OBSERVATIONS ON THE BEHAVIOUR OF THE HAMERKOP SCOPUS UMBRETTA IN UGANDA

Hamerkops were studied in Uganda, mainly in the vicinity of Kampala, during January-August 1964. Behavioural observations were made of nest-building pairs, as well as of non-breeding birds.
Locomotion and feeding behaviour are described. Diving take-offs and landings, essential for entering or leaving a completed nest, are sometimes seen in other situations as well. Birds sometimes forage while on the wing, in addition to the more usual method while wading.
The most frequently seen comfort movements and maintenance activities are described. Hamerkops do not excrete onto their legs when over-heated as do the storks. The resting posture of sitting completely down on horizontal branches, which is common among Hamerkops, apparently is not known in any of the herons or storks.
Primarily hostile (Upright and Forward Threat) and primarily sexual ("Yip-purr", Nodding and False Mounting) social displays are described. During False Mounting, birds mount their partners repeatedly without making any attempt at copulation; reverse mountings, in which the other partner assumes the top position, are frequent.
The large, hollow nest and its construction are briefly described. During the 6–7 week building period at one nest, at least 8000 loads of material were added to the structure. Both members have an equal role in nest-building, and generally work independently of each other. They showed no stick-exchange displays as do herons and storks.
When all known aspects of the Hamerkop's behaviour are considered, there appears to be little similarity with either the herons or the storks. In fact, present behavioural evidence does not seem to indicate a particularly close relationship with any other birds so far studied.     

THE FOOD AND FEEDING HABITS OF GOLDENEYE BUCEPHALA CLANGULA IN GREAT BRITAIN

The food and feeding habits of Goldeneye Bucephala clangula are described, based on the analyses of 51 stomach contents and a brief review of the literature. The type of food taken depends on the type of habitat being used, the availability and size of the food items and on the methods of feeding—though animal material largely predominates.
In estuarine and coastal areas, small crustaceans and in particular Carcinus maenas figured highly in the diet, with some molluscs and small fish. In two brackish-water feeding birds, seeds formed the bulk of the food, some caddis-fly larvae also being taken. In freshwater feeding birds insects predominated, particularly Trichoptera larvae, chironomid larvae and the adults of Corixa spp. Some crustaceans ( Asellus, Gammarus ) and small molluscs were taken and occasionally small fish. A small amount of plant material was taken in the form of seeds, mainly Potamogeton spp.
The relation between Goldeneye and fishing interests is briefly discussed and it is concluded that fish normally form a small part of the diet and it is unlikely that any serious depredation of fish stocks is common.     

A QUANTITATIVE STUDY OF THE DAILY ACTIVITY OF THE WARTHOG IN THE QUEEN ELIZABETH NATIONAL PARK, UGANDA

Warthog activity was recorded at 4-min intervals for continuous periods of 14 h on three consecutive days. The major activities were feeding or lying down and walking. The amount of time spent in feeding is related to the size of the animal and maximum-intensity feeding occurs in the early morning and in the late afternoon and evening. The animals drank usually only once each day. Adult females urinate much more often than males and this is thought to be a behavioural adaptation whereby the males can tell whether or not a female is in heat.     

STUDIES ON THE FOOD HABITS OF LESSER KUDU IN TSAVO NATIONAL PARK, KENYA

As part of a broader ecological investigation, in the framework of the Tsavo Research Project, food habits of lesser kudu have been studied during 2 y in Tsavo National Park (East). Free-ranging lesser kudu were observed, from a Land Rover, while feeding in different habitats and at different times of the year. Each time one animal fed on one individual plant was noted as one “food record”; some 2000 records are analysed in this paper. Leaves of trees and shrubs constitute the main bulk of the diet of lesser kudu. Creepers and vines, herbs, grasses, fruits and tubers of some root succulents contribute variable but relatively small proportions of the food. Pronounced local and seasonal variations in the composition of the diet were found. Local variations are mainly a result of differences in the vegetation of the different habitats. Seasonal variations are caused by changes in the vegetation's condition, depending on rainfall. Deciduous trees and bushes, herbs, climbers and grasses account for much smaller proportions of the diet during the dry season, when evergreen species are crucial for survival. Lesser kudu feed on a wide variety of plants, utilizing all layers of the vegetation that they can reach, at least to some extent. A total of 105 plant species have so far been recorded as being eaten by lesser kudu. With regard to food only, the vegetation changes in Tsavo National Park do not appear to have had any adverse effects on the population of lesser kudu. However, the amount of suitably structured habitat has been substantially reduced in recent years. If present trends continue, it may decrease further, to the point of jeopardizing the future of lesser kudu in large parts of Tsavo National Park.     

FISHING TECHNIQUES AND FOODS OF THE PIED KINGFISHER ON LAKE VICTORIA IN UGANDA

Douthwaite, R. 3. 1976. Fishing techniques and foods of the Pied Kingfisher on Lake Victoria in Uganda. Ostrich 47: 153–160.

Pied Kingfishers fish by diving from hovering flight or from perches; the choice is influenced by location of the prey and the weather, especially wind speed. 40–50% of the dives into Lake Victoria were successful compared with 11% on the Kazinga Channel, near Lake Edward, but dives were made more frequently in the latter area.

Analysis of pellets from the northern shore of Lake Victoria showed the bulk of the adults' diet was composed of Haplochromis, 55–108 mm (median 80 mm) total length, but that Engraulicypris urgenteus. 40–64 mm (median 52 mm) total length was more important numerically. Flying termites, Macrotermes sp., were occasionally eaten in large numbers.

Size selection related to development determines the proportions of Huplochromis and Engraulicypris in the chick's diet. by comparison with the adult most bone consumed by the chick is digested. Two caged juveniles ate about 34.5 g of fresh fish daily, 45% of their post-absorptive weights. Wild birds may consume even more.     

CINEMATIC OBSERVATIONS ON THE GROWTH AND DIVISION OF CHLOROPLASTS IN NITELLA

As it elongates from about 0.2 to 80 mm, the Nitella internodal cell shows an increase in plastid number from a few thousand to about 4 million. The increase takes place by plastid division. A continuous motion picture record followed a population of 8 plastids in an elongating cell until their progeny numbered 18, a span longer than 1 fission cycle for some of the plastids. One complete fission-fission cycle was about 22 hr. The highly directed nature of chloroplast expansion (elongation) is lost when cell wall strain (expansion) is mechanically inhibited by pressing the cell between glass plates. The plastids then expand about equally in all directions in the plane of the cell surface. When a new direction of maximum strain is introduced by the mechanical induction of a lateral in the cell, the plastids elongate in this new direction. The direction of the protoplasmic stream does not show this striking response to strain but tends to follow the lines of the chloroplast chains, not the long axis of individual plastids.     

OBSERVATIONS ON THE EFFECT OF ADDED HYPOCHLORITE ON THE NUMBERS AND KINDS OF BACTERIA IN MILK

SUMMARY: In an investigation of the effect of added hypochlorite on the bacterial flora and bacterial numbers of milk no bactericidal action was apparent within 15 min of adding the disinfectant unless at least 500 p/m available chlorine had been added. After 24 hr storage at atmospheric temperature a reduction in numbers was found with 10 p/m available chlorine and this became more pronounced with increased concentrations. Micrococci seemed more susceptible to the bactericidal effect than streptococci, which formed, after 24 hr storage, the predominant residual flora where 250 and 500 p/m available chlorine had been added. Acid production by lactic streptococci was retarded at concentrations greater than 50 p/m available chlorine in a 5 hr incubation period at 30°, but after a 24 hr incubation the decrease in acid production was only apparent when 500 or 1,000 p/m available chlorine was present. Little effect on acid production by lactic streptococci was found when less than 50 p/m available chlorine had been added. The residual chlorine content of rinses of equipment sterilized in hypochlorite solutions was negligible.     

NOTES ON THE HABITS AND STRUCTURE OF THE GUACHARO STEATORNIS CARIPENSIS

1. Steatornis is peculiar, perhaps unique, among birds in possessing two specialized means, one auditory and the other tactile, of locating objects in total darkness.
2. Owing to the peculiar position of the hallux and the fact that the much-abbreviated metatarsus is more or less on the same plane as the toes, the hind limbs are ill-adapted for walking or for perching on a branch, but they afford the bird a secure foothold when resting longitudinally on a ledge.
3. In the embryo the abnormally short metatarsus is incorporated in the body of the foot. Although anatomically distinct in the adult, functionally it remains a part of the foot serving to support much of the bird's weight when resting in its normal crouching posture.     

OBSERVATIONS ON THE BIOSYNTHESIS OF RAT BRAIN CERAMIDE AND CEREBROSIDE IN VIVO

Abstract— The incorporation in vivo of l -[¹⁴C]serine into ceramide and cerebroside of young rat brain has been studied. Acid hydrolysis of labelled ceramide and galactosyl-ceramide followed by selective partitioning of the resulting components indicated that 88 per cent of the radioactivity was present in the long-chain base portion. At early time points (10 min, 20 min) the precursor was incorporated into ceramide and to a lesser degree into glucosyl-ceramide. During time intervals of 5 and 10 h, the specific activity values (d.p.m./μmol) for ceramide and glucosyl-ceramide decreased, while values for galactosyl-ceramide, containing either unsubstituted fatty acids (NFA) or α-hydroxy fatty acids (HFA), increased 50 and 30 per cent, respectively. Analysis of labelled ceramide at all time points studied (10 min-10 h) indicated that l -[¹⁴C]serine was incorporated onto the NFA type. This observation suggests that HFA-ceramide may not be the physiological precursor of HFA-galactosyl-ceramide. In this context, the postulated precursor roles of both ceramide and psychosine in the biosynthesis of brain cerebrosides are discussed.     

人工饲养下白暨豚行为的观察

在豢养条件下,白鱀豚的游泳除背向上正常姿态外,尚有侧游、仰游、滚游、跳跃、直立、浮卧和滑行多种型式。呼吸间隔时间不均匀,最短5秒,最长243秒,呼吸率为109—143次/小时。它的昼夜活动表现出明显的“激烈活动”和“平缓活动”两种状态,后者可能是一种休息方式。