The Breeding Season of Captive Barbary Doves, Streptopelia risoria, at Helena Valley, Western Australia

1974 ◽  
Vol 1 (1) ◽  
pp. 85 ◽  
Author(s):  
SJJF Davies

The breeding season of captive barbary doves was studied near Perth, W.A., between 1966 and 1971. It was found that the birds ceased breeding in May and began again in late July. The interval from pair formation to egg-laying was long early in the breeding season, shortest in early summer, and very long in autumn.

2005 ◽  
Vol 65 (3) ◽  
pp. 459-467 ◽  
Author(s):  
A. C. M. Horn ◽  
A. Achaval ◽  
D. M. Zancan

Morphological changes in the sexual organs of the pulmonates were observed throughout a year and correlated with reproductive-cycle periods. Reproductive-organ weights of the snail Megalobulimus abbreviatus were recorded seasonally and gonad sections were analyzed morphologically. The weights were used to obtain the organosomatic index. Mean oocytic diameter and oocytic maturation index were based on gonad sections. It was concluded that M. abbreviatus is an iteroparous snail whose annual reproductive cycle is characterized by mating and egg laying throughout spring and early summer, and also by reproductive system preparation, occurring over the remainder of the summer until the end of winter, for a new breeding season.


1988 ◽  
Vol 66 (6) ◽  
pp. 1334-1341
Author(s):  
John Atle Kålås

Data on live birds and previously published data reveal that female Dotterel (Charadrius morinellus) were on average larger than males for all measurements. However, sexual dimorphism on the basis of size appears weaker than expected when Dotterel are compared with closely related monogamous species. Female museum specimens have less disrupted (brighter) plumage colours than males, and dimorphism in plumage is more pronounced than it is in size. A discriminant analysis based on plumage characters did not separate the sexes totally, however. Females moult earlier in the spring than males, but summer plumage is still not fully developed for all females by the first period of pair formation, suggesting that female plumage is most important in reproduction only after the first clutch is complete. No significant differences were evident in wing length and plumage colour between 1882–1917 and 1957–1982. Time–activity studies on the polyandrous Dotterel during the arrival, prelaying, and egg-laying periods showed small differences between the sexes in the amount of time devoted to agonistic and courtship behaviour. Data from prelaying periods showed no difference between the sexes as to who initiates bouts of courtship and agonistic behaviour. The behaviour of paired birds was highly synchronized. Three hypotheses on the slight sexual dimorphism in size and plumage of this polyandrous species are presented and discussed.


1992 ◽  
Vol 19 (4) ◽  
pp. 405 ◽  
Author(s):  
NJ Gales ◽  
AJ Cheal ◽  
GJ Pobar ◽  
P Williamson

The Australian sea-lion, Neophoca cinerea, has a 17-18-month breeding cycle on islands off the west coast of Western Australia. Buller, North Fisherman and Beagle Is are the main pupping sites, with several very small colonies (n> 3) at the Abrolhos Is. The 4-5-month pupping seasons are synchronised at North Fisherman and Beagle Is, but the sea-lions from Buller I. breed one month later and those from the Abrolhos Is two months earlier. Pup production and pup mortality were highly variable between seasons over which observations were recorded: 129 pups were born at the main breeding sites in early 1988, the mortality in the first five months was 7.1%, whereas 181 pups were born in late 1989 of which 24.3% died. Pups remain in the vicinity of their natal islands for the first 4-5 months of life before leaving, perhaps on foraging trips, with their mothers. Most return to their natal island, although others haulout on islands up to 27 km away. Some male N. cinerea congregate in bachelor colonies on islands adjacent to the Perth metropolitan region during the non-breeding season and migrate up to 280 km north each breeding season. The status of the isolated, west-coast N. cinerea population is unknown. The current high level of human pressure on sea-lion terrestrial habitats and their food resources indicate a need for further monitoring of this species.


2013 ◽  
Vol 31 ◽  
pp. 31-34
Author(s):  
Noor Jahan Sarker ◽  
M Firoj Jaman ◽  
Shariar Mustafa ◽  
Md Saidur Rahman

Breeding biology of the Coppersmith barbet, Megalaima haemacephala (Müller, 1776) was carried out between February, 2006 and January, 2007 at Sharawardy Uddyan, Ramna Park, Curzon Hall and National Botanical Garden. The breeding season started from December and ended in June. In total 20 nests were observed, of which 10 nests were studied in details in four study areas. The coppersmith barbet mostly preferred to make holes on the branches of koroi (Albizzia procera) for nesting. Egg laying started on 15th February in the study areas. Average height of nests from the ground was 9.7m and average depth and diameter of the holes was 29.20cm and 4.46cm respectively. New holes were constructed yearly or the old one was reused. Both the sexes took part in incubation of eggs, brooding and feeding to the nestlings. A total of 30 eggs were laid in 10 nests. Clutch size varied from 2 – 4 eggs (average: 3 eggs). Among them, 20 (66.67%) eggs were hatched and the rest 10 (33.33%) were unhatched and lost. Average incubation period was 14 days. The male and the female incubated the eggs for an average of 27.44 minutes/ hours and 32.56 minutes/ hours, respectively. Average number of nestlings (brood size) per nest was 2. Out of 20 nestlings, 16 left their nests successively. The breeding success was 53.33% in relation to the number of eggs laid and 80% in relation to nestlings hatched. The average weight of eggs and nestlings was 3.59g and 9.33g, respectively. The main causes of loss of the eggs and nestlings were human interference, predation and ectoparasitic infections. Insects and fruits were fed to the nestlings by their parents.DOI: http://dx.doi.org/10.3329/ujzru.v31i0.15397Univ. j. zool. Rajshahi Univ. Vol. 31, 2012 pp. 31-34 


The Auk ◽  
1979 ◽  
Vol 96 (1) ◽  
pp. 56-67 ◽  
Author(s):  
Shoshana Ashkenazie ◽  
Uriel N. Safriel

Abstract Pair formation of Calidris pusilla near Barrow, Alaska occurs 3-6 days after the territory is established. The pair is then engaged in nest scraping displays during 2-3 days, in which 10-12 scrapes are made by the male and examined by the female. Eventually 2-3 scrapes are lined by the female, and in one of these the first egg is laid 4-6 days after pairing. During the egg-laying period further lining is performed by the female and partial incubation takes place by both sexes. Continuous incubation commences 8 h prior to laying of the 4th egg. Male and female alternate in incubation: in the first 2 days a turn lasts 3-5 h, and the duration gradually increases up to 13-14 h during the 2nd week. Long incubation turns reduce the number of approaches to the nest and may therefore reduce the chances of it being discovered by predators. The incubating bird is intermittently engaged in egg-rolling and in camouflaging the nest by bending adjacent grass blades over its back, and is constantly alert. The off-duty bird may feed 2-3 km away from the nest. The eggs hatch after 20 days of incubation, all within 1 day. Females desert the family 2-8 days after hatching: they desert late if hatching is early, and early if hatching is late in the season. After female departure the family moves from the nesting territory, typically in a high-centered polygonal area, to establish a home range as far as 2-3 km away, often in a low-centered polygonal area. During the first 6-8 days after hatching, the male prepares each evening a scrape for night brooding. After fledging, the male and young join wandering flocks.


2004 ◽  
Vol 31 (3) ◽  
pp. 339 ◽  
Author(s):  
C. Knight ◽  
T. Rogers

An eight-year study was conducted on the breeding biology of the little penguin population at Lion Island. Forwards-selection Poisson regressions were used to determine whether variables such as year, date of lay, years since banding of each parent (indicator of age) and habitat influenced the fledgling numbers and average fledgling weight for adult pairs. 'Date of lay' provided the most significant model of fledgling numbers, while 'habitat' and 'year' as single-variable models also significantly influenced fledgling numbers. 'Date of lay' provided the most significant model of average fledgling weight. Future monitoring of the Lion Island colony therefore should focus on monitoring egg laying at the start of the breeding season, and maintaining high-quality nesting habitat.


2000 ◽  
Vol 51 (4) ◽  
pp. 355 ◽  
Author(s):  
Peter Dann ◽  
F. I. Norman ◽  
J. M. Cullen ◽  
F. J. Neira ◽  
A. Chiaradia

In May 1995, numbers of little penguins, Eudyptula minor, coming ashore declined at Phillip Island and St Kilda concurrently with deaths of many penguins in western Victoria and a massive mortality of one of their food species (pilchard) throughout southern Australia. Among 1926 dead penguins reported were 131 banded birdsrecovered from Phillip Island (86% adults and 14% first-year birds), 26 from Rabbit Island and six from St Kilda. The number of banded penguins found dead per number of adult Phillip Island birds at risk was 2.3% in 1995 compared with an annual mean of 0.7% for 1970–93. Of 29 corpses autopsied, at least 26 died of starvation associated with mild–severe gastro-intestinal parasitism. Following the pilchard mortality, egg-laying by penguins in the subsequent breeding season (1995–96) was ~2 weeks later than the long-term mean and 0.3 chicks were fledged per pair compared with the long-term mean of 1.0. Unlike previous years, few penguins were recorded in Port Phillip Bay in September–October 1995, a period when pilchard schools were infrequently seen. It is concluded that the increase in penguin mortality in northern Bass Strait and the significant reduction in breeding success were associated with the widespread pilchard mortality.


2018 ◽  
Vol 58 (12) ◽  
pp. 2269 ◽  
Author(s):  
D. Real ◽  
C. M. Oldham ◽  
A. van Burgel ◽  
E. Dobbe ◽  
J. Hardy

Tedera (Bituminaria bituminosa C.H Stirt. vars. albomarginata and crassiuscula) is a traditional forage species for goats in the Canary Islands, Spain. It has agronomic characteristics ideally suited to Mediterranean-like climates that allows it to provide high quality green forage for grazing animals during summer and autumn. It can be used to extend the growing season into late spring and early summer and/or to reduce or eliminate the need for expensive hand feeding of grain and hay to sheep to fill the ‘feed gap’ during the dry season in southern Australian farming systems. Three sheep grazing experiments were carried out with the objective to evaluate sheep production during summer and autumn with tedera as the sole diet. A 3-ha site at Dandaragan, Western Australia was grazed during the summer and autumn of 2014–2015 and 2016 and a 2.4-ha site was grazed at Kojonup, Western Australia during the same period in 2016. At each site, two grazing treatments were evaluated, continuous grazing and rotational grazing with six plots (14 days of grazing and 70 days of recovery). The first hypothesis tested was that tedera plants would not survive continuous grazing during summer and autumn. The second hypothesis tested was that without hand feeding, 10 dry sheep equivalents/ha would be able to at least maintain weight and condition score during summer and autumn. The third hypothesis tested was that rotational grazing would improve the production of the sheep (liveweight and condition score) compared with continuous grazing. The first hypothesis was rejected, the population of tedera plants did not significantly decline due to being continuously grazed during summer and autumn. The second hypothesis was confirmed, at the three experimental sites, 10 dry sheep equivalents/ha were able to at least maintain weight and condition score without any hand feeding. The third hypothesis was partially rejected; continuous grazing had a better performance of the sheep than rotational grazing. However, the rotational grazing plots had more tedera on offer in the remaining grazing plots in the rotation with the potential for a longer grazing time. These three experiments clearly demonstrate that tedera can be used to reduce or eliminate expensive hand feeding during summer and autumn using the simplest and least expensive grazing management; continuous grazing.


1975 ◽  
Vol 15 (73) ◽  
pp. 183 ◽  
Author(s):  
TW Knight ◽  
CM Oldham ◽  
JF Smith ◽  
DR Lindsay

Data on reproductive losses in 55 flocks involving 25,571 ewes in south Western Australia are presented. The important source of reproductive wastage was that associated with ewes that mated but failed to lamb. The magnitude of the loss (28-30 per cent) did not vary significantly among flocks joined at different times of the breeding season (November-March), or between maiden and older ewes. Losses from birth to tailing were only about 50 per cent of those associated with dry ewes. Failure to mate was not a major source of loss. Two methods of detecting dry ewes were assessed, the doppler technique and the use of vasectomised rams after fertile mating. The accuracy of detection was 82-88 per cent for the doppler technique and 90 per cent for the vasectomised rams. It was concluded that the use of vasectomised rams is the cheaper and more efficient technique.


1988 ◽  
Vol 15 (2) ◽  
pp. 149 ◽  
Author(s):  
PA Woolley

The ningbing antechinus is a species of small dasyurid marsupial found in the Kimberley region of Western Australia. Observations on reproduction have been made on newly captured and laboratory maintained specimens. The breeding season is short and mating occurs in June. The young are born after a long gestation, estimated to be between 45 and 52 days, in late July and early August. They are weaned in November when about 16 weeks old and they reach sexual maturity at 10-11 months, in the first breeding season after birth. Both males and females are potentially capable of breeding in a second season.


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