1. Across North America, hundreds of bird species waste time and energy raising chicks that aren’t their own. They’re the victims of a “brood parasite” called the cowbird, which adds its own egg to their clutch, tricking another species into raising its offspring. One target, the yellow warbler, has a special call to warn egg-warming females when cowbirds are casing the area. Now, researchers have found the females act on that warning 1 day later—suggesting their long-term memories might be much better than thought. “It’s a very sophisticated and subtle behavioral response,” says Erick Greene, a behavioral ecologist at the University of Montana, Missoula. (via Science)
2. The Power of eBird: In the fall of 2018, Red-breasted Nuthatches were going places. On one morning in Cape May County in New Jersey, birders Michael O’Brien and Doug Gochfeld tallied a total of 1,570 Red-breasted Nuthatches zooming past their count site in just under four hours—the highest number of the species ever recorded on an eBird checklist. The hungry birds were escaping the boreal forest’s subpar crop of fruit, seeds, and cones and spilling south across wide swaths of the U.S. to find food in the woods and at backyard bird feeders. That’s not surprising, as Red-breasted Nuthatches are a classic irruptive species. According to Birds of the World, the Red-breasted Nuthatch is “unique among North American nuthatches… as the only species to undergo regular irruptive movements that appear to be primarily driven by a shortage of winter food on the breeding grounds.” (via Living Bird)
3. In case you were wondering: There’s physics to having your ducklings in a row. By paddling in an orderly line behind their mother, baby ducks can take a ride on the waves in her wake. That boost saves the ducklings energy, researchers report in the Dec. 10 issue of the Journal of Fluid Mechanics. Using computer simulations of waterfowl waves, naval architect Zhiming Yuan of the University of Strathclyde in Glasgow, Scotland, and colleagues calculated that a duckling cruising in just the right spot behind its mother gets an assist. When a duckling swims on its own, it kicks up waves in its wake, using up some energy that would otherwise send it surging ahead. But ducklings in the sweet spot experience 158 percent less wave drag than when swimming alone, the researchers calculated, meaning the duckling gets a push instead. (via Science News)
4. The smoke plume from the Dixie Fire—the largest single fire in California state history—got so huge it covered five states. It’s mostly contained now, but at its peak, people across some 2,500 square miles from California to Nebraska, were breathing in a variety of toxins from the materials that fuel the fire, including ozone, carbon monoxide, and particulate matter. As years of poor forest management and climate change cause fires to grow in size and intensity, it’s become increasingly important to understand how smoke affects animals, so that scientists can identify the most vulnerable species and determine whether they need management or conservation plans. Yet little is known about how wildfire smoke affects animals, and scientists are scrambling for answers. (via National Geographic)
5. Concerning news from Iceland: This fall, the Icelandic Institute of Natural History recommends a hunting quota of 20,000 ptarmigan, RÚV reports. Never in the Institute’s 16-year history of advisement has the ptarmigan population been smaller. An ornithologist working for the institute maintains that the population has dwindled in the long term. Rock ptarmigan are still hunted in Iceland as they are considered a delicacy, often consumed on Christmas Eve. Although the ptarmigan was granted protective status in 2003, its numbers have been steadily dwindling. This year, for example, the Icelandic Institute of Natural History recommends a hunting quota of 20,000 birds, which is 5,000 ptarmigan fewer than last fall (which, in turn, was a 35% decrease from 2019). (via Iceland Review)
6. Young birds that eat insects with conspicuous warning colouration to advertise their toxicity to would-be predators quickly learn to avoid other prey that carry the same markings. Developing on this understanding, a University of Bristol team have shown for the very first time that birds don't just learn the colours of dangerous prey, they can also learn the appearance of the plants such insects live on. To do this, the scientists exposed artificial cinnabar caterpillars, characterised by bright yellow and black stripes, and non-signalling fake caterpillar targets to wild avian predation by presenting them on ragwort and a non-toxic plant -- bramble, which is not a natural host of the cinnabar. Both target types survived better on ragwort compared to bramble when experienced predators were abundant in the population. (via Science Daily)
7. Well, probably worth a try: Amsterdam Airport Schiphol in the Netherlands has started a trial to figure out whether or not pigs can be of any help to keep birds at bay. Birds can be a nuisance for air traffic as collisions could damage plane engines. A group of 20 pigs will stay at a stretch of land of 2 hectares between 2 Schiphol runways, where recently sugar beet were harvested. The harvest remains are usually interesting for birds, predominantly geese and pigeons, however, can also be on the menu for pigs. During the trial the bird activity will be compared between the areas having pigs and another reference stretch without porcine inhabitants. The success rate will be determined using a special “bird radar,” which normally maps where birds abound in the wider Schiphol area, as well as visual observations. (via Pig Progress)
8. Innovative way to learn about birds: With larger-than-life cherries and tiny buildings popping up from vibrantly colored turf, the Douglass 18 miniature golf course might look like any other whimsical iteration of the game. But this one has a twist: Local teens designed this course to teach players about Chicago’s birds. Along with obstacles that show diet or habitat, each hole has a sign with a photo of a bird and some information about that species. As golfers place their balls on the turf at Hole 1 and line up their first shots, they’ve already been presented with a bird fact: the high mortality rate of American Robins, the hole’s namesake. Many songbirds face the same challenge. “After they leave the nest, about half of the American Robins alive in any year will make it to the next,” reads the sign. (via Audubon Magazine)
9. Climate change is leading to more frequent, intense storm events across the globe. The recently released report from the Intergovernmental Panel on Climate Change (IPCC) indicated that among other consequences of climate change, heavy rains fueled by warmer air will increase the number of deadly floods across the planet, a trend that many researchers say is already underway. Heavy rainfall can reduce foraging time for many bird species. Flying insects are inactive during heavy rain, so birds such as aerial insectivores – which are experiencing strong population declines across North America – are unable to find food during storms. This means that nesting birds have less food to feed their young, causing nestling growth to slow in insectivores, such as Tree Swallows, after heavy rains. (via Audubon)
10. Friends: I hadn’t expected to spend a week staring at Canada Geese with glee. But as I paid closer attention to them, I noticed an American Kestrel flying and then taking refuge in the garden bed, lurking. Then I saw another, and a third, and all together they kept vigil, occupying a bare tree. After breakfast they were gone, chased away by the raucous crows. When I stopped hoping for something "better" to appear around the corner, I noticed anew the majestic dihedral soaring of the Turkey Vulture scouting the woods for carrion, stopped at the comical sight of a gang of Wild Turkeys hanging out in a field (perhaps discussing the weather), and eavesdropped on the chatter of White-throated Sparrows punctuated by the incessant tapping of a Hairy Woodpecker. Watching these birds so closely, I felt that I was in the company of friends. It’s the common birds in front of us that are a gift we can’t afford to take for granted, but not only for reasons we may think. (via Audubon)
11. Fun: Hawks are now nesting in the atrium of Corson-Mudd Hall on the Cornell University campus. The two adult birds and one fluffy chick won’t even flinch when you move in for a closer look. This life-size sculpture is the work of David Cohen from Cape Cod, Massachusetts, a self-professed fan of Cornell’s red-tailed hawk family. The birds are superstars on the Lab of Ornithology’s live bird cams and have been nesting on a Tower Road light pole nearly every year since 2012. The sculptured scene represents the real female hawk, Big Red, and her previous mate, Ezra, named for university founder Ezra Cornell. The cam community was devastated when Ezra died in 2017 after sustaining injuries from a collision, perhaps with a nearby building or vehicle. For Cohen, this sculpture is a memorial based on a real-life scenario he can’t forget. (via Cornell Chronicle)
Bird Photo of the Week
Photo by Mike Hamilton, Migration.
Bird Videos of the Week
By National Geographic, “Watch an Endangered Philippine Eagle Chick Grow Up”. Endangered Philippine Eagle Chick - Nat Geo
Cornell Live Bird Cam - Kestrel Cam.
Cornell Live Bird Cam - Owl Chicks.