Hatching asynchrony in Burrowing Owls is influenced by clutch size and hatching success but not by food

AbstractGlucocorticoid hormones may mediate trade-offs between current and future reproduction. However, understanding their role is complicated by predation risk, which simultaneously affects the value of the current reproductive investment and elevates glucocorticoid levels. Here, we shed light on these issues in long-lived female Eiders (Somateria mollissima) by investigating how current reproductive investment (clutch size) and hatching success relate to faecal glucocorticoid metabolite [fGCM] level and residual reproductive value (minimum years of breeding experience, body condition, relative telomere length) under spatially variable predation risk. Our results showed a positive relationship between colony-specific predation risk and mean colony-specific fGCM levels. Clutch size and female fGCM were negatively correlated only under high nest predation and in females in good body condition, previously shown to have a longer life expectancy. We also found that younger females with longer telomeres had smaller clutches. The drop in hatching success with increasing fGCM levels was least pronounced under high nest predation risk, suggesting that elevated fGCM levels may allow females to ensure some reproductive success under such conditions. Hatching success was positively associated with female body condition, with relative telomere length, particularly in younger females, and with female minimum age, particularly under low predation risk, showing the utility of these metrics as indicators of individual quality. In line with a trade-off between current and future reproduction, our results show that high potential for future breeding prospects and increased predation risk shift the balance toward investment in future reproduction, with glucocorticoids playing a role in the resolution of this trade-off.

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Drought Induced Nepotistic Behaviour in Indian Black Ibis (Pseudibis papillosa) Inhabiting the Arid Zone of Rajasthan, India

Our Nature ◽

10.3126/on.v6i1.1654 ◽

2009 ◽

Vol 6 (1) ◽

pp. 47-51

Author(s):

K.C. Soni ◽

A.N. Sharma ◽

V.C. Soni

Keyword(s):

Clutch Size ◽

Kin Selection ◽

Hatching Success ◽

Arid Zone ◽

Breeding Birds ◽

Breeding Female ◽

Fledgling Success ◽

Reproductive Activities ◽

Nesting Activity

Drought induced nepotistic behaviour in the Indian Black ibis (Pseudibis papillosa) inhabiting the arid zone of Rajasthan has been studied. The aim of the present study is to know about any breeding abnormalities induced in the Indian Black ibis by seasonal tragedy like drought. As such the nepotistic behaviour is not found in the Black ibis (Pseudibis papillosa) during normal season. Drought induces a reduced nesting activity and nepotistic behaviour in the Black ibis inhabiting arid zone. The helper birds (Non breeding birds of the own species) become active during drought to assist breeding pairs of Black ibis in various reproductive activities like feeding of breeding female, nestlings, fledglings and defending the nests. The role of helpers in breeding activities of Black ibis during drought also improves their clutch size, hatching success and fledgling success. The significance of the drought induced nepotistic behaviour in Black ibis in view of Hamilton’s theory of kin selection has been discussed.Keywords: Nepotistic behaviour, Black ibis, arid zone, Rajasthan, Indiadoi: 10.3126/on.v6i1.1654Our Nature (2008)6:47-51

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Factors affecting egg viability and incubation time in prairie dabbling ducks

Canadian Journal of Zoology ◽

10.1139/z93-156 ◽

1993 ◽

Vol 71 (6) ◽

pp. 1146-1152 ◽

Cited By ~ 43

Author(s):

Todd W. Arnold

Keyword(s):

Clutch Size ◽

Incubation Time ◽

Egg Size ◽

Hatching Success ◽

Size Variation ◽

Negative Effects ◽

Factors Affecting ◽

Ambient Temperatures ◽

Weak Support ◽

Anas Clypeata

I determined hatching success for 328 dabbling duck (Anas spp.) eggs that were experimentally subjected to varying lengths of preincubation delay and then artificially incubated. Hatchability declined as unincubated eggs were exposed to longer preincubation delays. This effect was more pronounced at higher ambient temperatures and later in the nesting season, but did not vary with egg size or among duck species. These results are largely consistent with observed patterns of clutch-size variation among prairie-nesting waterfowl. Clutch size may be smaller later in the year and at lower latitudes owing to the negative effects of date and temperature on the ability of eggs to withstand preincubation delay. The timing of embryo mortality was bimodal, with peaks occurring during early development (<6 d) and just before hatching (>22 d); however, only early mortality was affected by preincubation delay. Eggs lost up to 2.6% of their initial mass as water vapor during preincubation delay, but the amount of water loss did not affect hatching success. Eggs subjected to preincubation delay required about 1 additional day to hatch. Incubation time was related to egg size in northern shovelers (Anas clypeata) and in all species combined, but not in blue-winged teal (Anas discors) or mallards (Anasplatyrhynchos). These data provide only weak support for the hypothesis that large eggs are costly because they take longer to hatch.

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Some Population Aspects of Common Tern Sterna hirundo Breeding in Algeria at a Small Mediterranean Island (East Coast of Algeria)

Ekológia (Bratislava) ◽

10.2478/eko-2021-0008 ◽

2021 ◽

Vol 40 (1) ◽

pp. 62-69

Author(s):

Mohamed Dhaya El-Hak Khemis ◽

Lamia Boutabia ◽

Kamilia Farhi ◽

Ali Elafri ◽

Asma Kahli ◽

...

Keyword(s):

Clutch Size ◽

Hatching Success ◽

Population Decline ◽

Shape Index ◽

Common Tern ◽

Small Island ◽

Sterna Hirundo ◽

Common Terns ◽

Mediterranean Island ◽

Mussel Shells

Abstract We present the first detailed study of population dynamics, breeding biology and egg measurement of Common Terns. During six years (from 2004 to 2009) of monitoring, from mid-May to mid-August, 74 Common Terns individual were recorded at Laouinet small island, El Tarf, northeast of Algeria, witha finite population growth rate that indicated an alarming population decline(λ = -0.62: Lambda). Sterna hirundo build its nests (n = 37) in the northeast at a mean distance of 7.58 m from the closest edge of rocks. The nests were closed and ovoid, constituted mainly of mussel shells Sandpit, stems and leaves. Incubation was performed by pairs of common tern and lasted 25.5 ±3.4 days. We recorded a clutch size of 1 to 3 eggs with mean clutch size of 2.45±0.65 (41.24±0.83 × 30.46±0.62 mm). The egg parameters (volume, mass, shape index) varied between the six years of the study. The egg volume (19.24±0.87) depended more on egg width (30.46±0.62), however the egg shape (0.73±0.20) depended negatively on the egg length (41.24±0.83) but not on the egg width. Our results also showed a stabilized hatching success and a best estimation of breeding success. The hatching success did not vary between years: 70.5% in 2004, 68.75% in 2005, 71.42% in 2006, 71.42% in 2007, 69.23% in 2008 and 69.23% in 2009.

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Clutch Size, Nest Size, and Hatching Asynchrony in Birds: Experiments with the Fieldfare (Turdus Pilaris)

Ecology ◽

10.2307/1938866 ◽

1982 ◽

Vol 63 (5) ◽

pp. 1389-1399 ◽

Cited By ~ 63

Author(s):

Tore Slagsvold

Keyword(s):

Clutch Size ◽

Hatching Asynchrony ◽

Nest Size

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Clutch parameters and reproductive success of a translocated population of red-crowned parakeet (Cyanoramphus novaezelandiae)

Australian Journal of Zoology ◽

10.1071/zo08069 ◽

2008 ◽

Vol 56 (6) ◽

pp. 389 ◽

Cited By ~ 4

Author(s):

Luis Ortiz-Catedral ◽

Dianne H. Brunton

Keyword(s):

Reproductive Success ◽

Clutch Size ◽

Brood Size ◽

Reproductive Output ◽

Hatching Success ◽

Natural Populations ◽

Reproductive Potential ◽

Breeding Pair ◽

Brood Rearing ◽

Breeding Seasons

At least four populations of the red-crowned parakeet (Cyanoramphus novaezelandiae) have been established via translocation within New Zealand over the last 40 years, but reproductive parameters of these populations have not been documented. We quantified differences in clutch parameters and reproductive success for a translocated population of this species on Tiritiri Matangi Island over two breeding seasons. Overall clutch parameters and estimates of reproductive success were consistent with reported values from natural populations. However, we found previously unreported differences in clutch size, hatching success and brood size between breeding seasons. The number of fledglings produced per breeding pair increased significantly from 1.4 to 3.4 fledglings during our two-year study. In contrast, egg volume and fertility per clutch did not vary during the same period. Overall, 7 eggs were laid per breeding pair but only 2.22 nestlings fledged, representing a 63.8% loss of initial reproductive potential. Losses during the incubation stage were caused by partial and total hatching failure, whereas starvation of nestlings caused all losses during the brood-rearing stage. Hatching success during our study was lower than that reported for wild populations of this and other parrot species, and remained lower even during the most productive breeding season. We found no cases of predation on eggs or nestlings during our study despite the presence of native and exotic avian predators on Tiritiri Matangi Island. We show that clutch size, brood size and changes in loss between breeding seasons are determinants of reproductive output in translocated red-crowned parakeet and also that reproductive output can vary greatly between breeding seasons. Finally, if reduced hatching success is the result of small founder size, management of parakeets should consider the movement of larger and more genetically diverse flocks.

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Temperature-sex determination in Podocnemis expansa (Testudines, Podocnemididae)

Iheringia Série Zoologia ◽

10.1590/s0073-47212011000200001 ◽

2011 ◽

Vol 101 (3) ◽

pp. 151-155 ◽

Cited By ~ 2

Author(s):

Kelly Bonach ◽

Adriana Malvasio ◽

Eliana R. Matushima ◽

Luciano M. Verdade

Keyword(s):

Sex Determination ◽

Success Rate ◽

Incubation Period ◽

Clutch Size ◽

Hatching Success ◽

Incubation Temperature ◽

Small Sample ◽

Mato Grosso ◽

Araguaia River ◽

Podocnemis Expansa

This study has been carried out at the central region of the Araguaia river on the border between the states of Goiás and Mato Grosso in the Brazilian Amazon Basin from September to December 2000. We recorded temperature fluctuation, clutch-size, incubation period and hatching success rate and hatchlings' sex ratio of five nests of Podocnemis expansa (Schweigger, 1812). Despite the relatively small sample size we infer that: a) nests of P. expansa in the central Araguaia river have a lower incubation temperature than nests located further south; however, incubation period is shorter, hatching success rate is lower and clutch-size is larger; b) Podocnemis expansa may present a female-male-female (FMF) pattern of temperature sex-determination (TSD); c) thermosensitive period of sex determination apparently occur at the last third of the incubation period; and, d) future studies should prioritize the relationship between temperature variation (i.e., range and cycle) and embryos development, survivorship and sex determination.

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Variation in incubation length and hatching asynchrony in Eastern Kingbirds: Weather eclipses female effects

The Auk ◽

10.1093/ornithology/ukab031 ◽

2021 ◽

Author(s):

Samantha M Gillette ◽

Amanda L Klehr ◽

Michael T Murphy

Keyword(s):

New York ◽

Clutch Size ◽

Egg Laying ◽

Hatching Asynchrony ◽

Ambient Temperatures ◽

Temperature And Precipitation ◽

Incubation Periods ◽

Tyrannus Tyrannus ◽

Eastern Kingbird ◽

Small Clutch

Abstract Incubation length and hatching asynchrony are integral elements of the evolved reproductive strategies of birds. We examined intra- and interpopulation variation in both traits for Eastern Kingbird (Tyrannus tyrannus) populations from New York (NY), Kansas (KS), and Oregon (OR) and found that both incubation length and hatching asynchrony were not repeatable among females, after controlling for a repeatable trait, clutch size. Instead, incubation length and clutch size were influenced by ambient temperature and precipitation. Incubation length exhibited the same median (15 days) and range (13–17 days) at all sites. Model selection results indicated that incubation periods for the smallest and largest clutches were longer in NY than KS when rain was frequent throughout incubation, in replacement nests, and likely when ambient temperatures were low during egg-laying. Full hatching usually required 2 days (but up to 3), with synchronous hatching associated with small clutch sizes, short incubation periods, frequent rain during the egg-laying period, and low ambient temperatures during the first half of incubation. Nestling starvation was uncommon (5–9% of nestlings monitored) and not associated with greater hatching asynchrony. These results indicate that while clutch size, a repeatable female trait, contributed to variation in incubation length and hatching asynchrony in Eastern Kingbirds, weather was a greater source of variation, especially for incubation length.

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Seasonality, Clutch Size, and Hatching Success in the Cedar Waxwing

The Auk ◽

10.1093/auk/96.1.196 ◽

1979 ◽

Vol 96 (1) ◽

pp. 196-198

Author(s):

Charles F. Leck ◽

Frederic L. Cantor

Keyword(s):

Clutch Size ◽

Hatching Success ◽

Cedar Waxwing

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A Neglected Cost of Brood Parasitism: Egg Punctures by Shiny Cowbirds During Inspection of Potential Host Nests

The Condor ◽

10.1093/condor/104.2.407 ◽

2002 ◽

Vol 104 (2) ◽

pp. 407-412 ◽

Cited By ~ 6

Author(s):

Viviana Massoni ◽

Juan Carlos Reboreda

Keyword(s):

Survival Rate ◽

Clutch Size ◽

Brood Parasitism ◽

Hatching Success ◽

Egg Survival ◽

Potential Host ◽

Molothrus Bonariensis ◽

Nest Desertion ◽

The Impact ◽

Free Area

Abstract Parasitized hosts of the Shiny Cowbird (Molothrus bonariensis) suffer several costs, and among the most important is the loss of eggs through egg punctures inflicted by the parasite. Unparasitized nests also have eggs damaged by cowbirds, but researchers usually ignore these losses. To quantify this cost we compared three groups of nests of the Yellow-winged Blackbird (Agelaius thilius): parasitized and unparasitized nests from an area used by Shiny Cowbirds, and unparasitized nests from an area not used by the parasite. Because cowbirds puncture eggs as soon as the first host eggs are laid, we calculated the clutch size only for those nests found during construction. Unparasitized nests in the area used by cowbirds had lower egg survival rate and hatching success and higher probability of nest desertion than unparasitized nests in the cowbird-free area. Our results indicate that one must consider egg punctures at unparasitized nests to avoid underestimating the impact of parasitism. Un Costo Ignorado del Parasitismo de Cría: Perforación de Huevos por Molothrus bonariensis durante la Inspección de Potenciales Nidos de Hospedadores Resumen. Los hospedadores de Molothrus bonariensis sufren varios costos, entre los que se destaca la pérdida de huevos debida a perforaciónes hechas por el parásito. Los nidos no parasitados también tienen huevos perforados por M. bonariensis, pero estas pérdidas son normalmente ignoradas. Para cuantificar este costo comparamos tres grupos de nidos de Agelaius thilius: nidos parasitados y no parasitados de un área usada por M. bonariensis, y nidos no parasitados de un área no utilizada por el parásito. Como los parásitos perforan los huevos del hospedador tan pronto como éstos son puestos, el tamaño de puesta se calculó utilizando únicamente los nidos encontrados durante su construcción. Los nidos no parasitados del área visitada por los parásitos tuvieron menor supervivencia de sus huevos durante la incubación, menor éxito de eclosión y mayor probabilidad de ser abandonados que los nidos no parasitados del área libre de parásitos. Los resultados obtenidos indican que deben considerarse las perforaciones de huevos en nidos no parasitados para evitar subestimar el impacto del parasitismo.

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