Red Knot Continues to Decline

Red knots have continued to decline this spring. Migration counts along the Delaware Bay found only 12,300 knots, compared to 15,000 last year. Two decades ago, the population was much higher, in the hundreds of thousands.

A Red Knot Flaps Its Wings / Photo by Tim_Shaffer (Reuters)

Red knots are one of several species that migrate prodigious distances every spring and fall. Knots breed in the Arctic and spend the winter in southern Argentina and Chile. Their 9,000 mile migration requires that they have adequate food supplies along the way. A key stop during spring migration is the Delaware Bay, where hungry shorebirds regain their weight by feasting on the eggs of horseshoe crabs, which come ashore to lay their eggs just as the knots arrive. Over the last two decades, the number of horseshoe crabs has declined due to harvesting. Knots have declined along with the crabs.

States around the Delaware Bay recently imposed moratoriums and other restrictions on harvesting horseshoe crabs. The good news is that these policies appear to be working to some extent; captured shorebirds this year were at a healthy weight. Unfortunately, it will take several years for the horseshoe crab population to rebound enough for the red knot population to increase. Whether the red knots can last that long is an open question.

Because red knots have declined so rapidly, scientists and conservation groups have sought to have red knots protected under the Endangered Species Act. As with other declining species over the past six years, petitions filed with the US Fish and Wildlife Service so far have been ignored or denied. Federal listing would be helpful since it could then coordinate conservation actions among the various states whose policies affect red knots' survival as a species. Not all states are equally committed to protecting red knots; for example, Virginia turned down a horseshoe crab harvest moratorium, and Delaware was slow to impose one.

I have been lucky enough to see red knots in Delaware, though I missed them this year.

You can read more about monitoring red knots at The Shore Bird Project.

(news link via squeaks)

Update: Next week (June 11-14) there will be an International Symposium on the Science and Conservation of Horseshoe Crabs held on Long Island. (Thanks, Julie!)

Brightly-colored Birds

On Saturday I helped lead a DC Audubon field trip to Little Bennett Regional Park in Montgomery County. (Go there for photos from Saturday.) Little Bennett covers 3700 acres of bottomland forest and old fields in various stages of succession. The habitats preserved in the park have become more valuable in the light of recent changes; land around the park that was open space until very recently is now occupied by subdivisions. We visited Little Bennett in search of breeding birds that can be hard to find in the DC area. We started out at the Kingsley Trail, since that winds through a mix of habitats, and then moved on to a spot on the north end of the park. About a dozen participants attended, which is a good size for a field trip.

Prairie Warbler / Photo by Steve Maslowski (USFWS)

We heard and saw several prairie warblers along the course of the Kingsley Trail and Purdum Trail, starting with a bird singing near the parking lot. Later in the morning, we had a great look at a male as it foraged, popping in and out of some low shrubs. Along the Kingsley Trail, we had eastern bluebird, white-eyed vireo, yellow warbler, black-and-white warbler, Louisiana waterthrush, scarlet tanager, and Baltimore oriole. A northern parula was singing near the schoolhouse, which hosted an eastern phoebe nest in its cupola. When we walked uphill to the Purdum Trail campground, we found cedar waxwing, pine warbler, ovenbird, and field sparrow near the top.

The pine warbler gave a lesson in the trickiness of distinguishing trills. As I looked at a pine warbler through my binoculars, I could hear a trill, which I assumed was another male pine warbler. Soon enough, however, someone else spotted the real source of the song - a chipping sparrow.

Kentucky Warbler / Photo by Steve Maslowski (USFWS)

At the north end of the park, we hoped to find a Kentucky warbler that had been reported along the closed section of Hyattstown Mill Road. As we walked down the road, we had the opportunity to watch a singing Louisiana waterthrush and a yellow-throated vireo. Otherwise the road was fairly quiet. Finally, my co-leader spotted a Kentucky warbler, and it stayed in the open long enough for most of the group to get at least a short look. Before we left, we had a second, better look at a Kentucky warbler. This bird stayed at eye level and showed off its spectacular colors. As we returned to the cars, a bright red bird flashed across the road. My first thought was cardinal, but something did not seem right about the identification - the red was too bright, the red tail far too short. After conferring amongst ourselves and consulting our field guides, we concluded that the bird was a summer tanager, a southern species that breeds in a few locations around the DC area.

Scarlet Tanager / Photo by Steve Maslowski (USFWS)

One of the paradoxes of birding is that some of the most brightly-colored birds are also the hardest to find. Male scarlet and summer tanagers, for example, are a brilliant scarlet red. It is hard to find a brighter red among North American birds. Even cardinals have trouble competing against the tanagers. Looking at a field guide illustration, one might think that tanagers would be easy to spot, like cardinals. Many warblers are also brightly colored, at least in breeding plumage.

The reality is that the bright colors and bold patterns of forest birds can be easily missed. In the case of warblers, like a prairie or Kentucky warbler, those bold patterns help to break up a bird's shape, while the typically olive upperparts and white or yellow underparts tend to blend into the foliage. Tanagers present a special problem because they spend most of their time in the upper canopy. At the tops of trees, their bright colors sometimes work against a bird watcher because they disappear in the patterns of dappled light.

On this occasion, we would not get a second look at the summer tanager, though we could hear the bird singing nearby. Brightly-colored birds may not always be easy to spot, but they offer a high reward to those that can find them. On Saturday we were rewarded with stunning looks at great birds.

Satellite Climate Sensors Reduced

Last week, President Bush appeared to yield some ground on the issue of global warming. He proposed a series of meetings among the major producers of greenhouse gases to discuss long-term plans to reduce emissions. Some interpreted his intervention as an attempt to delay the implementation of existing climate goals, but it came as a rare acknowledgment that a problem even exists.

This week, it seems that things are back to normal. The administration plans to reduce the ability of scientists to monitor the status of the Earth's climate by satellite. Data from satellites has been a major tool for assessing the scope of climate change.

A confidential report to the White House, obtained by The Associated Press, warns that U.S. scientists will soon lose much of their ability to monitor warming from space using a costly and problem-plagued satellite initiative begun more than a decade ago.

Because of technology glitches and a near-doubling in the original $6.5 billion cost, the Defense Department has decided to downsize and launch four satellites paired into two orbits, instead of six satellites and three orbits.

The satellites were intended to gather weather and climate data, replacing existing satellites as they come to the end of their useful lifetimes beginning in the next couple of years.

The reduced system of four satellites will now focus on weather forecasting. Most of the climate instruments needed to collect more precise data over long periods are being eliminated.

Instead, the Pentagon and two partners — the National Oceanic and Atmospheric Administration and NASA — will rely on European satellites for most of the climate data.

"Unfortunately, the recent loss of climate sensors ... places the overall climate program in serious jeopardy," NOAA and NASA scientists told the White House in the Dec. 11 report obtained by the AP.

They said they will face major gaps in data that can be collected only from satellites about ice caps and sheets, surface levels of seas and lakes, sizes of glaciers, surface radiation, water vapor, snow cover and atmospheric carbon dioxide.

[...]

NASA and NOAA agreed in April to restore sensors that will enable the satellites to map ozone. NOAA Administrator Conrad Lautenbacher said that would give scientists a better idea of the content and distribution of atmospheric gases.

But seven other separate climate sensors are still being eliminated or substantially downgraded by lower-quality equipment to save money, according to the report to the White House. Most of the satellites, which were scheduled to launch starting next year, have been delayed to between 2013 and 2026.

In this case, it is hard to tell whether the fault lies with planning and execution or with political interference. Given the recent record on climate matters, the latter would not surprise me at all. The House Committee on Science and Technology will be holding hearings on the satellites, so we should find out more in the near future.

New Rules for Bald Eagles

The U.S. Fish and Wildlife Service has clarified the regulations that would protect bald eagles if they lose protection under the Endangered Species Act. In recent decades bald eagles have rebounded from a low of 417 pairs to over 9,800 today. The steady increase in the eagle population has led to pressure to declare eagles recovered. Last year a court ruled that the Service must decide whether bald eagles will remain on the endangered species list by June 29, 2007.

If bald eagles are de-listed, they would fall under the protection of other statutes, the most important of which is the Bald and Golden Eagle Protection Act of 1940 (pdf). That law forbids the taking, possession, transportation, selling, and purchasing of eagles, parts of eagles, nests, or eggs. "Take" is defined in the law as "pursue, shoot, shoot at, poison, wound, kill, capture, trap, collect, molest or disturb."

A key point of disagreement was how best to interpret "disturb" under the Eagle Protection Act. Last year, a draft regulation was strongly criticized for defining "disturb" too narrowly. A major weakness of the 1940 law is that it does not include explicit habitat protections, so there was concern that nest and roost sites be included in the new regulations. After a public comment period and further consultation, the Fish and Wildlife Service has released a new definition (pdf) of "disturb":

Disturb means to agitate or bother a bald or golden eagle to a degree that causes, or is likely to cause, based on the best scientific information available, 1) injury to an eagle, 2) a decrease in its productivity, by substantially interfering with normal breeding, feeding, or sheltering behavior, or 3) nest abandonment, by substantially interfering with normal breeding, feeding, or sheltering behavior.

In addition to the new definition of "disturb," the U.S. Fish and Wildlife Service has proposed a new rule allowing limited takes of bald and golden eagles under a permit program (pdf). Takes would be permissible under some circumstances when they are incidental to other legal activities, or when the location of an eagle nest poses a hazard to humans or eagles (like near an airport runway). The permit system would function in a manner similar to takes under the Endangered Species Act, and would give the Fish and Wildlife Service a chance to work with landowners to minimize impact. A public comment period on the permit program will open on June 5.

More information about the new regulations can be found at the U.S. Fish and Wildlife Service website on bald eagles.

Loose Feathers #101

Yellow Warbler / Photo by Donna Dewhurst (USFWS)

News and links about birds, birding, and the environment

• An eaglet in County Donegal is the first wild golden eagle chick to hatch in Ireland since 1910.
• National Park Service is planning improvements to two major DC-area parks.
• The Dartford warbler, down to 11 pairs in 1963, is repopulating its former range. As of the latest survey, there are now about 3,200 pairs. The RSPB attributes the recovery to habitat protection.
• The administrator of NASA does not think that global warming is a problem, even though members of his own agency have provided much of the evidence for it.
• Bird mortality and wind power are in the news again this week, with a possible project near Point Pelee and a wind farm in northern New York that is killing hundreds of songbirds. Meanwhile, Rendell wants to open Pennsylvania's state parks and forests to wind development.
  
• Birds in the tropics live a more leisurely life than closely-related birds in northern regions. Researchers measured their life styles in terms of energy use, life span, and growth rates. Neotropical migrants used more energy than resident tropic birds, but less than resident northern birds.
• Some birds follow hordes of army ants to catch the insects that try to escape from the ants.
• Maryland is attempting to block a 4,300-home development project in northern Allegany County. The planned development is close to Green Ridge State Forest, which provides important breeding habitat for several species of birds. The plan appears to be supported by local officials but opposed by a coalition of local citizens.
• Also in development news, there is a dispute over a 1,063-home project near Virginia Beach, which would effect a wetland.
• The U.S. House approved a defense appropriations bill that excluded funding for the planned airfield near Pocosin Lakes NWR in North Carolina. The House urged the Navy to use a different site.
• Residents in the Chicago area are worried about the effects of new sporting venues for the 2016 Olympics on local wildlife preserves. One potential site is home to sandhill cranes and yellow-headed blackbirds.
• Bird festivals are coming soon to Sussex County, New Jersey, and Canaan Valley, West Virginia.
  

Birds in the blogosphere

• Thomasburg Walks: I'll Sing What I Want to Sing
• Birdchaser and Birdchick argue over the appeal of bird-related kitsch. I'm mostly with Birdchick, though I think that the Audubon clock (or Birdchaser's proposed variant) would drive me nuts.
• BES Group: Encounters with the Great Argus
• Mike's Birding and Digiscoping Blog: Birder, Biker, Birker
• Belgrade 2.0: Birdwatching in Serbia
• Palemaleirregulars: Who Says Birds Don't Have Personality?
  

Carnivals and link digests

• Festival of the Trees #12
  
• Friday Ark #141
• I and the Bird #50
• Birds in the News #85