2024年7月，北海道石狩川沿いにて，羽色に異常があるシマセンニュウ Helopsaltes ochotensis の雌1個体を捕獲した。本個体は全体的には通常の羽色を呈していたが，初列風切羽，次列風切羽，尾羽の一部が異常に白変していた．これらの白変している羽の配置より，本個体の羽色の異常はリューシズム（Leucism）に分類されると考えられる．本稿はセンニュウ科におけるリューシズム個体の初記録である．

The behaviour of a pair of Spectacled Guillemots Cepphus carbo in a nest was recorded by a small 4K camera during four breeding seasons. Parents started to visit the nest in mid-April to mid-May, and laid eggs in mid-May, 2 – 9 days after copulation in the nest. Long (> 3 days) absence from the nest before egg-laying, i.e. exodus, was not observed. Clutch size was two in 2019 and 2020 and one in 2021 and 2022. Chicks were hatched after an incubation period of 28 – 31 days; two chicks fledged in 2019 and one in 2020 and 2022 at 35 – 46 day- age, but not in 2021 because two other birds took over the nest in mid-Jun. Males visited the nest more often than females during the pre-laying period but the time in the nest, the time for incubation and the frequency of feeds were similar. Parents brought mainly sand lance Ammodytes spp. in 2019 (85% in number) and 2020 (95%), but its proportion decreased in 2021 (58%), and they brought demersal fish only in 2022. No apparent sex differences in the prey species provided were observed. High-quality images collected by a small camera set in the nest help studies of behaviour of the burrow/crevice nesting seabirds during the pre-laying period.

The Great Crested Grebe Podiceps cristatus is a winter visitor in many parts of Japan. This species is known to breed in Hokkaido and a few areas of northern and central Honshu, and has recently expanded its breeding range. However, there have been no reports on breeding in Nagano Prefecture. Here, I report the first breeding record of the Great Crested Grebe in the prefecture, observed at Lake Suwa, central Nagano, from June to August 2024. On 7 August 2024, six chicks were observed along with a breeding pair.

The external morphology and DNA of a Phylloscopus specimen found in Fukui Prefecture in January 2021 were examined, and it was identified as a Kamchatka Leaf Warbler Phylloscopus examinandus. This is the first record of this species (considered a transient visitor in Japan except for the Shiretoko Peninsula) in Japan in winter.

Line censuses have been undertaken at the Imperial Palace, Tokyo, to reveal the avifauna, since 1965. Here we report results of the line census from April 1976 to March 1996. The line census was conducted on a route of 4.1 km between 9:00 – 12:00, in the same way as the census conducted continuously before and after this study. We divided the study period into the early one from April 1976 to March 1986 and the late one from April 1986 to March 1996, and compared the two study periods. We observed 23,190 individuals of 76 species in the early study period (68 censuses) and 29,887 individuals of 72 species in the late study period (95 censuses; 89 species through the whole study period). Comparing 14 species with the higher relative frequency in 10-year-period before the early study period, and the 4-year-period after the late study period as well as the two study periods, Aix galericulata, Anas zonorhyncha, Streptopelia orientalis, Nycticorax nycticorax, and Spodiopsar cineraceus seemed to decrease, while Yungipicus kizuki, Sittiparus varius, Parus cinereus, Hypsipetes amaurotis, Zosterops japonicus, and Emberiza personata seemed to increase. Among these species, Aix galericulata, Anas zonorhyncha, Streptopelia orientalis, Nycticorax nycticorax, Yungipicus kizuki, Parus cinereus, Zosterops japonicus, Spodiopsar cineraceus, and Emberiza personata fluctuated significantly between the early and late study periods. Five and six species without the higher relative frequency also significantly decreased and increased, respectively. For Nycticorax nycticorax, Cyanopica cyanus, Zosterops japonicus, and Spodiopsar cineraceus, in which the numbers observed changed significantly between the two study periods, the changes seemed related to seasonal change. Conversely, the other species in which the observed number changed significantly, did not seem to change seasonally but to increase or decrease through a year. From December to March, ca. 25 species were observed. Twenty seven and twenty five species were observed in April in the early and late study periods, respectively; thereafter the number of species declined and reached a minimum of 17 and 15 species in August, the early and late study periods, respectively, and then switched to an increase during September and November. In November, the number of species reached 23 and 26, respectively. However, the number of species did not differ significantly in any month between the two periods.

森林に生息する肉食性鳥類が狩りを行う場所を明らかにするため，小型哺乳類が営巣する樹洞周辺にカメラトラップを設置し，鳥類による狩りの有無を調べた．2017年12月～ 2019年11月に長野県伊那市のニホンモモンガ Pteromys momonga が営巣する樹洞，2021年9月～ 2022年4月に北海道帯広市のタイリクモモンガ P. volans が営巣する樹洞にそれぞれカメラトラップを設置した．その結果，伊那市の樹洞でカラス類 Corvus sp. がニホンモモンガを狩る様子と，帯広市の樹洞でフクロウ Strix uralenesis がタイリクモモンガを狩る様子が1例ずつ観察された．