2002/6/8, Nanao
On June 8, 2022, a survey of organisms in rice fields was conducted at Asahi Elementary School in Nanao City. OUIK participated in this activity as a member of the Noto GIAHS Biodiversity Working Group.
The event began with an explanation of the day’s schedule by Mr. Sugimoto from the Nanao City Forestry and Fisheries Division, along with an introduction of the lecturer, Mr. Yoshihiro Ishiguro (Ishikawa Prefecture Federation of Land Improvement Association).
Mr. Ishiguro is well-versed in the environmental conditions of agricultural land and the organisms living there. He explained the correct usage of the nets used for capturing organisms, how to capture them, and how to observe them afterward. He advised the participants to “focus not just on catching many of the same species, but rather to capture a wider variety of organisms.”
After a short bus ride, we arrived at the rice fields in Ezo Town, Nanao City. The survey was to be conducted in the traditional earthen irrigation channels found in this area.
Recently, most irrigation channels have been made of concrete. Concrete channels are generally said to have lower leakage rates and can efficiently transport water. However, there are concerns that these channels do not allow for the accumulation of soil and sand, which serve as habitats for fish and shellfish. This makes it more difficult to maintain biodiversity as compared to earth-dug channels.
The students changed into boots, equipped themselves with nets and buckets, and ventured into the irrigation channel.
By placing the net on the bottom of the channel and stirring the surrounding water with their boots, various organisms began to fill the net. As they lifted the net and examined it closely, they discovered a variety of creatures hidden among the dead leaves and mud. They carefully transferred these organisms into the buckets and made sure to bring them back to school.
Upon returning to school, the students began to observe the captured organisms. With Mr. Ishiguro’s guidance, they sorted the organisms into different tanks according to species. In a short amount of time, they were able to catch a remarkable variety of organisms.
Mr. Ishiguro introduced the students to each of the organisms and their habitats. He explained about the differences in hand shapes between the common brown frog and the Japanese brown frog, the various types of dragonfly larvae, and how to distinguish male and female loaches. The students wrote down the names of the organisms they captured on their observation sheets while actively engaging in the discussions.
Finally, they experienced species identification using an app. They used the smartphone app called “Biome” to take pictures of the organisms and posted them. This app allows users to quickly identify the species and names of the organisms they discover, while the GPS function helps record their habitats. If everyone regularly uses this app for organism surveys, it will contribute to accumulating data on “what kinds of organisms inhabit where in the Noto region.”
As the lesson drew to a close, one student asked, “Can we keep a loach in our class?” Classmates had various opinions: “Can we create an environment where loaches can live comfortably?” “Is one loach okay? I think we can create a good environment,” “It might be too small and sad for it,” and “I don’t know what kind of food it eats.” Ultimately, they agreed, “Let’s return it to its original irrigation channel and observe the organisms in the school’s biotope.”
For the children in Noto, rice fields are still a familiar presence, but opportunities to interact with and learn about the organisms that inhabit them seem limited. This may have served as a chance for them to think about the future of rice fields and the creatures they nurture.
