Spatial differences in breeding success in the pied avocet Recurvirostra avosetta: effects of habitat on hatching success and chick survival

AbstractIn 2018 and 2019, the breeding success of two Common Tern colonies on artificial lakes near the River Sava in Zagreb, Croatia, was studied. The colonies were visited weekly from May to July and we collected data on phenology, number of breeding pairs, clutch size as well as egg and chick survival. We also conducted a comparison between early and late breeders. Hatching and fledging success was within previously observed ranges, apart from a low hatching success on Siromaja in 2019. The smaller colony on Siromaja had a higher productivity in both years than the colony on Rakitje, although in 2018 an avian pox virus killed much of the late chicks on Rakitje. Early breeders seem to have had higher hatching success and average clutch size. Furthermore, a greater proportion of them managed to hatch all their eggs compared to late breeders, but the differences were not statistically significant. Our study provided baseline data for future monitoring of phenology and breeding success with regard to the management of breeding colonies.

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Smålommens Gavia stellata häckningsframgång i artens svenska kärnområde

Ornis Svecica ◽

10.34080/os.v12.22452 ◽

2002 ◽

Vol 12 (1–2) ◽

pp. 1-33

Author(s):

Börje Dahlén ◽

Mats O G Eriksson

Keyword(s):

Breeding Success ◽

Large Scale ◽

Annual Variation ◽

Hatching Success ◽

Coniferous Forests ◽

Chick Survival ◽

Freshwater Lakes ◽

Early Start ◽

Regional Factors

We investigated the breeding success of a Red-throated Diver Gavia stellata population of approximately 70 pairs during ten seasons, 1991–2000, in a 1820 km2 study area, dominated by coniferous forests and mires in Malung, Dalarna in Central Sweden. The majority of the pairs bred in tarns smaller than 1.0 ha and foraged in larger freshwater lakes or rivers up to a distance of 4.6 km. Average breeding success was 0.76 “large” chicks per pair and year, with a declining trend over the study period accompanied by a decline in the proportion of broods with two “large” chicks. Breeding success was higher in seasons with an average early start of incubation and could be related to higher hatching success and survival of chicks. Predation during incubation was probably an important reason for breeding failures, and abandoning or change of breeding tarns were related to breeding failures. The annual variation of the percentage of broods with two “large” chicks was synchronised between pairs foraging at different fishing lakes, which indicates the influence of some large-scale regional factors linked to the availability of food. Chick survival in two-chicks broods was significantly lower than in one-chick broods. The declining trend in breeding success is an incitement for future monitoring, and any link to impaired foraging conditions needs to be more closely addressed.

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Does the vicinity of the Black-Headed Gull colony (Chroicocephalus ridibundus) increase the breeding success of the Common Tern (Sterna hirundo) on the islands of the middle Vistula?

Studia Ecologiae et Bioethicae ◽

10.21697/seb.2018.16.4.04 ◽

2018 ◽

Vol 16 (4) ◽

pp. 43-50

Author(s):

Dariusz Bukackiński ◽

Monika Bukacińska ◽

Milena Grabowska

Keyword(s):

Hatching Success ◽

Single Species ◽

Common Tern ◽

Egg Mass ◽

Chick Survival ◽

Effective Protection ◽

Vistula River ◽

Nesting Site ◽

The Common ◽

The City

We conducted our study in the Common Tern colony (STH) located on an island in the middle Vistula River course, at the height of the city of Dęblin (km 393–394 of the waterway), in 2017. Our goal was to investigate some aspects of the biology and reproductive ecology of this species. Due to the fact that STH breeds both in single-species as well as in two- or multi-species colonies, in associations with Little Terns (Sternula albifrons), Black-Headed Gulls (Chroicocephalus ridibundus) (LAR) and/or Mew Gulls (Larus canus), we wanted to investigate whether the neighborhood of other species (in this case LAR) affected hatching success and chick survival in STH. Our results clearly show that the presence of breeding terns in the neighborhood of the LAR colony was not accidental and/or caused by the lack of space on the island and/or the possibility of nesting elsewhere. The height of nesting site, type of nesting habitat, clutch size, mean egg volume and mean egg mass of these STH pairs did not differ significantly from those that formed a single species colony, on the same island but several hundred meters away. However, STH nests in the neighborhood of the LAR colony were established much earlier and both the hatching success and chick survival of STH during the early-chick stage were twice as high. Thus, we can conclude that the LAR colony could provide an effective protection against predation of crows, magpies and gulls, dangers which accounted for the vast majority of STH nest failures in the year of our study.

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Creamy-Bellied Thrush Defenses Against Shiny Cowbird Brood Parasitism

The Condor ◽

10.1093/condor/107.4.788 ◽

2005 ◽

Vol 107 (4) ◽

pp. 788-796 ◽

Cited By ~ 3

Author(s):

Andrea A. Astie ◽

Juan C. Reboreda

Keyword(s):

Brood Parasitism ◽

Hatching Success ◽

Simultaneous Presentation ◽

Control Model ◽

Nest Attendance ◽

Chick Survival ◽

Molothrus Bonariensis ◽

Egg Ejection ◽

Cowbird Parasitism ◽

Recognition Errors

AbstractWe studied Creamy-bellied Thrush (Turdus amaurochalinus) defenses against brood parasitism by Shiny Cowbirds (Molothrus bonariensis). Shiny Cowbirds decrease the reproductive success of Creamy-bellied Thrushes, and having historical habitats and ranges that overlap, we expected that thrushes possess antiparasitic defenses. We analyzed nest attendance during prelaying, laying and incubation; responses to the presentation of a model of a female cowbird or a control species close to the nest; nest abandonment associated with parasitism; and responses to experimental parasitism with white or spotted cowbird eggs (with or without the simultaneous presentation of a female cowbird model). Nest attendance was 58%–68% during prelaying and 83%–90% during laying and incubation. Thrushes had a shorter latency in returning near the nest and visited nests more frequently when we presented the cowbird model than the control model. The frequency of abandonment of parasitized nests was low and was not temporally associated with parasitism. Thrushes ejected white eggs more frequently than spotted eggs when parasitism was associated with the presentation of the cowbird model, but there were no differences when the model was absent. Our results indicate that Creamy-bellied Thrushes recognize cowbirds as a threat and eject white but not spotted cowbird eggs. We postulate that the low impact of cowbird parasitism on thrush hatching success and chick survival and the likelihood of recognition errors when parasite eggs resemble host eggs may have prevented the evolution of egg ejection in this host.

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Costs of Egg Punctures and Parasitism by Shiny Cowbirds (Molothrus Bonariensis) at Creamy-Bellied Thrush (Turdus Amaurochalinus) Nests

The Auk ◽

10.1093/auk/123.1.23 ◽

2006 ◽

Vol 123 (1) ◽

pp. 23-32 ◽

Cited By ~ 3

Author(s):

Andrea A. Astié ◽

Juan C. Reboreda

Keyword(s):

Reproductive Success ◽

Hatching Success ◽

Nest Survival ◽

Egg Laying ◽

Chick Survival ◽

Egg Survival ◽

Lower Survival Rate ◽

Molothrus Bonariensis ◽

Primary Determinant ◽

The Cost

AbstractMost studies on cowbird parasitism have focused on its effects on parasitized nests, whereas few have considered the costs at nests that cowbirds visit but at which they do not lay eggs. Shiny Cowbirds (Molothrus bonariensis) peck and puncture host eggs both in nests where they lay eggs and in unparasitized nests. We analyzed the effect of egg punctures in unparasitized and parasitized nests of a large host, the Creamy-bellied Thrush (Turdus amaurochalinus; hereafter “thrush”), as well as the costs of Shiny Cowbird eggs and chicks in this host’s nests. We determined thrush egg survival, hatching success, and chick survival in successful nests, and nest survival during the egg and nestling stages. Frequency of parasitism was 60%, and its intensity 1.6 ± 0.1 eggs nest−1. Number of host eggs punctured was positively associated with intensity of parasitism. The host’s eggs were frequently punctured in parasitized nests (71%) and in unparasitized nests (42%). Egg punctures reduced the number of eggs at hatching in 23% and 49% of unparasitized and parasitized nests, respectively. Nests with egg punctures had a lower survival rate than nests without them, but nest survival was not associated with parasitism. Presence of a Shiny Cowbird egg was associated with a decrease in the hatching success of host eggs, but presence of a Shiny Cowbird chick did not have any detrimental effect on either the survival and growth rate of host chicks in successful nests or the survival of the whole nest. Our results show that egg punctures were the primary determinant of thrush reproductive success. Consequently, comparison of unparasitized and parasitized nests gives an incomplete estimation of the effects of Shiny Cowbirds on host reproductive success, because the cost of egg punctures is also important in nests where there is no Shiny Cowbird egg laying.Costos de la Perforación de Huevos y el Parasitismo por Molothrus bonariensis en Nidos de Turdus amaurochalinus

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Breeding biology of common kingfisher (Alcedo atthis, Linnaeus 1758)

Journal of the Asiatic Society of Bangladesh Science ◽

10.3329/jasbs.v47i1.54184 ◽

2021 ◽

Vol 47 (1) ◽

pp. 23-34

Author(s):

Habibon Naher ◽

Noor Jahan Sarker ◽

Shawkat Imam Khan

Keyword(s):

Natural Disaster ◽

Breeding Season ◽

Body Length ◽

Breeding Success ◽

Hatching Success ◽

Total Body Length ◽

Breeding Biology ◽

The Common ◽

Total Body

The breeding biology of the common kingfisher (Alcedo atthis) was studied from 2008 to 2011 in Dhaka North City Corporation and Savar Upazilla. The breeding season was April to September. It laid 3 to 7 glossy white, almost round eggs with a size of 2.5±0.3 cm length, 2.2±0.3 cm breadth, and 5.3±0.7g weight. It incubated for 16 to 21 days. During hatching, the hatchlings’ weight ranged from 8.5 to 10.5 g and total body length from 43.2 to 58.6 mm whereas, it was 30.1 to 32.7 g and 151 to 155.5 mm, respectively, during fledging. Hatching success was 83.3%. Stolen by people (13.9%) and infertility (2.8%) were the causes of egg loss. The young birds fledged out after 21 to 27 days of hatching. A total of 56.7% of nestlings were unable to fly due to stolen (43.3%), deaths due to unknown reasons (6.7%) and deaths due to natural disaster (6.7%). The breeding success was 36.1% in relation to eggs laid and 43.3% in relation to eggs hatched. J. Asiat. Soc. Bangladesh, Sci. 47(1): 23-34, June 2021

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Aspects of Hatching Success and Chick Survival in Gull-Billed Terns in Coastal Virginia

Waterbirds ◽

10.2307/1521993 ◽

1999 ◽

Vol 22 (1) ◽

pp. 54 ◽

Cited By ~ 8

Author(s):

T. Brian Eyler ◽

R. Michael Erwin ◽

Daniel B. Stotts ◽

Jeff S. Hatfield

Keyword(s):

Hatching Success ◽

Chick Survival

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Drone assessment of habitat selection and breeding success of Gull-billed Tern Gelochelidon nilotica nesting on low-accessibility sites: a case study

Rivista Italiana di Ornitologia ◽

10.4081/rio.2020.475 ◽

2021 ◽

Vol 90 (2) ◽

Author(s):

Francesco Scarton ◽

Roberto Valle

Keyword(s):

Habitat Selection ◽

Breeding Success ◽

Hatching Success ◽

Ground Level ◽

Breeding Biology ◽

Nest Attendance ◽

Fish Farms ◽

Breeding Sites ◽

Water Edge

The use of drones in the study of waterbird breeding biology has received considerable attention in the last years, but very few studies were made along the Mediterranean. We studied habitat selection and breeding success of the Gull-billed Tern Gelochelidon nilotica in two colonies inside fish farms along the Italian Adriatic coastline, using a small, commercial drone. Both colonies were located on small islets surrounded by very shallow water and clayey bottoms, thus being difficult to access. Compared with availability, the Gull-billed Terns selected quadrats higher above the water level, with a higher vegetation cover, which lay farther from the water edge, contain less water, and which are more frequently located in the center of the islands. 147 of 178 clutches (mean clutch size ± SD: 2.61 ± 0.58) hatched 383 chicks (82.5%; 2.15 ± 1.09 chicks per nest), with large differences between the two colonies. Hatching success was 95.0% and 69.1%; the most common cause of egg loss was flooding (97.0%). Nest attendance could easily be ascertained by 30-m above ground level drone-derived imagery. The use of a drone allowed the study of some aspects of the breeding biology of the Gull Billed Tern in two breeding sites where the traditional field approach, i.e. researchers reaching the sites by boat, would have been very difficult, causing unavoidable and prolonged disturbance to the nesting adults.

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A Comparative Study of Shiny Cowbird Parasitism of Two Large Hosts, the Chalk-Browed Mockingbird and the Rufous-Bellied Thrush

The Condor ◽

10.1093/condor/105.4.728 ◽

2003 ◽

Vol 105 (4) ◽

pp. 728-736 ◽

Cited By ~ 4

Author(s):

Paula Sackmann ◽

Juan Carlos Reboreda

Keyword(s):

Hatching Success ◽

Nest Survival ◽

Host Defenses ◽

Chick Survival ◽

Egg Survival ◽

Brood Parasites ◽

Molothrus Bonariensis ◽

Cowbird Parasitism ◽

Egg Destruction ◽

Host Parasite

AbstractIt is usually accepted that generalist brood parasites should avoid using hosts larger than themselves because host chicks may outcompete parasite chicks for food. We studied the interactions between the Shiny Cowbird (Molothrus bonariensis) and two common hosts larger than the parasite, the Chalk-browed Mockingbird (Mimus saturninus) and the Rufous-bellied Thrush (Turdus rufiventris). For each host we determined (1) frequency and intensity of parasitism during the breeding season, (2) nesting success, egg survival, hatching success, and chick survival in unparasitized and parasitized nests, and (3) antiparasitic defenses. We also determined Shiny Cowbird egg survival, hatching success, and chick survival in both hosts. Parasitism reached 50% in mockingbirds and 66% in thrushes. In both species the main cost of parasitism was egg destruction through punctures. Hatching success, survival of host chicks, and nest survival did not differ between unparasitized and parasitized nests. Both hosts rejected parasitic white-morph eggs but accepted spotted-morph ones, even though they were significantly smaller than host eggs. The proportion of cowbirds fledged per egg laid in successful mockingbird and thrush nests was 0.4 and 0.6, respectively. Considering nest survival, reproductive success of Shiny Cowbirds was 0.15 in mockingbird nests and 0.17 in thrush nests. These values are similar to or higher than cowbird success with smaller hosts. Our results indicate that host quality is not only determined by host-parasite differences in body size, and that other factors, such as host defenses and nest survivorship, should be considered.Un Estudio Comparado del Parasitismo de Molothrus bonariensis en dos Hospedadores de Gran Tamaño, Mimus saturninus y Turdus rufiventrisResumen. Es aceptado generalmente que los parásitos de cría generalistas deberían evitar utilizar hospedadores de mayor tamaño corporal porque los pichones del hospedador podrían desplazar a sus pichones en la competencia por alimento. Se estudiaron las interacciones entre Molothrus bonariensis y dos hospedadores frecuentes de mayor tamaño que el parásito, Mimus saturninus y Turdus rufiventris. Para cada hospedador se determinó (1) frecuencia e intensidad de parasitismo durante la temporada reproductiva, (2) éxito de nidificación, supervivencia de huevos, éxito de eclosión y supervivencia de pichones en nidos no parasitados y parasitados, y (3) defensas antiparasitarias. También se determinó el éxito reproductivo del parásito en ambos hospedadores. El porcentaje de nidos parasitados fue 50% en Mimus saturninus y 66% en Turdus rufiventris. En ambas especies, el principal costo del parasitismo fue la destrucción de huevos por picaduras. El éxito de eclosión, la supervivencia de pichones y el éxito de nidificación fueron semejantes entre nidos no parasitados y parasitados. Ambos hospedadores rechazaron los huevos parásitos del morfo blanco pero aceptaron los del morfo manchado, si bien éstos fueron de menor tamaño que los del hospedador. La proporción de volantones de Molothrus bonariensis por huevo puesto en nidos exitosos de Mimus saturninus y Turdus rufiventris fue 0.4 y 0.6, respectivamente. Considerando la supervivencia de los nidos, el éxito reproductivo fue 0.15 en Mimus saturninus y 0.17 en Turdus rufiventris. Estos valores son similares o mayores que los reportados para hospedadores de menor tamaño que el parásito. Nuestros resultados indican que la calidad del hospedador no está sólo determinada por las diferencias en tamaño corporal entre el hospedador y el parásito y que otros factores, como defensas del hospedador y supervivencia de los nidos, deberían ser considerados.

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Reproductive Success of Shiny Cowbird (Molothrus Bonariensis) Parasitizing the Larger Brown-and-Yellow Marshbird (Pseudoleistes Virescens) in Argentina

The Auk ◽

10.1093/auk/120.4.1128 ◽

2003 ◽

Vol 120 (4) ◽

pp. 1128-1139

Author(s):

Myriam E. Mermoz ◽

Juan C. Reboreda

Keyword(s):

Growth Rate ◽

Reproductive Success ◽

Clutch Size ◽

Life History Traits ◽

Hatching Success ◽

Chick Survival ◽

Molothrus Bonariensis ◽

Large Clutch ◽

Survival And Growth ◽

Host Life

Abstract Shiny Cowbirds (Molothrus bonariensis) often parasitize larger hosts. It has been proposed that larger hosts are preferred by that parasite because they provide higher reproductive success, but available data are quite variable. We studied the reproductive success of Shiny Cowbirds in nests of Brown-and-yellow Marshbirds (Pseudoleistes virescens), a larger and often multiply parasitized host. To estimate the extent of interspecific competition, we compared the hatching success of parasite eggs in nests with and without reduction of the clutch size of the host as a result of egg punctures inflicted by the parasite, and the survival and growth of parasite chicks reared with and without host chicks. To estimate the extent of intraspecific competition, we compared Shiny Cowbird egg losses, hatching success, and chick survival in singly versus multiply parasitized nests. Reproductive success of Shiny Cowbirds was 8% with depredation causing 80% of losses. Clutch reduction due to egg punctures were higher in multiply than in singly parasitized nests, but it did not improve hatching success of parasite eggs. Neither survival nor growth of parasite chicks was affected by the presence of host chicks. Shiny Cowbird hatching success and chick survival did not differ between singly and multiply parasitized nests. Parasite chicks were smaller than same-age Brown-and-yellow Marshbird chicks. However, because parasite chicks hatched one or two days before host chicks and had a higher growth rate, they were the larger chicks in the nest. Overall Shiny Cowbird reproductive success in Brown-and-yellow Marshbird nests was apparently higher than that reported in other smaller or similar-sized hosts. We think that host life-history traits like large clutch size, a longer incubation period, and slower growth rate of chicks are responsible for the high reproductive success of Shiny Cowbirds with Brown-and-yellow Marshbirds.

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