Although zoos provide education on the conservation of wildlife on a global scale, there are few zoos that promote wetland education targeting local animals and environments. While the importance of conservation education activities and their implementation in all wetlands other than those registered in the Ramsar Convention is frequently mentioned, the current situation is that the content and perspective inherent in the method of implementation of wetland education programs that form a part of zoo education are not clear.The task of this study is to clarify the perspectives when conducting wetland education in zoos and aquariums (hereafter, “zoos”) in Japan. A practical program was conducted over a period of two years and seven months at the Tokyo Metropolitan Government Onshi Ueno Zoological Gardens. Episodes that occurred during the program were recorded in writing, and a questionnaire survey of visitors and students was conducted. As a result of the analysis and evaluation of the episodes and questionnaire survey, the following six points were identified as important perspectives for wetland education in zoos: (1) educational programs for natural environment conservation and wildlife protection, (2) targeting local animals and environment, (3) main Classification of Environmental Protection Activities (CEPA), (4) interpretation, (5) participation, and (6) education and exchange.

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In southwest Japan, there are many small wetlands formed and maintained by anthropogenic disturbance, including Sphagnum wetlands. The main species is Sphagnum palustre, which is listed in the red lists of all the prefectures in the Chugoku Region, Japan. However, studies have not clarified the relationship between anthropogenic disturbances and environmental conditions of Sphagnum wetlands. This study surveyed a Sphagnum wetland developed on a farmland in Tsuguro Highland in Okayama Prefecture. Local elderly residents were interviewed, and aerial photographs were interpreted to gather information on the history of the agricultural reclamation. Multilayer vegetation maps were drawn using unmanned aerial vehicles (UAVs) light detection and ranging (LiDAR) data. The groundwater level, water quality, and relative solar radiation were measured. Also, the terrain was analyzed as an abiotic factor. The farmland was reclaimed and abandoned in the 1970s and 1980s. A decision tree analysis determined the threshold value of abiotic environmental factors of Sphagnum palustre, and lower limits were set for the groundwater level and the relative solar radiation. Additionally, the potential habitat of Sphagnum palustre was estimated based on the threshold value, which displayed a high level of corresponding ratio in relation to the actual habitat. The habitat of Sphagnum palustre consisted of the agricultural reclamation up to the boundary of the valley bottom with the high water level and the half shade conditions provided by shrubs, such as Rosa paniculigera. It grows under shrubs, owing to the relatively low light conditions provided by the shade of the shrubs. In the study site, it was estimated that a suitable condition for Sphagnum palustre was provided by a high groundwater level caused by spring water flowing into the agricultural reclamation area, which has low water permeability and is invaded by shrubs.

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Seasonal changes in water chemistry and the influence of human impact on three adjacent springs and rainwater were investigated from 2015 to 2017. Subsequently, the results of this survey were used as teaching materials for science practical classes for elementary school students aged from10 to 11 years old. The water chemistry of the rainwater, the origin of the spring water, had a pH ranging from 4.4 to 5.3, electric conductivity 2 mS m^-1, and dissolved inorganic nitrogen (DIN) 470 μgN L^-1. The spring water in Kinmeisui, a place unaffected by human impact, had a pH ranging from 5.1 to 5.5, electric conductivity 2 mS m^-1, DIN 13 μgN L^-1. In the spring water of Motoyama, a place affected by human impact, the pH ranged from 5.8 to 6.5, electric conductivity 10 mS m^-1, and DIN 2000 μgN L^-1. Environmental parameters of Sugiyama elementary school located in the urban area had a pH ranging from 6.3 to 9.5, electric conductivity 24 mS m^-1, and DIN 5000 μgN L^-1. In the one spring closer to the city center, the water chemistry changed from weakly acidic to neutral and weakly alkaline with high values of electric conductivity and DIN concentration. This clarified that human impact on urban areas significantly affected the quality of the spring water. The science practical education was conducted for fifth-grade students in a Japanese elementary school while learning topics on the rivers and streams. The practice was themed 'A headwater of the urban river from Sugiyama elementary school'. The practice was aimed at answering these questions: First, do rivers start from the spring water on the slope? and second, how does human impact affect the water chemistry of the spring? We introduced topographical analysis using the 3D function of GSI Maps and colourimetric analysis of NO₂^--N concentration by a standard method. The fascinating contents for the students during the practical were the analysis of NO₂^--N concentration, and the spring as the headwater of the urban river, respectively. The students were evaluated based on the aims of this practice, and results showed that springs can be used as a science teaching material. Furthermore, we proposed four future studies to improve the quality of the science teaching materials, namely: the origin of the high concentrations of DIN in spring water located in urban areas, measurement of educational efficiencies, introduction into the subject education, and teaching materials for disaster education.

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Owing to high nutrient load in the Bibi River, Phalaris arundinacea shoots overgrew and clogged the stream by forming floating masses, resulting in the decline of submerged macrophytes. To restore submerged macrophytes such as Ranunculus nipponicus and Sparganium emersum, we partially removed the floating masses of P. arundinacea by adjusting the stream width to where the submerged macrophytes remained. Immediately after the partial removal of P. arundinacea, velocity of the stream increased whereas mud depth decreased and the bottom sediment became coarser in the riverbed. However, water depth decreased 4 years after the partial removal of P. arundinacea. Furthermore, coverage of R. nipponicus increased every year after the partial removal of P. arundinacea, whereas coverage of S. emersum increased the year after the partial removal of P. arundinacea but remained nearly stable for the next 6 years. By contrast, after the partial removal ofP. arundinacea, the coverage of emerged macrophytes P. arundinacea and Cicuta virosa continued to decrease, and they disappeared by the fifth year. Canonical correspondence analysis revealed that the coverage of R. nipponicus positively correlated with the increase in surface velocity and coarsening of the bottom sediment, but negatively correlated with mud depth. The coverage of P. arundinacea and Cicuta virosa negatively correlated with surface velocity and coarsening of the bottom sediment, whereas the cover of S. emersum positively correlated with water depth. Accordingly, changes in aquatic macrophytes would be the result of changes in physical environments following partial removal. The partial removal of P. arundinacea is considered to be an effective countermeasure because it suppressed the growth of P. arundinacea in the stream for at least 7 years.

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The bullfrog was introduced to Japan in 1918 to be farmed for human consumption. Japan began to export bullfrogs, which were important fishery resources for the nation, in 1932. However, the export was halted after bullfrogs sold to the United States in 1969 were found to have been contaminated by pesticides. Now, bullfrogs are being exterminated as invaders that threaten indigenous species. We conducted interviews regarding the bullfrog hunting carried out in Toyanogata Lagoon and tried to replicate the operations.

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In general, wintering dabbling ducks rest in the safety lakes and ponds during daytime hours and feed at shallow areas, such as flooded rice fields, during nighttime hours. Since it is difficult to observe Mallards Anas platyrhynchos during nighttime, I set a time-lapse camera with an infrared flash at the rice fields to study the time budget activities of Mallards. A time-lapse camera was set from December 15, 2019, to January 20, 2020, at the rice field near Katano-kamoike pond where is the Ramser site in Kaga City, Ishikawa Prefecture, central Japan. Photos were taken every 5 min from 17:00 to 07:00. The dabbling duck species photographed during the study period included Mallards, Spot-billed ducks A. zonorhyncha, Baikal teal A. formosa, and with the later two species were uncommon. The activities of Mallards were classified into eight categories: foraging, sleeping, preening, alert, agonistic activity, flying, courtship, and others. I counted the number of photographed Mallards in each category in each photo. During the study period, foraging occupied 20%–70% of the time budget and was the most frequent activity through the night. Mallards also allocated time to resting and preening, which are required to maintain their body condition. However, courtship was not recorded. These results reveal the importance of flooded rice fields as wintering habitats for Mallards and show how conservation strategies adopted around Katano-kamoike pond are effective for the conservation of dabbling ducks.

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[in Japanese]

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