City Lights Throw Migrating Birds Off Course

New research out of the University of Windsor indicates that bright city lights may cause migrating birds to zigzag rather than follow the (darker) course they might otherwise take. 

The team, headed by professor Dan Mennill, began their research by accident. Sound recording boxes had been placed around the area during a migration study, and the team noticed that the ones situated near well-lit—urban—areas picked up more bird vocalizations than the ones in dark—rural—ones. Further analysis revealed that more than three times the number of vocalizations occurred in the lit areas than in the unlit areas, indicating that three times more birds passed through the former than through the latter. Why? Perhaps because the lights made it difficult for them to see the stars by which they'd ordinarily navigate. 

Being drawn off course causes two problems for migrating birds. First, flying a less-than-direct route uses more of a bird's energy stores than flying a direct route; therefore, birds arriving at their destination are more depleted than they ought to be. Second, flying in a zigzag takes longer than flying directly, which means birds arrive later than they otherwise would—and perhaps miss a key food source or mating period. 

What can we do to help restore natural migration routes? For starters, we can turn off any unnecessary outdoor lighting at night. Mennill's team is researching other options, such as changing the intensity of street lights. Whatever they come up with, we're all for it. 

Sacrifice Mosquitoes to Rescue Hawaii's Birds?

Paradise would not be paradise without birds. Unfortunately, Hawaii's native bird population has been dwindling since the accidental introduction of mosquitoes in 1826 by a whaling vessel that dumped maggots into a stream on Maui. With mosquitoes came avian malaria, and with avian malaria came bad news for Hawaii's native birds, which had never encountered any disease like it. The U.S. Geological Survey is now saying that extinction seems to be imminent for some native species, especially on the island of Kawaii, which does not have mountains into which birds can retreat from mosquitoes. 

The Hawaiian archipelago is separated by 2,500 miles from the nearest land. It possesses a diversity of species even greater than the Galapagos Islands; and, like on the Galapagos, these organisms developed in such isolation that they weren’t adapted to the threats brought by Western explorers and immigrants. These days, 434 species of plants and animals are listed as endangered by the United States. More than half the native forest birds are already extinct.

A proposed solution is to create mosquitoes genetically engineered to die off before they reach reproductive age. A group of government officials, conservationists, and scientists in Hawaii are discussing the viability of such an idea. The U.S. Fish and Wildlife Service, which is responsible for endangered species, recently said it was looking at different recovery plans for forest birds. Among these is the mosquito method. 

A decade ago, the U.S. Fish and Wildlife service estimated the cost would be $2.5 billion over 30 years to preserve Hawaii's native forest birds. These plans included buying land and restoring habitats. But genetically modified mosquitoes could be much less expensive.

This is not to say that Hawaiians—or we here at Talkin' Birds, for that matter—are easy with the thought of genetically tinkering with nature. But the fact remains that mosquito technology is a potential fix for human diseases such as Zika. Currently, fighting human disease gets the attention and the funding, but conservation could become just as important a use of this biotechnology.

 

The Dodo May Not Have Been a Dodo

The word "dodo" has long been a synonym for "stupid." In fact, "dodo" comes from "doudo," the Portuguese word for "stupid." The large, flightless Dodo bird (Raphus cucullatus), once native to the Indian Ocean island of Mauritius, went extinct about 400 years ago, less than 100 years after it was discovered by humans. Popular culture blames the bird. However, new research suggests that the Dodo might have been at least as smart as the pigeons to which it was related.

In a recent article in the Zooligical Journal of the Linnean Society Dr. Eugenia Gold and her team at the National Museum of Scotland and the Natural History Museum of Denmark describe how they went about reimagining the Dodo's cognitive capacity.

Dr. Gold and her team started with a well-preserved skull from the National History Museum in London, which they imaged with high-resolution computer tomography (CT) scanning. They then used CT scanning to capture images of the skulls of seven species of pigeons plus the Dodo's closest relative, the Rodrigues Solitaire (Pezophaps solitaria), another extinct island-dwelling bird. From these scans, the team built virtual endocasts (casts of the braincase) to determine the overall brain size and the size of different brain structures in the different species.

Among their findings: the Dodo's brain was in about the same proportion to its body as a pigeon's. This means that the Dodo may have been about as bright as a pigeon. Since pigeons are smart enough to be trained, the implication is that Dodos may have possessed a moderate level of intelligence. Of course there's more to intelligence than brain size, but it's a good start.

One unexpected finding was that the olfactory bulb–the part of the Dodo's brain responsible for smell—seemed to be enlarged. This is unusual in birds, which typically have brains developed for keen eyesight. The Rodrigues Solitaire had a similarly enlarged olfactory bulb. Gold and her team suggest that, being flightless land-dwellers, Dodos and Solitaires may have depended on their sense of smell rather than their eyesight to hunt for food. 

One rather mysterious result: the research team discovered a strange curvature in the Dodo's semicircular canal—the balance organ in the ear. The team has yet to find a good hypothesis for this feature.

Want the whole story? Check out the team's findings in the Zoological Journal of the Linnean Society.

 

 

A Few Penguin Facts in Honor of World Penguin Day

April 25th was World Penguin Day. Why this date? We're not sure, but we think it's to commemorate the annual migration of Adelie penguins (Pygoscelis adeliae). Every April 25th, they dive into the Antarctic and swim a few hundred miles north (about 600 km) to where the ice is broken up so they can feed easily. They hang out there until spring (which is fall here in the Northern hemisphere).

There are 17 known penguin species, all of which live in the Southern hemisphere. The largest is the Emperor penguin (Aptenodytes forsteri) and the smallest is the Little Blue penguin (Eudyptula minor). Emperors can get to be about 4 feet tall (120 cm), while Little Blues stand only about 16 Inches tall (40 cm).

Most of us aren't aware that there are African penguins. The Blackfooted, or African, penguin (Spheniscus demersus) is native to South Africa, Namibia, and some offshore islands. 

Then there are the Yellow-Eyed penguins (Megadyptes antipodes), which live in New Zealand. Their chicks take 100 days to reach maturity. 

The Galapagos penguin (Spheniscus mendiculus) breeds right on the equator. 

The Chinstrap penguin (Pygoscelis antarctica) nests in enormous colonies. One colony in the South Sandwich (Antarctic) Islands consists of 10,000,000 penguins. 

The first egg in the best of a pair of Macaroni penguins (Eudyptes chrysolophus) is up to 64% smaller than the second egg. This first egg rarely hatches. 

Can't wait for next year's World Penguin Day? Well, January 20th is Penguin Awareness Day. We here at Talkin' Birds think we'll wear our tuxes.

 

 

 

 

 

Preventing Concussions: Learning from Woodpeckers

Why Don't Woodpeckers Get Headaches? is not only the title of Mike O'Connor's first book. It's also the driving question behind a new device that could help prevent concussions. Here's the problem: While helmets can prevent skull fractures, they can’t prevent concussions. The brain floats in fluid inside the skull and can therefore slosh around during impact. The solution? Consider the woodpecker. 

Dr. David Smith, CEO of Xennovate Medical, received a bit of advice from an attendee at one of his lectures in 2007. The advice was to investigate how woodpeckers manage to knock their heads against trees all day without suffering any ill effects. Smith appreciated the advice and began studying woodpeckers. 

A woodpecker has a very long tongue. In some species, the tongue is supported by bones that wrap all the way around the head. It appears that the tongue compresses the bones, and therefore the neck veins, as the woodpecker thrusts its head forward. The resulting slight increase in skull fluid volume helps keep the brain from knocking against the skull.

Smith wondered whether the same effect could be reproduced in humans, perhaps with some kind of collar. He contacted Dr. Julian Bailes—yes, the doctor played by Alec Baldwin in the 2015 movie Concussion. Bailes had testified before Congress in 2009 about head injuries in the NFL, having been team doctor for the Pittsburgh Steelers from 1988-98.

Smith and Bailes designed a collar that gently presses on the back and sides of the neck, leaving the throat unobstructed. The pressure slightly compresses the jugular vein, slowing the blood flow out of the brain. The result: the skull temporarily contains an extra teaspoon of blood. This extra teaspoon of volume, which causes no harm, reduces the amount of sloshing that the brain can do when the head is walloped.

Smith and Bailes tested their first model on rats. It worked well enough that they decided to move on to human subjects. Three years ago, Smith and Bailes invited Dr. Gregory Myer at the Human Performance Laboratory at Cincinnati Children’s Hospital to join their effort. They tested the collar with high school football players. The results will appear in a paper that Myer intends to submit for publication early next year.

Performance Sports Group, which makes Bauer ice hockey equipment and Cascade lacrosse helmets, has committed $7 million toward production of the band. More importantly, CEO Kevin Davis has such confidence in the band’s effectiveness that he’s asked his son to wear it when he plays hockey.

We hope he says "Thank you" to any woodpeckers he sees or hears on the way to practice. 

 

Flying Ghost Cat?

Next time you use Google, try searching on the phrase "the internet names animals." You'll get a photo of a zebra labelled "PRISON PONY," a rhinoceros labelled "LEATHER TANK," and a crocodile labelled "AMERICAN MURDER LOG," among other gags. These silly animal names are an internet meme--that is, they're popular and spreading rapidly. We here at Talkin' Birds like to stay ahead of the trends (you know how fashionable we are!), so we thought we'd start a meme titled "the internet names birds." We don't want you left behind, so contribute your own! In fact, if you've got an idea and you don't have a chance to make it yourself, tell us about it and we'll try to post it for you on our Facebook page.

Here are some starters....

Snowy Owl

Snowy Owl

Brown Pelican

Brown Pelican

Broad-Billed Hummingbird

Broad-Billed Hummingbird

Now it's your turn!

 

Sharp-witted Birds of the Antarctic

Crows, magpies, and mockingbirds have been known to recognize individual people. These birds live among people, though, so it makes sense that they would develop this ability. Scientists in South Korea have recently reported that the Brown Skuas of Antarctica can recognize people, too, but they hardly ever see us. The journal Animal Cognition details the findings. 

Researchers who accessed skua nests to measure eggs and nestlings noticed that parent birds seemed to target them for attack when they visited repeatedly. "I had to defend myself against the skuas' attack," says Yeong-Deok Han, a PhD student at Inha University. "When I was with other researchers, the birds flew over me and tried to hit me. Even when I changed my field clothes, they followed me."

The research team performed a series of experiments to make sure the birds were indeed recognizing people. First, the researchers checked the nests once a week to monitor breeding and to accustom the skuas to being visited. The skuas responded by attacking at greater distances with repeated visits, indicating that they recognized intrusions more quickly. Next, to test whether the birds could distinguish researchers who'd visited the nests from those who had not, a pair of people consisting of one intruder (who had accessed the nests) and one neutral visitor (who had never accessed the nests) approached the nests and walked away in opposite directions. All seven skua pairs followed and tried to attack the intruder but never the neutral visitor.

Study leader Dr. Won Young Lee, a Senior Researcher from Korea Polar Research, is impressed by their cognitive ability. Dr. Lee states, "Since this area has been inhabited by humans only after the Antarctic research stations were installed, we think that the skuas could acquire the discriminatory abilities during a short-term period of living near humans."

The cognitive abilities of Antarctic animals have not been well studied. Brown Skuas have been known to steal food from other birds and even the breast milk of nursing elephant seals. According to the researchers, these opportunistic feeding habits might help keep their wits sharp.

Want to see how Brown Skuas react to nest intruders? Check out this video:
https://youtu.be/5INsdKej0ow

Nest-Building Lessons

Most birds build nests, but how do they know how to build them? It's not like there are published blueprints. Very little research has been done on how nest-building birds know what they know, but here's an intriguing study. 

Male Zebra Finches build circular, domed nests for their mates and chicks. New research at the University of St Andrews, Scotland, shows that Zebra Finch males learn to build these nests at least partly by watching other Zebra Finch males. However, they'll imitate only the males they know. 

Scientists in the School of Biology paired up female Zebra Finches with males who had never built a nest. Each pair watched the male of another pair build a nest; this male was either known to them or a stranger. While building, this male used pink or orange string, colors that Zebra Finches don't normally use. (How they got him to use those colors isn't explained. Our guess is they had him read a 1970's issue of Architectural Digest.)

When the time came for the newbie nest-builder to build his first nest, he used the same color string as the male who demonstrated--but only if the demonstrator was a familiar bird. If the demonstrator wasn't, then the newbie did not make the same color choice. 

The experiment showed that birds will turn to public information when they need to decide which materials to use to build their first nest, but only if they know the individual who provided the information. We think birds could teach human students a thing or two about doing research for school papers with Google. 

Dr Lauren Guillette of the School of Biology, lead of this study, suggests that birds might learn from one another in a way that resembles human beings' learning culture.  "This is called ‘social learning’, and can save time and effort for first-time nest-builders....Perhaps surprisingly, the birds did not always use this ‘advice’, especially if it came from a stranger. In humans, learning from those we know is one way that cultural traditions are formed, from the tools we use to the clothes we wear or the music we listen to.”

Want to read the original article? Find it here. 

Now Starring: No American Birds

When we birders watch films and TV shows made in America, we often say, "Wha-?" We notice that the birds onscreen in a show supposed to take place here are actually foreign birds. No, it's not because of Hollywood sloppiness. It's because of the law. 

The Washington Post explains: The federal Migratory Bird Treaty Act (MBTA) of 1918 prohibits the possession of migratory birds for commercial purposes. This means it's illegal to keep domestic bird species as animal actors. Why? Steve Holmer, a senior policy advisor at the American Bird Conservancy, says that, before the MBTA, populations of some birds were severely harmed because they were used so often commercially. Snowy egrets, for example were decimated in the early 1900s because their plumes were used to decorate hats.

Are you surprised that native birds can't be used as actors? So were we, and so are many producers. Benay Karp, owner of Benay’s Bird and Animal Rentals in Woodland Hills, California, says producers often come to her looking to rent a native bird and leave with one that looks similar but actually isn't the genuine article. 

The good news is that egret numbers have rebounded, along with those of many other species. The Migratory Bird Treaty Act has been a success, and Hollywood is still abiding by it. 

The bad news is that birds are being used in film and television that aren't native to the United States. Not only is it expensive to import a non-native bird, but it also can't be pleasant for the bird. We here at Talkin' Birds are rather conservation-minded; we don't want birds from anywhere to be harmed. 

Now, how about when we hear the wrong bird in a film or TV show? Is that also because of the MBTA?

No. That really is because of Hollywood sloppiness. 

 

Ray on NPR Discussing Weird Bird Behavior

One of the things we love about birds is that they demonstrate an immense variety of survival strategies. Since they live all over the world, in all kinds of conditions, they have had to develop ways to cope. Recently, Ray spoke with NPR's Lourdes Garcia-Navarro about some of the more bizarre behaviors observed in birds. Listen here for this brief, fun interview. 

Scrambling Eggs' Incubating Temperatures

New research indicates that climate change may affect the development of embryos in birds' eggs, especially if the birds live in a hot climate.

A team of scientists at Australia's Macquarie University studied the effects of warming atmospheric temperatures on in-the-egg development of wild Zebra Finches, Taeniopygia guttata (yes, we're discussing Zebra Finches again).    In the wild, the Zebra Finch breeds in arid and semi-arid regions throughout Australia where atmospheric temperatures regularly exceed 96.8◦F. Like all birds, Zebra Finches can lay only one egg per day. They don't start incubating them until the clutch is complete, which takes about five days.

All the eggs are incubated equally, and they tend to hatch on the same day. Why does this matter? Because the chicks who hatch first grow big first, depriving their smaller siblings of resources. 

The Australian research team suspected that warm temperatures might cause problems during the egg-laying, pre-incubation stage. If the ambient temperature were to become warm enough for eggs to develop even without an adult sitting on them, the earliest-laid eggs would hatch earliest.  They were also concerned that Zebra Finches might be reaching the upper edge of their tolerance for high temperatures--in other words, that heated eggs might not hatch at all.

To test the prediction that warmer nest temperatures trigger early development, the team set up “hot” and “cool” experimental nest chambers. Thirty-three eggs from eight clutches were removed from their parents' nests on the day they were laid and placed into one of the four chambers. They were kept cool or warm while their sibling eggs were laid, then returned to their parents, who incubated the entire clutch until hatching. 

All the experimentally treated eggs hatched following their return to the parental nest, no matter how they had been treated--that's the good news: even the "hot" eggs survived. Overall, the average developmental time was 13 days — shorter for eggs that had been placed in the “hot” nest chambers. Also, as predicted, the eggs laid early in the laying sequence developed and hatched sooner.

Now the bad news: the time to hatching was similar for eggs placed in either the natural nest chambers or in the nest-box nest chambers--just 13 days, when 14 days had been expected. In other words, even though the heat-treated eggs hatched first, ALL the nests were "hot" enough to hatch fast.

What does this mean? That the nests of birds in hot climates are already affected by climate change, and they might suffer more if temperatures increase.

How Zebra Finches Choose their Valentines

Like many birds, Zebra Finches tend to pair up and stay paired. However, how they choose their mates is a bit of a mystery. 

Whereas many animals choose their mates for certain physical traits, Zebra Finches don't seem to do so. Malika Ihle and her colleagues at the Max Planck Institute for Ornithology, in Seewiesen, Germany recently published their research into what makes Zebra Finches pair up. 

The studied 160 single Zebra Finches, allowing groups of 20 males and 20 females in an aviary to become acquainted with one another. Grooming is a sign of Zebra Finch courtship, so when pairs started grooming each other, the researchers knew that those birds were capable of pairing. They let half the couples stay together. The other half they divided into "arranged marriages." They caged all the pairs for a few months so they could develop relationships, then released them into a group aviary to raise their families. 

Over the following five months, the researchers observed as the pairs went through three breeding cycles. Then they repeated the experiment, this time allowing only one third of the birds to stay with their mates. 

The results? Couples who had chosen each other had 37% more surviving young than those who had not. Forced couples produced more unfertilized eggs, lost more eggs, and had more chicks die after hatching. Females in forced pairs were not as interested in mating as those who had chosen mates. Males in forced pairs were less interested in caring for chicks and more interested in mating with other females. 

Dr Ihle and her colleagues say that, if the finches were choosing mates for genetic reasons, more embryos would have died from defects caused by interbreeding between such a limited selection of partners. However, the difference in the survival of chicks appeared to depend on how well they were cared for by their parents. The researchers argue that the results they saw indicate that Zebra Finches select their mates based on how well they get along. We here at Talkin' Birds don't think that's a bad way to choose. 

 

 

Common Poorwill, Uncommon Habit

It hibernates. 

We can already hear you: "Say what? The Common Poorwill hibernates? You have GOT to be kidding. Birds don't hibernate!" 

We're not kidding. Named "The Sleeping One" by the Native American Hopi tribe, the Common Poorwill (Phalaenoptilus nuttali) has a tendency to lie around all winter. This small, black and gray nightjar spends the colder months concealed in piles of rocks. It's not completely asleep, like, say a bear; instead, it's very greatly slowed down--a state called "torpor," in which metabolism and body temperature are reduced for days or even weeks. While some hummingbirds experience daily, short-term torpor in order to conserve energy, the Common Poorwill is the only bird known to have long bouts of it, which some scientists call hibernation. 

The Common Poorwill is nocturnal, which is rare in itself. Its habitat ranges from British Columbia and southeastern Alberta down to northern Mexico via the western United States. It prefers dry, open areas with grasses or shrubs; it also likes sparsely vegetated, stony desert areas. It is in the southernmost part of its range that the poor-will has most often been seen its long torpor bouts, usually in extremely cold and extremely hot weather, and sometimes even while incubating eggs. 

The Lewis & Clark expedition found torpid (or hibernating) Common Poorwills in North Dakota back in 1804. Dr. Edmund Yaeger described them in California in 1948.

In torpor, the poor-will's body temperature as been measured as low as 40°F, with a respiration rate reduced by 90%. That's pretty cool, huh? (In more ways than one.)  

 

We're Not the Only Junk Food Addicts

As we tuck into our Superbowl snacks this weekend, let's be grateful we're not seabirds. In fact, please chew whatever you have in your mouth before you read further.

Ready?

For some seabirds, fishing waste is a blessing. Fish parts and other refuse discarded by fishing boats help certain birds sustain much larger populations than could otherwise survive in their area. Gulls usually benefit near shore, and albatrosses, skuas, petrels, and frigatebirds will follow commercial fishing vessels to scavenge easy snacks. However, this stuff is actually a mixed blessing for the Cape Gannet...rather like nachos are for us.

Cape Gannets breed on islands off the western coast of South Africa and Namibia. The waters are a prime location for small fish such as sardines and anchovies and the larger fish that prey upon them. Fleets of commercial fishing vessels have joined the flocks of gannets to reap the bounty, and adult gannets have learned to follow fishing boats to feed on discarded fish parts. Often, the fish would have been too large for the gannets to capture themselves, which means the gannets have access to food they otherwise wouldn't. (Think of your neighbor's seven-layer bean dip, which you can never make because you're always missing an ingredient.) In fact, sometimes fishing waste makes up more than 80 percent of the diet of adult gannets, contributing to their very high survival rate. Burp.

High survival rate? "So what's the problem?" you ask. The answer: feeding the kids. Fishing waste is a good food resource for adult gannets, but it is much lower in calories than the small, oily fish that their babies should be eating. Gannet chicks don't grow well when they eat mostly fishing waste. In fact, their parents seem to know this: parents with chicks make many more dives seeking live fish than do non-breeding adult gannets. Unfortunately, depletion of the anchovy and sardine stocks by overfishing has made it harder for Cape Gannets to find the food their young need to thrive. They often have to feed their babies on fishing waste because there's not enough of anything else. Sadly, in some years nearly all of the chicks in such colonies have died. Researchers refer to this problem as the “junk-food” phenomenon. 

Want to find out more after the game? Read this: Gremillet et al. A junk-food hypothesis for gannets feeding on fishery discards. Proceedings of the Royal Society of London B 275:1149-1156 (2008). Thanks to The Cornell Lab of Ornithology for reporting on this research. 

Female Songbirds: Quiet for Good Reason

Female birds are capable of song in 71% of songbird species, So how come we don't hear them as often as we hear the males? New research indicates that sometimes female songbirds have good reasons to stay quiet. 

Sonia Kleindorfer, a behavioral ecologist at Flinders University in Adelaide, Australia, studied the singing patterns of female and male Superb Fairywrens (Malarus cyaneus), a small Australian songbird species. Like the females of many species, female Superb Fairywrens often sing for territorial defense, sometimes even when they're on their nests. They use a melody known as a "chatter song." The male uses it too, but he is not as often near the nest when he sings.  This is a key difference, since singing alerts predators such as rodents, cats, and foxes. Kleindorfer investigated whether male singing or female singing poses a greater risk.

During the nesting seasons of 2013 and 2014, Kleindorfer and her colleagues monitored male and female singing on and near 72 wild Superb Fairywren nests, as well as the eggs and chicks in the nests. The scientists counted a nest as “attacked” if eggs or chicks vanished in under 25 days. In other words, if eggs disappeared unhatched or chicks disappeared before they were capable of fledging, researchers assumed they'd been eaten. 

Kleindorfer's team leaned that both males and females sang the chatter song more often when they were just beginning to nest. They sang it less often when they had eggs and chicks in the nest, and with one major gender difference: The males sang away from the nest and the females near or inside it. In fact, some females never sang at all, and some sang only in response to their noisy mates. To put it differently, the females sang less when doing so would endanger their nests. Proof? The scientists baited artificial nests with quail eggs and broadcast female chatter songs infrequently (six calls per hour) and frequently (20 calls per hour). Predators ate the eggs at 40% of the "frequent" nests, but at only 20% of the "infrequent" nests: the quieter nests were safer for the kids. 

Jordan Price, a behavioral ecologist at St. Mary’s College of Maryland, posits that danger to the nest could be the reason that female songbirds of other species sing far less than their partners—or not at all—when they're the primary on-nest parents. It's even possible that, generally, male songbirds sing not to attract mates but simply because there's no reason for them not to. The females, on the other hand, have to be more wary. 

Vote for Entries in Cornell Lab's Bird Coloring Book

These days, it's cool to relieve stress with coloring, like you did when you were a kid. And birders know that spending time with wildlife also helps to relive stress. So combine coloring with birds and you get the Cornell Lab of Ornithology Bird Academy's new coloring book.

The book is being developed now, and you can help. Go to their coloring book project page and vote for the species you'd like to see.  The top 15 species will be featured in the book. As a bonus, you can sign up for a drawing to receive a free copy of the completed book. Your email address gets you a free coloring page to download right now. 

If you'll excuse us, we're going to go get our crayons.

The Nocturnal Kiwi Bird

Instead of shivering while we think about winter, let's contemplate a bird who lives where it's summer right now: New Zealand's kiwi bird.  

There are five species of kiwi, all of them endangered, all of them flightless. They have no tail, only rudimentary wings, and nostrils at the end of their long, slender bills. As if those traits aren't weird enough, they are also nocturnal. We here at Talkin' Birds wonder whether they ever star in New Zealanders' ghost stories, but never mind.

Kiwis emerge from caves in the evenings to forage for food. Perhaps because they're active at night, they have lost their color vision and have gained an acute sense of smell. Interestingly, they also have a lower body temperature and slower metabolism than other birds. 

Fewer than 3% of the world's bird species are nocturnal. Researchers from the University of Leipzig and Max Planck Institute for Evolutionary Anthropology estimate that the kiwi became nocturnal about 35 million years ago, after its ancestors came to New Zealand. Why? They're not sure, but perhaps other bird species crowded them out of daytime food resources and they had to adapt. These researchers have sequenced the kiwi genome for the first time ever. Their findings recently appeared in Genome Biology, so take a look.

Too-Dark and Too-Light Birds

We can rely on our field guides, right? All birds of the same species and gender look the same?

Wrong. When it comes to color, an occasional bird may be darker or lighter than the others of its species. That's when you find yourself looking back and forth between the bird and your field guide and saying, "It SOUNDS like that one and it ACTS like that one and it's in a whole FLOCK of them--but it's the wrong color!" 

So what's going on?

If a bird is darker than usual: It's "melanistic" or a "dark morph." These birds possesses an excess of dark pigment, called melanin, in their feathers. They are sometimes so dark that their markings are impossible to see. Therefore, it's best to identify them by sound, behavior, and association with other birds. Some species, such as red-tailed hawks and ferruginous hawks, have regularly occurring instances of such birds. These more common dark birds are known as dark morphs.

Melanistic and dark morphed birds have a couple of advantages over normally colored birds. First, their dark feathers absorb sunlight more easily in cold climates, helping them stay warmer than normal birds. Second, darker birds generally have an easier time with camouflage. The disadvantage of excess melanin? It makes feathers brittle, so they break easily.

if a bird is lighter than usual: It's albino or "leucistic." These birds lack dark pigmentation.

Albino birds—very rare—are unable to produce melanin at all. They may have red markings only (red pigment is unaffected) or they may look completely pale, and their eyes appear pink or red. Since their eyes have no protection from UV light, they don't see very well. Their poor eyesight and light coloring make it unlikely that they'll survive until adulthood. 

Leucistic birds might lack either of two kinds of melanin, or their bodies simply might not be able to deposit melanin in their feathers. They appear lighter than others of their species, making them easier for predators to see. Their feathers tend to wear out quickly. 

So next time you see a bird that looks darker or lighter than the picture in your field guide, remember that it might be one of these variants. And let us know!

 

A Scandinavian Christmas Tradition for the Birds

Birds don't celebrate Christmas, but they appreciate a feast at any time of year. Begun perhaps to distract birds from grain stores, the Swedish tradition of sharing the final harvest is a charming way to end the old year and welcome the new. 

The Julkarve, or Christmas sheaf, is customarily a farmer's last sheaf of harvested grain. The household bundles it together and places it high on a pole or rooftop on Christmas Eve, inviting local wild birds to dine. Legend says that a good crop next year is foretold if many birds gather. 

Want to try this? Check this article for an easy how-to. 

Don't have a pole or rooftop? Try spreading seed on the ground, a doorstep, or the top of a fence. Just make sure to tell the birds to stay clear of any reindeer. 

Merry Christmas Bird Count

Back in the 19th century, what we now know as the Christmas Bird Count (CBC) was the Christmas Side Hunt. The winning hunter would be the one who brought back the most prey. So how did this hunt get to be a bird census? More importantly, how do you tell who wins?

Back then, Americans were much more interested in hunting than in conservation. However, even the most driven hunters were beginning to notice that certain bird species were in decline. In 1900, the ornithologist Frank M. Chapman (officer of the very young Audubon Society) proposed a Christmas Bird Census instead of the traditional Christmas Side Hunt. That year, twenty-seven birders all over North America counted 18,500 birds in 89 species. A new Christmas tradition had begun.

So who wins the Christmas Bird Count? You guessed it: everybody, especially the birds. CBC data, gathered by citizen scientists for over a hundred years, provides an indispensable long view of the health and distribution of bird populations all over North America. 

Want to learn more, see the data archives, maybe get involved yourself? Signups begin every November, and the single-day counts take place starting a couple of weeks before Christmas. Check out the Christmas Bird Count on the Audubon website here