Loose Feathers #433

Short-eared Owl at Lacreek NWR / Photo Credit: Tom Koerner/USFWS

Birds and birding

• Many of you may already know that Hurricane/Superstorm Sandy breached the West Pond at Jamaica Bay Wildlife Refuge, so that what had been a freshwater pond became a brackish tidal pond. That breach has still not been repaired, and the National Park Service is still deciding what to do. Please sign this petition to ask that the NPS restore it as a freshwater pond.
• As tracking technology has gotten smaller, scientists have been able to follow the migration routes of more bird species. A new RSPB center will focus on this type of research.
• Labrador Duck may have been a hybrid rather than a separate species. If so, it would not be the first time that a species described by John James Audubon turned out not to be a species. Someone needs to do some genetic analysis on this.
• The tail shapes of diving birds may have evolved to support their foraging style.
• Male Chipping Sparrows will sometimes assist nearby males in driving off intruders, but only if the neighbor is a weaker bird.
• Some flowers have evolved colors to match the visual systems of pollinating birds like honeyeaters.
• Habitat loss causes kestrels to live shorter and more stressful lives, and as a result they need to start breeding earlier in life.
• Green roofs in New York City have turned into a haven for insects and birds.
• The Great Backyard Bird Count received data from a record 131 countries.

Science and nature blogging

• Birding the day away !!: Topography
• Laelaps: Giant Prehistoric Bird Crushed Seeds, Not Little Horses
• 10,000 Birds: Restore the West Pond!
• Idaho Bird Observatory: The Northern Goshawk in Biogeographical Context
• Not Exactly Rocket Science: The Tiny Culprit Behind A Graveyard of Ancient Whales
• Bird Ecology Study Group: Chestnut-headed Bee-eater - conflict (social behaviour)
• Outside My Window: Bird Skeletons As Heavy As Mammals’
• PhotoNaturalist: Introduction to Insect Macro Photography (Part II) - How to Approach Insects
• The Rattling Crow: The bill of the blackbird
• Extinction Countdown: The Long, Strange Saga of the Endangered Hawaiian Hawk

Environment and biodiversity

• California received some heavy rain this week (with more on the way), but it still has far to go to recover from the severe drought.
• Like other Bronze Age civilizations, the collapse of the Indus (or Harappan) Civilization may have been triggered by climate change.
• Contaminated soil is likely to be dumped on a newly remediated site near the Rahway River thanks to the political machinations of the Christie administration and Democratic political bosses.
• Conservationists and activists need to focus on more than one company or pesticide for the cause of Monarch butterfly declines. (The same goes for other pollinator declines, really.)
• Combined with climate change, desert solar plants may raise the ambient temperature too high for desert tortoises.
• Ignoring ocean conservation has serious consequences.

Loose Feathers #432

Northern Pintails in flight / Photo by J. Kelly (USFWS)

Birds and birding

• The opening of the Ivanpah solar energy plant led some reporters to investigate what conservationists have realized for some time: the siting and design of the plant causes a huge cost in wildlife.
• Manu National Park in Peru is one of the world's greatest biodiversity hotspots, with over 1,000 species of birds and 287 reptiles and ampibians recorded within the reserve.
• The London Array of wind turbines in the Thames Estuary will not be expanded due to concerns about its impact on Red-throated Loons.
• The Great Backyard Bird Count has documented the spread of Eurasian Collared Doves.
• Birds that depend on shallow or clear water have trouble in floods.
• Scientists have attached a tracking device to one of the few remaining Great Indian Bustards.
• A father and son in Wisconsin were charged with poisoning wildlife, including two Bald Eagles.

Science and nature blogging

• All About Birds: Climate Change Pushing Tropical Birds Up the Mountain…and Off
• California WaterBlog: Saving California’s salmon during a severe drought
• Bourbon, Bastards, and Birds.: Often Sought, Often Misidentified: The Thayer's Gull
• Anything Larus: Slaty-backed Gull: Lake County Fairgrounds
• South Jersey Butterfly B/Log: Let the winter winds blow — these are tough cats!
• Extinction Countdown: Sunday Species Snapshot: Blue-Crowned Laughingthrush

Environment and biodiversity

• A study found substantial evidence of bears using the wildlife crossings of the Trans-Canada Highway in Banff National Park. Most importantly, it has prevented the populations on either side of the highway from becoming genetically isolated.
• Excessive melting of Arctic sea ice has made the Arctic Ocean 8% darker, which contributes to greater warming of the Arctic.
• The Carolina Satyr was split into three species based on specimens from Texas.
• A free ebook on ants, Dr. Eleanor’s Book of Common Ants of New York City, became available this week. 
• Washington, DC, is digging a massive tunnel under the city to solve the problem of raw sewage getting washed into rivers during rainstorms.
• Excessive runoff containing road salt elevates chloride levels in nearby wetlands, which can be toxic to aquatic organisms.
• While this winter has been exceptionally harsh compared to recent winters in the eastern United States, much of the rest of the world is having an unusually warm January and February.
• The Sochi Olympics provide a model of what not to do in terms of their environmental impacts. Meanwhile a Russian environmentalist who brought the environmental problems to wider attention was sentenced to three years in prison.
• Here is another article on the work towards understanding the Late Permian extinction event.
• A study found that wild bumblebees are able to catch diseases like Nosema from domesticated honeybees.
• Leaf litter helps keep eastern red bats warm in the winter.
• This week a Nebraska judge invalidated the governor's approval of the Keystone XL pipeline route through the state.
• Americans still support the Endangered Species Act despite relentless political attacks on it.

Photos of the Week: Red-necked Grebe

Red-necked Grebe is the most difficult to find of the three grebes that regularly visit the eastern coast of North America. Pied-billed Grebes are fairly common on inland waterways, especially during their migration, and Horned Grebes are easy to find along the coast. Red-necked Grebes are another matter since most of them winter around the Great Lakes or Canada's Maritime provinces. To see one in the Mid-Atlantic, you either need to get lucky or know a location where one is reliable.

On Saturday, I got lucky and found one along the Raritan River at Edison Boat Basin. What started as a search for unusual gulls instead turned up an unusual grebe. It started snowing furiously around the same time I spotted the grebe, so the white specks in these photos are snowflakes. Red-necked Grebe is noticeably larger than the other common eastern grebes. It is easily recognizable among grebes because of its long, loon-like bill.

While this species is uncommon here, seeing one on Saturday was not entirely surprising. The persistent cold of this winter has frozen many waterways further north and is pushing many waterbirds south of their normal wintering grounds. This is especially true of Red-necked Grebes and White-winged Scoters, and there have been several reports of Red-necked Grebes around New Jersey in recent weeks. Perhaps I will find a White-winged Scoter soon too.

Loose Feathers #431

Sanderlings / Photo by Bill Buchanan (USFWS)

Birds and birding

• The evolution of more diverse melanosomes (which create more colorful plumage, among other things) may have been a precondition for the evolution of flight.
• A 50-year project has documented the unique facial patterns of Bewick's Swans.
• New York City Audubon wants to restore the West Pond at Jamaica Bay Wildlife Refuge as a freshwater pond for migratory birds.
• Snowy Owls have been tracked hunting on the ice that covers Lake Erie. Presumably they are preying on sea ducks that gather in gaps in the ice.
• Tufted Puffin populations in the Pacific Northwest have declined 90% in the last 30 years.
• Great Tits can observe and remember where other birds cache food.
• Albania has instituted a two-year moratorium on hunting birds and mammals to enact more effective hunting regulations and give wildlife populations a chance to recover.
• Two endangered Whooping Cranes were shot in Louisiana last week.
• In better news, Wisdom the Laysan Albatross hatched another chick at age 63. She is the oldest known wild bird.
• The Yellow-eyed Penguin forages by following lines carved in the seafloor by fishing boats.

Science and nature blogging

• Myrmecos: On The Other Hand, Bumble Bees Are In Trouble
• Charismatic Minifauna: I Promise: Spiders are Not Trying to Kill You.
• Bird Ecology Study Group: Yellow-vented Bulbul caught in a spider’s web
• Lyman Entomological Museum: Look up, way up: beetles and flies in the tree tops
• 10,000 Birds: What is a Nictitating Membrane?
• The Rattling Crow: The scary bright eyes of the Jackdaw
• Extinction Countdown: Manumea Found: Strange Bird Seen Breeding for the First Time in a Decade 
• Birding Dude: The Conundrum of Identifying Sharp-tailed Sparrows to Subspecies in the Field

Environment and biodiversity

• OnEarth Magazine explains the problems with the USFWS's decision to move forward with delisting gray wolves. Among other things, the USFWS considers eastern wolves to be a separate species (something few scientists outside the USFWS agree with) and therefore not part of the gray wolf's historic range. Another analysis is here.
• The scientist who found that atrazine harms amphibians faced a relentless smear campaign from the herbicide's manufacturer, on a scale similar to what climate scientists face.
• The migration of whales off of California may set a new record this month.
• A study estimates that the mass extinction at the end of the Permian occurred in just 60,000 years.
• There may be a link between zebra mussel activity and algae blooms because the invasive mussels add nutrients to the water column.
• Charles Darwin was born 205 years ago this week. In honor of that occasion a beetle that he collected was finally identified as belonging to a new genus and species in a paper published this week.
• New Jersey may lose funding for trail maintenance because the DEP has been tardy in administering the funds.
• Like eastern states, Michigan faces the problem that much of its air and water pollution comes from outside the state.
• North Carolina intervened to protect Duke Energy from water pollution lawsuits.
• A new plant discovered in the Andes supports 40-50 insect species.
• California's drought might be the worst in several centuries.
• Next week is the 20th anniversary of an executive order that required federal agencies to account for effects on people of color when they issue regulations, a major goal of the environmental justice movement.
• Maryland wants to enact a tax on poultry farms to help pay for Chesapeake Bay cleanup. Poultry farms are a major contributor to nutrient runoff in the Chesapeake watershed.
• Getting action to curb ocean acidification seems unlikely in the near term, but some experimental projects might make a small improvement.
• Warm temperatures in Sochi this week are a reminder that winter sports will soon face a dearth of reliable ice and snowpacks. Of the 19 cities to host the Winter Olympics, only 10 would likely have a suitable climate to host them by 2050, and only 6 by 2100.
• The extinction of large mammals at the end of the last Ice Age may be linked to large-scale vegetation changes that were driven by climate change.
• While the farm bill is terrible in many respects, the latest version includes improvements in funding for conservation programs.
• The Ivanpah desert solar plant officially opened this week.
• Satellite technology can be used to identify and count individual whales.

The Aerodynamics of Diving Peregrines

Falcons are well known for their speed and agility. They prey primarily on other birds and generally catch their prey on the wing. (Small falcons like kestrels often eat large insects or small rodents in addition to birds.) All falcons are sleek with pointed wings and capable of fast flight, but Peregrine Falcons in particular are noted for their high-speed dives. I have been fortunate to witness such dives on several occasions, and they remain impressive every time. A recent paper in PLoS ONE examines the aerodynamics of diving Peregrine Falcons through a series of experiments.

A typical sequence of images taken during a dive at the selected points. Source: PLoS ONE

Peregrines were trained by falconers to dive in front of the south wall of a dam to allow high-speed cameras to capture their flight shape and trajectory precisely. The resulting photographs were then used to build a model for wind tunnel testing.

Flow visualization on the surface of the falcon model (A) and the falcon at the same flight position (B). Source: PLoS ONE

At the top of the dive, the falcon initially accelerated and then flew at constant speed with its wings tucked into a diamond shape. During this dive, the falcon reached a maximum speed of about 50 mph. As it approached its intended prey, it spread its wings to generate lift and rapidly decelerated, finally pulling out of its dive and landing. The wind tunnel tests showed several regions where the airflow was uneven around the model. At one such region, near where the trailing edge of the wing is tucked close to the body, photographs showed feathers popped up to smooth the airflow.

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Benjamin Ponitz, Anke Schmitz, Dominik Fischer, Horst Bleckmann, & Christoph Brücker (2014). Diving-Flight Aerodynamics of a Peregrine Falcon (Falco peregrinus) PLoS ONE DOI: 10.1371/journal.pone.0086506