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A Common Grackle (Quiscalus quiscula) was observed consuming eggs from an exclosed (protected) Great Lakes Piping Plover (Charadrius melodus) nest in the lower bay of Green Bay, Lake Michigan in Wisconsin, USA during June 2023. The observation, captured by a trail camera, is the first photographic documentation of grackle predation in any of the three Piping Plover breeding populations. This behavior adds Common Grackle to the suite of egg predators and has critical implications for this shorebird species, particularly in the Great Lakes region where Piping Plover is listed as federally endangered and Common Grackles are relatively abundant. Given that current nest protection efforts rely on exclosures with openings that enable access by grackles, we recommend (1) identification of Piping Plover nesting locations across the Great Lakes region that are frequently used by Common Grackle, and (2) subsequent alteration of exclosure use (e.g., omission to prevent cueing by grackles or possible structural modification to prevent access) and/or habitat or predator management at locations where grackles are particularly problematic. In addition, increased deployment of trail cameras at Great Lakes sites will help elucidate the extent to which Common Grackle predation of Piping Plover nests is a population-wide threat. [ABSTRACT FROM AUTHOR]

Abstract Background Climate change due to anthropogenic global warming is the most important factor that will affect future range distribution of species and will shape future biogeographic patterns. While much effort has been expended in understanding how climate change will affect rare and declining species we have less of an understanding of the likely consequences for some abundant species. The Common Grackle (Quiscalus quiscula; Linnaeus 1758), though declining in portions of its range, is a widespread blackbird (Icteridae) species in North America east of the Rocky Mountains. This study examined how climate change might affect the future range distribution of Common Grackles. Methods We used the R package Wallace and six general climate models (ACCESS1-0, BCC-CSM1-1, CESM1-CAM5-1-FV2, CNRM-CM5, MIROC-ESM, and MPI-ESM-LR) available for the future (2070) to identify climatically suitable areas, with an ecological niche modelling approach that includes the use of environmental conditions. Results Future projections suggested a significant expansion from the current range into northern parts of North America and Alaska, even under more optimistic climate change scenarios. Additionally, there is evidence of possible future colonization of islands in the Caribbean as well as coastal regions in eastern Central America. The most important bioclimatic variables for model predictions were Annual Mean Temperature, Temperature Seasonality, Mean Temperature of Wettest Quarter and Annual Precipitation. Conclusions The results suggest that the Common Grackle could continue to expand its range in North America over the next 50 years. This research is important in helping us understand how climate change will affect future range patterns of widespread, common bird species.

Wing-assisted incline running (WAIR) has been observed in bird taxa from multiple clades. Its wide phylogenetic distribution in modern birds suggests that it is an ancestral trait for class Aves. WAIR as a behaviour is speculated to predate the evolution of full-powered flight, and to have formed a behavioural and physiological stepping stone between terrestrial and aerial life. Here I report an observation of apparent WAIR in a Common Grackle (Quiscalus quiscula) photographed incidentally on a trail camera deployed in an urban backyard in Guelph, Ontario, Canada. To my knowledge this is the first documented observation of apparent WAIR for the family Icteridae. Furthermore, it highlights the value of non-systematic use of trail cameras for making unique natural history observations. [ABSTRACT FROM AUTHOR]

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Climate change due to anthropogenic global warming is the most important factor that will affect future range distribution of species and will shape future biogeographic patterns. While much effort has been expended in understanding how climate change will affect rare and declining species we have less of an understanding of the likely consequences for some abundant species. The Common Grackle (Quiscalus quiscula; Linnaeus 1758), though declining in portions of its range, is a widespread blackbird (Icteridae) species in North America east of the Rocky Mountains. This study examined how climate change might affect the future range distribution of Common Grackles. Methods: We used the R package Wallace and six general climate models (ACCESS1-0, BCC-CSM1-1, CESM1-CAM5-1-FV2, CNRM-CM5, MIROC-ESM, and MPI-ESM-LR) available for the future (2070) to identify climatically suitable areas, with an ecological niche modelling approach that includes the use of environmental conditions. Results: Future projections suggested a significant expansion from the current range into northern parts of North America and Alaska, even under more optimistic climate change scenarios. Additionally, there is evidence of possible future colonization of islands in the Caribbean as well as coastal regions in eastern Central America. The most important bioclimatic variables for model predictions were Annual Mean Temperature, Temperature Seasonality, Mean Temperature of Wettest Quarter and Annual Precipitation. Conclusions: The results suggest that the Common Grackle could continue to expand its range in North America over the next 50 years. This research is important in helping us understand how climate change will affect future range patterns of widespread, common bird species. [ABSTRACT FROM AUTHOR]

Despite a generalist life history and a widespread distribution, the Common Grackle (Quiscalus quiscula) has declined by more than 58% since 1970. In Illinois, where this study was conducted, the current rate of decline is 7.03% annually. We hypothesized that low reproductive success in intensely agricultural areas is driving population decline. To test this, we quantified the nesting success and post-fledging survival of Common Grackles in central Illinois. Over a 2-year period, we monitored 188 nests and tracked the survival of 53 fledglings. Our estimate for nesting success of 0.622 (95% CI: 0.549-0.695) was much higher than the literature average of 0.267. Similarly, although post-fledging survival had not been estimated previously for Common Grackles, our estimate of 0.617 (95% CI: 0.471-0.764) was relatively high compared to that of other songbirds (range: 0.23-0.87). The most important factor influencing these estimates was ordinal date, which had a negative relationship with both nesting success and post-fledging survival. These results suggest that reproductive success is not the primary driver of population decline in Illinois. To expand upon the field portion of our study, we constructed a demographic model and used it to conduct a global sensitivity analysis. In our model, adult survival was the most influential demographic parameter in the context of population change. This study serves as an initial step in understanding the mechanism(s) of decline in the Common Grackle. We recommend additional research on the survival of Common Grackles, particularly in relation to persecution on the wintering grounds and exposure to agricultural chemicals.

The article offers information on Common grackle bird as of first record from Sonora, Mexico. topics discussed include field identification was based on the grackle's being slightly larger than the Bronzed Cowbirds, having a longer tail and heavier bill; species is a late fall migrant; and shows a pattern of vagrancy in the southwestern United States just north of Sonora, Mexico.

A total of 31 Common Grackles were captured while banding during a late spring snowstorm at a feeding station in Meade, Meade County, Kansas, on 14 April 2014. Of these 31, one bird was a recapture from 2012, one was recaptured later in the summer (2014), one was recovered in Colorado, and one was encountered from Colorado. An additional encounter from eastern Colorado during winter in Meade, and a recovery of a Meade bird from southeastern Oklahoma during winter, suggest birds from the front range of Colorado winter from Meade, Kansas, through southeastern Oklahoma. [ABSTRACT FROM AUTHOR]

Environmental factors such as heat and solar radiation directly affect the open-cup nest environment and can impact nestling body temperature., The aim of our research was to understand how open-cup passerine nestlings use behavioural thermoregulation to mitigate solar heat gain and to measure the metabolic cost of begging and non-begging activity under three light treatments: room light (<2 Wm−2), simulated shade (500 Wm−2) and simulated sun (1000 Wm−2). Our study coupled behavioural (field) and physiological (laboratory) experiments to explore the adaptive behavioural response of passerine nestlings to nest cup nanoclimates (sun and shade), using the common grackle ( Quiscalus quiscula) as a model species., Non-begging behaviour was evaluated in the field by randomly assigning nestlings to a homogeneous (all sun) or heterogeneous (sun and shade) nest environment; measuring body temperature ( Tb); and identifying behaviours from videotaped footage. The Tb of nestlings without access to shade was significantly higher, and nestlings spent more time moving and panting, suggesting an increased metabolic expenditure. To test this, we duplicated the insolation nanoclimate under laboratory conditions using a 1·0 KW Sciencetech Illumination System and measured the energetic cost of begging and non-begging activity using open-system respirometry on non-irradiated and irradiated nestlings. Our results suggest that, in grackle nestlings, the relationship between activity (begging and non-begging) and energy expenditure is context-dependent., Our results identified: (i) a reduction in energy expenditure associated with accessing the shade; (ii) expenditure on non-begging activity equalled or exceeded expenditure on begging activity; and (iii) a potential behavioural constraint on begging imposed by exposure to a homogeneous sun environment (sun without access to shade). The combination of context-dependent costs and constraints suggests the potential for strategic costs associated with the heterogeneous nest environment . [ABSTRACT FROM AUTHOR]

The article aims to study the helminths of common grackles that feed on fish and compare against the helminths found in belted kingfishers located in the same Ohio hatchery. It states that 35 adult common grackles were collected and parts including the brain, trachea and digestive tract were examined and where six helminth species including digenetic trematode, cestode, and nematode species were found. A table showing the prevalence, mean intensity and abundance of helminths is presented.

The article discusses the results of the 2012 Summer Bird Count in Connecticut. The annual Summer Bird Count aims to determine the distribution and status of breeding birds in the state. For 2012, 184 count day species were recorded, with 115598 individual birds counted. Some of the most abundant species recorded include the American Robin, Common Grackle and European Starling.

Chandlerella quiscali is a filarial nematode parasite of the common grackle (Quiscalus quiscula), a widespread bird species found throughout most of North America. Worms collected from wild-caught birds were morphologically identified as C. quiscali and tested for the presence of Wolbachia, an alphaproteobacterial endosymbiont required for reproduction and maturation by many filarial species. Although various methods, including polymerase chain reaction, in situ hybridization, and immunohistology, were used, we were unable to detect evidence of colonization with Wolbachia. Due to the widespread distribution of the grackle host, localization within the host, and high prevalence, C. quiscali may be among the most easily obtainable of Wolbachia-free filarial species. Further studies of C. quiscali and other Wolbachia-free filarial species may help to clarify the reason(s) that some filarial species require Wolbachia but others do not. [ABSTRACT FROM AUTHOR]

Birds attracted to nest around coal ash settling basins may expose their young to contaminants by provisioning them with contaminated food. Diet and tissues of Common Grackle (Quiscalus quiscala) nestlings were analyzed for trace elements to determine if nestlings were accumulating elements via dietary exposure and if feather growth limits elemental accumulation in other tissues. Arsenic, cadmium, and selenium concentrations in ash basin diets were 5× higher than reference diets. Arsenic, cadmium, and selenium concentrations were elevated in feather, liver, and carcass, but only liver Se concentrations approached levels of concern. Approximately 15% of the total body burden of Se, As, and Cd was sequestered in feathers of older (>5 days) nestlings, whereas only 1% of the total body burden of Sr was sequestered in feathers. Feather concentrations of only three elements (As, Se, and Sr) were correlated with liver concentrations, indicating their value as non-lethal indicators of exposure. [Copyright &y& Elsevier]

Copyright of Journal of Field Ornithology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two of 36 forest restoration sites in the Mississippi Alluvial Valley surveyed from 2000-2002 harbored Quiscalus quiscula (Common Grackle). Occupied sites were in less-forested landscapes and had sparser understory vegetation due to flooding. Probability of daily nest survival (0.9077) of 169 Common Grackle nests was influenced by nest-placement, temporal, and landscape effects. Age of nest markedly affected nest survival, which increased from <0.89 during egg laying (age < 6 days) to >0.92 when nestlings were present (age > 18 days). Extrapolating daily nest survival to a 3 l-day nest period resulted in 5% nest success, far less then previously estimated for this species in more northern latitudes and likely less than required to sustain populations on these sites. [ABSTRACT FROM AUTHOR]

In this article, the author discusses seasonal sex allocation among common grackles. The author examines the study by Maddox and Weatherhead on the sex ratios of grackles in which they did not exhibit seasonal trends. The author compares the study by Maddox to his study on the sex ratio which manifests female control through nonrandom meiosis during the season. Moreover, he notes that Maddox and Weatherhead broaden the knowledge in the sex ratio adjustment and its absence in common grackles.

This article discusses a study which examined the relation between intraclutch egg variation and egg rejection behavior in Common Grackle (Quiscalus quiscula), common host of the Brown-headed Cowbird (Molothrus ater). Researchers discovered that Common Grackles with greater variation in intraclutch egg appearance were more likely to accept cowbird eggs when added prior to clutch completion.

The article discusses a study on the consistency of responses of Common Grackles to repeated avian brood parasitism involving Brown-headed Cowbird eggs. A comparison of the responses of various rejecter species of birds such as Blue Jay and Gray Catbird to investigational multiple parasitism is given. The intraclutch variation in appearance of Common Grackle eggs and its possible influence on the rejection behavior of the bird are assessed.

Despite the general importance of replication in science, relatively few behavioral ecology studies are repeated. Here we repeat the seminal 1977 research of H. F. Howe, who found that the proportion of male nestlings at hatching in nests of Common Grackles (Quiscalus quiscula) increased as the breeding season progressed. Howe interpreted this pattern as an adaptive response to changing food conditions that favored greater production of daughters (the sex less expensive to rear) when food was scarce and sons when food was more abundant. Using DNA-based sexing and larger samples, we found no evidence of nonrandom seasonal sex allocation and no evidence that sons were more vulnerable to starvation than daughters. These patterns also prevailed among renesting efforts late in the season, when starvation was extreme. Although there is no way to exclude the possibility that grackles employed different sex allocation tactics in the two studies, similarities in weather, habitat, nesting phenology, and starvation rates make it seem unlikely that ecological differences between our study and Howe's explain the disparate results, whereas failure of assumptions that Howe was unable to test seems more plausible. [ABSTRACT FROM AUTHOR]

Abstract: Solar radiation is a major source of heat for open-cup passerine nestlings, and a key variable influencing parental nest site selection. Although temperature, like food, is critical for nestling growth and survival, the use of thermal and insolation gradients when describing passerine nestling orientation and movement within the open-cup nest has not been explored. Our study used the Common Grackle (Quiscalus quiscula) as a model system to directly test the hypothesis that passerine nestlings mitigate thermal extremes behaviourally. Pairs of nestlings were tested in shaded (homogeneous) and exposed (heterogeneous) nests, movements within nests were tracked and nest temperatures recorded. Our results show that nestlings are able to detect and respond to nanoclimate heterogeneity, and can mitigate short-term radiant heat loads through shade-seeking. [Copyright &y& Elsevier]

Bird–aircraft collisions are costly and potentially deadly to people and wildlife. From 1990 through 2004, 57 702 bird collisions with aircraft were reported within the USA to the US Federal Aviation Administration. Approximately 82% of the strikes occur below 305 m height above ground level; therefore bird deterrents on airfields that reduce the quality of the birds' habitat are critical to safe airport operation. One management approach is to reduce perching sites within the airport premises. We tested two anti-perching devices (Birdwire™ and BirdBlox™) in an aviary setting. As an ancillary test, we determined which wire in a standard three-strand security array was preferred by blackbirds and starlings. Red-winged blackbirds (Agelaius phoeniceus), brown-headed cowbirds (Molothrus ater), and European starlings (Sturnus vulgaris) were deterred from sitting on a perch when anti-perching wire was installed 5 cm above the perch. These same species preferred the top wire of the three-wire security array. Red-winged blackbirds, common grackles (Quiscalus quiscula), brown-headed cowbirds, European starlings, and rock pigeons (Columba livia) were deterred from perches protected by BirdBlox™. Because our tests were conducted in a captive situation, we recommend field testing the products to determine if bird use of airport structures may be reduced in an operational setting. [ABSTRACT FROM AUTHOR]

We determined whether nests that did not receive eggs was attributable to cryptic nest predation (i.e. predation of eggs laid between nest checks) or nest abandonment in Common Grackles (Quiscalus quiscula). Nest predation was extremely low (∼2%), whereas more than 44% of 427 nests found during nest building never received an egg; this indicates that nest abandonment accounted for most nests without eggs. Nest construction was completed for 32% of nests that were abandoned. Few nests known to have received eggs were abandoned. As the breeding season progressed, both nest abandonment and time from nest completion to first egg decreased. It has been proposed that the delay in egg laying early in the season allows females to optimize timing of egg laying. Nest abandonment may also serve this purpose, but seems an unnecessarily expensive mechanism. Alternatively, nest abandonment could be involved with mate switching. Understanding why nests are abandoned requires data on the associated ecological circumstances, in addition to accurate identification of instances of abandonment. The latter requires distinguishing abandonment from cryptic predation. Rates of nest abandonment can be estimated for populations by using rates of known nest predation during egg laying. For individual nests, however, distinguishing abandonment from cryptic predation requires detailed observation (e.g. video cameras), except in circumstances such as ours, where predation is extremely low. [ABSTRACT FROM AUTHOR]

Chemical repellents sometimes can provide a nonlethal alternative for reducing wildlife impacts to agricultural production. In late summer and autumn 2002, we evaluated Bird Shield™(active ingredient: methyl anthranilate, Bird Shield Repellent Corporation, Spokane, Wash.) as a blackbird (Icteridae) repellent in Missouri rice fields and North Dakota sunflower fields. We selected 5 pairs of ripening rice fields in southeastern Missouri and randomly allocated treatments (treated and control) within pairs. The repellent was aerially applied by fixed-winged aircraft at the recommended label rate and volume (1.17 L Bird Shield/ha and 46.7 L/ha, respectively); 1 field received 2X the label rate. We observed no difference in average bird activity (birds/minute) between treated and control fields over the 3-day post-treatment period (P = 0.503). We used reversed-phase liquid chromatography to quantify methyl anthranilate residues in treated fields. The maximum concentration of methyl anthranilate in rice samples was 4.71 μg/g. This concentration was below reported threshold values that irritate birds. In North Dakota we selected 6 pairs of sunflower fields used by foraging blackbirds. We randomly selected 1 field from each pair for 2 aerial applications of Bird Shield at the label-recommended rate -1 week apart. The remaining 6 fields served as controls. Daily bird counts, starting the first day of application and continuing for 5-7 days after the second application, showed similar numbers of blackbirds within treated and control fields (P = 0.964). We observed no difference in sunflower damage within treated and control fields (P = 0.172) prior and subsequent to the treatment. Bird Shield was not effective for repelling blackbirds from ripening rice and sunflower fields. [ABSTRACT FROM AUTHOR]

The article discusses the bioenergetic model assessment on economic impact on sunflower production on blackbirds (Icteridae) population consisting of three species including red-winged blackbirds (Agelaius phoeniceus), common grackles (Quiscalus quiscula), and yellow-headed blackbird (Xanthocephalus xanthocephalus). The species damage affects sunflower harvest in the northern Great Plains of North America based on the analysis did.

The article offers the authors' insight on the comment of Henry F. Howe about their study regarding seasonal sex allocation among common grackles. The authors say that they did not challenge the sex-ratio theory or question contingent behavior as an important ecological phenomenon in their study. Furthermore, they suggest explanations to understand the difference between the results of the two studies such as wrong interpretation in Howe's study due to failed assumptions.

Microfilariae (MF) are the immature stages of filarial nematode parasites and inhabit the blood and dermis of all classes of vertebrates, except fish. Concurrent ingestion of MF and arboviruses by mosquitoes can enhance mosquito transmission of virus compared to when virus is ingested alone. Shortly after being ingested, MF penetrate the mosquito's midgut and may introduce virus into the mosquito's hemocoel, creating a disseminated viral infection much sooner than normal. This phenomenon is known as microfilarial enhancement. Both American Robins and Common Grackles harbor MF-that is, Eufilaria sp. and Chandlerella quiscali von Linstow (Spirurida: Onchocercidae), respectively. We compared infection and dissemination rates in Culex pipiens L. mosquitoes that fed on birds with and without MF infections that had been infected with West Nile virus (WNV). At moderate viremias, about 107 plaque-forming units (pfu)/ml of blood, there were no differences in infection or dissemination rates among mosquitoes that ingested viremic blood from a bird with or without microfilaremia. At high viremias, >108.5 pfu/ml, mosquitoes feeding on a microfilaremic Grackle with concurrent viremia had significantly higher infection and dissemination rates than mosquitoes fed on viremic Grackles without microfilaremia. Microfilarial enhancement depends on the specific virus, MF, and mosquito species examined. How virus is introduced into the hemocoel by MF differs between the avian/WNV systems described here (i.e., leakage) and various arboviruses with MF of the human filarid, Brugia malayi (Brug) (Spirurida: Onchocercidae) (i.e., cotransport). Additional studies are needed to determine if other avian species and their MF are involved in the microfilarial enhancement of WNV in nature., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America.All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The article reports that Common Grackles were seen at Exeter Marsh in Lebanon, Connecticut. It states that the birds cannot be seen during daytime and mornings can be chaotic for birds if it rains while they try to reach cornfields. It mentions that they swirl around to roost along with Red-Winged Blackbirds.