(J. Yamashina Inst. Ornithol.), 25: 76-92, 1993 Breeding Biology of Dryocopus martius in Central Hokkaido Hirotomi Konishi*, Toshioki Suzuki*, Katsumi Tamada* and Yuzo Fujimaki* Abstract Observations were made of breeding Black Woodpeckers Dryocopus mar- in 1988. In 1987, eggs were laid between May 11-13, hatching on May 27 or 28. Three young fledged on June 29 1987, and on June 21 1988 respectively. Based on breeding records from the present study, and other sources in Hokkaido, young fledged in mid-june in southeastern areas, and in late June in other areas. The combined sex ratio for 26 broods was 1:1. Both the male and female incubated eggs and brooded nestlings during the day, up until the first week of the nestling period. Only the male incubated eggs and brooded nestlings at night during the corresponding period. Frequency of feeding increased from 10 times per day in the early nestling period, to 20 times per day in the middle of the nestling period. Feeding then began to decrease 4 to 5 days before fledging. Frequency of carrying faeces also began to decrese 4 to 5 days before fledging. Both males and females perched on trees near the nesting tree when flying to and from the nest. Frequency of perching after feeding began to increase before fledging. Freguency of drumming also increased just before fledging. Diet consisted mostly of ants, Formica sanguinea, Lasius niger, Camponotus obscuripes and C. herculeanus sachalinensis. Key words: breeding, Dryocopus martius, forest, Hokkaido. Received 8 November 1991, Revised 21 December 1992, Accepted 28 December 1992. * Laboratory of Wildlife Resource Ecology, Obihiro University of Agriculture and Veterinary Medicine, Inada, Obihiro, 080 Japan 76
periods in 1987. "("or")" indicate that exact time was unknown.
period in 1987. "("or")" indicate that exact time was unknown.
time of fledging.
period in 1988. "("and")" indicate that exact time was unknown.
Fig. 4. Seasonal changes in numbers of feeding (A) and carrying feces (B) per day, and ratio of B to A (C) in 1987. Broken lines=male, dotted lines=female, solid lines=total. Asterisks indicate fledging date.
Table 1. Seasonal fluctuation in the number of feeding and carring feces in 1988. Table 2. Number of feeding per hour in nestling period.
Table 3. Directions of flying to and flying from the nest in 1987.
Fig. 5. Seasonal changes in ratio of number of perching on trees other than the nesting tree to number of feeding (solid line) and perching time in minutes per day (broken line) before (A) and after feeding (B) in 1987. Triangle and asterisks indicate hatching and fledging date, respectively.
Fig. 6. Seasonal changes in number of drumming per day (A) and ratio of number of drumming to that of feeding (B) in 1987. Broken lines=male, dotted lines=female, solid line=total including cases in which sex was not determined. Triangle and asterisks indicate hatching and fledging date, respectively.
Table. 4. Fledging dates and numbers of nestlings of Dryocopus martius from various sources in Hokkaido and Tohoku district.
Kojima, K. & Ansawa, H. 1983. Habitat and food habit of the Black Woodpecker Dryocopus martius in Hokkaido. Tori 32: 109-111. Kojima, K. & Matsuoka, S. 1985. Studies on the food habits of four sympartic species of woodpeckers. II. Black Woodpecker Dryocopus martius from winter to early spring. Tori 34: 1-6. Matsuoka, S. 1979. Ecological significance of the early breeding in White-backed Woodpeckers Dendrocopos leucotus. Tori 28: 63-75. Matsuoka, S. & Kojima, K. 1979. Contents of fecal dropping collected in a nest of the Black Woodpecker Dryocopus martius. Tori 28: 97-98.