Nylon Mesh Trap & Metamorphosing Juvenile (Hasumi)

Nylon Mesh Trap & Metamorphosing Juvenile

To capture aquatic animals from a pond in Shaamar, Selenge Province, Mongolia, we settled 6 "collapsible nylon mesh traps (50 cm long, 5 cm-opening in each side for trapping, 2 mm-mesh)" at water depths of 20-30 cm in the opening near the edge of the shoe during 16-24 July 2005. At this time, we did not use any food for attracting these animals. We examined those traps every 24 hours after their settlement between 1030 h and 1130 h, and fixed trapped animals in 10% formalin.

(A) One of the 6 traps (photographed on 16 July 2005).

(B) One of metamorphosing juveniles of the tree frog Hyla japonica (photographed on 17 July 2005). This species seems to be unique only to Shaamar within Mongolia. I do not know why it exists sporadically in this area.

Every trap included a large number of aquatic animals such as back swimmers, caddisflies, diving beetles, dragonflies, leeches, shellfishes, spiders, and water scorpions. Metamorphosing juveniles of the toad Bufo raddei were also captured in the traps, but those of both the brown frog Rana amurensis and the salamander Salamandrella keyserlingii were not. No larva of any species was found in the pond.