Release Factors of Breeding Activities in Capercaillie (Tetrao urogallus) Hens

The present 7-year study was conducted on a capercaillie (Tetrao urogallus) lek. The study included four years of continuous monitoring of reproductive behaviour of capercaillie in spring and a 3-year study of hen-cock relationships. We used a factorial Correspondence Analysis (CA) to assess the relationship between variables such as weather, release activity and cock display behaviour, as well as the presence and activity of hens. The statistical correlations between these factors were also summarized, showing that: there is no direct relationship between daily activity of hens on the lek and photoperiod; the behavioural interactions between cocks, their spatial and territorial organization, on the one hand, and hen activity and receptivity on the other, are reinforced by reciprocal interactions between the sexes.     

Moults of wild Scottish ptarmigan, Lagopus mutus, in relation to sex, climate and status

The three annual moults and plumages of Scottish ptarmigan ( Lagopus mutus ) were studied from shot specimens but particularly from field observations. Cocks were ahead of hens in showing the grey autumn plumage but hens were ahead of cocks in turning white in winter. Although cocks were ahead in growing summer plumage, after late April the hens passed them. Ptarmigan on the same hill turned dark earlier in mild than in cold springs.     

Patterns and strategies of winter habitat selection in alpine capercaillie

Based on radio telemetry, habitat distribution of 32 individual capercaillie Tetrao urogallus was compared with habitat availability at various levels of scale At forest stand level, capercaillie preferred large patches of late succession stages, and selected for moderate canopy closure and high abundance of feeding trees Hens and cocks selected home ranges with high proportions of old forest, and range size was related to old forest fragmentation Winter survival was high independently of habitat selection In cocks, habitat use was affected by social spacing, home range size and use of old forest were age-dependent, and habitat composition of winter ranges indirectly related to survival and mating success in spring Topography influenced habitat selection, as the birds preferred gentle slopes At the landscape scale, the distribution of bilberry Vaccinium myrtillus was the key to capercaillie habitat use, indicating that habitat requirements in autumn and spring influenced selection of winter ranges The study confirms that capercaillie in central Europe select habitats according to structural features typical of the boreal forests of the species' main distribution range However, spatio-temporal variation in resource abundance at the landscape scale sets significant limits to suitability of alpine capercaillie habitats     

Mate choice by hen Red Grouse Lagopus lagopus with an excess of cocks—role of territory size and food quality

In a breeding population of Red Grouse the ratio of cocks to hens was about 2:1. Cocks with hens had bigger territories and richer feeding sites than unmated cocks. Despite this, the size of a cock's territory was inversely related to the level of nitrogen in his food. The idea that this was because cocks defend a territory just big enough to meet the pair's food requirements seemed inapplicable, since territories were much bigger than this. In addition, it was inferred that hens took longer to choose a cock on a part of the area that had relatively poor feeding sites. Whether hens chose the cock or his territory was uncertain, but both probably played a part.     

Habitat selection by capercaillie in summer and autumn: Is bilberry important?

The use of habitat by female and male adult capercaillie Tetrao urogallus during summer and autumn was studied by comparing the distribution of radio locations of birds with the availability of habitat at forest stand, home range and landscape level in an area of the Bavarian Alps, Germany. Capercaillie preferred forests with structural features typical of their main distribution range, the boreal forest: they selected large patches of old forest with moderate canopy cover of about 50%, and a well developed field layer with high proportions of bilberry Vaccinium myrtillus. Hens selected both home ranges and sites within home ranges in old forest. Ranges selected by cocks did not differ from availability in the study area, but they preferred old forest within their ranges. The size of home ranges was negatively related to bilberry cover both in hens and cocks. The distribution of bilberry also determined habitat use by capercaillie at the landscape scale. The study demonstrated that bilberry is the major determinant of the selection of habitat by capercaillie in landscapes with sparse and fragmentary cover of ericaceous shrubs, such as central Europe.     

Influence of environmental conditions on demand-feeding behaviour of gilthead seabream (Sparus aurata)

We studied the demand‐feeding behaviour was studied of gilthead seabream (Sparus aurata, L.) reared under either constant (25 ± 0.5°C, 12 : 12 L : D, control group) or natural (experimental group) temperature and photoperiod conditions during a period from winter to summer. Hourly demand‐feeding activity profiles were recorded using self‐feeding devices; these profiles showed that control group behaved entirely as a diurnal species, exhibiting no nightly activity and decreased demand rates in winter months. The experimental group did exhibit nightly activity (in incomplete darkness); this group also showed reduced demand rates in winter months, accompanied by a demand peak shift towards evening/night hours that followed the day's temperature peak of colder months.     

Two oscillators might control the locomotor activity rhythm of the high-altitude Himalayan strain of Drosophila helvetica

The properties of the pacemaker controlling the adult locomotor activity rhythm of the high-altitude Himalayan (haH) strain (Hemkund Sahib, 4121 m above sea level) of Drosophila helvetica are strikingly different from those of the low-altitude Himalayan (laH) strain (Birahi, 1132 m above sea level) of the same species. The haH strain has a unimodal activity pattern with a delayed peak occurring about 4.5 h after lights-on of the entraining light-dark (LD) cycle, while the laH strain has a bimodal activity pattern with the morning and evening peaks. It is rather unusual for a wild type strain of any Drosophila species to have a unimodal activity pattern during entrainment as observed in the haH strain. The single activity peak of the haH strain is regarded as a consequence of delayed morning peak merging with the evening one. Three experiments were performed to test this hypothesis. The first experiment examined whether the single activity peak could be dissociated into two components by LD cycles in which photoperiods varied from 10 to 16 h per 24 h. The haH strain again exhibited a unimodal activity pattern with a delayed peak in 10, 12, and 14 h photoperiods but a bimodal activity pattern in 16 h photoperiod. The laH strain had bimodality in 10 and 12 h photoperiods, unimodality in a 14 h photoperiod, but complete arrhythmicity in a 16 h photoperiod. In the second experiment, the haH flies were transferred from LD 16:8 to LL at 5 lux to confirm whether the bimodality of this strain in LD 16:8 cycles was not the result of masking by the long photoperiod of 16 h. Bimodality of the haH strain persisted in LL too; moreover, the morning component free-ran with period (tau) <24 h, while the evening component free-ran with tau>24 h. The third experiment examined the LL-induced splitting of activity peak of the haH strain. Flies were transferred from LD 12:12 cycles to LL at 0, 1, 5, and 15 lux. The haH strain was rhythmic in LL at 0 and 1 lux with a unimodal activity pattern. It was also rhythmic in LL at 5 lux, but the single activity peak was split into two discrete components; the morning component free-ran with tau<24 h, while the evening component free-ran with tau>24 h. This strain, however, was completely arrhythmic in LL at 15 lux. The laH strain was uniformly arrhythmic in LL at all levels of light intensity. These results suggest that the single but late activity component of the haH strain during entrainment appears to be the consequence of merging the delayed morning peak with the evening one as an adaptation to the environmental conditions at the altitude of origin of this strain, where these flies begin activity in the forenoon owing to non-permissible low temperature in the morning.     

Habitat partitioning in endangered Cantabrian capercaillie Tetrao urogallus cantabricus

The endangered Cantabrian capercaillie (Tetrao urogallus cantabricus) lives at the southern edge of tetraonids’ distribution range, in entirely deciduous forests. Its conservation planning has been always lek-centred. There is very little information about the specific habitat requirements of hens and broods, even though reproductive success appears to be a limiting factor. We analysed summer surveys from 1997 to 2004, carried out to estimate the reproductive success of the population. We compared the habitat characteristics at different spatial scales of hens with broods, broodless hens, and cocks in summer, with the better known spring habitat in display areas. Summer habitat showed higher proportion of open areas and was associated with more rugged zones at moderate spatial scales (78 ha) than spring habitat at display areas. Cocks and hens showed summer habitat partitioning; hens were associated with higher proportions of open and shrubby habitats. Furthermore, broodless hens preferred areas with higher slope variability than the display and summer areas preferred by cocks. These differences may reflect the sexual dimorphism of the species in reproductive role, energetic demands and conspicuousness. At larger spatial scales a previously developed habitat suitability model performed well to predict good brood-rearing areas. Hens with broods were located in the best-preserved areas in the range, mainly characterized by higher proportion of forest cover at a large (50 km²) scale. We suggest that these characteristics indicate refuge habitats where Cantabrian capercaillie can still breed successfully.     

Migratory restlessness in the Yellow-faced Honeyeater Lichenostomus chrysops(Meliphagidae), an Australian diurnal migrant

The Yellow-faced Honeyeater Lichenostomus chrysops is a diurnal migrant which covers short to moderate distances in eastern Australia. Recordings of locomotor activity of nine wild-caught Yellow-faced Honeyeaters kept under a simulated natural photoperiod in the laboratory over a period of 13 months showed that these birds exhibit a distinct seasonal pattern in hopping activity. Two major seasonal peaks of enhanced activity were observed. The first occurred during the time of autumn migration in March to July, while a second peak from September to December coincided roughly with spring migration. Daily activity patterns of Yellow-faced Honeyeaters showed two major peaks. The first peak ranged from the early morning hours to approximately early afternoon, while a second smaller peak was observed in the late afternoon. During their migratory periods in spring and autumn, the morning as well as the afternoon peaks were considerably higher than in months when Yellow-faced Honeyeaters do not migrate.     

Temporal pattern in foraging behaviour of the Indian pond heron,Ardeola grayii at Ratanpur,Chhattisgarh, India

In avian population, the biological clock is synchronized with the photoperiod as a significant time cue. However, information on feeding behaviour of the Indian Pond Heron, Ardeola grayii at Ratanpur, Chhattisgarh, India is not available. In present study we examined the effect of ‘time of the day’ and ‘photoperiod’ on daytime feeding behaviour of A. grayii at Ratanpur (85º17’E longitude and 22º3’N latitude), Chhattisgarh, India. The different feeding techniques of A. grayii, were recorded for two consecutive days each during long days (May and June 2014) and during short days (December 2014 and January 2015). One-way ANOVA (using SPSS 16.0) was applied to find out the effects of ‘photoperiod’ and ‘time of the day’ on daytime feeding activity with respect to frequency of feeding techniques. The rhythms in daytime feeding activity were evaluated using the Cosinor rhythmometry at 24 h and 12 h. The present study revealed that the A. grayii adopted three major techniques viz., slowly walking, probing and striking on which the slowly walking and striking was popularly used feeding technique as compared to the probing technique during the feeding. Moreover, the A. grayii is found to be bimodal viz., morning and evening type during both of long and short days. Furthermore, bird was more active during short day as compared to the long day.     

WINTER FEEDING ECOLOGY OF WIGEON ANAS PENELOPE AT THE OUSE WASHES, ENGLAND

Investigations on the feeding ecology of Wigeon were carried out in winter 1978–79 at the species' most important inland wintering habitat in Britain. The study area included 287 ha of grassland, about one-sixth of the Washes, which is grazed by cattle and sheep until late autumn. In winter the area is partly or fully flooded. The number of Wigeon increased to 11 200 in January but cold weather in February, with snow and frozen flood water, forced the birds to leave, only 600 staying in the reserve. In March up to 4000 birds were again present. The distribution of the population within the refuge depends on whether the habitat is dry pasture with only a few ponds, partly flooded, fully flooded or covered with snow and frozen flood water. Under dry or slightly wet conditions 98% of the Wigeon were grazing (October to January), while under partly flooded conditions (February and March) 42%, fed on water. With increasing water depth, upending was used by 13%, while 45% of the population moved to the barrier banks, grazing there in March. The feeding method can change within a few hours with increasing water depth. The diurnal activity pattern varies during the wintering period. A lower percentage of morning feeding occurred after flights back from feeding outside the refuge and under frozen conditions. The feeding activity was higher at mid-day with a slight decrease towards dusk. The average diurnal feeding activity was 71% (October to April), with a maximum of 90% in November. Wigeon feed diurnally and nocturnally. During a 24 h period in March they were foraging for 15 h 40 min; by day 81% of the time was spent feeding, while at night only 48%. Standing crop measurements showed that the biomass of green vegetation declined significantly outside enclosures due to Wigeon usage. Pasture land should be grazed at different intensities by cattle and sheep before the arrival of the ducks. Inland reserves should include such pasture together with some standing water where the birds are undisturbed. The use of inland pastures can compensate for the loss of coastal habitats.     

The moults of captive Scottish ptarmigan (Lagopus mutus)

The moults of captive Scottish ptarmigan were studied at Banchory, north-east Scotland from December 1968 to February 1971. In the autumn moult (June to September) which included the primaries, cock ptarmigan moulted earlier and more completely than hens. In the winter moult (September to February) hens moulted earlier and both sexes moulted more completely than in spring. In the spring moult (February to June) cocks moulted more rapidly to begin with but by mid-April hens had caught up and thereafter moulted at least as rapidly as cocks. When kept indoors at slightly higher temperatures ptarmigan grew more pigmented feathers during the winter moult. In a colder winter the birds became whiter than in a milder one. First-winter ptarmigan completed the winter moult later than older birds. Birds from the Cairnwell hills had more dark feathers in winter than those from the eastern Cairngorms. There was no correlation between the start or finish of egg-laying and moulting.     

Diurnal rhythms of body temperature, heart rate, and behaviour in the stanchioned adult Shiba goats

Using a data logger system, body temperature (dorsal subcutaneous temperature), heart rate, ingestive or ruminating behaviour and posture in adult Shiba goats tied to a stanchion were recorded automatically during 24 hours, to obtain basic information on the biological rhythms. A 600 g of usual ration mixed with hay cube, hay, beet pulp and wheat bran was fed twice a day (morning; 9:00-9:30, evening; 16:00-16:30). Animals kept under an artificial photoperiod (12L-12D, light period; 5:30-17:30) and about 10 degrees C room temperature. 1) Diurnal patterns of the above-mentioned items were recorded, mutual relationships relationships between these items were revealed. 2) The heart rate was higher after morning feeding, or during a light period and decreased gradually from midnight to early morning. Twice feeding greatly increased the heart rate. 3) The body temperature was lower in the early morning and increased gradually after morning feeding and showed the highest level during 1 to 1.5 hours after evening feeding. After that it decreased gradually till the early morning. 4) The numbers of jaw movement (bites/min) were a 70-90 bites in the ingestive behaviour and a 80-90 bites in the ruminating behaviour at dark period. 5) The total heart rate was a 110000 to 120000 beats/day, the total biting time was a 9.5 hours/day, and the mean standing time was a 9.3 to 11.7 hours/day. The standing time during light period (12 hours) was a 7.3 to 9.9 hours and that during dark period (12 hours) was a 1.8 to 2 hours.     

北京十渡自然保护区越冬黑鹳的种群生态调查

为了解黑鹳在北京地区越冬的生态特点,于2004年1月至2007年3月采用直接观察法对北京市拒马河自然保护区越冬黑鹳的数量、栖息地选择和取食规律进行了观察。结果表明拒马河流域已成为北京地区越冬黑鹳稳定的栖息地,种群数量超过20只。越冬聚群从11月开始,分群时间为次年2月。取食地相对集中,取食活动在越冬初期以上午和中午为主,中期以下午为主,末期则分为早晚两个时段。干旱和人为活动导致的适宜取食地减少是影响黑鹳生存的主要因素。     

Nest loss in capercaillie and black grouse in relation to the small rodent cycle in southeast Norway

Summary The relationship between nest loss in boreal forest grouse and the fluctuations in small rodents was studied at Varaldskogen in southeast Norway during 1979–1986, covering two complete rodent cycles. Nest loss in capercaillie (N=174) and black grouse (N=81) was calculated according to Mayfield (1975) based on nests from radio-equipped hens (N=77) and nests found by other methods (N=178). Small rodent density was measured by snap trapping during spring and autumn. Losses varied as predicted by the classical alternative prey hypothesis (Hagen 1952 and Lack 1954, as elaborated by Angelstam et al. 1984): high losses during rodent crash years (85.5% capercaillie, 51% black grouse), and smaller losses during peak years (54.5% capercaillie, 32.5% black grouse). Losses were inversely related to autumn abundance of rodents in capercaillie (P<0.05), but the correlation was not significant for black grouse (0.10<P<0.20). In capercaillie, the only species with an adequate sample for analysis, no relationship was detected between spring density of rodents and nest loss. Losses during the prepeak years were nearly as high as during crash years, a result inconsistent with the model. We conclude that the numerical response of predators to their cyclic main prey (i.e. small rodents) probably play a main role during the low phase and prepeak year, whereas the dietary shift is most important during the peak and crash year of the cycle.     

Two Oscillators Might Control the Locomotor Activity Rhythm of the High‐Altitude Himalayan Strain of Drosophila Helvetica

The properties of the pacemaker controlling the adult locomotor activity rhythm of the high‐altitude Himalayan (haH) strain (Hemkund Sahib, 4121 m above sea level) of Drosophila helvetica are strikingly different from those of the low‐altitude Himalayan (laH) strain (Birahi, 1132 m above sea level) of the same species. The haH strain has a unimodal activity pattern with a delayed peak occurring about 4.5 h after lights‐on of the entraining light‐dark (LD) cycle, while the laH strain has a bimodal activity pattern with the morning and evening peaks. It is rather unusual for a wild type strain of any Drosophila species to have a unimodal activity pattern during entrainment as observed in the haH strain. The single activity peak of the haH strain is regarded as a consequence of delayed morning peak merging with the evening one. Three experiments were performed to test this hypothesis. The first experiment examined whether the single activity peak could be dissociated into two components by LD cycles in which photoperiods varied from 10 to 16 h per 24 h. The haH strain again exhibited a unimodal activity pattern with a delayed peak in 10, 12, and 14 h photoperiods but a bimodal activity pattern in 16 h photoperiod. The laH strain had bimodality in 10 and 12 h photoperiods, unimodality in a 14 h photoperiod, but complete arrhythmicity in a 16 h photoperiod.

In the second experiment, the haH flies were transferred from LD 16∶8 to LL at 5 lux to confirm whether the bimodality of this strain in LD 16∶8 cycles was not the result of masking by the long photoperiod of 16 h. Bimodality of the haH strain persisted in LL too; moreover, the morning component free‐ran with period (τ) <24 h, while the evening component free‐ran with τ>24 h. The third experiment examined the LL‐induced splitting of activity peak of the haH strain. Flies were transferred from LD 12∶12 cycles to LL at 0, 1, 5, and 15 lux. The haH strain was rhythmic in LL at 0 and 1 lux with a unimodal activity pattern. It was also rhythmic in LL at 5 lux, but the single activity peak was split into two discrete components; the morning component free‐ran with τ<24 h, while the evening component free‐ran with τ>24 h. This strain, however, was completely arrhythmic in LL at 15 lux. The laH strain was uniformly arrhythmic in LL at all levels of light intensity. These results suggest that the single but late activity component of the haH strain during entrainment appears to be the consequence of merging the delayed morning peak with the evening one as an adaptation to the environmental conditions at the altitude of origin of this strain, where these flies begin activity in the forenoon owing to non‐permissible low temperature in the morning.     

Seasonal differences in habitat selection by Black Grouse Tetrao tetrix in the northern Pennines, England

Between-season differences in habitat use by Black Grouse Tetrao tetrix were studied on four moors in the northern Pennines between 1989 and 1992. Heather moor and bogs were preferred at all times of the year, apart from during the breeding season. In spring, large quantities of Cotton-grass Eriophorum vaginatum flowers were consumed, whereas in autumn and winter Heather Calluna vulgaris was more important. Enclosed fields on the edge of the moors were regularly used in autumn and winter by large flocks of cock birds, and hens were found in smaller groups. Where present, overgrazed grass moorland was generally avoided, apart from during the summer. Similarly, enclosed rough grazing allotments rich in rushes were favoured during the summer months by breeding hens and moulting cocks.     

The daily rhythms of melatonin and free fatty acids in goats under varying photoperiods and constant darkness

The purpose of the study was to explore parallel and divergent features of the daily rhythms of melatonin and plasma free fatty acids (FFA) in goats exposed to different lighting conditions. From these features, we attempted to analyze whether the endogenous melatonin rhythm plays any role in the maintenance of the FFA rhythm. Seven Finnish landrace goats were kept under artificial lighting that simulated the annual changes of photoperiod at 60°N (longest photoperiod, 18 h; shortest, 6 h). The ambient temperature and feeding regimen were kept constant. Blood samples were collected 6 times a year at 2 h intervals for 2 d, first in the prevailing light-dark (LD) conditions and then after 3 d in constant darkness (DD). In LD conditions, the melatonin levels always increased immediately after lights-off and declined around lights-on, except in winter (18 h darkness), when the low daytime levels were restored clearly before lights-on. The FFA levels also displayed a consistent rhythmicity, with low levels at night and a transient peak around lights-on. In DD conditions, the melatonin profiles were very similar to those found in the habitual LD conditions, but the rhythm tended to advance. The FFA rhythm persisted also in DD, and the morning peak tended to advance. There was an overall parallelism between the two rhythms, with one significant exception. In winter in LD conditions, the morning rise in FFA levels coincided with lights-on and not with the declining phase of melatonin, whereas in DD conditions, the FFA peak advanced several hours and coincided with the declining phase of melatonin. From this finding and comparisons of the calculated rhythm characteristics, i.e., phase-shifts, phase differences, and correlations, we conclude that the daily rhythm of FFA levels is most probably generated by an endogenous oscillator, primarily adjusted by dawn, whereas the melatonin rhythm in this species is regulated by an oscillator primarily adjusted by dusk. The results did not exclude a modulatory effect of melatonin on the daily FFA profiles, but melatonin secretion, alone, does not explain the patterns sufficiently.     

Seasonal changes in testicular contents and plasma concentrations of androgens in the desert gerbil (Gerbillus gerbillus)

Gerbils were caught in the Béni-Abbès area (Algeria). Testicular endocrine activity was highest in spring (testicular wt 298 +/- 10 mg; seminal vesicle wt 603 +/- 62 mg; testicular testosterone and androstenedione content 9.2 +/- 1.7 and 0.5 +/- 0.1 ng/testis; plasma testosterone 832 +/- 200 pg/ml). Values decreased in summer, were lowest in late summer and in autumn (84 +/- 17 mg; 40 +/- 14 mg; 0.20 +/- 0.06 and 0.02 +/- 0.01 ng/testis; 228 +/- 54 pg/ml, respectively) and increased again in winter (December-January). The onset of testicular endocrine activity was concomitant with the lowest temperatures and the shortest photoperiod; it increased when temperatures and daylength were increasing and began to decline when temperatures and photoperiod were still maximal. These seasonal changes in the endocrine activity of the testis of the gerbil differ from those of the sand rat inhabiting the same area.     

THE DISPLAY OF THE MANAKIN M. MANACUS

The "dancing rings" of Maracus m. trinitatus are almost invariably constructed in small clearings on the forest floor so that whippy saplings grow from their edges to form spring boards as the manakins ricochet back and forth across the rings.
Four sounds are made by both sexes, the snap, the "comb" noise, the growling "grrrrt" and the whirring wings. There is no satisfactory explanation of how these sounds are produced.
Apart from casual visits, the hens suddenly all appear at about the same time during the morning to dance with the cocks—one hen to a ring. The only exception to this was a pair that spent most of the day together at their ring.
Usually at about 9.30 a.m., all the cocks had drifted away, and then nearly every ring was occupied by a hen, dancing back and forth and producing, although not quite as loudly, the same sounds as produced by the cocks.
During the period the manakins were under observation (11 February to 16 March), no quarrelling took place among the cocks although their rings were often less than a foot apart; nor were the hens pursued or mated when they danced with the males. This probably indicates that the pairs using the dance rings were already mated or even with nests.