1. Imagine walking coast-to-coast across the United States and back—6,000 miles—over the span of a few weeks, using nothing but your own body power. Now imagine you are the size of a lime. That’s akin to what some Blackpoll Warblers face as they start off from Colombia each spring on the way north to breeding grounds in the boreal forest. Despite the grueling trip, blackpolls are among the most abundant warblers within their vast breeding range, which stretches from New England to the Maritime Provinces of Canada and across the continent to Alaska. But this once-robust population is crumbling, suffering a 90% loss in the last 50 years. Today there are tens of millions of blackpolls embarking on spring migration, whereas in the mid-20th century there may have been hundreds of millions. (via Living Bird Magazine)
2. Piping plover breeding groups in the Northern Great Plains are notably connected through movements between habitats and show lower reproductive rates than previously thought, according to a new U.S. Geological Survey study. These new findings point to a need for further studies and suggest the species may show a higher extinction risk than currently presumed. Study findings show managing for successful first nests for Northern Great Plains piping plovers is key to improving reproductive output. (via Science Daily)
3. The Common Myna continues to be the most commonly spotted bird in India (except for the western region), with the Red-vented Bulbul upending the House Crow to move to second position in the list of common birds sighted in India. The presence of the Rose-ringed Parakeet has also increased, with the species being reported across the country now, instead of being reported from north and western India. These and many other interesting trends were gleaned from the India data of the Great Backyard Bird Count (GBBC), which took place in February. In India, Bird Count India has been coordinating the event since 2013. (via Mint Lounge)
4. Power of eBird: For the past 50 years, the U.S. Fish and Wildlife Service has been assembling counts of Bald Eagle nests from the states and by aircraft surveys to track the triumphant population recovery of America’s national symbol. But in its new Bald Eagle population report—tabulated with the help of results using eBird data from the Cornell Lab of Ornithology—the USFWS found many more eagles than previously thought to exist in the Lower 48 states. A lot more. The latest USFWS Bald Eagle Population Update report estimates 316,708 eagles across the contiguous United States, which is more than quadruple the eagle population reported in the 2009 report. The rising number of Bald Eagles undoubtedly reflects the continuing conservation success story that stretches back to the banning of DDT in 1972. (via Living Bird Magazine)
5. But still, there is this: In a sample of eagles from across the US, rat poison was found in about 80 percent of the birds. This widespread exposure to toxic chemicals could impair their health or even lead to death. Between 2014 and 2018, Ruder and his team determined the cause of death for 303 golden eagles (Aquila chrysaetos) and bald eagles (Haliaeetus leucocephalus), which were sent to them from around the US. Some deaths couldn’t be explained, but the team determined that 4 percent of the eagles died directly as a result of rat poison. They tested 133 of the birds for anticoagulant rodenticide, the most common rodenticide, which can also target opossums and beavers, and found that 82 percent of the birds had it in their body. (via New Scientist)
6. Avian brood parasites lay their eggs in the nests of other bird species, forcing the hosts to do the hard work of raising the unrelated young. A team of scientists wanted to simulate the task of piercing an egg — a tactic that only a minority of host birds use to help grasp and eject the foreign eggs. Their study offers insight into some of the physical challenges the discriminating host birds face. Take cowbirds, for example. Their eggs look nothing like the host birds' eggs, "yet most of their hosts do not reject the parasite eggs," said study co-author Mark Hauber, a professor of evolution, ecology and behavior at the U. of I. and a brood parasitism expert. "One explanation is that the cowbird eggshell is too thick and strong for a small host's beak to pierce." (via Science Daily)
7. Researchers at Lund University in Sweden have discovered that bird blood produces more heat in winter, when it is colder, than in autumn. The secret lies in the energy factories of cells, the mitochondria. Mammals have no mitochondria in their red blood cells, but birds do, and according to the research team from Lund and Glasgow this means that the blood can function as a central heating system when it is cold. Until now, the common perception has been that birds keep warm by shivering with their large pectoral muscles and fluffing up their feathers. Less is known about other heat-regulating processes inside birds. (via Phys Org)
8. Stefania Travaglia is a member of the Committee Against Bird Slaughter (CABS), an anti-poaching activist group dedicated to bird conservation in Europe. It is estimated that between 11 million and 36 million birds are killed or taken illegally in Mediterranean countries every year, many of them while migrating. The group has been active in Brescia, northern Italy, since the early 1980s. Brescia, part of the Lombardy region, is the worst-affected area. CABS believes that between 400,000 and one million birds a year are poached in Brescia. Despite being illegal, the trapping of songbirds has long been a persistent issue in the region. (via The Guardian)
9. Researchers at the University of Konstanz and Max Planck Institute for Animal Behavior in Germany have found that birds are able to change their culture to become more efficient. Populations of great tits were able to switch from one behavior to a better alternative when their group members were slowly replaced with new birds. Published today as open access in the journal Current Biology, this research reveals immigration as a powerful driver of cultural change in animal groups that could help them to adapt to rapidly changing environments. (via Science Daily)
10. Shorebird lovers take note: In a typical year, many Western Hemisphere Shorebird Reserve Network (WHSRN) sites hold festivals to celebrate migration, birds, and wetlands. As migrating birds move from stop to stop, communities along the way come together to welcome the birds back. With their incredible migrations, large flocks, and predictable movements, shorebirds are often one of the main draws at any bird festival. These festivals are one of our greatest tools for building support for conservation and engaging people with nature. Manomet has complied a list of some great festivals coming up this year. Many of the South American festivals that occur on non-breeding grounds have already taken place, but spring migration in North America is just getting started, and so are the festivals. (via Manomet)
Bonus: Most people think of New Jersey as crowded, and it is the most densely populated state—thoroughly urban with high-rises dotting the skyline. But New Jersey is also a key stopover region for millions of migratory warblers, as well as home ground for several warbler species that choose to stay, breed, and raise their young. Some warblers have managed to scratch out survival amid the precious few green spaces tucked in the shadows of cities, such as the open marshes just outside of Atlantic City. Forest birds can be found here, too, such as Ovenbirds in the postage-stamp woodlots that haven’t been sold off as real estate yet. (via Living Bird Magazine)
Bird Photo of the Week
Photo by Hap Ellis, Shorebirds in San Diego.
Bird Videos of the Week
By Cornell Lab of Ornithology, “Birds of the Mississippi River Delta”.
Cornell Live Bird Cam - Barred Owl.
Cornell Live Bird Cam - Cornell Hawks.