CONTENTS


Q1 How was it formed?
Q2 Where does its name come from?
Q3 How big is the marsh?
Q4 Where does the water come from?
Q5 What lives and grows in the water?
Q6 What lives and grows around the marsh?
Q7 Who owns the marsh?
Additional Information


←HOME NEXT→


Q1  How was it formed?
  •  Its official origin is uncertain, but it is thought that it was left as a residual pond after flooding of  by the early Ishikari River.
  •                                    
  • ↑TOP
Q2  Where does its name come from?
  •  It relates to the name of the farm that was run by Sajiro Miyajima, founded in 1893 (Meiji 26), on the west edge of the marsh. Local people also called the marsh simply, “Ohnuma” (lit. big marsh), because the marsh was the largest of a number in the area.
  •  
  • ↑TOP
  •                                                 
  •                                                     
Q3  How big is the marsh?
  • Officially: Circumference: 2.7 km, Surface Area: 0.36 km2, Volume: 600,000m3 , Maximum Depth: 2.4 m, Average Depth: 1.7 m
  •  The surface are of the marsh used to be 120,000 tsubo (≒40 ha), but is now only about 30 ha. Furthermore, according to actual measurements, the maximum depth of the marsh was just 123 cm, and the average depth 86 cm.
  •              
  • ↑TOP
Q4  Where does the water come from?
  •  Spring water used to come from the bottom of the lake, but now melting snow and rainwater form the marsh.
  •  The water usage association, formed by local farmers, uses water drawn from the Ishikari and warmed in the marsh via a water channel in the east edge for irrigation, but only when they are planting rice.
  •      
  • ↑TOP
Q5  What lives and grows in the water?
  • Plant : Himebishi, Pond weed, Yellow Pond Lily, etc.
  • Fish: Carp, Cyprins, Japanese Dace, Lakeminnow, Asian Pond
  • Loach, Ten-spined Stickleback, Pond Smelt, etc.
  • Crustaceans: Swan Mussel, GoldenAppleSnail, Monoaragai
  •              
  • ↑TOP

Q6  What lives and grows around the marsh?

  • Grasses & Herbs: Wild-Rice, Reed Grass, Reedmace Sagebrush sp., Giant Knotweed, Gloden Rod, etc.
    Trees: Alder, JapaneseWillow, Kamtschatica,PanicleHydranger, Japanese Angelica Tree, ManchnrianAsh
    Birds: Great Reed Warbler, Black-Browed Reed-Warbler, Stonechat, Grey-Capped Greenfinch, Siberian Rubythroat, Reed Bunting, etc.(detail of waterfowl is as follows)
    Animals: Ezo Red Fox, Mink, Rat, etc.
  •           
  • ↑TOP
Q7  Who owns the marsh?
  •  It belongs to the state, the Ministry of Construction, and it’s treated as a normal river.
  •     
  • ↑TOP
Additional Information
  •  In the autumn and the spring, Miyajima-numa becomes a stop-off point for waterfowl, mainly anatidae, during their migration to wintering or breeding grounds.
  •  Among those birds are the white-fronted geese which use the marsh as a place to roost for about a month every spring and autumn, and eat fallen rice left in the surrounding rice paddies.
  •  Miyajima-numa has been used by generations of geese as the largest first gathering point in the autumn and the last in the spring in Japan, and their numbers now exceed 40,000.
  •       
  • ↑TOP