Tuesday, June 22, 2021
Friday, May 7, 2021
Godwits & Wllets - Ph. by Ingrid Taylar
World Shorebird Day is September 6th this year. It is important to participate in this global event. Learn more at https://www.worldshorebirdsday.org/global-shorebird-counts
"The Global Shorebird Counts, held every year around World Shorebirds Day (6 September), is one of the key events of World Shorebirds Day. This program demonstrates the importance of fieldwork, supports observers in improving counting skills, contributes to the increase of the number of birdwatchers and scientists monitoring shorebirds worldwide and pledges new citizen scientists to the world’s largest bird database program."
Recent articles on the global declines of shorebirds are linked here:
Lastly, here is shorebird news from BirdLife International:
Saturday, January 30, 2021
NEW GRASSLAND BIRD RESEARCH: Linking Migratory Songbird Declines With Increasing Precipitation and Brood Parasitism Vulnerability
Not Singing in the Rain: Linking Migratory Songbird Declines With Increasing Precipitation and Brood Parasitism Vulnerability
- 1International Bird Conservation Partnership, Monterey, CA, United States
- 2Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden
- 3Crane Trust, Wood River, NE, United States
- 4Cooperative Wildlife Research Laboratory, Southern Illinois University, Carbondale, IL, United States
- 5U.S. Fish and Wildlife Service, Pierre, SD, United States
- 6Center for Great Plains Studies, University of Nebraska–Lincoln, Lincoln, NE, United States
Few empirical studies have quantified relationships between changing weather and migratory songbirds, but such studies are vital in a time of rapid climate change. Climate change has critical consequences for avian breeding ecology, geographic ranges, and migration phenology. Changing precipitation and temperature patterns affect habitat, food resources, and other aspects of birds’ life history strategies. Such changes may disproportionately affect species confined to rare or declining ecosystems, such as temperate grasslands, which are among the most altered and endangered ecosystems globally. We examined the influence of changing weather on the dickcissel (Spiza americana), a migratory songbird of conservation concern that is an obligate grassland specialist. Our study area in the North American Great Plains features high historic weather variability, where climate change is now driving higher precipitation and temperatures as well as higher frequencies of extreme weather events including flooding and droughts. Dickcissels share their breeding grounds with brown-headed cowbirds (Molothrus ater), brood parasites that lay their eggs in the nests of other songbirds, reducing dickcissel productivity. We used 9 years of capture-recapture data collected over an 18-year period to test the hypothesis that increasing precipitation on dickcissels’ riparian breeding grounds is associated with abundance declines and increasing vulnerability to cowbird parasitism. Dickcissels declined with increasing June precipitation, whereas cowbirds, by contrast, increased. Dickcissel productivity appeared to be extremely low, with a 3:1 ratio of breeding male to female dickcissels likely undermining reproductive success. Our findings suggest that increasing precipitation predicted by climate change models in this region may drive future declines of dickcissels and other songbirds. Drivers of these declines may include habitat and food resource loss related to flooding and higher frequency precipitation events as well as increased parasitism pressure by cowbirds. Positive correlations of June-July precipitation, temperature, and time since grazing with dickcissel productivity did not mitigate dickcissels’ declining trend in this ecosystem. These findings highlight the importance of empirical research on the effects of increasing precipitation and brood parasitism vulnerability on migratory songbird conservation to inform adaptive management under climate change.
Friday, January 15, 2021
Habitat ecology of Nearctic–Neotropical migratory landbirds on the nonbreeding grounds
The Condor, Volume 122, Issue 4, 2 November 2020
The abstract reads (in part):
" Of the approximately 716 bird species that breed in North America, 386 (54%) are considered Nearctic–Neotropical migrants by the U.S. Fish and Wildlife Service. In the past 50 yr, scores of these migratory species, including some once considered common, have declined dramatically. Nearctic–Neotropical migrants normally spend 6–8 months in tropical habitats, making the identification, availability, and management of Neotropical habitats critical issues for their conservation. Yet, for most species, complete and nuanced information about their use of tropical habitats and the relative effects of breeding vs. wintering conditions on survival, productivity, and population trends is not available, though many studies point to Neotropical overwintering habitats as being a strong driver of population change. Particularly important for long-distance Nearctic–Neotropical migrants is an understanding of how “carry-over effects” arise and influence population trends when conditions on wintering grounds and tropical stopover areas affect subsequent reproductive performance on breeding grounds."
Saturday, December 26, 2020
Although it may surprise some people, and in fact we should have seen its end long before now, the illegal international trade in wild birds continues. Learn more about it, and what you can do to help it cease:
Hyacinth Macaw, by Donna Sullivan Thomson
Wednesday, November 18, 2020
Each year additional studies on the effect of climate change on wild birds are published.
New publications include the following:
Risk to North American birds from climate change‐related threats https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/csp2.243
North American birds require mitigation and adaptation to reduce vulnerability to climate change https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/csp2.242
Shifts in migration phenology under climate change: temperature vs. abundance effects in birds https://link.springer.com/article/10.1007/s10584-020-02668-8
Shared morphological consequences of global warming in North American migratory birds https://onlinelibrary.wiley.com/doi/abs/10.1111/ele.13434
Thursday, August 27, 2020
A growing body of research demonstrates that aerial insectivores as a group are undergoing population changes, and in some species (nightjars, some swallows) are experiencing population declines.
The following papers describe some of what has been learned:
Evidence for multiple drivers of aerial insectivore declines in North America
"Aerial insectivores (birds that forage on aerial insects) have experienced significant population declines in North America. Numerous hypotheses have been proposed for these declines, but current evidence suggests multiple factors could be operating in combination during their annual migratory cycles between breeding and nonbreeding areas. Potential drivers include decreased prey abundance, direct or indirect impacts of environmental contaminants, habitat loss, phenological changes due to warming climate, and conditions on migratory stopover or wintering grounds."
Nebel, S., A. Mills, J. D. McCracken, and P. D. Taylor. 2010. Declines of aerial insectivores in North America follow a geographic gradient. Avian Conservation and Ecology - Écologie et conservation des oiseaux 5(2): 1. [online] URL: http://www.ace-eco.org/vol5/iss2/art1/