a. Earthworm Surveys
ESRI has discovered 34 new species and 8 new records of earthworms and has established a checklist of local earthworms containing 77 species.
b. Bio-inventories of Freshwater Crabs and Shrimps in Eastern and
ESRI has recorded 27 species of freshwater shrimps belonging to seven genera and three families and 15 species of freshwater crabs belonging to four genera and three families. In addition, researchers are continuing to conduct bio-inventories of freshwater crabs and shrimps in northern and central
, where they have already recorded 11 species of freshwater shrimps belonging to three genera and two families and seven species of freshwater crabs belonging to five genera and four families.
c. Establishment of a River Ecology Database
The Institute has completed additional surveys of the fish, shrimp, crab and bird resources at 121 major rivers to make the relevant ecological databases more complete, establishing a total of 508,124 items of detailed information, including 115,527 items for 145 fish species, 66,075 items for 33 shrimp species, 8,199 items for 37 crab species, 46,938 items for 223 bird species, 6,732 items for 25 amphibian species, 2,958 items for 33 reptile species, and 261,695 items for aquatic insects, freshwater snails, algae, dragonflies, land snails, butterflies, plants, water quality, and hydrology.
d. Surveys of Introduced Fish and Shrimp Species
ESRI’s researchers have discovered that, of the 51 rivers surveyed, non-native freshwater fish and shrimp species were found in 49 rivers. A total of 15 species of exotic freshwater fishes and two species of exotic freshwater shrimps were recorded. In addition, researchers completed a study of the impact on local rivers of the introduced species, the Red Swamp Crayfish
[ Procambarus clarkii (Girad)], and put forward an environmental impact assessment and possible prevention strategy for the species.
e. Land-cover Change Monitoring
Using remote sensing and geographic information system (GIS) technologies, the Institute has monitored land-cover change at the mouth of the
River and the Jiji Earthquake landslide region at Jiioujiioufong , enabling land-cover change to be quickly analyzed.
f. Fishway Migration and Swimming Ability Experiments on Fish Species
ESRI has completed submerged-orifice fishway migration experiments on eight species of native fishes. This was intended to determine the optimum and maximum water head difference in submerged-orifice fishways at different seasons for native fish species and to determine their migration behavior. Furthermore, ESRI has entered a cooperative research project with private business to study and develop ‘combined fishway’ . This type of fishway improves upon flaws in traditional fishways because the spoiler can be adjusted according to river flow to facilitate migration by fish and sand discharge requirements. In fish species swimming ability experiments, researchers have already tested the burst speed and cruising speed swimming ability of minnows [
Acrossocheilus paradoxus (Günther)], the Taiwan shoveljaw fish (
Scaphesthes barbatulus), cyprinids [Candidia barbata (Regan)], the Thick-head chub [Zacco pachycephalus (Günther)], the Pale chub (Zacco platypus), and the Common freshwater goby [Rhinogobius candidianus (Regan)]. The results of these experiments can be used by the relevant authorities in the planning and design of fishways.