1. This paper describes nesting- and foraging-sites of Reed Bunting
E. schoeniclus and Ussurian Yellow-breasted Bunting
E. aureola in the breeding season. Observations were made in the summer 1974 at Koshimizu in eastern Hokkaido. The area of study was about 11 ha.
2. The vegetation-type of the study area was as follows: A; pached willows (1.2m average hight), B': fallen reed near waters, B: reed (average hight 1.8m), C: mixture of reed and other forbs (hight 0.6-1.4m), D: mugworts (hight 0.8-1.5m), E: low grass (average hight 0.4m), F:
Alymus mollis grass (hight 0.5-0.8m), G:
Rosa rugosa bush (hight 0.5-1.2m), H:
Malus baccata bush (hight 1.8-3.0m), I: bareground and J: pasture.
3. The arrival of
E. schoeniclus at study area was two weeks earlier than thatof
E. aureola, but the breeding started at almost the same date.
4. The nesting-site of the two species were in or near B-type of vegetation (
E. schoeniclus) and in the C-type (
E. aureola), respectively.
5. The spatial distribution of foraging sites
E. schoeniclus tended to concentrate in B-type (dominant reed
Phragmites), while
E. aureola foraged extensively over the study area and relatively large portions of E-type of vegetation (low grasses).
6. Both species foraged on the ground where therewere a lot of deadplant cover (
E. schoeniclus 90.3%,
E. aureola 94.5%). However, there was a great the difference between the vegetation types that both unilized for foraging was great. The extent of utilization of type B by
E. schoeniclus was extremely great (59.50%), while the type E was used much less. In contrast,
E. aureola frequented the foraging grounds to utilize B and C types to a similar extent.
Foraging on plants were frequently seen (
E. schoeniclus 9.7%,
E. aureola 5.5%).
E. schoeniclus alone foraged on Aand B types. This species showed a behavior of moving up and down on the stem of B-type plants, while such a movement was never recognized in case of
E. aureola. The difference in the extent of utilization of B-type between
E. schoeniclus and
E. aureola might be attributed to thedifference of the foraging habit.
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