1. Following the previous paper for 1956-57, comparative results of breeding at two nest-box colonies of Grey Starling were discussed based on the data of 1956-1963 inclusively (1958 and 1962 lacking). 2. Correlations of weather, especially temperature, with the frequency of start of egg laying were analysed from the average laying dates and the earliest laying dates. 3. Annual variation of the average laying dates paralleled at two colonies and this suggested the correlations with the temperature in the later part of April. 4. The significance of the earliest laying dates were discussed and analysed, and the temperatures during 10 days before the laying were considered as critical, since they were most constant in different years and localities. The warmth sum and sunshine hours were also given. 5. Food was regarded not as a timing factor but as a regulating nutritive factor of breeding and discussions were given from this point of view. 6. Annual earliest egg laying dates were significantly a few days earlier at urban than rural colony and this was supported by always slightly (0.2-2.7°C) higher 5 days means of average temperatures at the urban area. 7. The psychological factors which modify the timing of actual egg laying after egg laying temperature threshold is reached were discussed based on observations. 8. Clutch size was significantly larger at urban than rural colony and this may be correlated with entirely different food supply. The urban food was much more miscellaneous with animal and plant (fruits) species. 9. After the nest-boxes were attached there was noticed a common tendency at two colonies that the percentages of local maximum clutch sizes rose in the 2nd to 3rd years and decreased in the 4-5th years, thus suggesting the population turnover of age classes. 10. At both colonies larger clutches tended to be laid at the beginning and smaller ones towards the end of the season. The reason and possible evolutionary significance were discussed.
During 1960-63, 70 nests of the House Swallow Hirundo rustica were measured in Hachioji area, Tokyo. Five measurements taken were: length, width and depth of the inside, height of the outside and the distance of the space above the nest. The variations and correlations of these measurements were analysed as shown by figures 1-13. The results are summarized as follows: 1. The pair of swallows brought nest material (mud) average every 73 seconds and spent average 34 seconds at nest each time. They worked average 27 times per hour, but chiefly during the morning and completed the nest average by 10 days. 2. The length varied 4.8-12.1 (av. 7.9±σ1.05)cm, the width 7.5-14 (av. 9.9±1.23)cm, with difference of the length and width 0-6 (av. 1.7)cm. 3. The average of length+width varied 7-13 (av. 8.9±1.09)cm, the depth 1.5-5 (av. 3.2±0.27)cm and the height 2-32 (av. 7.8±6.04)cm. The space above the nest varied 4-42 (av. 10.±2.78)cm. 4. Variations of nest size by old and new nests, indoor and outdoor nests were analysed .
1. In 1957, His Highness the Crown Prince had two kinds of group nest-boxes set up in his garden for the Grey Starling, Sturnus cineraceus. The author had the honour of examining the result of nesting experiments with these interesting nest-boxes during the seasons of 1957-1963. 2. One was Danish type of four sided group nest-boxes with 5 nest-cells (one upper and four lower) on each side. Usually the upper cell was successfully used but lower nests were also occupied by putting a few nest material or by completing the nest. Some birds indulged in nesting in different nest-cells in turn exchanging the nest material, thus losing the time of egg laying. Others laid a single egg in incompleted nest or laid half clutches in two adjacent nest-cells. In this case, both were incubated (possibly by a parent) but did not hatch at normal date (the 12th day) and the eggs were found abandoned at 14th day. 3. These confusions in breeding were also noticed in the other type, the lateral group nest-boxes consisting of 30 nest-cells, with the entrance on alternate sides. This newly devised type was colour painted from the second year by units of 5 nest-cells, white-yellow-unpainted-green-unpainted-red from right to left (red and green were reversed in later years). 4. It was proved that the distal nest-cells particularly of the white (and yellow) end were better used than those of the middle part where no successful clutch was laid. This was probably because the birds tended to extend the nest territories from the free end toward the middle. 5. The white was best used (though with favourable position effect of being at the end), yellow, red and unpainted were almost the same, but green could be suspected to be disliked by the birds. Red when at the end was used successfully but was only nested when at the middle. However, no egg was laid in green even when at the end though was nested possibly merely as territory occupation. It was least used when at the middle.* 6. In conclusion, the group nest-boxes were readily used by the starlings and were proved to be useful for experiments with colour preference and other behaviours, but had some inefficient effects due to their nest-territoriality. A new type of lateral group nest-boxes was set up in 1964.
On 29 November, 1963, excellent photographs of a big roost flock of Grey Starling were taken by Mr. Shigemoto Otaka at Koshigaya roost, Saitama Prefecture. Number of birds were counted by checking each bird within 2-5cm squares on the tracing papar attached on the photographs enlarged to 40×23cm. Even minute dots of birds could be checked with light from below. In a photo of distant flock estimates of densities per square were made by counts with sample squares. The results of counts from four (three show part of the flock) photographs well coincided and 15, 000 birds were determined for this roost in the early winter. Former observational counts were 49.690 birds in February and only 1, 500 birds in April, 1960.
In August 1963, Umitaka Maru, a training ship of University of Fisheries, made a research cruise in central Japan Sea. Birds and insects observed during this navigation were recorded with meteorological notes. Twenty or thirty of Streaked Grasshopper Warblers Locustella lanceolata were encountered and one was obtained on August 21 in 36°54'N, 134°47'E and one Middendorff's Grasshopper Warbler L. ochotensis was captured on August 22 in 39°13'N, 135°02'E. On these days a low pressure storm of the maximum wind velocity 15m/s passed this sea area, causing strong NE winds at its front and accompanying heavy rains and SW winds south of it. On both days, dragonflies, Pantala flavescens, also passed near the ship. Apparently, the storm had drifted these birds and dragonflies (which were otherwise found near the coast) to the central Japan Sea while they were migrating along the coast.
The comparative study of the ontogeny of behaviour should be of evolutionary interest, as in the morphological characters. Here some reported data of observations of this sort are extracted for comparison from the works of Barrand (Great Tit, Chaffinch), Blase (Red-backed Shrike), Kuroda (Grey Starling), Messmer (European Blackbird. Original was not available) and Sauer (Garden Warbler). Twenty four behaviour items classified into sight development, physical behaviours (preening, etc.), self protection (crouching, fleeing, etc.), social behaviours (aggressiveness, juvenile song, juvenile nesting, etc.) and food getting (oriented gaping, pecking, species-specific use of bill, self foraging and drinking, etc.) were selected for comparison. It could tentatively be concluded that: 1. The duration from hatching to self foraging does not differ much by species with different habits and duration of nestling life. This should there-fore be the evolutionary basic Passerine character. 2. The hole and open nesters would have developed later adaptively. The nestling life was lengthened in the hole nesters (about 20 days) and shortened in the open nesters (10-15 days) as the result of natural selection against predators, but the basic growth pace was not changed. Thus hole nest chicks that stay longer in the nest are fed by parents shorter time after flying since they are well grown and open nest chicks fly precociously and are fed longer (Thus they retain incomplete adaptation against the danger of predation when flying). 3. This difference of the nestling period caused the difference in the timing of physiological and behavioural growth of early nestling life, such as eye-opening, lateral sight, preening and self protection, etc. These were accerelated in open nest chicks so as they have developed by the time of their precocious flying from the nest. 4. But, this accerelation of the occurrence of behaviours seems to have not influenced the basic timing of the final completion of self foraging. However, at the time when self foraging becomes established species-specific use of the bill (and feet) occurs similarly at around 20-25 days after hatching irrespective of the difference of habit by species. 5. The social habits occur first as an aggressiveness against each other (head forward posture, maintenance of individual distance) at different period by species (this occurs early at about 20 days in strongly territorial species), but always after or when the self foraging is established. 6. These species-specific behaviours (4 and 5) which occur latest during the ontogeny should be the ethological characters which have evolved recently.