Sunday, August 27, 2006
Researchers work to ensure survival of a rare songbird
Newsday - Long Island,NY,USA
... The fledgling was a rare Bicknell's Thrush, subject of a long-term study by the Vermont Institute of Natural Science on the bird's breeding grounds at high ...
Julie Hart and I are deploying night migration recording devices over the next week or so at 3 sites: East Woodstock, VINS Quechee Center, N. Hartland. We hope to keep up as much as possible with results and post them here.
Last night I deployed a microphone in Woodstock. I used a shotgun microphone, but we are in the process of building microphones as explained here by Bill Evans of Old Bird, Inc.
I recorded from 830pm until 530am last night/this morning. I then used software from Old Bird to filter out Thrush like calls and tseep calls (warblers and sparrows).
I just about lost my mind with the thrush like calls as a lot of cricket calls were picked up so it took me over an hour to go through 1,200 calls to find the only two thrush calls all night - 2 Veery calls. tseep calls produced 15 birds. Tentatively identified as:
Ovenbird - 9
Chestnut-sided Warbler - 3
Common Yellowthroat - 2
zeep complex (Blackburnian Warbler?) - 1
Stay tuned this fall for more night migration reports.
Friday, August 25, 2006
A member of the Nightjar family, the nighthawk is closely related to the Whippoorwill, with which it shares perhaps the best cryptic coloration of any of our breeding bird species. Just try and find a nighthawk perched on a branch or incubating its eggs on the ground. Several behavioral adaptations enhance this superb camouflage, including squeezing their large eyes closed during the day, and perching along the axis of a limb, rather than perpendicular to it, so they resemble a branch stub.
Although nighthawks may be inconspicuous while perched, their booming courtship display is anything but. During the breeding period, the male circles above the nest site at twilight uttering sharp, nasal, peent calls. Then, once every minute or so, he dives down sharply toward the nest, making an abrupt turn upward within a few feet of the ground while flexing his wings downward. As air rushes through his wings, vibrating his primary feathers, it produces a distinct vrooom sound that can be heard up to several hundred feet away.
At the turn of the last century, nighthawks were likely much more common in Vermont than they are today. As farms and open pastureland reverted back to forest and urban areas increased, Common Nighthawks switched to nesting on flat-topped gravel roofs. During the last 25 years however, populations continued to decline, even in cities where they were once abundant. This may be due to widespread use of pesticides for mosquito control, and to a change from gravel roofing to a smooth, rubberized material in urban areas.
Common Nighthawks are one of the last birds to arrive on northern breeding grounds in spring, and are among the first to depart for their South American wintering grounds. In Vermont, southbound migration peaks during late-August and early-September. Keep an eye out for small flocks of 10-20 nighthawks during the next few weeks. They are frequently seen swooping and circling above river valleys and farm fields as they forage, often silently, on their way south, their conspicuous white wing patches flashing with each wingbeat. Occasionally huge flocks of up to 400 birds may be seen, particularly in the Connecticut River valley, which apparently serves as an important nighthawk flyway through New England.
You can learn about all bird sightings the past week and more on Vermont eBird.
VINS Conservation Biologist
On a birding trip yesterday to the coast, we paid a visit to the famous Western Reef-Heron. This digiscope photo isn't great, but was the best we could do in poor lighting conditions. Stokes have some great photos of the bird on thier blog.
We traveled to Portsmouth, NH looking for the bird by looking for the birders. But, to our surprise there was not a single birder around. But at 4:30pm, Bryan Pfeiffer spotted the bird out the car window on a small island. We quickly piled out of the car and watched the bird from the Riverside Cemetery in New Castle. See map in Topozone for precise location.
Normally occurring from western Africa east into India, this bird is quite far from home! Earlier this summer, a Western Reef-Heron, North America’s 3rd record (Martha’s Vineyard, April 26 – September 13th, 1983 and Newfoundland last summer were the previous two records) was discovered in Nova Scotia. About 2 weeks ago it disappeared and may be this bird.
Kent McFarland, VINS Ornithologist
An Adirondack Ski Resort Takes Steps to Accommodate an Elusive Little Bird
... Bicknell's thrushes, and it may get kicked around,” said Chris Rimmer, the director of conservation biology at the Vermont Institute of Natural Science, a nonprofit ...
Read the entire story: An Adirondack Ski Resort Takes Steps to Accommodate an Elusive ...
Friday, August 18, 2006
Wrens are extremely loud, energetic birds for their small size. They are most easily recognized by their upturned tail and harsh, chattering alarm calls. The most familiar member of the wren family is the House Wren, which commonly nests in birdhouses.
One of the many peculiar habits of House Wrens is the manner in which they build their nests. When the males arrive on territory in late April-early May, they often start to build multiple nests, hoping that prospective females will be attracted to one of them. In addition, they are extremely territorial, so they are known to build in occupied nests as well, destroying the eggs of the former tenant. In some areas, this behavior can be the primary cause of nest failure for birds like chickadees, Tree Swallows, and bluebirds.
Despite the seemingly malicious behavior of nest usurpation, wrens can also be amusing in the unusual variety of places in which they build their nests. In addition to birdhouses and natural cavities in trees, they have been known to nest in aluminum cans, watering cans, pockets in clothing, paper nests of hornets or wasps, farm machinery, old boots and shoes, and have even been documented nesting in a recess in an Osprey nest.
House Wrens have also been observed feeding the young of other species. This behavior has occurred in unmated birds and birds anticipating the hatching of their own chicks. On a few occasions, wrens have been seen feeding flickers, Black-headed Grosbeaks, and House Sparrows.
Nesting is no laughing matter for house wrens, though, and most will successfully raise two broods before they leave for the southern states in early September. Right now, you can still find wrens throughout Vermont busily attending to their nests and young.
Most of the breeding birds in our area have raised young and are now preparing to migrate. Among the few species still being reported as showing signs of breeding activity include Vesper Sparrow in Island Pond on the 11th and American Black Duck in Alburg on the 14th.
A Carolina Wren has been vocalizing in East Dorset this past week while juvenile Eastern Towhee, House Finch, Rose-breasted Grosbeak, Chipping Sparrow, and Northern Cardinal visited feeders nearby on 12 August. A juvenile Bicknell's Thrush was seen and heard on Haystack Mountain in Wilmington on the 9th.
A Peregrine Falcon and Brewster's Warbler were observed in Brandon on the 15th.
You can learn about all bird sightings the past week and more on Vermont eBird.
-Julie Hart, VINS Ornithologist
Sunday, August 13, 2006
Rare songbird protected through historic partnership included in Whiteface Mountain Unit Management Plan.
RAY BROOK, NY – Rare songbird protected through historic partnership included in Whiteface Mountain Unit Management Plan.
In 2003, during planning for additional ski trails (Tree Island Pod) in the high elevation zone of Whiteface Mountain Ski Area, the Bicknell’s thrush, a species of special concern in New York State, was introduced to many people in the North Country for the first time. This bird is a neo-tropical migrant, spending the winter almost exclusively in mountain forests in the Dominican Republic and spending the summer breeding season here in the mountain regions of northeastern United States. The Adirondacks and White Mountains of New Hampshire contain the majority of the breeding habitat for this species.
Bicknell’s thrushes live in the thick spruce-fir forests above 2,800 feet on Adirondack mountainsides. This bird especially prefers “fir waves,” which can be seen on Whiteface and Esther Mountains. Fir waves are a natural phenomenon of patterned forest disturbance, and they work such that the tallest trees are the first in line to be exposed to prevailing winds and rime ice. The tall trees die and shorter trees grow up in their place, but these trees eventually get exposed to the elements and die. This cyclic pattern continues and appears as a moving “wave” of dead and regenerating trees across the mountainside. Fir waves make hiking very challenging, as anyone who has ever climbed Esther Mountain can attest, but this messiness is just what a Bicknell’s thrush likes.
As part of the unit management planning efforts for the Whiteface Mountain Ski Area a working group was formed that included representatives from the Adirondack Park Agency, Olympic Regional Development Authority, Department of Environmental Conservation, Vermont Institute of Natural Sciences, Wildlife Conservation Society, The Adirondack Council, Audubon New York, Cornell Lab of Ornithology, and the Adirondack Nature Conservancy. This extraordinary partnership has resulted in an ongoing study of Bicknell’s thrush and its habitat on Whiteface Mountain. Recommendations from the working group were incorporated by ORDA into the final unit management plan for the ski area and included the relocation of trail development away from areas on the mountain deemed sensitive.
Ted Blazer, Chief Executive Officer for the Olympic Regional Development Authority stated, “ORDA is a willing partner and proud to be included in this joint stewardship effort. It is our goal to educate our residents and guests that as we enjoy the mountain environment and the modern amenities within, there is a sensitivity that we are all mandated to exhibit toward the wildlife, including Bicknell's Thrush at Whiteface. I am happy that we will enhance this process not only with words, but also with deeds.”
The members of the partnership will sign a Cooperative Agreement at 11:00AM on Friday, August 11, 2006 during the regular monthly meeting of the Adirondack Park Agency Board in Ray Brook. A very important component of this agreement is the establishment of a Bicknell’s Thrush Mitigation Fund – a unique international effort, which recognizes that conservation and scientific initiatives are important both in the bird’s North American habitat as well as in its Caribbean wintering grounds.
Adirondack Park Agency Chairman Ross Whaley said, “This is an excellent example of working cooperatively with the best interests of the Adirondacks at heart. Whiteface Mountain is a world-class ski destination that happens to be located on Forest Preserve. ORDA has kept that in the forefront during this planning process. We have a unit management plan before us that reflects the underlying theme of the state land master plan “to protect the natural resources of the Park” and will result in improvements that enhance Whiteface Mountain’s appeal to local skiers and tourists alike.”
“This agreement demonstrates a far-reaching commitment to conserve habitat for this species of special concern,” said New York State Department of Environmental Conservation Commissioner Denise M. Sheehan. “DEC and our partners are safeguarding the Bicknell’s thrush nesting habitat on Whiteface Mountain and with other initiatives like the Bird Conservation Area program, open space preservation successes and ongoing habitat improvements in the Adirondacks and throughout the State and we look forward to building upon these conservation efforts."
David J. Miller, Executive Director of Audubon New York stated, "ORDA is to be commended for its commitment to the cooperative process leading to this progressive management plan that protects Bicknell's Thrush here and on its wintering grounds. The establishment of an international habitat conservation fund to protect winter habitat on Hispaniola addresses the most critical threats facing this important bird species, while still making a serious and significant attempt to accommodate Bicknell's Thrush and its habitat on Whiteface Mountain."
Michale Glennon, ecologist with the Wildlife Conservation Society’s Adirondack Communities and Conservation Program said, "As a science-based organization, we have been pleased to help ensure that good research and good science have been informing the Whiteface planning process on Bicknell's Thrush breeding grounds. We are pleased that this initiative expands our reach as a coalition of organizations and agencies to the thrush's wintering grounds, which are critical for the protection of the species."
There is nothing like a picturesque
The cattle egret is originally from Africa and Asia and only reached the
Cattle egrets tend to follow large animals or farm machinery to catch flushed insects. It has been calculated that an individual cattle egret can obtain up to 50% more food and use only two-thirds as much energy by associating with grazing animals. In
Cattle egrets can fly great distances in a short time. From July to November juveniles rapidly disperse up to 3,000 miles.
The first record of a cattle egret in
Last week there were eleven cattle egrets with the Shelburne Farms cows.
Reports of great egrets, another egret that ranges across much of the world, came from around the state last week. Ten were seen in a Colchester marsh on July 31st, one was near the mouth of the
The highlights of
Friday, August 04, 2006
The Restless on Young
The black-crowned night heron’s namesake is in the eyes of the beheld. A stocky, sleek-dressed heron, it has a black back, gray wings, and a black head featuring a luxurious, long white plume. Its brilliant red eyes are tailored to make this species a night hunter. A layer of tissue called the tapetum lucidum reflects extra light back to the retina. When light fades, night herons put this adaptation to work.
The black-crowned night heron occupies its nocturnal hunting niche in a waterbird drama that is played out each summer on Lake Champlain’s islands. Each spring egrets, herons, terns, ibises and cormorants are driven by hormones to fight aggressively for a 2-foot diameter piece of ground or a branch of a shrub to call their own.
The latest episode features the night herons returning to nest on Young Island after almost a decade of absence. The recent discovery of ready-to-fledge nestlings represents a potential turn of events for the herons on the island after being forced out years ago by double-crested cormorants.
According to University of Vermont researchers, the number of cormorant nests on Lake Champlain has grown from 1 in 1982 to 4,230 in 2005. Their nesting activities denude shrubs and trees, forcing out other waterbirds. Most (83%) of cormorant nests are on Four Brothers Islands, where they produce a deafening chaotic cacophony during the summer months.
Although night herons retain a foothold on Four Brothers, they disappeared from Young Island after nesting there for years. Now that a few box elders have popped up and provided nest substrate, the herons have re-occupied, at least for the moment.
Whether cormorants are the “bad guys” depends on your perspective; night herons have their dark side, literally. Their keen night vision is a bane to some species. For years night herons made meals out of state endangered common tern chicks. Former VINS biologist Mark Labarr took care of the problem by erecting shelters for the chicks.
Like a soap opera, Lake Champlain nesting waterbirds are caught up in a dynamic system where the success of one species can cost another. Each individual’s drive to pass on their genes will ensure that the battle ensues among the restless birds on Young Island.
During the past week, Bonaparte’s gulls seen near the Charlotte ferry dock officially ushered in Lake Champlain’s waterbird migration, which will include thousands more in the coming months. Great egrets and a Caspian tern carrying food at were seen at Four Brothers.
A least bittern was a treat for birders at West Rutland Marsh, and an immature red crossbill was reported at a feeder in Norwich. Breeding observations of relatively late-nesting songbirds have been reported this week, including cedar waxwing and eastern wood-peewee nests, and new yellow-billed cuckoo fledglings.
You can learn about all bird sightings the past week and more on Vermont eBird.
Roz Renfrew, VINS Ornithologist