Bird Diversity and the West Nile Virus

Last week, PloS ONE published an interesting paper that argues that a diverse bird population lowers the human risk of contracting the West Nile Virus (WNV). The study compared WNV infection rates in sixty-five pairs of neighboring counties, in which one county had human WNV infections and the other did not, while both had infected birds. (One of the pairs included my home county, Middlesex, and its neighbor to the west, Somerset.)

The paper measured the inter-county contrast in human infection rates against the contrast in various measures of avian biodiversity. (Bird population data was derived from the Breeding Bird Survey.) It found that greater bird diversity correlated with fewer human infections. Avian biodiversity explained about 30% of the contrast.

The reason is something called the "dillution effect," which was first observed with Lyme disease transmission. The mechanism for the dillution effect is unclear; none of the proposed mechanisms matched up with the data in this paper's analysis. However, it seems to be related to the greater relative abundance of species that are poor hosts for the disease compared to species that are more susceptible. In the case of WNV, highly-susceptible species such as crows and robins tend to predominate in areas of lower bird diversity, so the disease will have plenty of hosts and a greater likelihood of spreading beyond birds.

Here are a few interesting points from the analysis:

1. The analysis confirms that robins play a role in spreading WNV to humans. This has been reported in other studies, including one in Washington.
2. Unsurprisingly, corvids (crows, jays) are associated with human infections.
3. Surprisingly, finches also seem to be associated with human cases of WNV. I had not heard of finch susceptibility before reading this paper.
   
4. Passerines as a group appear to be resilient in the face of WNV outbreaks, at least in the initial stages of an epidemic. This seems to contradict some previous reports, but perhaps not. The authors suggest that many passerine species may be poor hosts.
   
5. Non-passerines seem much more susceptible to WNV than previously thought, so there may be many susceptible host species outside of Passeriformes.
   

As Mike wrote, studies like this provide us with a self-centered rationale for maintaining a diverse avian population. When we promote wildlife conservation, we are also promoting our own health.

From my own persepective, it may support conserving wildlife within cities as well as outside of them. Many environmentalists and urbanists argue that urban parks should not be wildlife habitat and should be for people instead. (I do not think those goals are always in conflict, but the argument exists.) This paper provides an example of how increasing local biodiversity can be beneficial to humans in concrete ways. In the case of WNV, the dillution effect works independently of relative urbanization. This suggests that perhaps a diverse wildlife population should have a place in urban planning.

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Blog Note: I will not have internet access for the next few days, so I have prepared several posts to publish automatically. (If you do not know how to schedule posts, see here.) Though the blog will have the regular posting schedule, I will not be able to respond to comments or email until later in the week.

Everglades Funding

Last week, when Florida announced that it would buy U.S. Sugar properties in South Florida, it seemed to me that some things were being left unsaid in the initial wire reports. I was particularly concerned with the funding for the purchase, and wondered if any other problems were lurking. (Yes, the last eight years have made me very cynical, indeed.) It turns out that funding is a problem in the Everglades deal.

But the deal will also tie up much of the state's share of Everglades funding -- at a time when budget worries have delayed other projects in the restoration plan. Federal funds have been so scarce that the U.S. Army Corps of Engineers, which is co-managing the restoration, has been ordered to slash project costs.

The state typically spends about $325 million a year on Everglades projects, said Tom Olliff, the district's assistant executive director. But the debt payments on the $1.7 billion sugar deal will eat up as much as $153 million of that each year.

The water district should still have about $170 million a year to spend on other Everglades projects and land purchases, Olliff said. But some of that money must be approved annually by the Legislature, which cut Everglades funding for the budget year that begins Tuesday.

No one has drawn plans for building on the U.S. Sugar property, but any combination of new reservoirs and marshes would certainly add billions of dollars to the price tag. For example, a 16,000-acre Everglades reservoir under construction in Palm Beach County is expected to cost taxpayers about $800 million.

Restoration of natural flow from Lake Okeechobee to Everglades National Park also seems unlikely, despite initial reports.

''It's a lovely concept,'' said Carol Ann Wehle, the water management district's executive director. But ``you are never, ever going to have sawgrass marsh there.''

Planners say the sugar fields south of the lake have lost too much earth to farming, leaving a deep bowl that would prevent any water from flowing to the south without artificial pumps. Studies also have shown that converting the sugar fields to marsh would produce so much evaporation that the Everglades could wind up with less water.

In any case, Lake Okeechobee's water is simply too polluted to pour directly into the Glades. A reservoir would allow water managers to manipulate water depths and move it where it's needed depending on rainfall and seasonal conditions.

There are other issues as well; in particular, indigenous tribes living in the area do not seem to have been consulted by the state. There is plenty more discussion at the link.

The deal was still worth doing, even if it temporarily stops some of the other restoration projects. U.S. Sugar's cessation of operations will remove at least one major water user and polluter. That seems to be a step in the right direction, even if its potential takes a long time to be realized.

The Canary Effect

Last year, lead dust in the town of Esperance, Australia, killed 4,000 birds. The dust's source was a shipment of lead from Magellan Metals' Wiluna mine that passed through Esperance. A year later, the problem persists.

Dr Nic Dunlop, who contributed to the study, says it found most birds recorded lead levels 10 to 100 times higher than normal.

He says the contamination is likely to cause more bird deaths.

"Now the problem is over time, they will increasingly ingest that lead, either through preening or through their food, so it's quite likely as time goes on that we will get a second wave of impact on birds and other wildlife as a consequence of that lead," he said.

The Planning and Infrastructure Minister Alannah MacTiernan says the study is outdated.

She says the Government is constantly monitoring lead levels in the area.

"Since then we have done another comprehensive clean up at the port and since then all of the other tests that we have done all of the tests, November, December, January, February, March are all showing improvements in the outcomes in fact quite dramatic improvements," she said.

It is a very sad situation, and one that must be unsettling for the town's residents. So far I have not heard about any human casualties from lead pollution in Esperance, but I am sure that it is having an effect – if not among adults then among children. This is one reason that it is good to keep birds around: they are much more sensitive to changes in the environment, and sound the alarm when something is wrong.

Interview with Barbara Boxer

Last night Bill Moyers interviewed Senator Barbara Boxer (D-CA) on the Bill Moyers Journal. The segment covers the 20th anniversary of James Hansen's initial warning about climate change in 1988, Boxer's conflicts with Senator James Inhofe (R-OK), and the recent demise of the Lieberman-Warner Climate Security Act.

Unfortunately PBS does not make it possible to embed its videos, so you will have follow the link to the PBS website to watch it.

Why Migration Changes Matter

In yesterday's Loose Feathers, I linked to a story about how migratory birds have adjusted to climate change (or not, in some cases), according to the records at the Manomet research station. Basically, the short-distance migrants, like swamp sparrow, were able to adjust their schedules to keep pace with a warmer climate because the temperatures on their wintering grounds are pretty similar to the temperatures at Manomet, and follow similar cycles. Meanwhile, the long-distance migrants, like great-crested flycatcher, winter in the tropics and do not have the same temperature cues as a bird in the temperate zone. So they have not adjusted their schedules.

The reason this is important is that a warming climate is also changing what the birds will find when they get to their destinations. Consider the following two news reports, both issued yesterday.

First, the types of fish prevalent in Narragansett Bay and Rhode Island Sound have changed over the past fifty years.

According to Jeremy Collie, professor of oceanography at the University of Rhode Island's Graduate School of Oceanography, the fish community has shifted progressively from vertebrate species (fish) to invertebrates (lobsters, crabs and squid) and from benthic or demersal species -- those that feed on the bottom -- to pelagic species that feed higher in the water column. In addition, smaller, warm-water species have increased while larger, cool-water species have declined....

"While we're catching more fish now, we're also catching smaller fish," said Collie, "and that corresponds with how the preferred temperatures of the fish here have changed. The fish community now is dominated by warm-water adapted species compared with what we started with, and fish that live in warmer water are smaller."

Collie added that fishing may also be a factor in the decline in fish size, since fishing removes the largest individuals from a population while leaving the smaller ones. However, he believes that climate is "the dominant signal." Sea surface temperature in the area of the trawls has increased by 2 degrees Centigrade since 1959, and the preferred temperature of the fish caught in the trawls has also increased by 2 degrees C.

Second, plants in Europe are climbing mountains at a rate of 29 m per decade.

Professor Lenoir, an ecologist at AgroParisTech, France, said the team wanted to establish whether "fingerprints of climate change were already apparent in ordinary ecosystems".

In order to do this, the team of French and Chilean researchers compared the distribution of forest species between 1905 and 1985 with their distribution between 1986 and 2005....

"We used 171 species commonly found over French mountains, which are part of Mediterranean, temperature and mountainous forest ecosystems between 0m to 2,600m above sea level.

"We found a significant change in species' altitudinal distribution towards higher elevation of about 29 metres per decade.

"Out of the 171 species, most are shifting upwards to recover temperature conditions that are optimal for their development and reproduction."

These may serve as examples of how local ecosystems are changing rapidly in the face of warmer climates. Similar trends occur in phenomena more closely related to the timing of bird migration. A warmer spring may prompt plants to sprout, flower, and leaf more quickly. This in turn will affect any associated insects – either pollinators or leaf-eaters. The insects will either hatch and breed earlier, or keep to their schedules and have less to eat as a result.

Birds that time their migrations to take advantage of floral nectar (hummingbirds) or abundant insects (flycatchers and other insectivores) will find food scarcer than it used to be. Flowers and insects may already be past their peak by the time the birds arrive. Adjusting their migration schedules is absolutely crucial to their survival in a warmer climate.

Loose Feathers #155

California Quail / Photo by Lee Karney (USFWS)

Bird news

• A paper in Science may make our field guides obsolete. Genetic analysis by the Early Bird project of 169 bird species, representing all major groups, revealed that much of current bird taxonomy is wrong and that many bird groups that appear to be similar evolved separately. For example, falcons are more closely related to parrots and songbirds than to hawks and eagles. The most thorough account of the findings that I have seen so far is at Living the Scientific Life. Science Daily has a good write-up, too. National Geographic illustrates some of the new sister clades.
• Scientists at Manomet on Cape Cod analyzed data for 32 bird species and found that eight of them migrated past the observatory much earlier than they did 38 years ago. These eight are short-distance migrants coming from elsewhere in the U.S. and can adjust their migration schedules to keep up with earlier springs. Birds that winter in Central or South America have not adjusted as well because they do not have the same temperature cues.
  
• A preliminary study in 2007 at Judith Gap Wind Energy Center found 1,206 bats and 406 birds died from turbine-related causes. The wind farm is the largest in Montana. ABC has a round-up of recent work on mitigation measures to prevent wind farm deaths.
  
• Agribusiness and ethanol lobbyists are pushing the federal government to allow farmers to plant corn on land that is currently in the Conservation Reserve Program. The CRP is the largest federal land conservation program and benefits many species of birds.
• White storks have benefited from a reintroduction program in Alsace and Lorraine. Twenty-five years ago, only 9 stork pairs were left in the Upper Rhine Valley; now there are 270 pairs.
  
• Eight captive California condors had to be evacuated from the Ventana Wildlife Society due to a nearby wildfire.
• The white-winged flufftail is an endangered species about which little is known, including whether it migrates. The lack of information frustrates conservation action plans.
  
• The RSPB is working with hunting groups to reduce raptor killings on private lands.
• Illinois is re-evaluating its state list of threatened and endangered species.
• The Guardian has a gallery of the most aggressive birds.
• Another gallery shows a heron grabbing and eating a duckling.
  
• Here is a profile of the naturalist at Cheesequake State Park (New Jersey).
• The CLO has free resources available for teachers and parents who want to do citizen science projects in urban areas.
  

Birds in the blogosphere

• Bug Girl: Aquatic Mercury in Food webs
• Picus Blog: Mississippi Kites in Newmarket, NH
  
• Rigor Vitae: English Sparrow Update (on predation by other birds)
• 10,000 Birds: Green Herons and their Groovy Necks
• Ecobirder: Yellowstone Barrow's Goldeneye
• Birdfreak: Bird Conservation - Prothonotary Warbler
• BES Group: White-throated Kingfisher: Non-iridescent colours
  
• Birds and Things: English Sparrows Seen As A Nuisance
• Zen Birdfeeder: Adirondack Loon Census July 19th (volunteers needed!)
  

Environmental news

• California has announced a plan to cut state greenhouse gas emissions to 1990 levels by 2020.
  
• Brazil seized 3,100 cattle that were grazing on illegally-cleared rainforest land.
• A sugar cane biofuels project in Kenya threatens to destroy the country's most diverse wetlands. The Tana Delta wetlands are home to 345 species of birds and support the livelihoods of thousands of farmers and fishermen.
• One result of Florida's purchase of U.S. Sugar lands is that it removes a political obstacle from Everglades restoration.
  
• A proposed coal-fired power plant in rural Virginia has drawn heavy opposition from residents.
• A study of the impact of acid rain on microorganisms in Adirondack lakes found that high acidity reduced overall bacterial diversity, but increased some rarer forms of bacteria.
• According to the Energy Information Administration, expanding offshore drilling would do little to change gasoline prices.
  
• James Hansen: Twenty Years Later
  

Carnivals and newsletters

• I and the Bird #78
• Tangled Bank #108
• Carnival of Environmental Issues #24
  
• Birds in the News #136
  

I and the Bird

The latest I and the Bird is online at It's Just Me.

How Singing Helps Warblers Find Breeding Habitat

Spring is accompanied by an explosion of birdsong that lasts well into the summer. Every morning for the past few months I have woken to the sound of a catbird singing outside my window. We are all familiar with the role birdsong plays in the early breeding season. Males sing to win and defend their territories and, in turn, attract females to mate with them. As the breeding season progresses, continued singing by adults helps juvenile birds learn to sing. It turns out that late season singing has one more function: it helps fledglings find appropriate breeding habitat for the following year.

That was the conclusion of a recent study involving one of my favorite birds, the black-throated blue warbler (Dendroica caerulescens). The researchers wanted to test whether social cues, such as late season birdsong or the presence of fledglings, helped other birds determine which sites had the best potential for breeding.

They set up 54 test sites in White Mountain National Forest in places with inappropriate habitat (to eliminate the possibility that birds followed vegetation cues rather than social cues). At the end of the breeding season in 2006, each site was given one of three treatments: left alone (a control group); song playbacks with male decoys (location cues); song playbacks with male decoys, plus female decoys attending fledgling decoys with with playbacks of begging calls (public information).

That summer, the researchers checked all three types of sites for the presence of black-throated blue warblers that might be looking for future breeding habitat. Sites with an artificial social cue were more likely to receive visits from fledgling warblers than the control sites. Both males and females were observed at the test sites.

The following year (2007), researchers conducted point counts at the test sites to check for warbler activity. Male warblers were far more likely to set up territories at sites where they had heard playback of territorial songs or fledgling calls the year before than at control sites. Females seemed to follow the presence of males; females were observed only at test sites where a male warbler was present.

Since warblers were equally likely to return to sites with location cues (song playback) and public information (song playback and dummy nests), the researchers surmised that late-season birdsong alone was a reliable indicator of good nesting habitat. To test this, researchers checked 60 known warbler territories for singing males.

Song frequency within territories was positively correlated with reproductive success, but only towards the end of the period observed.... By late in the breeding season (31 July), singing was 5.1 times (95% CI: 1.89-22.28) more likely on territories that successfully fledged young than those that did not. Conspecific song in the post-breeding season was therefore a reliable indicator of breeding success.

This result may be of interest to birders who volunteer for breeding atlases or other types of nest surveys.

Birdsong turns out to be a complex and powerful communication tool. For a short-lived species such as the black-throated blue warbler, which has to migrate thousands of miles between its wintering and breeding grounds, individual birds have relatively few chances to produce offspring. Reliance on a social cue like birdsong helps young birds avoid making some nesting mistakes in their first breeding season. They thus can produce more offspring over the course of their lives. It also holds advantages for the species as a whole, since local populations will be able to adapt more quickly to changes in their environment.

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Matthew G. Betts, Adam S. Hadley, Nicholas Rodenhouse, and Joseph J. Nocera, "Social information trumps vegetation structure in breeding-site selection by a migrant songbird." Proceedings of The Royal Society B (online edition, published June 17, 2008). doi:10.1098/rspb.2008.0217

Exxon Valdez Award Reduced

The Supreme Court issued its verdict in the Exxon Valdez case today. The justices reduced punitive damages from $2.5 billion to $507.5 million. That works out to about $15,000 per plaintiff.

"The punitive damages award against Exxon was excessive as a matter of maritime common law," wrote Justice David Souter in the majority opinion. "In the circumstances of this case, the award should be limited to an amount equal to compensatory damages."

The court was divided five to three.

The 32,677 plaintiffs in the case have been waiting for their compensation since 1994, when a jury in Anchorage returned a $5 billion punitive-damages award against Exxon Mobil Corp. The company has been appealing the verdict since then. In 2006, the 9th U.S. Circuit Court of Appeals cut the award to $2.5 billion. Exxon appealed that decision to the Supreme Court, which heard oral arguments in the case on Feb. 27.

Business groups such as the American Petroleum Institute and the U.S. Chamber of Commerce had hoped that the Supreme Court would use the Exxon Valdez case as a way to curb what they believe are large punitive damages against corporations.

Former Alaska governors, the current governor, the congressional delegation, supertanker captains, environmentalists, state lawmakers, Alaska Natives and experts in maritime law all joined with the 32,677 plaintiffs in asking that the Supreme Court uphold the $2.5 billion verdict.

This is clearly a big win for ExxonMobil, which has used its financial advantages to delay paying punitive damages for fifteen years while whittling down its size to the point that it is only a tenth of what the jury awarded.

See also: Exxon Valdez spill by the numbers (via)

Update: Here are reactions from residents of Cordova, Alaska, home port of many of the fishermen affected by the spill.

Inconvenient Email: We Pretend It Doesn't Exist

Despite all that we have seen over the past seven (long) years, these reports never fail to amaze me:

The White House in December refused to accept the Environmental Protection Agency’s conclusion that greenhouse gases are pollutants that must be controlled, telling agency officials that an e-mail message containing the document would not be opened, senior E.P.A. officials said last week.

The document, which ended up in e-mail limbo, without official status, was the E.P.A.’s answer to a 2007 Supreme Court ruling that required it to determine whether greenhouse gases represent a danger to health or the environment, the officials said.

This week, more than six months later, the E.P.A. is set to respond to that order by releasing a watered-down version of the original proposal that offers no conclusion. Instead, the document reviews the legal and economic issues presented by declaring greenhouse gases a pollutant.

Over the past five days, the officials said, the White House successfully put pressure on the E.P.A. to eliminate large sections of the original analysis that supported regulation, including a finding that tough regulation of motor vehicle emissions could produce $500 billion to $2 trillion in economic benefits over the next 32 years. The officials spoke on condition of anonymity because they were not authorized to discuss the matter.

In addition to the economic benefits of emissions reductions, the email also included politically inconvenient analysis of the Clean Air Act. It concluded that the E.P.A. could regulate at least some greenhouse gases under current law, while the White House was arguing that the Clean Air Act gave no such authority and that new legislation would be required.

It has become pretty apparent at this point that this administration's goal is simply to run out the clock on greenhouse gas reductions and leave the problem for the next administration to solve. Still, refusing to even open an email, much less answer it, strikes me as particularly petty.

Everglades Land Purchase

Yesterday the state of Florida announced that it would purchase 187,000 acres in the Everglades from U.S. Sugar, the largest domestic sugar company, for $1.75 billion. While the state and the company have agreed to the sale in principle, most of the details will not be completed for another 75 days.

Under the proposal, expected to take 75 days to finalize, U.S. Sugar Corp. would sell some 300 square miles along with two massive refineries, 200 miles of railroad and other assets to the South Florida Water Management District.

The company would then continue farming for six years under a lease with the state before ending operations. The district hopes to swap some of the company's holdings with those of other sugar growers, opening a massive swath south of Lake Okeechobee to construct reservoirs and pollution cleanup marshes that would resolve two of the restoration effort's biggest problems -- the water is still too polluted and there isn't enough of it to restore the natural flow of the River of Grass.

Bob Buker, president of U.S. Sugar, said he was saddened at the thought of a deal that would effectively end his company's long history of farming in the Everglades, but also heartened that it could resolve some of the state's most serious environment issues.

The significance of the deal is that it will allow the state to reconnect Everglades National Park with Lake Okeechobee. Reducing agriculture in the region should reduce pollution levels right away, and further pollution reductions will follow as restored wetlands filter harmful chemicals. According to the L.A. Times, the purchase will eliminate the need for building "intricate dams, canals and pumps" to control water flow, which should save money for other projects. Of course, habitat restoration should help stabilize local bird populations. Overall the purchase seems like a winner.

A massive amount of land is changing hands in return for a massive amount of money. One thing I cannot help but wonder is where that money is coming from. In recent years, Florida has suffered from even worse fiscal management than New Jersey. According to the Miami Herald, funds for the purchase will come out of other Everglades restoration projects, but which ones is not yet clear. The L.A. Times reports the payments will be "$50 million in cash and $1.7 billion in certificates of participation to be sold on Wall Street." Either way, that aspect bears watching.

Relocating a Caspian Tern Colony

The mouth of the Columbia River is home to the largest colony of Caspian terns in the world. At least 9,900 pairs of terns nested on a sandy island there last year. Unfortunately, the Columbia River is also home to endangered salmon and steelhead. Terns eat millions of the juvenile fish each year as the fish migrate towards the Pacific Ocean. So wildlife managers are trying to relocate the tern colony to other sites.

One reason for the super-colony at the mouth of the Columbia River, Roby said, is that the birds' historical nesting sites in the western United States have been destroyed by human activities. The draining of marshland habitat in some locations, and the flooding of historical nesting sites in others, has decimated their favored nesting habitat -- bare sand islands.

Now, working with a plan developed by the U.S. Fish and Wildlife Service, the Corps and NOAA Fisheries, the OSU-led team is starting to restore alternative nesting colonies for Caspian terns. In addition to the Crump Lake site, the Corps created an artificial island in Fern Ridge Reservoir in the Willamette Valley, and plans to build three half-acre islands in the Summer Lake Wildlife Area in southern Oregon this summer and next. The plans at Summer Lake include the construction of a half-acre floating island made of recycled plastic with a coarse sand and gravel surface.

Crump Lake and Summer Lake are historical nesting sites for terns, Roby said, but Fern Ridge is not. And thus far, the terns have been slow to embrace Fern Ridge as a nesting site....

The Caspian tern management project also calls for establishing and/or restoring three alternative nesting sites in the San Francisco Bay area, where the OSU-led team also has a research crew.

If the project succeeds, the colony at the mouth of the Columbia River will still exist, but will be about one-third of its current size. So far the project has moved 135 of the 9,900 pairs to the new nesting site at Crump Lake, enough for the linked article to describe it as a success. It is too early, though, to judge how well the project will work. One problem is that we do not yet know how well terns will adapt to the new nesting locations. Terns bred there in the past, but local conditions such as food availability and nest predation may have changed since then. The linked article mentions gulls as a potential nest predator at the Crump Lake site, where they are more numerous than they are at the Columbia River colony.

A second potential problem is suggested by the first quoted paragraph above. The current situation at the mouth of the Columbia, with a large colony of terns preying on two endangered populations, is largely man made. Habitat changes elsewhere caused nesting terns to relocate to the Columbia River. The fish populations' decline is human-caused, as well; dams and other obstacles block many waterways that formerly served for spawning. Relocating terns could have unpredictable effects on prey populations at the new sites. If a local prey population crashes, another relocation project will be required.

Osprey Webcam in Delaware

Via the Caroline County Bird Club, I just came across this live osprey webcam from Cape Henlopen State Park in Delaware. Unlike many other online raptor webcams, this webcam streams live video, so that you can hear sounds and watch the birds move around. The parent osprey is calling as I write this. Viewing the video requires a Quicktime plugin.


Also: During the feeding session, one nestling was definitely getting a lot more fish than the others.

Court Will Not Hear Border Wall Challenge

Today the U.S. Supreme Court refused to hear a constitutional challenge to the border wall's environmental waivers.

Without comment, the justices refused to consider pleas that Homeland Security Secretary Michael Chertoff overstepped his constitutional authority by waiving laws and regulations in order to expedite construction of 670 miles of fencing along the U.S.-Mexico border.

Chertoff, invoking authority that he said he was granted by the REAL ID Act of 2005, has waived more than 30 laws in the administration's goal to complete the fencing by Dec. 31. The cabinet secretary has told Congress "it would be impossible" to meet the deadline without invoking the waivers.

The case in question before the high court focused on a two-mile section of fencing in the San Pedro Riparian National Conservation Area near Naco, Ariz. A broader challenge to Chertoff's waiver authority has been filed a federal court in El Paso, but fence opponents acknowledged that the Supreme Court decision was a stunning setback in their efforts to block construction.

It is unclear to me whether wall opponents have any other legal recourse at this point. Moral suasion does not seem to work with this administration, and a legislative remedy seems unlikely. So, in the absence of further obstacles, it seems that construction will go forward.

I have written before about the dangers the wall poses to endangered wildlife along the U.S.-Mexico border, including the Sabal Palm Audubon Center. No Border Wall has more on the environmental impact.

Ducks in a Row

These are duck specimens in the natural history display at the 1876 Centennial Exposition in Philadelphia. It is part of several large collections (containing hundreds of photographs) recently uploaded to Flickr by the Smithsonian Institution. Many photographs (such as this collection of cyanotypes) illustrate objects from the collections. Others document life around D.C., such as this aerial view from 1932 and this three-wheeled postal motorcycle. And then there are many portraits of artists and scientists, such as Charles Darwin and Asher Durand.

Since these are federal government collections, and many date to the 19th century, the images in the photostream are in the public domain. So this could be a good resource for bloggers looking for images.

Google Ghost

Google Maps occasionally produces strange results in places where multiple images are stitched together. One such phantom is in the northern Chesapeake Bay: something that looks like a green mask.

According to Google's engineers, it was unplanned and not part of the original photographs.

Chikai Ohazama, who oversees mapmaking operations at the Internet giant, said the skull never actually appeared in the water. Instead, he said, it was created by accident on a computer as Google technicians digitally combined two satellite photos of the same area.

"I'm sure they just missed" the skull shape that was produced in the combined image, Ohazama said.

Ohazama said that the image had probably been up for a year at least and that there were no plans to remove it. He said there was no evidence that anyone at Google had drawn the skull on purpose.

"We try to reflect reality as much as possible," he said. "That couldn't happen. Or, it shouldn't happen."

I have not seen any of the other odd things mentioned in the article, but I have noticed some places where seams between images do not match up exactly. In the example below (from Google Earth), two photographs were taken from slightly different perspectives, so that the two sides of a bridge appear to trail off into the water.

Baby Birds!

There has been a lot of breeding activity in my neighborhood lately. I can see the location of a catbird nest from my bedroom window. (I cannot see the nest itself, just the bush where the nest is located, and the constant activity of the the male and female flying in and out of the bush.) There are also a lot of fledglings begging for food. The ones I have noticed most are common grackles, but other common species are represented, too. Here are a few photos of them, courtesy of the Birdcam.

Juvenile grackle at a birdbath

Juvenile robin lifting a leaf

Juvenile robin bathing

There are more recent images at my Flickr account.

Loose Feathers #154

Brown Pelican / Photo by Gary M. Stolz (USFWS)

Bird news

• Maine Audubon has identified 22 potential Important Bird Areas within the state. Initial work has focused on wetland sites in southern and central Maine, as well as coastal areas, to preserve habitat for piping plover, saltmarsh sharp-tailed sparrow, and rusty blackbird.
• A waterfowl survey in North Dakota estimated that there are 3.4 million ducks (of all species) in the state. That was the 13th highest result since the survey began in 1948. Canvasbacks and scaup were especially plentiful. Unfortunately they may have trouble finding places to breed, since the number of wetland sites is down 70% since 2007, the 10th lowest total in the history of the survey. The low number of wetland sites is due to a combination of dry conditions and land being taken out of the Conservation Reserve Program.
• In sage grouse news, the Bureau of Land Management has agreed to protect "core population areas" that Wyoming has designated. The protected land would total between 200,000 and 400,000 acres. The BLM still insists on allowing oil and gas wells in or around these areas, so it is hard to predict how protected they will really be. Meanwhile, it looks like the Wyoming sage grouse population has declined over the past year. Also, a new USGS assessment documents the species's range and habitat needs.
  
• The American Bird Conservancy announced new land purchases to protect endangered birds in five South American countries. The new reserves will protect both South American resident species and Neotropical migrants, including cerulean warblers. The image at right is a flock of El Oro parakeets, at the Buenaventura Reserve in Ecuador.
  
• Cyclone Nargis destroyed bird habitat in Myanmar's Irraddy delta. The area is important for painted storks and bronze-winged jacanas, among other waterbird species.
• Floods have also washed out 1600 nests of birds in the Ouse Washes. The nests included 12 pairs of rare garganeys.
  
• Florida wants people to stop feeding brown pelicans.
• The oldest documented wild bald eagle in the Midwest was found dead at the age of 31. The bird was hatched and banded in 1977 at a nest in Ottawa National Forest.
• Here is a video about hummingbirds.
• A white stork showed up at a maternity ward in Scotland.
• Audubon Alaska produced a birding map for Anchorage.
  
• The Earth Conservation Corps is trying to raise environmental awareness among young District residents by running educational events with live wild birds at Nationals Park during baseball games.
• A wildlife rehab center helps orphaned wild birds learn to sing by playing CDs of the dawn chorus next to their cages.
  

Birds in the blogosphere

• City Birder: Interesting paint job
  
• BES Group: Blue-eared Barbet and its black gular sac
• Urban Hawks: Perspective
• Rob's Idaho Perspective: The Null Survey
  
• Mon@rch: Killfawns
  
• Drinking Bird: Burn Baby Burn
• Sortie Ornitho: Avocette élégante juvénile
  

Environmental news

• The Arctic Sea could have ice-free summers by 2013.
• A continued rise in greenhouse gas emissions could bring more extreme weather to North America. The southwestern U.S. will face more intense droughts, while other parts of the country will face greater rainfall. An increase in hurricane activity seems likely as well, though the evidence for that is less conclusive.
• Oceans are warming 50% faster than expected.
• This year's dead zone in the Gulf of Mexico is likely to be 10,000 square miles – well above the 20-year average.
  
• Gristmill: The politics of clean energy
• The Island of Doubt: Heads stuck in the sands
• NRDC Switchboard: Whales and Oil
• A rare wildflower was found in Sussex County, NJ.
  

Carnivals and newsletters

• Carnival of Cities
• Just Write
• Friday Ark #196
  
• Birds in the News #135
  

Top 10 New Species

The International Institute for Species Exploration recently published a list of the top 10 species discovered in 2007. National Geographic has posted a gallery with photographs of all ten. No birds are represented, but the photos are still interesting because they show the tremendous amount of biodiversity that is still being discovered. The photo above is a Shocking Pink Millipede (Desmoxytes purpurosea), found in Thailand.

Three Years

I neglected to mention yesterday that it was this blog's blogoversary, though some readers noticed the marker at the bottom of the page. Bird blogging has changed tremendously in the last three years. When I wrote my first post, I knew of only a handful of other bird blogs; now there are hundreds. (Mike Bergin's Nature Blog Network lists 344 blogs, and I am sure that there are others out there.) There are also more professional birders with blogs than three years ago. Some blogs that I really enjoyed have since stopped publishing, or disappeared entirely; other new sites have taken their places.

This blog has also changed its focus. I originally conceived it as a way to write more expansively about my field birding. Since then bird and environmental news has gradually taken over and is now the main topic that I write about. Within the last year, the blog also survived a change in my location, from DC to New Jersey.

Here are a few highlights from the last year:

• Bald Eagles No Longer Endangered
• Shorebirds at Jamaica Bay
• Bar-tailed Godwits on the Move
• Warblers at Noon; Rails at Dusk
• Bird Claws and Evolution
• 1 in 1,000,000
• Counting on the Canal
• A Rare Bird by Subway
  

New Predators Lead to Changes in Nesting Behavior

Invasive species – plants, animals, or others – pose major problems for native species. Some of the worst cases of invasion come from Pacific islands where many birds that evolved without predators have become extinct or endangered due to introduced mammals. A recent study of bellbirds in New Zealand provides a counter example of birds changing their behavior to cope with an introduced predator.

The study focused on the New Zealand bellbird (Anthornis melanura), an endemic species that was exposed to introduced mammalian predators within the last 200 years. It compared nesting behavior at four types of nests:

1. Mainland bellbird nests with introduced predators present
2. Mainland bellbird nests with introduced predators removed
3. Island bellbird nests with no introduced predators
4. Tasmanian honeyeater nests with native predators
   

Bellbirds adjusted their behavior to the presence of exotic predators by reducing the number of parental visits to the nests and increasing the amounts of time spent on the nest and away from the nest. Parents at both mainland sites fed their chicks far less often than parents at the island site, but more often the Tasmanian birds. Fewer visits means that a nest location is less obvious to nest predators, which will have fewer chances to track a parent to the nest. (I wonder, though, if the lower fledge rate of mainland chicks – 29%/39% mainland vs. 65% island – is partly a result of fewer feeding visits.)

The number of parental visits to the nest per hour to feed nestlings for bellbirds on Aorangi Island, where exotic predators were never introduced, for bellbirds in Waiman Bush, where exotic predators were removed, for bellbirds in Kowhai Bush, where all exotic predators are present, and for honeyeaters in Tasmania, which evolved with a range of native mammalian predators. (Click to enlarge)

This study gives some hope that other native island birds can adapt relatively quickly to the presence of new predators. These particular adaptations are specifically suitable for woodland birds, whose nests can be easily hidden. Seabird colonies and flightless birds face greater challenges in protecting their nests from predators. The best policy is still to prevent the spread of harmful invasive species or remove them where possible.

Oregon Fish Tag Found in New Zealand

Somehow an electronic tag from a steelhead salmon in Oregon ended up in New Zealand, possibly carried by a sooty shearwater.

The tiny device was noticed by Maori hunter Dale Whaitiri on Mokonui Island, one of the Titi Islands (New Zealand). Shearwaters nest in burrows among tree roots on the island, and are known locally as Titi or Muttonbirds. The tag was recorded two years earlier as young steelhead smolts were passing the Bonneville Dam, on the Columbia River – 10,170 km from Mokonui!

Scientists think that the fish may have been eaten by a shearwater that was scavenging fishery wastes behind a processing vessel in the north pacific. Steelhead Salmon are not a commercial species, but they are sometimes accidentally taken as by-catch. Alternatively, the fish may have been predated as it passed below one of the large shearwater flocks that frequent the mouth of the Columbia River.

This seems quite likely, since shearwaters undertake amazing migrations. Every year, they complete a round trip of 39,000 miles, between their breeding grounds in New Zealand and wintering area in the northern Pacific. They may spend more time wandering than confined to a particular location.

Review: Smithsonian Field Guide to the Birds of North America

For many years, if you wished to use a photographic guide for birding, your only choices were the National Audubon Society field guides for Eastern and Western North America. These guides were deficient in many respects, not least of which was the organization of plates by color rather than taxonomy. In the last decade the situation has changed, with the publication of more useful photographic field guides by Donald and Lillian Stokes, Kenn Kaufman, and the National Wildlife Federation.* The latest entrant into the photographic mix is Ted Floyd's Smithsonian Field Guide to the Birds of North America.

The Smithsonian Guide includes over 750 species of birds that occur regularly in North America. Species are in roughly taxonomic sequence, following the AOU checklist, with a one-page introduction to each bird order or family. There are generally two species per page, with a few species getting full page treatment. A brief introduction includes standard information about plumage and molt, as well as an overview of habitat types and common behaviors.

Floyd wants birders to follow a "holistic" approach to bird identification. In other words, one should not only look for field marks, but also consider habitat, behavior, vocalizations, and other aspects of a bird's natural history. To that end, each species account is packed with information about habitats, behaviors, and plumage variations, as well as how a bird's habits influence morphology. The text also describes each species's typical song and calls; a DVD inside the back cover includes vocalizations for 138 bird species. (For samples, visit the book's website.) Of course, each account is illustrated with 2-5 very good photographs and a range map. I do wish that more of the species accounts included a photograph of the bird in flight since flight photographs provide useful information. However, the text and photographs provide adequate detail to identify most birds.

If you prefer identifying birds from photographs rather than painted plates, this guide would make an excellent choice. Species accounts include jargon that might intimidate beginners, so the guide seems most suitable for intermediate and advanced birders. Beginning birders may still be interested in the DVD of bird vocalizations, which can be downloaded onto any digital music player. The book's heft** makes it unsuitable as a pocket guide, but it would fit nicely into a backpack. For my own birding, I plan to stick with the eastern edition of the Sibley Guide since I prefer illustrations to photographs. However, I can see myself making frequent reference to the Smithsonian Guide to help with identifications or for more information about a species.

* For a direct comparison of the five photographic guides mentioned here, visit The Birder's Library. (Update: See also Rob Fergus's Evolution of the Bird Photo Field Guide. The most thorough review of the Smithsonian Guide so far is at Woodcreeper.)

** The Smithsonian Guide is only slightly smaller and lighter than the full-size Sibley Guide.

---

Ted Floyd, Smithsonian Field Guide to the Birds of North America. New York: HarperCollins, 2008. Pp. viii, 512; maps, color photographs, figures, references, glossary, checklist, index, DVD. $24.95 softcover.

Website: smithsonianbirdsofnorthamerica.com

Most Common Birds in Middlesex County

As I mentioned in the last Loose Feathers, Cornell Lab of Ornithology is in the midst of redesigning its website and is looking for user input. One of the most commonly requested features is an automated field guide page, where a user could enter an unknown bird's field marks and receive a list of possible species. The first version of this automated identification guide would consist of 120 species, with more to be included in future versions. For the latest discussion question, the design committee wants to know which 120 species to include.

I decided to post my answer here. Such a limited set of identification choices should aim to cover the most common birds that people are likely to see. The following is a list of the 40 most commonly reported bird species of Middlesex County, New Jersey, according to eBird data. All of them have a solid case for inclusion because all are very common and very widespread outside of this area.

1. Mourning Dove
2. Northern Cardinal
3. Canada Goose
4. American Robin
5. House Sparrow
6. American Goldfinch
7. European Starling
8. House Finch
9. Blue Jay
10. Downy Woodpecker
11. Common Grackle
12. Song Sparrow
13. Dark-eyed Junco
14. White-throated Sparrow
15. American Crow
16. Red-bellied Woodpecker
17. Tufted Titmouse
18. Black-capped Chickadee
19. Mallard
20. Northern Mockingbird
21. Ring-billed Gull
22. Red-winged Blackbird
23. White-breasted Nuthatch
24. Gray Catbird
25. Herring Gull
26. Carolina Wren
27. Northern Flicker
28. Great Black-backed Gull
29. Red-tailed Hawk
30. Killdeer
31. Great Blue Heron
32. Brown-headed Cowbird
33. Rock Pigeon
34. Double-crested Cormorant
35. Carolina Chickadee
36. Turkey Vulture
37. Barn Swallow
38. Great Egret
39. Tree Swallow
40. House Wren

Combining top 40 lists from all over the continent ought to fill out the top 120 list easily.

Flooding Bird Nests

The massive floods in Iowa this spring are forcing animals in their path to move to higher ground. In particular, flooding has disrupted nesting for any bird species that breed along riverbanks.

What's of particular concern is how rare species of birds, reptiles and amphibians will fare, he said.

Also, there are many bird species in Iowa that winter in Central and South America, returning to Iowa in late May or early June to nest near rivers and streams, Pease said. Those birds usually nest once a year. If their nests have been swept away by the floods, "then that's it for the year," he said.

"If we get too many years in a row of this, we'll certainly see population declines," Pease said.

Harr said wildlife is resilient, and many songbirds will renest two or three times this year, and pheasants may be able to renest later this summer.

But the floods will probably take most of the nests of sandhill cranes this year, Harr said. The birds, which nest just once a year, nest along some of the state's eastern rivers.

If spring conditions are good next year, it's expected that the birds will return to nest, Harr said.

The loss of an entire year's worth of nestlings is troubling but probably will not depress the bird population too much. What is more concerning is that these types of hundred-year events could happen with more frequency. One of the many predicted consequences for climate change is an increase in the frequency and intensity of heavy storms such as the ones currently flooding the Midwest. With these types of events happening more often, we would probably start to see substantial losses in riparian bird populations.

Wilkins Ice Shelf Just Got Smaller

Starting on May 30, a large chunk broke off of the Wilkins Ice Shelf on the Antarctic Peninsula even though it is winter in Antarctica.

Wilkins Ice Shelf, a broad plate of floating ice south of South America on the Antarctic Peninsula, is connected to two islands, Charcot and Latady. In February 2008, an area of about 400 km² broke off from the ice shelf, narrowing the connection down to a 6 km strip; this latest event in May has further reduced the strip to just 2.7 km.

This animation, comprised of images acquired by Envisat’s Advanced Synthetic Aperture Radar (ASAR) between 30 May and 9 June, highlights the rapidly dwindling strip of ice that is protecting thousands of kilometres of the ice shelf from further break-up.

According to Dr Matthias Braun from the Center for Remote Sensing of Land Surfaces, Bonn University, and Dr Angelika Humbert from the Institute of Geophysics, Münster University, who have been investigating the dynamics of Wilkins Ice Shelf for months, this break-up has not yet finished.

"The remaining plate has an arched fracture at its narrowest position, making it very likely that the connection will break completely in the coming days," Braun and Humbert said.

Wilkins is one of seven Antarctic ice shelves that have either collapsed or lost much of their volume in the past 20 years. The recent collapses are all linked to climate change. The Antarctic Peninsula's average yearly temperature has risen by 2.5°C over the past 50 years. Warming there is proceeding at a fast pace compared to the rest of the world, which has warmed 0.6°C over the past 100 years. With continued warming, the remaining ice shelves may well disappear.

You can find an animation of the most recent breakup at the link above and a more technical explanation of ice shelf breakup at RealClimate.

Loose Feathers #153

Baird's Sandpiper on Nest / USFWS Photo

News about birds and birding

• Increasing the amount of red on a male barn swallow's breast will increase the bird's testosterone. Biologists suspect the hormonal change is a result of increased attention from females and hostility from rival males.
• Europe has had difficulty producing a common management strategy for its great cormorant population because of disagreement among the various stakeholders. Fishermen have been pushing for cormorant culls because they believe that cormorants are eating all the fish.
  
• Two recent announcements from the Cornell: First, the CLO website is getting a new design, and the lab wants input from users. Second, eBird has a lot of geographic gaps; birders with sightings from those areas can help make the database more useful.
• An oil spill near Uruguay has killed at least 100 penguins, with more dead and injured birds washing ashore every day.
• A new genetic map of bird species in the UK indicates that related species tend to decline simultaneously.
• Three California condors were released back into the wild; three others are still being treated for lead poisoning.
• Cleanup and reuse of polluted cropland in California may put thousands of shorebirds at risk.
• Senators Dole and Burr want federal legislation to restore off-road vehicle access to Cape Hatteras National Seashore; currently access is blocked to protect nesting shorebirds.
  
• Floods in the UK wiped out hundreds of lapwing, redshank, and snipe nests.
  
• Yellow wagtails nest on the ground twice per year. For the first nest, they prefer wheat crops; for the second they prefer potato crops.
• Scientists have found a new nightjar species in Nepal. Sykes's Nightjar (Caprimulgus mahrattensis) was found near the Koshi River and also breeds in Pakistan and northwestern India.
  
• Teachers at an elementary incorporated a killdeer nest on campus into lessons for students about birds and conservation.
• Wildlife police blotter: a boat owner knocked down 30 nests and killed 186 "mud swallows"; 31 birds were killed when teenagers released dogs on them; a man was charged for shooting ducks with a pellet gun; someone shot an arrow through a goose.
  
• A Long Island woman was quarantined because she was covered with bird mites. The mites spread into her home from a bird nest in her bathroom vent.
  

Birds in the blogosphere

• Tetrapod Zoology: 2007: a good year for terror birds and mega-ducks
• 10,000 Birds: The REAL red, red Robin
• Behind the Bins: The Importance of Sparrows
• Birdfreak: Murphy’s Laws of Birding
• Greatest Auk: Billions and Billions
• Drawing the Motmot: Bobolink Babylon
• OC Birding: Note-taking
• Tails of Birding: Colorful Blackbirds - the Baltimore Oriole
  

Environmental news

• Permafrost in eastern Siberia contains about 500 Gigatons of frozen carbon deposits; if the permafrost thaws, the carbon would start to be released into the atmosphere, eventually reaching a rate of several trillion pounds per year. Frozen carbon deposits near the poles are one of many potential feedback mechanisms that could warm the climate higher and faster than current predictions.
• The Greenland Ice Sheet is melting faster than previously calculated and freshwater runoff will double by 2100.
  
• A new atlas tracks recent changes to Africa's landscape. Among other things, it shows a 50% decrease in glaciers at Mount Kilimanjaro and the Rwenzori mountains.
• A major challenge for conserving global biodiversity is that conservationists lack data for areas undergoing the greatest biodiversity loss.
  
• Enviroblog: Lead: Bad for brains, bad for society
  

Carnivals and newsletters

• I and the Bird #77
  
• Tangled Bank #107
• Birds in the News #134
  
• Linnaeus' Legacy #8
  

I and the Bird

I and the Bird #77 is online at Great Auk – or Greatest Auk?

Red Knots Not Eating Enough

As a follow-up to last night's post, this year's banding sessions have found that red knots are not gaining as much weight as usual. I suspect that part of the problem was that a large storm swept through the bay right as horseshoe crabs started spawning. However, a strong weather event would not have such an impact in the situation were not already dire.

Biologists have determined that the knots need a density of about 50,000 pearlescent crab eggs per square meter of beach to feed efficiently.

But this year, a May storm swept the eggs from the beaches. Afterward, the crab spawn, exquisitely timed to the arrival of the birds, slowed.

Counts showed an average density of fewer than 500 eggs per square meter.

In 1997, about 80 percent of the birds leaving the bay had bulked up to a needed weight of about 180 grams, or six ounces.

This year, based on data obtained from birds that were captured in nets, only 15 percent - the lowest proportion biologists have yet seen - gained sufficient weight.

Next winter's surveys in South America will tell what effects this will have on the red knot population. I fear that this will bring the bird closer to the extinction – and very soon.

Red Knot Banding

American Road Journal visited Delaware Bay last year for red knot migration. This video shows the stages of the red knot banding process – from netting to release.

(Via JerseyBirds)

Different Tactics, Same Result for Climate Change Skeptics

As I wrote on Friday, the Lieberman-Warner Climate Security Act fell to a filibuster. Some press reports indicate that terms of the debate are changing. Instead of denying the science outright, opponents of greenhouse gas reductions accept the science and now attack reduction plans based on the estimated cost. I think that we ought to be skeptical that changes in tactics mark a real improvement.

First of all, I am not sure that this claim is true. One of the highest-profile opponents of reductions, Senator James Inhofe (R-OK), is just as much of a denialist now as he always has been. The minority page of the Senate Environment and Public Works Committee posted a recent story claiming that the climate is cooling and still has prominent links to Inhofe's "Skeptic’s Guide to Debunking Global Warming Alarmism." In the debate over the Lieberman-Warner bill, he claimed that everything in An Inconvenient Truth was refuted by the IPCC.

Second, offering cost-based objections is still obstructionism. A bill blocked on the basis of outright denialism gives the same outcome as a bill blocked on the basis of cost. Cost-based objections exist at one end of a spectrum of denial and delaying tactics. Depending on which argument is most convenient, obstructionists will deny that the climate is warming, or that warming is caused by humans, or that the effects will be harmful, or that it is possible to cut emissions without wrecking the economy. (These all have many variants and sometimes occur simultaneously.) Since the outcomes are the same, the specific tactics do not matter to heavy-carbon industries and their supporters in the Senate.

Climate science does not only include analysis of how greenhouse gases will change the climate. It also predicts the effects of warming temperatures – on sea levels, on our food supply, on human health, on ecosystems and wildlife, to name a few. All of these effects impose very real economic costs, which ought to be part of any cost-benefit arguments in the debate over what actions to take. Focusing only on the costs of reducing emissions, while ignoring the costs of doing nothing, is at best myopic and at worst implicitly denies the science underlying the calls for action.