Wednesday, March 31, 2010

Whooping Cranes to Get GPS Units

Over the next three years, Whooping Cranes in the western migratory flock are going to be fitted with GPS tracking devices that broadcast a crane's location every six hours.
They have permission to trap and band 10 whooping cranes in the winter and 10 in the summer for three years. It's a big job, and potentially dangerous for all concerned. Trapped birds can develop a potentially fatal muscle ailment called capture myopathy. Bird-banders can get pecked or scratched.

The birds are caught with a rope snare that lies on the ground and is attached to a bent fishing rod. When a walking crane trips it, the rod recoils and tightens the leg noose in a way designed not to traumatize the bird. Two whoopers were outfitted with GPS anklets last winter. Start to finish, the procedure took 15 minutes for one and 16 minutes for the other.

Each device costs $4,500, and the tracking service, provided by a private company, costs $1,500 a year. The anklets are solar-powered and designed to last at least three years. In a trial run the researchers last spring put devices on two sandhill cranes; they're still working.
The program was developed partly to avoid situations like the particularly bad winter that the flock suffered in 2008-2009, when 57 of the cranes died. The location data gathered by the GPS units will provide more detailed information about cranes' migration routes and favored habitats.
"We hope to learn something about their habitat-use patterns," Chavez-Ramirez said. "Where do they spend the night? What are the characteristics of those sites, the depth of the water, the vegetation? We've never had a quantifiable way to evaluate where they roost."

Wetlands are being lost throughout the birds' migration route, he said. The tracking program "will let us understand what they want and what they use so that perhaps we can reproduce those conditions."

It may also help answer more speculative questions.

As part of her research, Gil has correlated climatic variables with the whooping crane population size and the reproductive success of birds identified by colored leg bands (including one four-generation lineage). She has found that the population declines in rough synchrony with the Pacific Decadal Oscillation, a pattern of Pacific climate variability similar to El Niño. This decline is probably due to weather extremes during those years: low temperatures, which stress the birds, and a shortage of rain, which lowers water levels and exposes their nests to predation.
This point is not mentioned in the Post article, but I hope that the data gained from the study can help the eastern flock in some way as well.

Tuesday, March 30, 2010

Eagles Eating Great Blue Herons

Occasionally someone will ask me if a particular large species, like a large raptor or heron, has any predators. While I know some general rules about predation, I cannot always provide specific examples that I have witnessed. Most large birds are vulnerable to attack under the right circumstances, especially if they are already injured or caught by surprise. All birds are particularly vulnerable when they are young.

Here is one example of what might eat a heron. In Washington state, Bald Eagles are eating Great Blue Herons in the nest.
Near a small pond on Renton's western edge, nests of great blue herons, perched up to 100 feet high in a stand of cottonwood trees, appear safe from any danger from below.

But not from above. ...

Particularly during the breeding season, now under way, heron watchers report seeing eagles chasing herons off their nests, then preying on the eggs and hatchlings left behind.

"They'll eat the young right there on the nest, or carry one off," said Pam Cahn, a volunteer with Heron Habitat Helpers, which monitors and helps maintain a nesting ground in Seattle's Kiwanis Ravine near Discovery Park.

Eagles also will sometimes attack an adult heron. O'Keefe saw an eagle with an adult heron in its talons near his Vashon Island home. "The eagle took it down to the ground and finished it off," he said.
At one location, eagles started nesting near a heron colony after the eagles' original nesting site was cleared for development. After that, the number of young herons fledged from the nests dropped from 360 in 2004 to less than 50 last year. However, it is not clear how much eagle predation is hurting the heron population as a whole. Great Blue Herons are declining in the Pacific Northwest, but other causes could be a factor as well. 

Monday, March 29, 2010

Harsh Winter Changes the U.K.'s Bird Population

Fieldfare / Photo by Matt HB

This year Western Europe had one of its coldest winters in recent memory. As one might expect, this changed bird distribution. The numbers are in from the RSPB's Big Garden Birdwatch, and many species are down compared to last year's results. The Guardian has a summary of the changes.
The survey saw 530,000 people take part and their records showed the average number of birds per garden for already rare goldcrests were down 75% on January 2009, being seen in only about 5,300 gardens. Long-tailed tits were down 27% to an average of one bird per garden, and coal tits down 20%. The long-tailed tithad been thriving due to a succession of mild winters and was one of last year's big success stories.

This winter's bitter weather had a greater impact because the cold spell was national Kelly explained. Most previous drops in small bird populations caused by cold weather - such as the death of all the Cetti's warblers in Kent after two successive cold winters in the mid-1980s - were only regional.
It is not clear from the article what happened to these missing birds. The cold may have pushed them elsewhere, perhaps further south in Europe. They could also have died of cold-related causes, whether hypothermia or starvation. Or perhaps a bit of both. If this count is based solely in the U.K., it would not be possible to answer the question from this count's data alone. (This is one advantage of the Great Backyard Bird Count – it is easier to see movements over a continent-wide scale.) Relocation seems more likely, in my opinion, since the Big Garden Birdwatch showed evidence of a different set of species moving into people's gardens:
The snowy winter also led to a huge rise in sightings of countryside birds such as thrushes and finches in the UK's gardens. The number of fieldfares was up 73% on last year, redwings up 185% and song thrushes up 51%, though their numbers are still relatively low compared to garden stalwarts such as blue tits and chaffinches....

Another species apparently doing well was the blackcap, which was up 47% against 2009 levels. The RSPB believes many may have been migrants sheltering from even harsher weather in mainland Europe, though it also speculates that the increased sightings may simply be a result of the blackcaps getting used to eating from bird feeders and becoming more visible.
If you would like to look at the data yourself, it is available online, including in a Google spreadsheet.

Sunday, March 28, 2010

Review: Peterson Field Guide to Birds, Revised Editions

North American birders are fortunate in being able to choose among multiple field guides. Ever since bird study shifted from guns to binoculars, Roger Tory Peterson's bird illustrations have helped birdwatchers identify birds. Though Peterson died almost fourteen years ago, his guides live on after his death and continue to assist birders today. This spring the publisher is releasing new revised versions of Peterson's two regional guides to match the single-volume Peterson guide from two years ago: a Peterson Field Guide to Birds of Eastern and Central North America and a Peterson Field Guide to Birds of Western North America. The eastern guide is now in its sixth edition, and the western guide is in its fourth edition.

The new eastern and western guides have attractive covers featuring Peterson's artwork, similar to the 2008 Peterson and unlike the style used for Peterson guides covering other taxa. The eastern guide has a Northern Mockingbird; the western guide has a pair of American Kestrels. The books' front and back matter feature several photographs taken by Jeffrey Gordon. (He recently devoted a series of blog posts to the photographs used for the Peterson guides. It is worth checking out his posts, even if you are not interested in these field guides.) The western guide is about 50 pages longer; both guides are small enough for a jacket pocket but too large for a pants pocket. The books have associated video podcasts, available online.

The revised guides use Roger Tory Peterson's classic bird illustrations, the same as have been used in past editions of the Peterson bird guides. However, the colors appear fresher and the bird illustrations are reproduced at a larger size compared to my fourth edition of the eastern guide. Another change that I noticed compared to my older edition, is the addition of short sections on how to identify shorebirds by shape and how to age gulls. While these sections are not as good as the ones in Birds of Europe, they should help less experienced birders with those difficult groups.

Taxonomy has been updated to reflect classification and name changes through the 50th Supplement to the AOU Checklist in 2009. Because of recent taxonomic splits and observations of new species for the ABA area, Michael O'Brien painted new illustrations for the revised edition. The new illustrations follow Peterson's simplified style but have subtle differences. On O'Brien's paintings, such as the illustration for Cackling Goose, the individual brush strokes are not as noticeable as on Peterson's.

Opposite each plate of illustrations is a page with short accounts for each of the species depicted. Each species accounts contains the English and scientific names, dimensions, and notes on identification, voice, similar species, and habitat. The species accounts are written in Peterson's telegraphic style, in many cases with his exact words. However, they have been updated with additional information, especially if new identification methods have been developed by field birders.

Range maps accompany the species accounts on the pages opposite the plates. They also appear in larger form in an appendix. Range maps in the appendix include explanatory notes for each map, while the maps beside the species accounts do not. Though the range notes provide some useful information, I generally rely on the map opposite the plate when I am in the field and rarely check the map in the appendix. If other readers do the same thing, the range map appendix may just add bulk to the book. In my opinion, these maps did not need to be printed twice, and the appendix could be excised to make the book lighter and smaller for field use.

Even though over 70 years have passed since the eastern guide's first edition, the Peterson bird guides remain a worthy choice for North American birders. Whether you want to use this guide will depend on your own needs and tastes. The simplicity of Peterson's approach and clear explanations of field marks makes these excellent guides for beginners.  However, intermediate and experienced birders will likely prefer more advanced guides since the Peterson guides' plates lack many plumages.

Saturday, March 27, 2010

Songbirds, Berries, and Anti-oxidants

Researchers believe that migratory songbirds at Block Island choose to eat arrow-wood berries specifically for their anti-oxidant content. The berries might relieve some of the physical stress that songbirds endure during long-distance migration flights. Arrow-wood berries contain higher levels of anti-oxidants than many of the other berries present on the island at the same time.

"When I started studying birds during their migratory stopover on Block Island, I was impressed that most of the migratory birds ate berry fruits even though they usually eat insects or seeds at other times of the year," said McWilliams, who came to URI in 1999. "I began studying the relationship between the nutritional qualities of fruits and how those nutrients might fuel migration." ...

The research indicates that birds prefer to eat certain fruits that have more antioxidants and key nutrients. In return, the seeds in the berries are dispersed by the birds. "It's the way plants ensure their survival. Birds eat the berries, digest them and defecate the seeds over wide areas," McWilliams said.

"Meanwhile, the birds are attracted to the berries because of their rich color, which we believe is a plant's response to the stress of constant exposure to the sun and other stresses. Berry color could be a plant's way of fighting oxidative stress. It's a partnership that benefits plant and bird."

The Seeram-McWilliams partnership will continue. "We've only measured a few of these anti-oxidants," Seeram said. "Our next step is to determine how birds can detect these compounds."

"Whenever we exercise, we undergo oxidative stress, and the same is true for birds," McWilliams said. "We're flying birds in wind tunnels to produce oxidative stress, and then we are going to see if anti-oxidants found in these berries alleviate that stress," McWilliams said.

The research may benefit human health as well as bird conservation. If further research shows the direct link between bird health and diet, then the findings will play a critical role in habitat protection for migratory birds, McWilliams said.
This is interesting, if true. I wonder how much of the preference could be explained simply by availability, size, or taste. I also wonder whether this would really mean much for humans. Anti-oxidants already receive quite a lot of publicity for their ability to treat or prevent various ailments. I am not sure that adding one more would change food consumption habits.

Friday, March 26, 2010

Loose Feathers #231

Dark-eyed Junco / Photo by Dave Menke (USFWS)

Birds and birding news
  • Paleontologists found a fossil of a new bird species, Longicrusavis houi, which lived in the early Cretaceous. Its long shins suggest that it may have been a wading bird.
  • Researchers found that the preen oils of two populations of Dark-eyed Juncos produce different smells. Males and females of each population also produced different smells. Since the birds were captive-raised, the differences appear to be genetic rather than environmental, which suggests that smell could play a role in species differentiation.
  • Male Great-tailed Grackles have glossier feathers than females, and the glossiest males are the most  attractive. The glossiest males also tended to have the longest tails, another sexually-selected trait.
  • Three new breeding sites for the extremely rare Worthen's Sparrow have been found in northeastern Mexico. This sparrow's population is estimated to be just over 100 individuals in the wild.
  • An amateur paleontologist found fossil bones of a new bird species, Flexomornis howei, in Texas. The bird lived about 96 million years ago.
  • The US government is spending $2 million to restore bird habitat at Mauna Loa. Even though Hawaii accounts for 44% of endangered bird species in the US, it usually receives only 4% of state and federal conservation funding.
  • The American Bird Conservancy has published a downloadable brochure on ways to prevent birds from hitting windows. Window strikes account for 300 million to 1 billion bird deaths per year.
  • Bird bones are hollow, but the bone material is denser, so that a bird skeleton will weigh the same as the skeleton of a mammal of similar size.
  • Two communities in Bolivia have designated about 500,000 acres as a conservation area to protect the Red-fronted Macaw.
  • Five men (including four Navy officers) face federal charges for killing 21 protected waterbirds in Florida.
  • Over 150 birds were killed in an accidental fire at Gilcrease Nature Sanctuary in Nevada.
  • Philadelphia is turning a formerly wooded section of Fairmount Park near the Wissahickon Valley into a butterfly meadow to match its historical character. The change is expected to benefit some bird species as well.
  • The UK's oldest Osprey, estimated to be 25 years old, returned to its nest again this year. This female has laid 55 eggs, 46 of which have been successfully fledged.
  • Plans to reintroduce Sea Eagles to England are running into local opposition, based partly on the fear that the eagles will prey on domesticated animals.
Birds in the blogosphere
Environment and biodiversity
  • Scientists have found the first truly amphibious insects: the caterpillars of Hyposmocoma moths. These are also the first caterpillars known to eat snails and other mollusks.
  • The EPA has proposed a rule to make the petroleum and natural gas industry and plants that inject carbon dioxide into the ground to report their annual greenhouse gas emissions, including methane and fluorinated gases.
  • A disputed island in the Bay of Bengal has disappeared is now covered by water because of rising sea levels.
  • The world's strongest insect is a dung beetle, Onthophagus taurus, which can pull objects up to 1,141 times its own weight.
  • Global deforestation rates have slowed since the 1990s but remain high. Global forest loss during the 2000s was about 13 million per year, as opposed to 16 million hectares per year in the 1990s. Africa and South America continue to lose forest cover, while other areas have held steady.

Thursday, March 25, 2010

Striped Squill

Striped Squill, a cultivated flower of early spring. The plants reach only about 6 inches in height and the flowers are very small.

Arctic Seabirds

Predicting how climate change might affect animal species is a major concern for conservationists. The best current summary of how climate change might affect American birds is the recently-released State of the Birds, but research is still ongoing. A recent study looked at how Arctic-nesting seabirds might be affected by studying ways that birds currently die at the breeding colonies.

Mallory and two other Canadian scientists decided to combine 33 years of observation into a paper that was released in Arctic, the journal of the Arctic Institute of North America. In it, the trio track the unusual ways Arctic seabirds die and they predict that a warming climate could have serious consequences for these birds. The study is based on observations of six species of birds on 11 different seabird colonies in the eastern Arctic ranging from northern Hudson Bay to Devon Island.

Typical causes of death include crashing into each other or cliffs during heavy fog, being slammed into the ocean by Katabatic winds or, perhaps most grizzly of all, dying from a combination of heat stress and blood loss due to mosquito attacks....

Few birds winter in the Arctic because of the harsh climate conditions. But in the spring, there is a veritable explosion as millions of birds return to nest. Seabirds in Mallory's study area tend to spend the winter months floating in the North Atlantic ocean. When they return in the spring, conditions are often still very harsh. Mallory has seen fulmars and thick-billed murres incubate eggs with only their heads visible above the snow.

The preferred nesting sites of many seabirds are cliffs, which often prove to be very dangerous. Falling rocks and chunks of ice, as well as slides kill great numbers of birds. In fact, the authors cite one incident in which over 800 murres and kittiwakes died almost instantly when the ledges on which they were nesting collapsed. Mallory suspects cliffs could become unstable as temperatures rise, with more freeze-thaw action of ice.
They also predict that increased storm activity could cause additional mortality among nestlings. Dampened feathers do not insulate very well, even in slightly warmer temperatures.

The press release and abstract do not specify which species were involved, beyond the Northern Fulmar, Black-legged Kittiwake, and Thick-billed Murre mentioned in the quote above.

Wednesday, March 24, 2010

More Crocuses

I am posting a few more crocus photographs in the short time that they are still blooming.

 The last two photographs show the same flower.

Tuesday, March 23, 2010

Two Moths

I saw my first moth of 2010 on the evening of New Year's Day – a tiny micromoth I disturbed when I picked up a towel. Despite its small size (about 6 mm), its wings have an intricate pattern of dark and light browns. That such patterns can appear on an otherwise nondescript insect is one reason I find moths so fascinating. I still do not know this creature's identity, though it bears some resemblance to the Webbing Clothes Moth.

I saw my first outdoors moth of the year when I was at the Great Swamp on Saturday. This is another micromoth, no larger than 10 mm. Once again I am not sure of the moth's identity; my best guess is that it may be a Fruit-Tree Leafroller Moth. As with the previous moth, this moth's wing pattern is more intricate at close range than it appears at a distance.

Micromoths are a difficult group, with many species, so these will probably stay unidentified for a while.

Monday, March 22, 2010

A Change of (Recovery) Plans for Whooping Cranes?

A major goal of the Whooping Crane recovery plan has been the establishment of a self-sustaining migratory eastern flock. At one point, wild Whooping Cranes had been reduced to a single population, the one that now winters in Aransas NWR. That situation would leave the species vulnerable to a natural disaster, epidemic, or other event that could decimate the flock and push it towards extinction, so a second flock is necessary for the long-term good of the species. Creating that second flock from captive-bred birds has proven difficult and expensive. The latest setback is that the proxy summer grounds may need to be moved from Necedah NWR in Wisconsin. Multiple crane pairs have been abandoning their nests, most likely due to swarms of black flies.
Clemency said the chief culprit appears to be marauding black flies - specifically, a species of the insect attracted to birds, not humans.

Research in 2009 by scientists from Clemson University revealed that black flies tend to congregate where the cranes nest. Traps caught few of the flies elsewhere on the refuge, "but thousands of black flies were observed at whooping cranes' nests," after the birds gave up and left, Clemency said.

The researchers found that the flies travel as far as five or six miles to be near the cranes. Why? It's not clear, but Clemency said possible attractions are the birds' feces or hormonal secretions. Scientists don't see black flies hassling cranes in Canada.

This spring, the partnership will experiment with using a naturally occurring soil bacterium to control the flies in the Yellow River.

Also, for the first time researchers will be training high-resolution cameras on nests to see what happens next month, when cranes in past years have left their nests.

"This will give us details not only of the birds in the nest, but we'll be able to see how many flies are on the heads of the birds," Clemency said.

"Frankly, at times it's baffling," Hartup said, but as troubling as it is, "the thing is, it requires a good deal of patience."

Many of the nesting birds will be 6 to 8 years old this spring. In the life of a crane, the birds are still young, inexperienced parents, he said. Some are struggling to pair off; others have lost mates. Also, the birds were born and raised artificially, and he said this might affect their habits as young adults.

The only crane born in the wild in the Eastern flock was in 2006.
A possible destination is Horicon NWR, also in Wisconsin, which may have a lower black fly population than Necedah.

Sunday, March 21, 2010

Great Swamp Herpefauna

I was at the Great Swamp NWR yesterday in search of early spring migratory birds. I saw my first returning Eastern Phoebe of spring migration. (I did see an overwintering phoebe during the C&O Canal Count in January). Waterfowl were in low numbers, but there was a diverse mix of species visible from the blinds. I enjoyed hearing a pair of Red-shouldered Hawks as well.

However, reptiles and amphibians were far more noticeable than birds. Lots of Spring Peepers were evident around the swamp. I saw none but heard their peeping calls. In addition to the peeping, I heard some rising trills that I could not quite place. It was similar to the call of Gray Treefrogs, except that the audio samples I have heard of that species are of trills on an even pitch rather than a rising one.  

Update: I now think that the trills were from New Jersey Chorus Frogs. Both New Jersey Chorus Frogs and the similar Upland Chorus Frogs occur in Morris County, but New Jersey Chorus Frog is more likely to be encountered in the Great Swamp according to the refuge's herp list.

Another frog species present was Wood Frog (one is shown above). These frogs were calling in groups in several shallow ponds along the boardwalk trails. Wood Frogs have already laid a lot of eggs, as evidenced from the many egg masses, but are still very actively courting and mating.

In addition to the frogs, many snakes were active. Most of the ones I saw were taking advantage of the warm day and sunning themselves. I saw two Garter Snakes, neither of which was in a good spot for me to photograph it. The Northern Water Snake below was both photogenic and cooperative, as it stayed in the same position despite much activity on the boardwalk nearby.

This snake was sunning on a branch over the pool where I photographed the Wood Frogs. Water snakes prey on frogs, among other things. As I photographed the snake and listened to the frogs, I was reminded of a series of photos taken by one of my Flickr contacts of a water snake eating a bullfrog. The rest of the series is in the same set.

Saturday, March 20, 2010

Spring Crocuses

Yesterday the temperature climbed to near 70°F, and the crocuses I had noticed sprouting last week were in full bloom.

Friday, March 19, 2010

Loose Feathers #230

Birds and birding news
Birds in the blogosphere
Environment and biodiversity
Blog carnivals

Thursday, March 18, 2010

I and the Bird

I and the Bird #121 is online at Birder's Lounge.

High Arctic Species Doing Poorly

While low Arctic and sub-Arctic wildlife has been doing rather well, high Arctic wildlife have been doing very poorly, according to the latest Arctic Species Trend Index. Overall there has been a 26% decline in high Arctic populations over the past few decades.
Populations of lemmings, caribou and red knot are some of the species that have experienced declines over the past 34 years, according to the first report from The Arctic Species Trend Index (ASTI), which provides crucial information on how the Arctic's ecosystems and wildlife are responding to environmental change.

While some of these declines may be part of a natural cycle, there is concern that pressures such as climate change may be exacerbating natural cyclic declines....

Data collected on migratory Arctic shorebirds show that their numbers have also decreased. Further research is now needed to determine whether this is the result of changes in the Arctic or at other stopover sites on their migration.

Louise McRae adds: "Migratory Arctic species such as brent goose, dunlin and turnstone are regular visitors to the UK's shores. We need to sit up and take notice of what's happening in other parts of the world if we want to continue to experience a diversity of wildlife on our own doorstep."
The report was prepared as the Arctic Species Trend Index on the basis of about 1,000 datasets; the full report is available on the index website. The BBC has a photo gallery of some of the declining species.

Wednesday, March 17, 2010

Review: Birds of Europe: Second Edition

Ever since the publication of its first edition in 1999, Birds of Europe by Lars Svensson, Killian Mullarney, and Dan Zetterström has been regarded as a standard among field guides. The authors just published a second edition, which incorporates new methods for separating some familiar species and taxonomic changes that have occurred since 1999. The new edition has accounts for 41 new species, as well as improved accounts for some distinctive subspecies, so that many plates have been redesigned. Birds of Europe covers Europe east to the Urals and Caspian Sea, North Africa (south to 30°N), and a portion of the Middle East that borders the Mediterranean or Black Sea. The guide gives full treatment to 713 species and covers 91 others (extralimital or exotic birds) in brief.

The introduction includes helpful diagrams of bird plumage and defines birding terms that might not be familiar to all readers, such as names for plumage cycles and body parts. It explains how molt cycles work and how these can be used in the identification process. It also has advice for learning how to identify birds.

Birds of Europe is slightly taller and thicker than The Sibley Field Guide to Birds of Eastern North America, but smaller than The Sibley Guide to Birds.* It feels slightly heavier than The Sibley Field Guide to Birds of Eastern North America. It is small enough to fit in a coat pocket, but too large for pants pockets. According to the preface, the number of pages in this edition is about 10% more than in the first edition. The book is on the large side for a field guide but definitely portable enough to be used in the field.

Birds of Europe has some of the best illustrations I have seen in any field guide. Illustrations are of high quality and show most plumage types for each species. Birds within a family are shown in the same postures to allow for easy comparison of similar species. In addition to the standard poses, the guide shows images of birds within their natural habitat, in some typical behavior that a birder might encounter. Gulls, for example, as shown loafing on a sandbar; Common Buzzard is shown with a rabbit under its talons; rails are shown foraging in a marsh; Dipper is shown on a snowy streambank. These illustrations are valuable as they provide hints about where to expect a species to show up and what it might be doing. In addition to illustrations, there are notes on habitat, identification, and voice for each species. These accounts are presented on pages facing the plates for easy reference between the two. The identification notes are often quite detailed, especially for difficult species.

Difficult families, such as gulls and shorebirds, have lengthy introductions with tips for identifying species within the group. The introduction for gulls explains how molt cycles work in that family. It includes illustrations for the complete cycles of Black-headed Gull (representing two-year gulls), Common Gull (for three-year gulls), and Herring Gull (for four-year birds). Species accounts for gulls generally only illustrate the winter plumage for each cycle. Most families do not receive such detailed treatment.

If there is a drawback to this guide, it is that many of the passerine species are not illstrated in flight. I find flight illustrations useful even on perched birds because birds do not always present themselves in the side view shown in most field guides. A flight illustration can show features of the back or underside that are not as obvious in a side view.

Birds of Europe: Second Edition is the best field guide I have yet seen and surpasses even David Sibley's excellent work. North American birders probably do not need it for birding on this continent, as the most likely vagrants from Europe are adequately treated in North American field guides. However, if you are birding in Europe, if you want to seek out European vagrants in North America, or if you just want to look at better illustrations of Europe's avifauna, this is the guide to get.

* I compare new field guides to these two guides since most North American birders will be familiar with them.

Lars Svensson, Killian Mullarney, and Dan Zetterström. Birds of Europe: Second Edition. Princeton, NJ: Princeton University Press, 2010. Pp. 448; illustrations and maps. $29.95 paper.

This review is written on the basis of a review copy of the second edition provided by Princeton University Press. 

Tuesday, March 16, 2010

Eastern Birds Shrinking in Response to Climate Change

Scarlet Tanager / Photo by Vincent Lucas (a.k.a. leppyone)

Occasionally I see questions about why bird banding is useful (or even assertions that banding is outdated). Banding can serve a variety of purposes, from identifying the birds present at a location to tracking individual birds to studying avian diets or environmental toxins. Here is one example of how even the most basic measurements can be useful, if they are done consistently over a long period. A station in western Pennsylvania has been banding birds since 1961 and taking measurements of the birds' weight and wing chord. ("Wing chord" is the distance from a bird's wrist to the tip of the primaries.) Over the period from 1961 to 2007, the birds' measurements steadily decreased.
They examined the records of 486,000 individual birds that had been caught and measured at the ringing station from 1961 to 2007.

These birds belonged to 102 species, arriving over different seasons. Each was weighed. It also had the length of its wings measured, recorded as wing chord length, or the distance between the bird's wrist to the tip of the longest primary feather.

Their sample included local resident bird species, overwintering species, and even long distance migrants arriving from the Neotropics.

What they found was striking.

Of 83 species caught during spring migration, 60 have become smaller over the 46 year study period, weighing less and having shorter wings.

Of the 75 species migrating in autumn, 66 have become smaller.

In summer, 51 of 65 breeding species have similarly reduced in size, as have 20 out of 26 wintering species.

The differences in size are not big.

"On average, the decline in mass of spring migrants over the 46 year study was just 1.3%," says Dr Buskirk.

"For a 10g warbler that's a loss of just 130mg."

But some species are losing more weight.

For example, the rose-breasted grosbeak has declined in mass by about 4%, while the Kentucky warbler has dropped 3.3% in weight and the scarlet tanager 2.3%.
According to a biological principle known as Bergman's Rule, individuals that live further north will be slightly larger than individuals within the same species that live further south. The reasons for the link between climate and size are unclear, but the link is well attested. Thus if the climate is warming, one would expect birds to become gradually smaller. That appears to be what is happening in this case. The link to warming is strengthened by the fact that species that spend part of the year in the tropics have shrunk faster than resident species.

Whether this will affect the birds species' long-term viability remains to be seen. So far, there does not seem to be a link between smaller physical size and population declines. Many of the species that have decreased in physical size are doing quite well otherwise. Those populations threatened by climate change appear to be struggling with other climate-related problems, such as droughts or the timing of migration. Still, the trend is worth monitoring, for what it tells us about the changing climate and the bird populations.

Monday, March 15, 2010

Flooding on the Raritan

There is a saying that March comes in like a lion and goes out like a lamb. This year March saved the lion part for the middle of the month. Over the weekend, we had a major winter storm with heavy wind and about four inches of rain in 48 hours (some places got more than that). As result the river flooded any low-lying areas, such as my local park.

Someone flooded the bathrooms.

Of course, the local Canada Geese took full advantage of the expanded waters.

For the sake of comparison, the view from the top of the hill should look something like this (in summer).  The benches in the top photo are these ones.

Some towns fared far worse; in Bound Brook, where the river crested at 31.45 feet, the police had to patrol the streets on jetskis and rubber dinghys to evacuate residents. In Highland Park, the water only reached about 15 feet, which is not sufficient to flood the town. Even so, this was the highest I have seen the river in a long time. Newspaper accounts compared it to the aftermath of Hurricane Floyd.

Sunday, March 14, 2010

Predicting the State of the Birds

Last week, the Interior Department, Audubon, and a coalition of other conservation-minded organizations announced the 2010 State of the Birds report. (Oddly, the report was released late on a Thursday; usually the end of the week is reserved for news that agencies would prefer people not notice, like bank failures.) This year's report tries to predict how birds might respond to climate change. It suggests conservation actions to mitigate those responses and reduce stress as the climate continues to warm.

Relative vulnerability of U.S. birds by habitat

The report divides birds into groups based on broad habitat types or location. Since this was produced in part by the Interior Department, the report includes all birds found in the United States and its territories, including islands in the Pacific and West Indies. Each bird species was assessed on five traits and rated as high, medium, or low vulnerability based on that assessment. Here, briefly are some of the report's predictions.
  • Oceanic birds will face changes in prey distribution, which will affect the viability of breeding colonies. In addition, sea level rise may threaten low-lying colonies.
  • Coastal birds, which use beaches and salt marshes, face threats from sea-level rise, both from permanent inundation of some low-lying areas and from increased flooding and erosion.
  • Arctic and alpine species are handled together because they face the similar problem of having few options for moving to more suitable areas as their current habitat warms. Arctic birds are often long-distance migrants, so they face climate-related changes all along their migration routes. In the Arctic, melting permafrost could release additional toxins and allow woody plants to encroach on tundra habitat.
  • Island birds (both Pacific and Caribbean) are particularly vulnerable if they are endemic to an island, as is true of 42 Hawaiian bird species. A warming climate could create significant changes in precipitation; this would affect the vegetation and insect life that birds depend on.
  • Aridlands will become warmer and drier, which will fundamentally change the vegetation structure in many areas. As precipitation decreases, riparian habitats will shrink, along the bird populations that depend on them. Some species may get a boost as arid habitats are expected to expand to the north and east.
  • If temperatures increase without a corresponding increase in precipitation, wetlands could shrink considerably from evaporation and loss of input. Mountainous wetlands and the prairie pothole region are particularly vulnerable. 
  • Grasslands are expected to become drier, and continuing increases in atmospheric carbon dioxide could encourage woody plants to encroach on grassland habitat. The vulnerable grassland birds are those that are less likely to move in the face of changing habitats, such as grouse. 
  • Forest types are likely to shift northward; oak-hickory and oak-pine forests will expand considerably, while other types will contract within the United States. The boreal forest will shrink somewhat as its southern border moves north. Most forest birds are not at high risk because they reproduce quickly, but species that rely on a single forest type will face challenges.
The predictions discussed in this year's report are not for changes far off in the future. In some cases, they are happening already. Bird species are known to be shifting their winter ranges northward, based on Christmas Bird Count data.

For more details, including recommended conservation measures, see the full report.

Mitigation is going to become increasingly important as the climate continues to warm. At this point it seems unlikely that we will see effective action from the U.S. Congress on climate change. Even if the EPA is successful in imposing greenhouse gas restrictions, its restrictions may not reduce emissions quickly enough. So we are likely looking at some pretty dramatic changes over the next few decades, and long-term conservation plans will need to account for that.

Saturday, March 13, 2010

Update on the Bahamas Piping Plovers

Piping Plover at Little Talbot Island / Photo by Pat Leary

One of the color-marked Piping Plovers from Andros Island in the Bahamas has been resighted. The bird pictured above was captured and banded on February 17 on Andros Island. Pat and Doris Leary found it while birding at Little Talbot Island in Duval County, Florida, on March 12. This bird was the last plover to be marked and the first to be resighted. From Andros Island to Little Talbot Island is about 440 miles by air.

I did not see any plovers while I was at Sandy Hook last weekend, but I will be watching for them when I am at coastal spots. For updates on the plover marking project (and other bird banding activity), follow the CVWO First Landing blog.

DNA from Fossil Eggshells

One item that I did not see in time for yesterday's Loose Feathers post is the news that scientists have isolated DNA from the fossilized eggshells of extinct elephant birds.
"We were really surprised to discover that ancient DNA is well-preserved in fossil eggshells, particularly the heaviest bird to have existed the elephant bird called Aepyornis, which is now extinct," said Murdoch doctoral student Charlotte Oskam, who undertook the research.

"Researchers have tried unsuccessfully to isolate DNA from fossil eggshell for years -- it just turned out that they were using a method designed for bone that was not suitable for fossil eggshell."

The new study published this week in the scientific journal Proceedings of the Royal Society B describes how DNA up to 19,000 years old is an excellent source of ancient DNA especially in warmer climates such as Australia.
The research team hopes to use the same methods for ancient moa eggshells to study how humans and moas interacted. Extracting DNA from fossil remains could probably clarify some taxonomic relationships as well.

If you wish to read about this study in more detail, you can read the paper for free on the Royal Society's website.

Friday, March 12, 2010

Loose Feathers #229

Loggerhead Shrike / Photo by Dave Menke (USFWS)

Birds and birding news
Birds in the blogosphere
Environment and biodiversity

Thursday, March 11, 2010

ESA Protections for Loggerhead Sea Turtle and Kaua'i Endemics

Last week, I expressed some frustration with the Obama's administration's record on endangered species after it placed Greater Sage-Grouse on the list of candidates. Up to that point, only two species had been listed under the Endangered Species Act since Obama took office, while 249 species have been sitting on the candidate list. This week that changed in a big way, with two announcements.

Loggerhead Sea Turtle at Archie Carr NWR / Photo by Ryan Hagerty (USFWS)

First, the National Marine Fisheries Service and U.S. Fish and Wildlife Service issued a joint proposal to list the Loggerhead Sea Turtle (Caretta caretta) under the Endangered Species Act. Loggerhead Sea Turtle has nine distinct populations around the world. Of these, two will be designated as threatened and seven as endangered. The two populations that occur in U.S. waters, the North Pacific and Northwest Atlantic populations, will both be designated as endangered. Loggerhead Sea Turtles worldwide are currently classified as threatened; the new listing is in response to petitions regarding the two U.S. populations.

This is a proposed rather than final rule, so it will undergo a public comment period first. If you wish to comment on the proposed listing, you can do so at until June 14, 2010. Once the Loggerhead is listed as endangered, the government will be required to designate critical habitat to protect feeding areas in the ocean and nesting areas on beaches.

‘Akeke‘e (Loxops caeruleirostris) / Painting by John Gerrard Keulemans

Second, 48 endemic species from the Hawaiian island of Kaua'i were listed as a group since they share habitats and have similar threats. This action addresses some of the backlog in listing petitions. An ecosystem approach is particularly suitable for Hawaii since so many vulnerable species occur in a relatively small area. It provides a way for the government to protect entire ecosystems rather than the narrow ranges where a species is known to be found. The USFWS plans to list new species by ecosystem on other islands in the next few years.

The 48 newly listed species (pdf) include 45 plants, 1 insect, and 2 birds. Among the 45 plants are several that have not been seen for several years, though they still exist in remote areas. One plant, Diellia manii, was considered extinct until its recent rediscovery. The insect is Drosophila sharpi, a Hawaiian picture-wing fly. The two birds are ‘Akeke‘e (Loxops caeruleirostris) and ‘Akikiki (Oreomystis bairdi). Both are Hawaiian honeycreepers and members of the finch family. They may be better known as Kaua'i 'Akepa and Kaua'i Creeper. These species had appeared stable until the mid-20th century, when both populations suffered precipitous declines. There are now about 3,500 'Akeke'e and 1,300 'Akikiki.

Along with listing the 48 endangered species, the USFWS designated critical habitat for 47 of them. The critical habitat covers 26,582 acres in six ecosystem types, 98% of which overlaps the critical habitat already designated for other endangered or threatened species. Most is on state-owned lands. Critical habitat was not designated for one palm species because it is a prized plant for collections; the USFWS was concerned that designating critical habitat might alert collectors to its location.

Wednesday, March 10, 2010

Pelicans Starving?

A couple weeks ago, I posted about the extraordinary number of suffering Brown Pelicans that have been washing up on California's beaches this winter. The state's wildlife agencies now have an answer: food supplies are low.

The California Department of Fish and Game (CDFG) is reporting that the primary causes of the recent Brown Pelican mass stranding (involving varying degrees of incapacitation of hundreds of birds) along the Oregon and California Coast are related to shortages of preferred prey items, such as anchovies and sardines, and rough winter weather likely related to the current El Niño event.

CDFG, the U.S. Geological Survey National Wildlife Health Center, Sea World San Diego and the International Bird Rescue Research Center (IBRRC) pooled their efforts to determine the causes for the bird deaths and strandings, and ruled out infectious disease and marine toxins as major contributory factors. Some pelicans have had waterproofing problems with their feathers, possibly related to storm runoff from recent heavy coastal rains.
The IBRRC is caring for 300 birds right now, but at least the number of new patients is decreasing. Sick pelicans have responded well to treatment (mainly washing and feeding), and the center has been releasing rehabilitated pelicans in batches. (As of February 19th, 200 pelicans had been released.) I do not see anything about the CDFG announcement yet, but the IBRRC blog is a good place to check for updates on the pelicans.

Tuesday, March 09, 2010

Everglades Land Purchase Not Going According to Plan

Two years ago the state of Florida made national headlines by announcing that it would purchase the moribund U.S. Sugar company and its assets, including 187,000 acres in the Everglades, for $1.75 billion. Major environmental groups praised the move because it had potential to help restore the natural flow of the Everglades from Lake Okeechobee south to the Gulf of Mexico (for example). At the time, I worried about the financing of the plan, which was left rather vague in the initial announcements. The state of Florida has financial problems almost as severe as California's, and taking money out of the water district's budget would impede other necessary restoration projects that had already begun.

The problems were worse than I imagined. The state has since scaled back the deal, so that it will now purchase only 72,800 acres for $536 million. Meanwhile, U.S. Sugar will retain the rest, including its production facilities, and remain in operation for the foreseeable future. In fact, this deal may do more to revitalize U.S. Sugar than the Everglades.
Negotiations favored United States Sugar from the start, when the state accepted two outside firms’ appraisals of the company’s land that used figures from the height of the real estate market, according to documents.

When a “fairness opinion” commissioned by the state found that those appraisals had overvalued the land by $400 million, Florida officials orchestrated a public relations campaign to discredit the findings, internal e-mail showed. Appraisers from the Florida Department of Environmental Protection, which was required to sign off on the deal, were also cut out of the process after raising concerns, e-mail messages showed.

When it came time to decide which land to buy, state officials acknowledged that United States Sugar was, as one official put it during an interview, “pretty much in the driver’s seat.” The water district overseeing the restoration will end up with six large disconnected parcels under the current deal, including all of United States Sugar’s citrus groves.

State officials acknowledged that some of that land, which has been ravaged by canker, a plant disease, is useless for restoration.
Some elements of this case ought to be scandalous. Why were terms of the purchase so favorable to U.S. Sugar and why were key parties – like a rival company, federal agencies, and the Miccosukee Indian tribe – shut out from the process? Part of the reason is that U.S. Sugar has close ties to Charlie Crist:
United States Sugar had an unusually powerful advocate in Gunster, a West Palm Beach law firm that had represented it since 1990. Gunster’s chairman, George LeMieux, was Governor Crist’s chief of staff when the deal was first conceived. Mr. LeMieux, who began working at the law firm in 1994, returned to it in January 2008 as the deal was being renegotiated.

He and Mr. Crist are confidants, and the governor referred to Mr. LeMieux as the “maestro” of his 2006 election victory. When a United States Senate seat was vacated in 2009, Mr. Crist appointed Mr. LeMieux to fill it. The governor is now campaigning for that post and has often described the United States Sugar purchase as a crowning achievement of his administration.
While LeMieux claims to have recused himself from the deal, his close ties with Crist would have given U.S. Sugar an inside edge on negotiations. Even if LeMieux did not talk to Crist about the deal, he did advise U.S. Sugar during the process.

Another reason the terms were so favorable is that Crist's negotiators chose to accept the land appraisal most favorable to U.S. Sugar, even though other independent appraisers and the state's own environmental agency thought that the land was overvalued, even at the time. Since then the land's market value has declined due to the crash in the real estate market. According to some estimates, the state agreed to pay $7,000 an acre for land that is now worth $4,000 per acre. Much of the remaining land in the deal is heavily contaminated with copper, DDT, selenium, and arsenic. Cleaning up that mess will cost even more. Some areas to be purchased by the state, such as the company's citrus groves, are too elevated and dry to be suitable for wetlands restoration.

This would be just another corrupt land deal if it were for for its potential to set back restoration efforts in the Everglades. Already completion of a giant reservoir costing $800 million – a key piece in the system of canals and reservoirs to restore the natural flow – has been stalled indefinitely because of the purchase. The cancellation of construction contracts cost the state $25 million in fines, on top of the $282 million it had already spent on the project. Whether other projects will need to be canceled remains to be seen. The U.S. Sugar deal may still turn out to be worthwhile, but for now it is an obstacle to completing the original restoration plan.

Monday, March 08, 2010

Photos: Sand Ripples

The bay side at Sandy Hook is subject to strong tidal action from Raritan Bay. In sheltered spots, the receding water leaves interesting shapes in the sand. On Saturday, I photographed some of the ripples left by the sand. One area struck me as looking like a canyon in miniature.