Pileated woodpeckers, big North American birds


This 24 April 2021 video says about itself:

The PILEATED WOODPECKER | The LARGEST in North America!

Except for the Ivory-Billed which certainly seems to be extinct, and the Imperial which hasn’t been seen since the 90s. In this video learn more about what Pileated Woodpeckers eat, where to find one, things you can do if they are damaging your home, and even how to pronounce Pileated.

Attracting Northern Cardinals in North America


This 19 February 2021 video from the USA says about itself:

Northern Cardinals are perhaps the most conspicuous and familiar songbirds across their range in the eastern United States and Mexico. Let’s focus on what types of seeds and feeders are best to attract these year-round residents to the bounty of your backyard bird feeders.

North American marbled murrelets in trouble


This 20 April 2020 video says about itself:

In Search of an ENDANGERED Bird: Scouting Marbled Murrelet Training Sites. Wildlife Biology VLOG

Despite the pandemic, the need to monitor endangered species continues. In this wildlife biology vlog, I share my journey scouting out new sites to safely train new marbled murrelet surveyors this coming field season. Murrelets are simply incredible animals, and seeing them again was a much-needed breath of life.

From Oregon State University in the USA:

Warming ocean, old-forest loss put a squeeze on an elusive seabird

September 22, 2020

Squeezed by changing ocean conditions that limit their food options and the long-term loss of old forest needed for nesting, marbled murrelets would benefit most from conservation efforts that take both ocean and forest into account, new research by Oregon State University shows.

Published in Conservation Letters, the findings are based on two decades of murrelet surveys at nearly 20,000 sites in the Oregon Coast Range and illustrate how the elusive seabird is at risk of its habitat gradually shrinking to the point of local extinctions or worse.

“It turns out that the same ocean conditions that influence salmon returns, including the forage fish murrelets need to successfully nest, had a huge influence on the likelihood that murrelets will come inland to breed,” said lead author Matt Betts, a researcher in the Oregon State College of Forestry and the director of the OSU-based Forest Biodiversity Research Network. “Given that these prey items tend to be in lower abundance when ocean temperatures are high, changing climate conditions could reduce prey availability as well as the tendency for murrelets to nest in the future.”

Marbled murrelets are closely related to puffins and murres, but unlike those birds, murrelets raise their young as much as 60 miles inland in mature forests. Disturbance in either the ocean or forest environment has the potential to impact murrelet populations.

“There aren’t many species like it,” said study co-author and project director Jim Rivers, also a faculty member in the College of Forestry. “There’s no other bird that feeds in the ocean and commutes such long distances inland to nest sites. That’s really unusual.”

The dove-sized bird spends most of its time in coastal waters eating krill, other invertebrates and forage fish such as herring, anchovies, smelt and capelin. Murrelets can only produce one offspring per year, if the nest is successful, and their young require forage fish for proper growth and development.

Murrelets generally nest in solitude, although multiple nests sometimes occur within a small area. They typically lay their single egg high in a tree on a horizontal limb at least 4 inches in diameter, with Steller’s jays, crows and ravens the main predators of murrelet nests.

“The end goal for these birds is to be very secretive and quiet so predators don’t find their nests and they can produce young,’ said Rivers.

Along the West Coast, marbled murrelets are found regularly from Santa Cruz, California, north to the Aleutian Islands. Their populations have been declining by about 4% a year in Washington, Oregon and California, and the species is listed as threatened under the U.S. Endangered Species Act in those states.

“Early on in our work, we noticed strong fluctuations in the numbers of marbled murrelets coming inland to nest, so this study was about trying to get to the bottom of those highs and lows,” Betts said. “We found the first evidence that ocean conditions combined with old-forest nesting habitat influence the murrelets’ long-term occupancy dynamics. In particular, we learned ocean conditions are a key driver of those dynamics.”

The finding has potential key implications for forest policy in Oregon, where any state-owned site that goes two consecutive years without murrelet detection is classified as unoccupied and thus available for timber harvest.

“Our data show that below-average ocean conditions might last for more than two successive years,” Rivers said. “That means there could be a scenario where sites on state lands that are suitable for breeding go unused for more than two years which, under current guidelines, would let them be considered available for harvest. Thus, murrelets might be missing from inland sites not because the forest is unsuitable for nesting, but because they have inadequate forage fish during the summer breeding season. That means it is critical that we consider factors that influence both marine food resources and terrestrial nesting habitat when considering how to recover murrelet populations.”

Betts was part of a research collaboration that published a 2019 paper in the Proceedings of the National Academy of Sciences that showed that old forest is still declining across the Pacific Northwest 25 years into the Northwest Forest Plan, a 100-year federal road map to protect older forests.

“This is now less due to the saw and more due to fire,” he said. “That means that even with strong land conservation measures, climate could not only result in warmer ocean conditions but also greater fire frequency and extent, and therefore more old forest loss.”

Other Oregon State researchers contributing to the study were Kim Nelson and Dan Roby of the College of Agricultural Sciences and Jennifer Fisher of the Cooperative Institute for Marine Resources Studies. Scientists from Trent University in Ontario, Canada, the University of Rhode Island and the U.S. Forest Service also took part.

The OSU College of Forestry and the USDA National Institute of Food and Agriculture provided funding.

Columbine flowers, new research


This 26 April 2020 video says about itself:

Learn all the information you need to grow Columbine Flowers, aka Wild Columbine, aka Eastern Red Columbine, Aquilegia canadensis.

Grow this hardy perennial (USDA zones 3-8) in full sun to shade. Columbine will grow just about anywhere as long as the soil drains well. But in this video, I teach you how to germinate columbine seeds, save seeds, identify Columbine, and numerous other tips from pests to diseases and how to avoid them. I also show you just how much Columbines spread. I hope you like it, and please ask any questions in the comments!

We have a very detailed article on this flower here.

From the University of California – Santa Barbara in the USA:

Biologists discover gene critical to development of columbines‘ iconic spurs

August 24, 2020

Once in a while, over the history of life, a new trait evolves that leads to an explosion of diversity in a group of organisms. Take wings, for instance. Every group of animals that evolved them has spun off into a host of different species — birds, bats, insects and pterosaurs. Scientists call these “key innovations.”

Understanding the development of key innovations is critical to understanding the evolution of the amazing array of organisms on Earth. Most of these happened deep in the distant past, making them difficult to study from a genetic perspective. Fortunately, one group of plants has acquired just such a trait in the past few million years.

Columbines, with their elegant nectar spurs, promise scientists an opportunity to investigate the genetic changes that underpin a key innovation. After much research, UC Santa Barbara professor Scott Hodges, research associate Evangeline Ballerini, and their coauthors at Harvard University have identified a gene critical to the development of these structures. And to their knowledge, this is among the first key innovations for which a critical developmental gene has been identified. Their findings appear in the journal PNAS.

The researchers named the gene after Gregg Popovich, head coach of the San Antonio Spurs basketball team. “This gene is a transcription factor, which means it controls spur development in columbines by regulating the activity of other genes,” explained Ballerini. “So I chose the name POPOVICH because as coach, Popovich controls San Antonio Spurs development, in a sense, by regulating the activity of his players.”

The evolution of spurs in columbines’ ancestors seems to have led to rapid expansion in the genus. Around 70 species evolved over the past 5 to 7 million years, compared to its spurless sister genus, which counts only four species among its members.

And columbines aren’t the only flowers with spurs. The trait evolved independently in many different plants, including nasturtiums, larkspurs and impatiens. “And in each of those groups, the ones that have spurs have far more species than their closest relatives that don’t have spurs,” said Hodges.

“We think that diversity is linked to the evolution of this spur because the spur produces nectar, which attracts animal pollinators,” Ballerini said. Changing the length or shape of the spur changes the animals that can pollinate the flower. “Bees are only moving pollen between bee flowers, hummingbirds are only moving pollen between hummingbird flowers, so you’re not exchanging genes between those two different populations.” Eventually, the two can split into different species.

The question the researchers were trying to answer was how innovations like these develop in the first place. “If we can find genes that are important in the development of a key innovation, that will help us understand this kind of process,” said Hodges.

“In most of these cases — like in the wing example with birds, bats and insects — those evolved so long ago that it’s hard to find a particular gene that was critical for evolving that trait,” he added. “Here we have a fairly recent origin of a key innovation, only 5 to 7 million years ago, and it’s a fairly simple trait, so it’s a little more straightforward.”

Finding POPOVICH

Since columbines evolved so recently, most of them can form fertile hybrids with each other. In the 1950s and ’60s, a Polish geneticist crossed a spurless species — appropriately named the spurless columbine — with its spurred cousins. She found that in the first generation of offspring all had spurs, but self-pollinating these yielded a second generation where spurlessness reappeared in a quarter of the plants.

That ratio was crucial to Hodges and Ballerini’s work some half a century later. This simple fraction suggested that a single gene controlled the development of spurs. But columbines have roughly 30,000 genes, and only one was the gene they were looking for.

Following in the footsteps of his predecessor, Hodges also crossed the spurless columbine with a spurred species, and then self-pollinated the offspring. But unlike in the previous experiment, Ballerini and Hodges now had the tools to search the plants’ genetic code.

Ballerini sequenced the genome of each of the nearly 300-second generation plants and looked for instances in which the spurless plants had inherited two copies from their spurless grandparent. This narrowed the search to around 1,100 genes on one of the plants’ chromosomes.

Still, 1,100 genes are a lot to sort through. “There was no guarantee that these methods would lead us to the gene we were looking for,” Ballerini said. “There was definitely quite a bit of work that went into all of the experiments and analyses, but in the end, there was a bit of luck too.”

Ballerini examined the expression of genes during five stages of early petal development in the spurless columbine and three other spurred species. She sequenced all the genes that were turned on in each stage and looked for consistent differences between the spurless and spurred plants. Eventually, with input from one of her collaborators at Harvard, Ballerini suspected she had identified the right gene. It was always turned off in the spurless species, turned on in the spurred species and was one of the 1,100 genes previously identified as associated with spurless flowers in the genetic cross. Now it was time to test her hypothesis.

She used a genetically modified virus to knock down the expression of the gene in question as well as a gene critical for producing red pigment. This way they could tell which petals were affected just by looking at the color.

Wherever POPOVICH was sidelined, the flowers developed diminutive spurs. But spur length depends both on the number and the size of cells. So the researchers worked with collaborators to count the number and measure the length of each cell making up these diminutive spurs.

“The longer spurs had more cells, and the shorter spurs had fewer cells,” Hodges noted. “So the gene must have been acting by affecting how many cells were produced.”

Ballerini remembers sitting in her office after finishing her final analyses. She began throwing out potential gene names to graduate student Zac Cabin, a fellow sports enthusiast. “At the same time Zac and I turned to each other and both said ‘POPOVICH!'” she recalled. The name seemed a perfect fit. “And it leaves open the possibility that, if we identify other genes at play in spur development, we can name them after some of the players on the Spurs.”

A path to new discoveries

While identifying POPOVICH is certainly an achievement, the true value of the discovery lies in what it reveals about the evolution of key innovations. Before this work, none of the plant groups that had well-known genomes also made spurs. “We had no idea where to start,” said Hodges. “This discovery provides us a foothold.”

“Once we identify one gene — like this gene, which seems to be key in the process of forming spurs — then we can start to figure out all of the components,” he added. The team can now begin investigating which genes POPOVICH regulates, and which genes regulate POPOVICH. “This is a place to start to understand the whole system.”

While the researchers don’t know how POPOVICH functions in other groups of plants, it appears to influence the number of leaflets that grow on bur clovers. Columbines also express the gene in their leaves; perhaps it was recruited from the leaves into petal development, Ballerini suggested.

Novel adaptations don’t appear out of nowhere, she explained. “When you’re evolving a new structure, usually you’re not evolving a whole brand new gene.” Generally, organisms repurpose or add a purpose to an existing gene.

The authors are also interested in identifying genes involved in the second phase of spur formation: the elongation of the cells in the spur cup.

“These are things that we will want to do now that we’ve identified this gene,” Hodges said. “And since it’s a transcription factor, it must have particular genes that it’s affecting. The next logical step would be to identify the targets of this gene, and that would tell us a lot more about how it functions.”

The researchers expressed their gratitude toward Harvey Karp, who generously funded the Karp Discovery Award that made their research possible. “We really couldn’t have done this project without it,” Ballerini said.

Golden-winged and blue-winged warblers, new research


This 2011 video from the USA says about itself:

Blue-winged and Golden-winged Warblers and Hybrids in Connecticut. ©JimZipp.com

Note that the Blue-winged has yellowish wingbars and the Golden-winged sings a Blue-winged song. Lots of interbreeding in this area and Golden-winged Warblers are rarer every year.

From Penn State University in the USA:

What determines a warbler’s colors?

Researchers use hybrid birds to narrow genetic region underlying difference in color between blue-winged and golden-winged warblers

July 14, 2020

A new study has narrowed down the region of the genome that drives the black color in throat and face of warblers by studying the hybrid offspring produced when two species mate. The hybrids of golden-winged and blue-winged warblers have a mix of coloration from the parent species, which allows researchers to identify which regions of the genome are associated with which color patterns. The study, led by researchers at Penn State, also reveals a more complex basis for the amount of yellow in warbler bellies and raises concerns about how hybrids of these species are classified.

Their results appear online in the journal The Auk: Ornithological Advances.

“The distinct plumage of these otherwise very similar birds has perplexed ornithologists for more than a hundred years,” said Marcella Baiz, postdoctoral researcher at Penn State and first author of the paper. “Our research team previously compared the genomes of golden-winged and blue-winged warblers and identified 6 regions that differed between them, some of which may control color. In this study, we used hybrid birds of these species, which mix and match the features of their parent species, to help identify which regions of the genome are associated with which color patterns.”

Color is an important cue for warblers and is prominently displayed during mating and other behaviors. Blue-winged warblers have yellow throats and bellies, while golden-winged warblers have white bellies and a black throat patch and face mask. Hybrids of these species vary in amounts of yellow and whether they have a black face mask and throat, and these characteristics are commonly used to categorize birds into different classes of hybrids.

The research team rated hybrid birds based on their plumage color and genetic likeness to the two parental species. They found that the amount of yellow in hybrids, which is produced by pigments called carotenoids, is not directly related to a bird’s genetic likeness to the parent species — for example, hybrids with more yellow were not genetically closer to blue-winged warblers. Additionally, the extent of yellow in hybrids re-captured in subsequent years appeared to decline over time.

“Some researchers have hoped that the extent of yellow could indicate how many generations a hybrid is removed from the parent species,” said David Toews, assistant professor of biology at Penn State and leader of the research team. “Our results indicate that it isn’t quite so straightforward, and that classifying hybrids into groups based on the amount of yellow can be misleading.”

The inheritance of a black throat patch and face mask, however, appears to be much more straightforward. The research team previously identified a genetic region related to black coloration in warblers. In the current study, the team used a rarer type of hybrid to narrow that to a region about five times smaller.

“This one type of very rare hybrid looks almost entirely like a blue-winged warbler, with a yellow body but with a black throat patch and face mask, like a golden-winged warbler,” said Baiz. “By comparing its genome to that of blue-wing warblers, we were able to identify a much smaller genetic region where the birds differed, which we believe drives the black coloration.”

The genetic region is located near the Agouti-signaling protein (ASIP) gene, which is thought to regulate production of the pigment melanin in some birds. Next, the research team would like to confirm that this section of the genome affects expression of the ASIP protein in warblers and underlies differences in their black plumage patches.

“We plan to continue to study the evolution of color across the 110 species of warblers, which have incredibly diverse plumage,” said Toews. “Now that we have identified a starting point, this narrowed down genetic region, we won’t be stabbing in the dark.”

In addition to Baiz and Toews, the research team includes Gunnar Kramer and Henry Streby from the University of Toledo, Scott Taylor from the University of Colorado, Boulder, and Irby Lovette from the Cornell Lab of Ornithology. This research was supported by the Cornell Lab of Ornithology, the U.S. Geological Survey, and the National Science Foundation.

New list of American bird species


This is a video about a turquoise-browed motmot in Costa Rica.

From the American Ornithological Society Publications Office:

Goodbye northwestern crow, hello Mexican duck

Updates to the official list of North and Central American bird species

June 30, 2020

The latest supplement to the American Ornithological Society’s Checklist of North and Middle American Birds, published in The Auk: Ornithological Advances, includes several major updates to the organization of the continent’s bird species, including the addition of the Mexican Duck and the removal of the Northwestern Crow. The official authority on the names and classification of the region’s birds, the checklist is consulted by birdwatchers and professional scientists alike and has been published since 1886.

The Northwestern Crow has long been considered a close cousin of the more familiar and widespread American Crow, with a range limited to the Pacific Northwest. However, a recent study on the genetics of the two species prompted AOS’s North American Classification Committee to conclude that the two species are actually one and the same. “People have speculated that the Northwestern Crow and the American Crow should be lumped for a long time, so this won’t be a surprise to a lot of people,” says the U.S. Geological Survey’s Terry Chesser, chair of the committee. “Northwestern Crows were originally described based on size, being smaller than the American Crow, and behavior, but over the years the people who’ve looked at specimens or observed birds in the field have mostly come to the conclusion that the differences are inconsistent. Now the genomic data have indicated that this is really variation within a species, rather than two distinct species.”

However, birdwatchers disappointed to lose the Northwestern Crow from their life lists can take solace in the addition of a new species to the official checklist: the Mexican Duck. “The checklist recognized Mexican Duck until 1973, when it was lumped with Mallard,” says Chesser. “But the Mexican Duck is part of a whole complex of Mallard-like species, including Mottled Duck, American Black Duck, and Hawaiian Duck, and all of those are considered distinct species except for, until recently, the Mexican Duck. Now genomic data have been published on the complex and on the Mexican Duck and Mallard in particular, and they show that gene flow between them is limited, which was enough to convince the committee to vote for the split.”

Additional changes introduced in this year’s checklist supplement include a massive reorganization of a group of Central American hummingbirds known as the emeralds — adding nine genera, deleting six others, and transferring seven additional species between already-recognized genera — as well as an update to the criteria for adding introduced, non-native species to the list that raises the bar for introduced species to officially be considered established.

North American migratory birds, video


This 10 June 2020 video from the USA says about itself:

More than half of the migratory bird species in North America are declining. In order to conserve these migrating birds, conservation scientist and National Geographic explorer Kristen Ruegg is tracking bird DNA with the Bird Genoscape Project.

American robin migration and climate change


This 2019 video from the USA is called 5 Lovable Things About American Robins.

From the Earth Institute at Columbia University in the USA:

American robins now migrate 12 days earlier than in 1994

New GPS data show birds adjust to shifting snow conditions as climate warms

April 1, 2020

Summary: A new study concludes that robin migration is kicking off earlier by about five days each decade. The study is also the first to reveal the environmental conditions along the migration route that help the birds keep up with the changing seasons.

Every spring, American robins migrate north from all over the U.S. and Mexico, flying up to 250 miles a day to reach their breeding grounds in Canada and Alaska. There, they spend the short summer in a mad rush to find a mate, build a nest, raise a family, and fatten up before the long haul back south.

Now climate change is making seasonal rhythms less predictable, and springtime is arriving earlier in many parts of the Arctic. Are robins changing the timing of their migration to keep pace, and if so, how do they know when to migrate? Although many animals are adjusting the timing of their migration, the factors driving these changes in migratory behavior have remained poorly understood.

A new study, published in Environmental Research Letters, concludes that robin migration is kicking off earlier by about five days each decade. The study is also the first to reveal the environmental conditions along the migration route that help the birds keep up with the changing seasons. Lead author Ruth Oliver completed the work while earning her doctorate at Columbia University’s Lamont-Doherty Earth Observatory.

At Canada’s Slave Lake, a pit stop for migrating birds, researchers have been recording spring migration timing for a quarter-century. Their visual surveys and netting censuses revealed that robins have been migrating about five days earlier per decade since 1994.

In order to understand what factors are driving the earlier migration, Oliver and Lamont associate research professor Natalie Boelman, a coauthor on the paper, knew they needed to take a look at the flight paths of individual robins.

Their solution was to attach tiny GPS “backpacks” to the birds, after netting them at Slave Lake in mid-migration. “We made these little harnesses out of nylon string,” Oliver explained. “It basically goes around their neck, down their chest and through their legs, then back around to the backpack.” The unit weighs less than a nickel — light enough for the robins to fly unhindered. The researchers expect that the thin nylon string eventually degrades, allowing the backpacks to fall off.

The researchers slipped these backpacks onto a total of 55 robins, tracking their movements for the months of April through June. With the precise location from the GPS, the team was able to link the birds’ movements with weather data on air temperature, snow depth, wind speed, precipitation, and other conditions that might help or hinder migration.

The results showed that the robins start heading north earlier when winters are warm and dry, and suggest that local environmental conditions along the way help to fine-tune their flight schedules.

“The one factor that seemed the most consistent was snow conditions and when things melt. That’s very new,” said Oliver. “We’ve generally felt like birds must be responding to when food is available — when snow melts and there are insects to get at — but we’ve never had data like this before.”

Boelman added that “with this sort of quantitative understanding of what matters to the birds as they are migrating, we can develop predictive models” that forecast the birds’ responses as the climate continues to warm. “Because the timing of migration can indirectly influence the reproductive success of an individual, understanding controls over the timing of migratory events is important.”

For now, it seems as though the environmental cues are helping the robins to keep pace with the shifting seasons. “The missing piece is, to what extent are they already pushing their behavioral flexibility, or how much more do they have to go?” said Oliver.

Because the study caught the birds in mid-migration, the tracking data doesn’t reflect the birds’ full migration path. To overcome this limitation, the researchers plan to analyze tissue from the robins’ feathers and claws, which they collected while attaching the GPS harnesses, to estimate where each bird spent the previous winter and summer.

Over the long term, Oliver says, she hopes to use the GPS trackers to sort out other mysteries as well, such as how much of the change in migration timing is due to the behavioral responses found in the study versus natural selection to changing environments, or other factors.

“This type of work will be really cool once we can track individuals throughout the course of their life, and that’s on the near-term horizon, in terms of technological capabilities,” she said. “I think that will really help us unpack some of the intricacies of these questions.”

The new study is part of a broader NASA-funded research and outreach project, called the Arctic-Boreal Vulnerability Experiment, that is tracking how the rapid warming of the far north affects wildlife. Read more about the project on the researchers’ blog: https://earthobservatory.nasa.gov/blogs/fromthefield/2016/04/12/a-migration-mystery/

Oliver is now a postdoctoral associate at Yale University. Other authors on the study include Peter Mahoney from the University of Washington, Eliezer Gurarie from the University of Washington and the University of Maryland, Nicole Krikun from the Lesser Slave Lake Bird Observatory, Brian Weeks from the University of Michigan, Mark Hebblewhite from the University of Montana, and Glen Liston from Colorado State University.

With the western United States and northern Mexico suffering an ever-lengthening string of dry years starting in 2000, scientists have been warning for some time that climate change may be pushing the region toward an extreme long-term drought worse than any in recorded history. A new study says the time has arrived: a megadrought as bad or worse than anything even from known prehistory is very likely in progress, and warming climate is playing a key role. The study, based on modern weather observations, 1,200 years of tree-ring data and dozens of climate models, appears this week in the leading journal Science: here.