scholarly journals Early Onset of Incubation by Wood Ducks

The Condor ◽  
2004 ◽  
Vol 106 (1) ◽  
pp. 182-186 ◽  
Author(s):  
Gary R. Hepp
Keyword(s):  
Breeding Season ◽  
Brood Parasitism ◽  
Early Onset ◽  
Egg Laying ◽  
Aix Sponsa ◽  
The Third ◽  
Wood Ducks ◽  
Incubation Periods

AbstractI examined onset of incubation in Wood Ducks (Aix sponsa) and evaluated the hypotheses that early onset improves hatchability, reduces brood parasitism, and shortens incubation periods. Most (21 of 22) females began incubating at night, a median of 4 days before egg laying ended. Nocturnal incubation bouts began 18 min before sunset, ended 15 min before sunrise, lasted 732 min each night, and totaled 47.2 hr before egg-laying ended (means). Nocturnal incubation did not begin earlier in the egg-laying period as the breeding season progressed, as would be expected if it improved hatchability of first-laid eggs. Early onset of incubation did not reduce brood parasitism. Females ended nocturnal incubation 35 min before egg laying began, the number of nights of incubation was not related to the number of parasitic eggs laid, and most (83%) nests were parasitized. In support of the third hypothesis, egg-laying females spending more nights incubating had somewhat shorter incubation periods.Inicio Temprano del Período de Incubación por Parte de Aix sponsaResumen. Examiné el inicio del período de incubación en patos de la especie Aix sponsa y evalué las hipótesis de que el comienzo temprano mejora la probabilidad de eclosión, reduce el parasitismo de la nidada y acorta el período de incubación. La mayoría (21 de 22) de las hembras comenzaron a incubar durante la noche, 4 días (mediana) antes que la puesta de huevos terminara. En promedio, la incubación nocturna comenzó 18 min antes del anochecer, terminó 15 min antes del amanecer, duró 732 min cada noche y totalizó 47.2 hr antes que la puesta de huevos terminara. La incubación nocturna no comenzó más temprano durante el período de puesta de huevos a medida que la estación reproductiva avanzó, como se esperaría si ésta mejorase la probabilidad de eclosión de los primeros huevos puestos. El inicio temprano de la incubación no redujo el parasitismo de la nidada. Las hembras terminaron la incubación nocturna 35 min antes que la puesta de huevos comenzara, el número de noches de incubación no se relacionó con el número de huevos de aves parásitas puestos y la mayoría (83%) de los nidos fueron parasitados. En apoyo a la tercera hipótesis, encontramos que las hembras que pusieron huevos y que pasaron más noches incubando tuvieron períodos de incubación un poco más cortos.

Update on the Status and Breeding Phenology of the Timberline Sparrow (Spizella breweri taverneri) in Alaska

Western Birds ◽  
2021 ◽  
Vol 52 (3) ◽  
pp. 252-260
Author(s):  
Claire M. Stuyck ◽  
Paul B. Leonard ◽  
Gerald V. Frost ◽  
Michelle L. S. Lake ◽  
Jeffrey D. Walters
Keyword(s):  
Breeding Season ◽  
Egg Laying ◽  
Alpine Tundra ◽  
Breeding Phenology ◽  
Active Nest ◽  
East Central ◽  
The Third ◽  
Betula Glandulosa ◽  
The Status ◽  
Spizella Breweri

In July 2020 we located 10 singing Timberline Sparrows [Spizella (breweri) taverneri] in the region of Gold Hill, Nutzotin Mountains, east-central Alaska. All birds were on southeast-facing slopes in the ecotone between subalpine scrub and alpine tundra, to which habitat breeding Timberline Sparrows seem narrowly confined. The population’s estimated density of 0.77 birds/km2 was similar to that at the time of its discovery in 1994. We located the first active nest of the Timberline Sparrow reported for Alaska, ~0.3 m above the ground in a shrubby resin birch (Betula glandulosa). An observation of young fledged on 11 or 12 July 2020 implies egg laying in the third week of June, later than the beginning of the breeding season of Spizella (breweri) breweri.

scholarly journals Patterns of Nest Attendance in Female Wood Ducks

The Condor ◽  
2000 ◽  
Vol 102 (2) ◽  
pp. 286-291 ◽  
Author(s):  
Chad A. Manlove ◽  
Gary R. Hepp
Keyword(s):  
Incubation Period ◽  
Body Mass ◽  
Nest Attendance ◽  
Aix Sponsa ◽  
Wood Ducks ◽  
Cavity Nesting ◽  
Data Loggers ◽  
Incubation Periods ◽  
Sources Of Variation ◽  
Period Data

AbstractWe examined sources of variation in incubation patterns among female Wood Ducks (Aix sponsa), and investigated the effect of female nest attentiveness on incubation period. Data were collected from 44 females (n = 911 days) using temperature data loggers to monitor nest attendance throughout incubation. Mean (± SE) incubation constancy was 86.9 ± 0.6% and incubation period averaged 30.9 ± 0.2 days. Females took an average of two bimodally-distributed recesses per day. Duration of recesses averaged 98.6 ± 3.4 min, but were shorter in the morning than in mid-day or late afternoon. Body mass of incubating females declined 0.68 ± 0.2 g day−1, but there was no relationship between constancy and early incubation body mass or weight change of females. Incubation constancy was not correlated with length of the incubation period. For most females, incubation constancy and recess frequency did not change as incubation progressed. The fact that incubating females only lost an average of 3% of body mass, and constancy was not related to either body mass or length of the incubation period, suggests that females were not constrained energetically. Finally, we propose that the combination of reduced predation risk and the need of neonates to be more functionally mature at hatching has selected for longer incubation periods in Wood Ducks and other cavity-nesting waterfowl.

scholarly journals Camptodactyly-Arthropathy-Coxa Vara-Pericarditis Syndrome Resembling Juvenile Idiopathic Arthritis: A Single-Center Experience from Southern Turkey

2021 ◽  
pp. 1-6
Author(s):  
Rabia Miray Kisla Ekinci ◽  
Sibel Balci ◽  
Haldun Dogan ◽  
Serdar Ceylaner ◽  
Celal Varan ◽  
...  
Keyword(s):  
Juvenile Idiopathic Arthritis ◽  
Pericardial Effusion ◽  
Early Onset ◽  
Joint Space ◽  
Coxa Vara ◽  
Single Center ◽  
The Third ◽  
Single Center Experience ◽  
Southern Turkey

Camptodactyly-arthropathy-coxa vara-pericarditis (CACP) syndrome, caused by biallelic pathogenic mutations in the <i>PRG4</i> gene, is characterized by early-onset camptodactyly, noninflammatory arthropathy, coxa vara deformity, and rarely, pericardial effusion. Herein, we report 3 patients with CACP syndrome from 2 unrelated families. All patients are female, born to consanguineous parents, and had camptodactyly since the first years of their lives. Two patients had a prior diagnosis of juvenile idiopathic arthritis. Hip changes were present in 2 patients, and 2 of 3 patients had undergone surgery for camptodactyly. Routine echocardiographic evaluations were normal during the 2-year follow-up. This paper represents the third study including CACP patients from Turkey. Clinically, all 3 patients resembled juvenile idiopathic arthritis cases and received unnecessary medication. There is also an ongoing need for improving awareness of CACP and an effective treatment focusing on the lubrication of the joint space in CACP patients.

The effect of maternal vitamin D supplementation in the third trimester on the incidence of early-onset sepsis in their newborns

2020 ◽  
Vol 9 (2) ◽  
pp. 74
Author(s):  
Prathapa Shetty ◽  
Manasee Deka ◽  
ManojKumar Yadav ◽  
Geeta Gathwala ◽  
Sunny Lohia ◽  
...  
Keyword(s):  
Vitamin D ◽  
Early Onset ◽  
Vitamin D Supplementation ◽  
Third Trimester ◽  
Maternal Vitamin ◽  
The Third ◽  
Early Onset Sepsis

The influence of nutrition on egg-production and longevity in unmated female body-lice (Pediculus humanus corporis: Anoplura)

Parasitology ◽  
1941 ◽  
Vol 33 (1) ◽  
pp. 40-46 ◽  
Author(s):  
A. J. Haddow
Keyword(s):  
Female Body ◽  
Egg Production ◽  
Egg Laying ◽  
The Body ◽  
Unmated Female ◽  
Pediculus Humanus ◽  
The Third ◽  
Significant Difference ◽  
The Mean ◽  
Body Lice

1. Isolated unmated female body-lice were worn in pillboxes between the skin and the clothes. They were kept constantly on the body but, by a simple device, groups of ten were permitted feeding periods of different length. These groups were fed for 4, 8, 12, 16, 20 and 24 hr. per day respectively. Another group of ten were never allowed to feed after the last moult.2. Some of the figures for egg yield were high. Lice in the 24 hr. group were able to maintain a rate of ten eggs per day for 4−5 days at a time.3. No significant difference in longevity or rate of egg-laying was found to exist between the 12, 16, 20 and 24 hr. groups nor between the 4 and 8 hr. groups but a pronounced and significant difference exists between the 8 and 12 hr. groups. Below 12 hr. there is a sharp fall in longevity and rate of egg production. The unfed group all died, without laying, on the third day.4. The rate of laying as shown by the mode increases progressively with increase in time allowed daily for feeding.5. With regard to the mean eggs per louse the position is less clear. It is felt that the 24 hr. group may differ significantly from the 12, 16 and 20 hr. groups but this is uncertain.

A study of the olfactory responses of insect parasites to the food plant of their host

Parasitology ◽  
1938 ◽  
Vol 30 (4) ◽  
pp. 523-528 ◽  
Author(s):  
W. H. Thorpe ◽  
H. B. Caudle
Keyword(s):  
Pinus Sylvestris ◽  
Adult Life ◽  
Egg Laying ◽  
Food Plant ◽  
Next Generation ◽  
Considerable Time ◽  
Olfactory Responses ◽  
The Third ◽  
Pine Trees ◽  
Insect Parasites

1. Pimpla ruficollis is a parasite of the pine shoot moth Rhyacionia (Evetria) buoliana Schiff. (Eucosmidae) which emerges from its host a considerable time before the next generation of larvae are ready for oviposition. It seems that during this period the parasites leave the pine trees and feed on the flowers of certain Umbelliferae and probably other plants. Only after 3 or 4 weeks do they return to the pine trees where the shoots now contain larvae ready for egg laying.2. It has been shown by means of olfactometer experiments that during this first period of the adult life, the parasites are repelled by the odour of oil of Pinus sylvestris. At this time the ovaries are very small and are probably not ready for the production of eggs. After the third or fourth week of life the females become attracted by the oil of P. sylvestris and the ovaries are now relatively large.3. Since Geraniol is known to be a constituent of certain conifers, this substance was also tested. It was, however, found to be invariably repellent to the parasites.4. There is some evidence that conclusions reached as a result of experiments with P. ruficollis also apply to the ophionine ichneumonid Eulimneria rufifemur.

scholarly journals Breeding biology of coppersmith barbet, Megalaima haemacephala (Müller, 1776)

2013 ◽  
Vol 31 ◽  
pp. 31-34
Author(s):  
Noor Jahan Sarker ◽  
M Firoj Jaman ◽  
Shariar Mustafa ◽  
Md Saidur Rahman
Keyword(s):  
Incubation Period ◽  
Breeding Season ◽  
Breeding Success ◽  
Brood Size ◽  
Botanical Garden ◽  
Egg Laying ◽  
Breeding Biology ◽  
Average Weight ◽  
Average Height ◽  
Average Depth

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 

A study of Canada geese, Branta canadensis, nesting on islands in southeastern Alberta

1970 ◽  
Vol 48 (2) ◽  
pp. 235-240 ◽  
Author(s):  
Kees Vermeer
Keyword(s):  
Egg Laying ◽  
Water Levels ◽  
Branta Canadensis ◽  
Canada Goose ◽  
Canada Geese ◽  
Uniform Spacing ◽  
Incubation Periods

Canada goose clutches situated on islands in Dowling Lake and Lake Newell, Alberta, were checked from laying to hatching. Egg-laying intervals averaged 1.87 days and incubation periods 26.8 days. The distribution of nests showed a significant deviation from randomness in the direction of uniform spacing. Causes of extensive hatching failure at Dowling Lake were predation and desertion. Predation by coyotes was facilitated by low water levels. A preference for nesting on islands appears to be a mechanism to counteract mammalian predation.

Factors influencing fledgling production in little penguins (Eudyptula minor)

2004 ◽  
Vol 31 (3) ◽  
pp. 339 ◽  
Author(s):  
C. Knight ◽  
T. Rogers
Keyword(s):  
Breeding Season ◽  
Egg Laying ◽  
Breeding Biology ◽  
Single Variable ◽  
Nesting Habitat ◽  
High Quality ◽  
Factors Influencing ◽  
Little Penguin ◽  
Significant Model

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.

Mortality and breeding failure of little penguins, Eudyptula minor, in Victoria, 1995 - 96, following a widespread mortality of pilchard, Sardinops sagax

2000 ◽  
Vol 51 (4) ◽  
pp. 355 ◽  
Author(s):  
Peter Dann ◽  
F. I. Norman ◽  
J. M. Cullen ◽  
F. J. Neira ◽  
A. Chiaradia
Keyword(s):  
At Risk ◽  
Breeding Season ◽  
Breeding Success ◽  
Egg Laying ◽  
First Year ◽  
Breeding Failure ◽  
Food Species ◽  
Intestinal Parasitism ◽  
Western Victoria

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.

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