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From the Washington Post's Tom Toles.
Update: One reason to oppose coal-to-liquid proposals is that coal contains more mercury than crude oil, making it a dubious alternative energy choice. Other reasons are listed in this editorial. The Senate today rejected two amendments that would have added subsidies for liquid coal to the energy bill.
The wood thrush has lost 43 percent of its population over the past 40 years, making it a species of conservation concern. As with other species in decline, the main culprit seems to be the loss and fragmentation of woodland habitats, largely due to development. Ongoing research at the University of Delaware compares the breeding success of wood thrushes at a university woodland preserve and in a nearby neighborhood.
Roth discovered that loss of habitat hasn't deterred the remaining wood thrushes from summering in Delaware. However, many must try to breed in less than desirable conditions; in the 1980s, Roth studied a sizable population of wood thrushes in the wooded Newark neighborhood of Arbour Park. These birds had the usual two to three nests with three to four eggs per year, but raised significantly fewer young than wood thrushes breeding in the UD Woods, located just two miles away. And, unlike the thrushes at the UD Woods, few of the banded adults in Arbour Park returned there the next year, which was more likely an indication of bird dissatisfaction than mortality.
"UD Woods' leaf litter fosters excellent food resources, such as larval and adult insects, earthworms and millipedes. And on the edge of the woods, the birds can forage for berries from spicebush, elderberry and other shrubs," notes Roth. "A suburban neighborhood often doesn't provide such an abundant food supply, much less native trees and shrubs for nesting and shade."
While many nests were lost to predation at Arbour Park, the nests there also were more frequently parasitized by the brown-headed cowbird. It lays its eggs in the nests of wood thrushes and some other song birds, often removing a host's egg for each one laid. The unwitting host incubates the cowbird eggs and feeds the cowbird chicks along with her own. The negative effect on wood thrushes is the loss of eggs.
"Cowbirds are more apt to parasitize nests in small forest fragments, wooded neighborhoods and other edge habitats created by humans than in deep deciduous forests, where the wood thrush thrives," says Roth. "Don't blame the cowbirds; we created the favorable conditions for them."
Over ten years, climate change has caused spring to arrive in the Arctic increasingly earlier than normal. A study in Greenland found that Arctic organisms had adjusted their breeding cycles to match the earlier snowmelt caused by warmer temperatures.
In some cases, flowers are emerging from buds and chicks are hatching a full 30 days sooner than they did in the mid-1990s in response to sharply increased temperatures burning off the winter's snow layer.The results pose some cause for concern, since the variation in adaptation to the new climate conditions may disrupt existing interdependent ecological links.
Birds such as the Sanderling and the Ruddy Turnstone had moved their springtime rituals forward by an average of two weeks by 2005, compared to 1996.
[...]
And while not unexpected, the rate of change is surprising, even in light of the fact that Arctic temperatures are increasing at twice the global average.
Similar studies have noted much more modest changes with respect to plants in Europe (an advancement of 2.5 days per decade) and globally (5.1 days per decade).
"We were particularly surprised to see that the trends were so strong when considering that the entire summer is very short in the High Arctic -- with just three to four months from snowmelt to freeze up at our Zackenberg study site in northeast Greenland," said Hoye, a co-author of the study.
Two of the major factors in climate change are the emission of greenhouse gases, like carbon dioxide, and deforestation in the tropics. The latter is a major concern because tropical forests help absorb carbon dioxide, release their own carbon when burned, and provide important habitat for many bird species. Two authors of an op-ed in today's New York Times argue in favor of a forest preservation program that they call carbon ranching.
Reversing tropical deforestation could be surprisingly cheap and easy because it can be driven by simple economics. Right now, it’s worth more to a logging company or a peasant to convert the rainforest to stumps or soybeans than it is to leave that rainforest intact. One hectare (about 2.5 acres) of forest cleared and converted to ranchland or crops produces a piece of land worth, on average, $200 to $500. But that’s nothing compared to the value of preserving the rainforest as a sponge for carbon dioxide.Carbon offsets have limitations, of course. There is a limit to the amount of carbon that a tree can hold, and forest preservation would be a way of holding steady rather than true reduction of emissions or warming rates. For a program like this to work, it would need to be part of an overall frame work that would include cutting greenhouse gas emissions. Still, it is an interesting proposal, and one that could have positive effects regardless its contribution to slowing climate change.
On European markets, the right to emit one ton of carbon dioxide trades today at more than $20. With each hectare of intact rainforest storing around 500 tons of carbon dioxide, that means that each hectare has a value of $10,000 as carbon dioxide storage, far more than the value of even the most productive tea or soy plantation.
As a recent World Bank report put it, “Farmers are destroying a $10,000 asset to create one worth $200.” To the farmer or agribusiness corporation, of course, that makes perfect sense, because that $10,000 is all theoretical. It can’t put food on the table or deliver dividends to shareholders.
This morning I returned to the National Arboretum to look for breeding birds. I decided to focus my attention on some of the fields and scrubby areas, since I had been neglecting them during the past month. I had some particular target birds in mind. One of them, the blue grosbeak, made its presence known right away. Several males were singing in the small fields behind the columns. I finally caught a look at one as it sang high in one of the oak trees. I love seeing this species at the Arboretum, not only for its bright blue plumage, but also because blue grosbeaks are relatively rare breeders in the District. In the same general area, I could hear the songs of common yellowthroats and indigo buntings.
On my way past the lilac area, I found an acadian flycatcher constructing a nest about ten feet over the road. It seemed a little late for a migrant bird to be starting its breeding, so perhaps this is a second brood. According to The Birder's Handbook, acadian flycatchers will produce two broods; the 1983 edition of the Maryland breeding bird atlas states that they will lay eggs until August 3. This nest was in the early stages, with only an outline made with catkins.
Proceeding to Beech Spring Pond (the larger of the two ponds), I sat down in the grass to see what birds might present themselves. A small flock of cedar waxwings contested the top of a baldcypress on the far side of the pond. I could hear an eastern kingbird in the tree above me while a small group of tufted titmice and carolina chickadees chattered in a tree nearby.
I only walk about a third of the river trail since I was not thrilled about the idea of spending long periods in the sun. The meadow near the south end hosted at least one pair of nesting indigo buntings. They must have a nest very close to the path because the male on one side of the path and the female on the other side - the latter holding a small caterpillar - were both scolding me as I passed. When I moved on from there, I was treated to a pair of great crested flycatchers. These colorful birds are more often heard than seen since their gray backs and ruddy tails blend into the forest environment, and their lemon colored breasts become countershading. In this case, the two birds sat out in the open at eye level for a long time, so it easily made up for all the times I have had only a simply wheeeeep! to mark their presence.
Dragonflies and butterflies have been out and about. As bird songs start to wind down, I will start paying more attention to them. The best areas for both large insects are in the unmown meadows, particularly around the columns and along the river trail. In the lilac area, I saw a little wood-satyr and had my best look ever at an eastern tailed blue. These tiny butterflies are quite common; they are the bluish-grayish butterflies that flutter at your feet as you walk through a grassy meadow. I missed my favorite dragonfly, the twelve spotted skimmer, but had nice looks at both black and red saddlebags near the columns, as well as several other odonates throughout the Arboretum.
As Reya noted, today was a gorgeous day in Washington; it was sunny and not too hot yet. From a birding perspective, the day was even better. Most birds were still singing, and beautiful birds were plentiful in all corners of the Arboretum.
BIRD SPECIES: 45
Canada Goose
Mallard
Red-shouldered Hawk
Mourning Dove
Yellow-billed Cuckoo
Chimney Swift
Ruby-throated Hummingbird
Belted Kingfisher
Red-bellied Woodpecker
Downy Woodpecker
Hairy Woodpecker
Northern Flicker
Eastern Wood-Pewee
Acadian Flycatcher
Eastern Phoebe
Great Crested Flycatcher
Eastern Kingbird
Barn Swallow
Cedar Waxwing
Carolina Wren
Gray Catbird
Northern Mockingbird
Brown Thrasher
Wood Thrush
American Robin
Blue-gray Gnatcatcher
Carolina Chickadee
Tufted Titmouse
Blue Jay
American Crow
Fish Crow
European Starling
Red-eyed Vireo
Northern Parula
Common Yellowthroat
Eastern Towhee
Chipping Sparrow
Song Sparrow
Northern Cardinal
Blue Grosbeak
Indigo Bunting
Red-winged Blackbird
Common Grackle
Brown-headed Cowbird
American Goldfinch
BUTTERFLIES: 8
Eastern Tiger Swallowtail
Cabbage White
Clouded Sulphur
Eastern Tailed-Blue
Variegated Fritillary
Great Spangled Fritillary
Red Admiral
Little Wood-Satyr
ODONATES: 8
Ebony Jewelwing
Spangled Skimmer
Widow Skimmer
Common Whitetail
Blue Dasher
Eastern Amberwing
Black Saddlebags
Red Saddlebags
