients of temperature and CO2, and soundscape. No differences were observed in moving directions or aggregation of midges under artificial temperature and CO2 gradients. However, midges preferred sounds at 75 Hz compared with other frequencies (all ≤300 Hz) as observed in a field experiment involving floating traps with loudspeakers. Moreover, when background noise was experimentally masked using white noise of all frequencies, midges were significantly more likely to aggregate at bright spots in the direction of the sea than in the absence of white noise. These results establish that sound is used by midges to navigate in dark seas and move toward the shore where exposed hard substrates are in abundance. Marine mammals present well-known cases of sound pollution at sea; here the finding in the insignificant marine midge is just the harbinger of the potential effects noise at shore may have to affect critical reproductive stages of marine organisms. [ABSTRACT FROM AUTHOR]

Terrestrial hermit crabs play a significant role in coastal ecology. For example, as seed dispersers and debris scavengers in coastal forests, they accelerate the decomposition of organic substances. In the Indo-Pacific Ocean, Coenobita rugosus, C. brevimanus, and C. cavipes are the three most common species of terrestrial hermit crab. Because the mechanisms that contribute to the sympatry of these three species of crab have not been identified, this study investigated the three most likely explanations: niche differences, competition, and predation. The results showed that the three species displayed niche differences in terms of seasonal activity, habitat, utilization of shells, and food preference, suggesting that competition for resources is avoided. The habitat of terrestrial hermit crabs in Taiwan is closely associated with that of humans. Our study helps improve our understanding of the ecology of terrestrial hermit crabs and their conservation. [ABSTRACT FROM AUTHOR]

Numerous environmental factors can influence body size. Comparing populations in different ecological contexts is one potential approach to elucidating the most critical of such factors. In the current study, we found that the body size of the land hermit crab Coenobita rugosus was significantly larger on Dongsha Island in the South China Sea than on other eco-islands around Southern Taiwan. We hypothesized that this could be due to differences in (1) shell resources, (2) parasite impact, (3) competition, (4) predation, and (5) food. We found no supporting evidence for the first three hypotheses; the shells used by the hermit crabs on Dongsha were in poorer condition than were those used elsewhere, extremely few individuals in the region had ectoparasites, and the density of hermit crabs varied considerably among localities within each island. However, significantly higher percentages of C. rugosus reached age 3 years on Dongsha than at Siziwan bay in Taiwan. Two growth rate indices inferred from size structures suggested faster growth on Dongsha than at Siziwan. The condition index (i.e., the body mass/shield length ratio of C. rugosus) was also greater on Dongsha than at Siziwan. Therefore, Dongsha hermit crabs seem to have superior diet and growth performance. Seagrass debris accumulation at the shore of Dongsha was considerable, whereas none was observed at Siziwan or on the other islands, where dicot leaves were the dominant food item for the vegetarian hermit crabs. We then experimentally evaluated the possible role of seagrass as food for C. rugosus. The crabs on Dongsha preferred seagrass to dicot leaves, and their growth increment was faster when they fed on seagrass than when they fed on dicot leaves; no such differences were found in the Siziwan hermit crabs. The aforementioned results are compatible with the food hypothesis explaining the size differences among the islands. The predator hypothesis could explain the greater life span but not the other findings. Populations of C. rugosus on islands with seagrass debris piles probably contribute more to the gene pool of the species because higher proportions of these populations could achieve high fecundity. The fate of these terrestrial hermit crabs may rely on the health of underwater seagrass ecosystems that are under threat from global change. [ABSTRACT FROM AUTHOR]

Simple Summary: Identification of existing and potential irrigation ponds is essential for creating waterbird refuges to secure habitats for wintering waterbirds in anthropogenically influenced areas. In total, 45 ponds were surveyed in the Taoyuan Tableland in northwestern Taiwan. The association between pond dimensions and bird-species richness and community composition was determined by comparing the responses of functional groups to pond configurations. The results demonstrated that waterbirds, compared with landbirds, have a stronger correlation with pond variables. Our study provided substantial evidence that these artificial ponds had also influenced the distribution of wintering waterbirds. Farm ponds or irrigation ponds, providing a vital habitat for diverse bird communities, are an environmental feature with characteristics that cross over typical urban and natural conditions. In this study, the species richness and community structure of irrigation ponds were characterized on the local and landscape scales. Within a landscape complex in the Taoyuan Tableland of Taiwan, 45 ponds were surveyed, ranging in areas from 0.2 to 20.47 ha. In total, 94 species and 15,053 individual birds were identified after surveying four times. The association between ponds and birds was determined to establish the effect of pond dimensions on species richness and community composition in the complex by comparing the responses of functional groups to pond configurations. Seven avian functional groups were identified. Compared with landbirds (i.e., families Alcedinidae, Apodidae, Icteridae, and Sturnidae), waterbirds (i.e., families Anatidae, Ardeidae, Charadriidae, Podicipedidae, and Scolopacidae) exhibited a stronger correlation with pond variables. Our study provides substantial evidence that these artificial ponds have influenced wintering waterbirds. The final results of this study may help stakeholders and land managers identify areas not to establish large-scale solar facilities considering waterbird habitats in pond areas. [ABSTRACT FROM AUTHOR]

To protect our environment, current firms are committed to the circular economy and process maintenance strategies to reduce the waste of resources. In this way, they can also save costs and create an enterprise image and value. Therefore, this study explores an imperfect production system with a circular economy and process maintenance activities, wherein the defective products can be converted into scrap returns (i.e., secondary raw materials) and products can be manufactured using mixed materials containing scrap returns. The proposed system considers multiple products with varying feed rates of scrap returns. According to the scenario of the aforementioned production system, this paper develops a production–inventory model aimed at cost minimization, in which the production run time, purchased quantity of material, number of maintenance times, and recovery rate are decision variables. Furthermore, we also develop a computational algorithm to obtain these optimal solutions efficiently. Finally, the numerical and sensitivity analyses based on a practical case are presented to illustrate the applicability of our method and some managerial implications. For example, both strategies efficiently reduce the total cost per unit time in the proposed numerical example. The sensitivity results can be used to determine the optimal combination of two strategies and the execution moment under various changes in cost parameters. [ABSTRACT FROM AUTHOR]

Abstract: Two new cyclometalated ruthenium sensitizers NC102 (1) and NC103 (2), where the two NCS- ligands of the N3 analog were replaced with the 2-thiophen-2-yl-pyridine and 2-benzo[b]thiophen-2-yl-pyridine ligands, respectively, were designed and synthesized for dye-sensitized solar cell applications. The effects of these two ligands on the photophysical behavior of ruthenium complexes were investigated by their optical, electrochemical, and photovoltaic properties. The sensitizer NC103 (2) with the fluoride substitution in the ligand exhibited the best cell performance with a short-circuit current (J sc) of 9.45 mA/cm2, an open-circuit voltage (V oc) of 630 mV, and a fill factor (FF) of 0.71, giving an overall power conversion efficiency of (η) 4.22% under simulated AM 1.5 irradiation. [Copyright &y& Elsevier]