4th International PIF Conference Proceedings Published

Proceedings of the 4th International Partners in Flight (PIF) Conference have just been published and are available as a link on the PIF website. Held in McAllen, Texas on 13–16 February 2008, the conference's theme was Tundra to Tropics: Connecting Birds, Habitats and People. VCE staff Chris Rimmer and Kent McFarland were among the nearly 700 people in attendance, >100 of whom hailed from countries other than the U.S.; these included our Hispaniolan colleagues Esteban Garrido and Enold Loius Jean. There were nearly 500 oral and poster presentations among the conference’s 39 individual sessions, including a talk by Chris Rimmer.

The proceedings feature >700 pages of technical papers that focus on identifying priority needs and implementation actions to advance the conservation of birds. Themes range from basic biology, to anthropogenic impacts, to decision support tools, to education and outreach, to inventory and monitoring of avian populations. With colleague Jason Townsend from SUNY ESF, VCE coauthored a paper, "Investigating the Limiting Factors of a Rare, Vulnerable Species: Bicknell's Thrush" in the Basic Biology section.

The PIF proceedings provide a wealth of vital information that will guide conservation planning and policy decision-making for Nearctic-Neotropical migrants, as well as research and monitoring, for years to come.

Tribute to the Bobolink's vocal repertoire

Nature sounds recording artist Elliott Lang captures on video the complex and diverse songs and calls given by breeding Bobolinks. A delightful mid-winter treat.

Petrels, Pines and People on Pic Macaya

VCE colleagues and former staff biologists Jim Goetz and Julie Hart are fresh off an epic trip to Haiti's Pic Macaya and have relayed a few highlights of their adventure (see their first report). They were accompanied by our longtime Haitian partners, Enold Louis Jean and Anderson Jean, as well as a retinue of mules, porters, and guides. Reaching the nearly 2,350 meter summit required an arduous 2-day hike, involving much clearing of downed and overgrown vegetation from the seldom-used trail.

The crew spent 3 nights on Pic Macaya, from December 14-16, their primary quest being to conduct surveys for the critically endangered Black-capped Petrel, which was formerly known to breed on Macaya's cliffs. After hearing the distant calls of petrels each of the first two nights, Jim et al. finally localized the birds by hiking downslope to a saddle between Macaya and adjacent Pic Formon. From here, the group was treated to a spectacle of petrels flying and calling overhead, often at eye level. A bright headlamp revealed at least 6 individuals flying in circles, in groups of 2-6. Jim estimates that there may have been >6 birds, but no more than 10. He suspects that December may be a month of relatively low petrel numbers at breeding sites, as older adults are likely at sea fattening up in advance of laying and incubation.

Jim reports that Macaya's core forest habitat appears to be regenerating strongly from a devastating 2006 fire that burned from the south right up to the summit. Unfortunately, most of the giant pines (some >1.3m [4 feet] in diamater) have died in the wake of the fire. Approximately one in five remain standing, but only half of those survived the fire. On the bright side, the broadleaf undergrowth, which was virtually destroyed in 2006, is now 2 m tall and very thick, and many small pines are sprouting from massive fallen trunks.

A discouraging finding was that a more recent (c. 2008), and slightly less extensive fire burned habitat nearly up to Macaya's summit about 500m west of the saddle. At the burn site on the ridgeline, the group saw 10 goats, and a house in the river valley below. A view of Macaya on Google Earth reveals that its core habitat is only about 800 m from the nearest clearings to the north. It may be telling that local colleagues report it is difficult to find coffee pickers on the west side of the Park because transporting pine boards pays so much better. More than ever, the Macaya Biosphere Resere continues to need swift, effective action to preserve its biodiversity riches as well as the vital ecosystem services it provides.

In addition to their Black-capped Petrel discoveries, Jim, Julie, Enold, and Anderson succeeded in finding a number of Golden Swallows, one flock of Hispaniolan Crossbills, and two Bicknell's Thrushes. The high-elevation forests are still intact and lush where they have escaped the recent fires, but it is clear that threats to Haiti's last bastion of extensive primary forest are mounting. This trip should serve as yet another call to action by the international conservation community, which is increasingly galvanizing resources for the region.

COSEWIC: More Species Closer to Extinction

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) met in Ottawa from November 23-27 to assess the risk of extinction for Canadian wildlife species. The Birds Specialist Subcommittee, which is co-chaired by Dr. Marty Leonard (Dalhousie University) and Jon McCracken (Bird Studies Canada’s Director of National Programs), presented status reports for seven bird species at the November meetings.

Of these, the previously-assessed status was reconfirmed for five: Greater Prairie-Chicken (Extirpated), Eskimo Curlew and Mountain Plover (Endangered), and Yellow Rail and the princeps (“Ipswich”) subspecies of Savannah Sparrow (Special Concern). Given that there have been no verified sightings of the Eskimo Curlew anywhere since 1963, this species is on the brink of becoming the first Canadian bird to be declared Extinct since the Passenger Pigeon nearly 100 years ago.

Two bird species were upgraded to a higher category of risk. The newly-assessed Chestnut-collared Longspur was designated Threatened, based on results from volunteer-based monitoring programs like the Breeding Bird Survey showing that severe population declines this species has suffered since the 1960s are continuing (albeit at a slower rate). This native prairie grassland specialist is threatened by habitat loss and fragmentation from road development associated with the energy sector.

The Bicknell’s Thrush, previously considered a species of Special Concern, was uplisted to a designation of Threatened. Data from the Maritimes Breeding Bird Atlas project and the High Elevation Landbird Program were instrumental to this consideration, documenting declines in the occupied area (in QC, NB, and NS) over the last three generations. While reasons for the decline are unclear, habitat loss on the wintering grounds, management practices such as pre-commercial thinning in regenerating forests, and climate change are leading to a reduction of suitable high-elevation habitat.

More information can be found on the COSEWIC website.

The Second Atlas of the Breeding Birds of Québec

Just over 25 years after the start of fieldwork for the first Québec atlas, Bird Studies Canada, Regroupement QuébecOiseaux, and Environment Canada have joined forces to work on the second Atlas of the Breeding Birds of Québec. While the first atlas was largely limited to the southern part of Québec, this time every effort will be made to cover the whole of the province, making this one of the largest avian research projects ever undertaken in the province.

Fieldwork for the atlas will begin in spring 2010, and will be conducted over a period of at least five years. Once completed, the second atlas will provide up-to-date information about the distribution and abundance of bird species nesting in Québec, and a measure of the changes that have occurred over the past two decades. This powerful tool for the conservation of bird populations in Québec will also identify hotspots of avian biodiversity, and help determine whether populations of species at risk are declining or increasing.

If you’re interested in participating in the atlas, making a donation, or obtaining further information, please visit the Québec breeding bird atlas website, which will be regularly updated.

VCE Colleagues Report from Haiti's Pic Macaya

Welcome second-hand news was received earlier today from VCE friend Paul Rudenberg in Les Cayes, Haiti. Paul reported that he had received a cell phone call from the most unlikely of places -- the summit of Pic Macaya, at nearly 2,350 meters (7000 feet) elevation the Massif de la Hotte's highest and most remote peak. VCE colleagues and former staff Jim Goetz and Julie Hart, together with our colleagues Enold Louis Jean and Anderson Jean of the Audubon Center in Les Cayes, reached the top of Pic Macaya after a grueling 2-day hike. They reported uncharacteristically fine weather and were searching for a campsite under the towering Hispaniolan pines as they called in to Paul.

The team is on a weeklong quest to conduct surveys for the critically endangered Black-capped Petrel, a seabird that comes ashore each November and December to breed on high-elevation cliffs of Haiti and the Dominican Republic. The species' stronghold is in eastern Haiti's Massif de la Selle range, but Macaya is believed to harbor a breeding population as well. Its life history and conservation status are poorly known, but numbers are believed to have declined to alarmingly low levels, perhaps fewer than 1,000 individuals. Goetz, currently a graduate student at Cornell University, and his team hope to document the locations and abundance of breeding petrels in Macaya, as part of a broader effort to conserve the species and its threatened habitats.

VCE's field expeditions to the Macaya Biosphere Reserve in 2004 and 2006 helped to establish the area's importance as one of Haiti's last remaining large tracts of intact forest. The region's remnant pine forests, featuring some of Hispaniola's most massive trees, and its karst broadleaf forests support an impressive array of flora and fauna, much of it endemic. It is one of only two areas in Haiti known to be inhabited by wintering Bicknell's Thrush, and it is a crucial refuge for other migrant and resident birds. Fortunately, the conservation tide may be turning, as the international community is beginning to devote attention and resources to this beleaguered area, accompanied by a groundswell of local commitment by dedicated individuals like Enold and Anderson, and staff of the Societe Audubon Haiti. There is reason for optimism.

Stay tuned for a field update from Jim, Julie and their team!

Mercury in the Mountains

VCE Biologists Track a Toxin’s Movement through the Food Web

Offering novel insights into mercury’s threat to wildlife, the Vermont Center for Ecostudies (VCE) has for the first time revealed how this insidious toxin moves and concentrates across the food chain in forest ecosystems. In newly published research, VCE biologists tracked mercury up the food web – from tree needles and leaves to insects and spiders to salamanders and songbirds, and in due course to top predators such as hawks and owls. VCE’s work, published in the journal Ecotoxicology, is significant because it documents patterns of mercury’s migration through a forest ecosystem. The research could help inform the development of strategies to ease mercury’s dangerous effects on ecosystems and their wildlife inhabitants.

Read more on our Research Notes page...

Full Published Article:
Rimmer, C.C., E.K. Miller, K.P. McFarland, R.J. Taylor, and S.D. Faccio. 2009. Mercury bioaccumulation and trophic transfer in the terrestrial food web of a montane forest. Ecotoxicology. DOI 10.1007s10646-009-0443-x.

Norwich BirdQuest 2010

Long-tailed Duck. Green Heron. Blue-gray Gnatcatcher. Lesser Yellowlegs. Blackburnian Warbler. From the common to the rare, a fascinating array of birds resides in or passes through Norwich each year. Yet, just how many species actually nest in our town, or touch down during their migrations? Are there little-known ‘birding hotspots’ in Norwich? Are there unknown sites within our town’s borders that have important conservation value for birds?

If you enjoy watching birds, wish to know more about Norwich’s avian diversity, or simply want to get out and explore our town’s varied habitats, you’re ripe to participate in the Norwich 2010 Birding Quest.

A group of four committed Norwich birders, under the aegis of the Vermont Center for Ecostudies (VCE), is embarking on a yearlong pursuit that promises to be fun, educational, and full of surprises. The basic goal is to find and identify as many species of birds as possible within Norwich town lines during calendar year 2010. We’ve set our sights on a cumulative total of 150 – an ambitious but achievable target. Our primary incentive is recreational, having fun outside watching birds as often as possible. Hand in hand with that self-serving motive is our ambition to better document Norwich’s diversity of birdlife. With many bird populations in decline across North America, there is an increasing need to understand patterns and trends as a first step towards conservation. Birds are excellent ecological indicators (recall the iconic canary in the coal mine), and their patterns of abundance and distribution (where and when they occur) can tell us a great deal about ecosystem health, even at a local, townwide scale.

In addition to the insights they provide on biology and conservation, birds offer a rich window for participation in our natural world. Thus, we have other goals for the Norwich 2010 Birding Quest. Specifically, we hope to:

o Engage Norwich residents and others to get out birding, thereby increasing local awareness of birds and their conservation
o Encourage Norwich residents to explore and become better acquainted with our town
o Stimulate Norwich’s youth to become interested in birding
o Identify birding ‘hot spots’ in Norwich – places where diversity or numbers of birds are relatively high, and/or that offer good opportunities to observe birds
o Encourage use of Vermont eBird, an easy-to-use, on-line checklist program that provides an invaluable data resource on bird populations across the hemisphere

Here’s how the Norwich 2010 Birding Quest will work. Beginning on January 1, when the annual Hanover-Norwich Christmas Bird Count is held, we will begin compiling a master list of species tallied within the Norwich town lines. Spencer and Doug Hardy will be keepers of this list and overall coordinators of the yearlong effort.

We'd like you to contribute all of your bird sightings, from the common to the rare, to Vermont eBird and share your checklists with the Norwich Bird Questers. Sharing is easy. If you already don't have one, sign up for a Vermont eBird account. Every time you you enter a checklist from someplace in Norwich, simply share it with us. Our username is "Norwich". After you submit a checklist you will be asked if you wish to share it. Just make us an eBird friend and share all of your Norwich bird sightings with us. There's a tutorial for eBird and for sharing your checklists with eBird friends.

We will have a Norwich Bird Quest 2010 page on the VCE web site and we’ll post regular updates and special features on the VCE blog . We will offer informal workshops on using eBird, and we’ll organize periodic field trips to local birding spots throughout the year. Dates and locations for all these events will be announced on the web page.

We welcome any and all residents of Norwich and other towns to participate, whether watching birds at your feeder, scanning the Connecticut River from Ledyard Bridge, or keeping notes as you hike in your favorite patch of Norwich woodland. Challenge yourself and your birding cohorts to a friendly competition for the highest 2010 species total! The only “rule” is that you (the birder) must be within Norwich town lines – the birds can be overhead, on the river, even in another town.

Join this fun, informal quest, and contribute to a better understanding of Norwich’s bird life! Amateur birders have made enormous contributions to avian research and population monitoring in North America over the past century. Become one of those “citizen scientists” yourself by participating in this effort. You’ll have fun exploring Norwich’s special places, you’ll meet new people, you’ll contribute to conservation, and you’ll undoubtedly make some unexpected and exciting discoveries.

Chris Rimmer, Spencer Hardy, Doug Hardy, and George Clark

Study reveals how Arctic food webs affect mercury in polar bears

With growing concerns about the effects of global warming on polar bears, it's increasingly important to understand how other environmental threats, such as mercury pollution, are affecting these magnificent Arctic animals.

New research led by biogeochemists Travis Horton of the University of Canterbury and Joel Blum of the University of Michigan lays the groundwork for assessing current and future effects of mercury deposition and climate change on polar bears.

The study appears in the December issue of the journal Polar Research.

Mercury is a naturally occurring element, but some 150 tons of it enter the environment each year from human-generated sources such as coal-burning power plants, incinerators and chlorine-producing plants. Deposited onto land or into water, mercury is picked up by microorganisms, which convert some of it to methylmercury, a highly toxic form that builds up in fish and the animals that eat them. As bigger animals eat smaller ones, the methylmercury is concentrated---a process known as bioaccumulation. Sitting at the top of the food chain, polar bears amass high concentrations of the contaminant.

Although that much is known, the details of how mercury moves through different food webs---particularly in the Arctic, where snow and ice contribute to mercury deposition---are not well understood. To tease out that information, Horton, Blum and co-workers studied polar bear hair samples from museum specimens collected in the late 19th and early 20th centuries, before mercury emissions from human-generated sources began to escalate.

By looking at three chemical signatures---nitrogen isotopes, carbon isotopes and mercury concentrations---the researchers learned that polar bears get their nutrition (and mercury) from two main food webs. At the base of one web are microscopic plants that float on the surface of the ocean (known as phytoplankton). The foundation of the second web is algae that live on sea ice.

The study showed that polar bears that get most of their nutrition from phytoplankton-based food webs have greater mercury concentrations than those that participate primarily in ice algae-based webs.

While it's tempting to speculate that declining sea ice, due to global warming, may force polar bears to depend more on phytoplankton-based webs, thus increasing their mercury exposure, the study doesn't directly address that issue. It does, however, provide other useful information, said Blum, who is the John D. MacArthur Professor of Geological Sciences and a professor of ecology and evolutionary biology.

"If you want to understand the potential effects of changing ecosystems on polar bears, you need to be aware of the existence of these two food webs, which may possibly be affected by sea ice," Blum said. "This work provides background information that will be important in our in-depth understanding of mercury bioaccumulation in polar bears."

More information:
Joel Blum: www.ns.umich.edu/htdocs/public/experts/ExpDisplay.php?beginswith=Blum
Polar research: www.wiley.com/bw/journal.asp?ref=0800-0395

Recent unprecedented tree-ring growth in bristlecone pine at the highest elevations and possible causes

Great Basin bristlecone pine (Pinus longaeva) at 3 sites in western North America near the upper elevation limit of tree growth showed ring growth in the second half of the 20th century that was greater than during any other 50-year period in the last 3,700 years. The accelerated growth is suggestive of an environmental change unprecedented in millennia. The high growth is not overestimated because of standardization techniques, and it is unlikely that it is a result of a change in tree growth form or that it is predominantly caused by CO₂ fertilization. The growth surge has occurred only in a limited elevational band within ≈150 m of upper treeline, regardless of treeline elevation. Both an independent proxy record of temperature and high-elevation meteorological temperature data are positively and significantly correlated with upper-treeline ring width both before and during the high-growth interval. Increasing temperature at high elevations is likely a prominent factor in the modern unprecedented level of growth for Pinus longaeva at these sites.

Matthew W. Salzer, Malcolm K. Hughes, Andrew G. Bunn, and Kurt F. Kipfmueller. 2009. Recent unprecedented tree-ring growth in bristlecone pine at the highest elevations and possible causes. PNAS 2009 106:20348-20353. doi:10.1073/pnas.0903029106

Foresters Learn to Help Bicknell’s Thrush

Bird Study Canada's Atlantic Canada Program Manager and International Bicknell's Thrush Working Group (IBTCG) co-chair, Becky Whittam, recently gave a presentation in Port Hawkesbury, Nova Scotia for 16 members of the Nova Scotia Forest Products Association. The talk, “Forest Management Options for the Bicknell’s Thrush: Reducing Incidental Take of a Bird Species at Risk,” included information about habitat requirements of the Bicknell’s Thrush, an elusive songbird that nests in the high elevation coniferous forests of Nova Scotia’s Cape Breton Highlands. The Bicknell’s Thrush, federally listed as a Threatened species in Canada, uses regenerating industrial forest about five to fifteen years post-harvest, coinciding with the period during which pre-commercial thinning is often scheduled.
Whittam presented the current habitat model that was completed by the Vermont Center for Ecostudies for this species in NS and across the entire breeding range, including specifics on the age and composition of industrial stands coinciding with the habitat model. Her presentation covered best management practices to reduce incidental take of this species, and long-term forest management options to maintain its habitat. She also provided training on how to identify this species while working in the forest.

List of 'unsung' wildlife affected by climate change released

The Wildlife Conservation Society today released a list of animals facing new impacts by climate change, some in strange and unexpected ways.

In a new report titled "Species Feeling the Heat: Connecting Deforestation and Climate Change," the Wildlife Conservation Society profiles more than a dozen animal species and groups that are facing threats due to climate change impacts including: changing land and sea temperatures; shifting rain patterns; exposure to new pathogens and disease; and increased threats of predation.

The Wildlife Conservation Society is issuing this report as the world gathers in Copenhagen to address climate change issues and as the United Nations launches in 2010 the International Year of Biodiversity, a UN-led effort to raise awareness to reduce the constant loss of biological diversity worldwide. The Convention on Biodiversity, which emerged from the 1992 Rio Earth Summit, recently admitted that none of its 2010 biodiversity targets have been met, underscoring the dire situation wildlife around the world face from burgeoning threats such as climate change.

The report also highlights the huge role of deforestation in climate change. Nearly 20 percent of greenhouse gas emissions are the result of deforestation, more than the output of all the world's trucks, trains, cars, planes, and ships combined, so protecting the remaining swaths of the world's forests can help put the breaks on climate change.

"The image of a forlorn looking polar bear on a tiny ice floe has become the public's image of climate change in nature, but the impact reaches species in nearly every habitat in the world's wild places," said Dr. Steven E. Sanderson, President and CEO of the Wildlife Conservation Society. "In fact, our own researchers are observing direct impacts on a wide range of species across the world."

The report contains a cross-section of animal species around the globe, including:

• Bicknell's thrush, a bird species that breeds and nests in the higher elevations on mountains in northeastern North America. Slight increases in temperature threaten this bird's breeding habitat.
• Flamingos, a group including several species that are threatened by climate change impacts that affect the availability and quality of wetland habitat in the Caribbean, South America, Asia, and Africa.
• Irrawaddy dolphin, a coastal species that relies on the flow of fresh water from estuaries in Bangladesh and elsewhere in Southeast Asia. Changes in freshwater flow and salinity may have an impact on the species long-term survival.
• Musk ox, a species that exists in the harsh environment of the Arctic Tundra. This Pleistocene faces a higher predation risk by grizzly bears, as more bears may move northward into the musk oxen's tundra home.
• Hawksbill turtle, an ocean-going reptile with temperature dependent biology. Specifically, higher temperatures result in more female hatchlings, a factor that could impact the species' long-term survival by skewing sex ratios.

"Aside from all of the current political disagreements on meteorological data, we can say with certainty that climate change is threatening our planet with significant losses to wildlife and wild places," added Sanderson.

Rejection of Cement Plant in DR's Los Haitises Will Benefit Critically Endangered Ridgway's Hawk

Santo Domingo, November 27, 2009

The United Nations multi-sectorial team charged with evaluating the decision to install a cement plant in a buffer zone of the Dominican Republic's Los Haitises National Park has concluded that the project is neither viable nor pertinent. Los Haitises is known as one of the world's largest karst reserves, and is an important source of reserve water for the country. In addition, the region is the last stronghold of Ridgway's Hawk, reputed to be the world's rarest and most endangered raptor, with only about 100 breeding pairs remaining. Further, the area has significant cultural heritage, as reflected in Taino cave drawings.

United Nations Development Program (UNDP) representative in the DR, Valerie Julliand, described the Los Haitises case as "a historic moment of growth for the national society." She stressed that it showed how civil society, the private sector and the general public could work together to resolve an environmental conflict. "A country will develop when all its actors come together and contribute," she said. "This is a historic moment for the country, for society and for the strengthening of Dominican institutions."

The announcement, which was made at the UN Office in Santo Domingo on November 26, was received with hugs, loud applause and cheers, with the feeling being that it represented a victory for civic action. The Presidency called in the UN to deliver an opinion after widespread public rejection of the proposal, as reflected in a Gallup Poll showing that 85% of Dominicans were opposed to construction on the site. Ministry of Environment specialists originally rejected the project, but President Leonel Fernandez overruled their decision.

Speaking on behalf of the UNDP commission, environmental impact consultant Eduardo Vadillo Sanchez said that their analysis concluded that there was not sufficient information from the environmental impact study to allow construction of the cement plant to proceed. During the press conference, Julliand said that the announcement clarified that the project would not be viable in any other areas near the karst region of Los Haitises. The group concluded that the benefits and opportunities for the area did not justify the risks and high costs to society, and decided on these grounds that the project is not pertinent. Vadillo said their conclusions were backed by scientific facts. Domingo Abreu, an environmentalist who championed the group of young people who led the campaigns against the project, said that the decision is an endorsement of Dominican environmental specialists who early on had reached the same conclusion. He urged the government to listen to Dominican experts in the future.

The decision is a welcome one for bird conservationists. Ongoing studies of the ecology and breeding status of Ridgway's Hawk, whose tenuous populations were at risk from the proposed plant, are being conducted by the Sociedad Ornitologica de la Hispaniola and the Peregrine Fund. Conservation efforts by these two groups include releases of wild-hatched nestlings into two other areas of the country, in hopes that self-sustaining populations will become established.

Focus on Science: Stone-swallowing by Cormorants to Thwart Internal Parasites

Many species of birds are known to consume inorganic materials as part of their diet. Small stones and grit aid in grinding up coarse food items such as seeds and nuts, while clay may provide nutritional supplements or neutralize toxic secondary plant compounds. However, ornithologists have puzzled over why small stones are also taken, though less frequently, by birds that eat meat, fish, or fruit. Such birds, particularly those higher on the food chain, may host nematode worms in their stomach. This knowledge led Robinson and his colleagues to suspect that these birds might consume small stones in order to rid themselves of the worms attached to their stomach wall.

The researchers investigated Double-crested Cormorants (Phalacrocorax auritus), a predominantly fish-eating species that is commonly parasitized by various nematodes ingested through their diet. Sampling birds on Lake Ontario and Lake Erie, they discovered small stones in the stomachs of 13-17% of the cormorants. On Lake Ontario, females more often had small stones and were less infected by certain species of nematodes than were males. The abundance of these parasites was statistically the same whether the stomachs of female cormorants contained or lacked stones. Males with stones, however, had fewer nematodes than those without stones. Lake Erie birds had fewer parasites than Lake Ontario birds, and relatively fewer of them had ingested small stones. Male and female Lake Erie cormorants did not differ in the occurrence of stones, and the presence or absence of stones was unrelated to the abundance of nematodes.

These results suggest that consuming small stones may protect Double-crested Cormorants against high levels of infestation by certain nematodes. The lower incidence of parasites and ingestion of stones by Lake Erie birds further suggests that cormorants do not routinely use this behavior as an anti-parasite “therapy”. They may do so only in situations where nematodes are abundant and birds are able to somehow sense the parasites’ detrimental impacts on their fitness or energy.

Robinson and his colleagues considered three alternate possibilities for the presence of small stones in cormorant stomachs: (1) they help mix food items, (2) they help adjust buoyancy when diving, or (3) they are consumed accidentally. The researchers ruled out each of these explanations, although they could not exclude the possibility that fish taken as prey by the cormorants might swallow and harbor the stones themselves.

The cormorants’ apparent habit of ridding themselves of stomach parasites is consistent with other known cases of self-treatment by animals. Sea lions, for example, swallow stones, evidently to eradicate parasites from the stomach, and chimpanzees swallow hairy leaves for a similar purpose. European Starlings (Sturnus vulgaris) are known to add specific kinds of vegetation to their nests to repel ectoparasites. Instances of similar therapeutic behavior to combat external or internal parasites may be more widespread among birds than we humans have realized.

Peter Stettenheim -– Peter is a retired ornithologist with particular interests in the functional anatomy and evolution of birds. He lives in Plainfield, NH.

ROBINSON, STACEY A., MARK R. FORBES, AND CRAIG E. HEBERT. 2008. Is the ingestion of small stones by Double-crested Cormorants a self-medication behavior? Condor 110: 782-785.

Birds call to warn friends and enemies

Birds' alarm calls serve both to alert other birds to danger and to warn off predators. And some birds can pull a ventriloquist's trick, singing from the side of their mouths, according to a UC Davis study.

Many animals respond vocally when they detect predators, but it's not clear to whom they are signaling, said Jessica Yorzinski, a graduate student in animal behavior at UC Davis who conducted the study with Gail Patricelli, professor of evolution and ecology. They might be warning others of the threat, but they might also be telling the predator, "I've seen you."

Yorzinski used a ring of directional microphones around a birdcage to record the songs of dark-eyed juncos, yellow-rumped warblers, house finches and other birds as they were shown a stuffed owl. All the birds were captured in the wild, tested, banded and released within 24 hours.

Overall, the birds' alarm calls were relatively omnidirectional, suggesting that they were given to warn other birds in the vicinity. However, the main species tested -- juncos, warblers and finches -- all showed an ability to focus their calls in the direction of the owl, so these calls could also function to warn off a predator.

House finches were the least directional in their calls. They are also the most social of the species tested, Yorzinski noted.

Some of the birds were able to project a call in one direction while their beak was pointed in another.

"It's like talking out of the corner of their mouths," Yorzinski said. In some cases the birds may see better sideways than forwards, although Yorzinski did record evidence of birds projecting calls both forward and to either side.

"It's not clear how they're accomplishing this," Yorzinski said.

Photograph Caption: This is the microphone recording array used for the experiments. Credit: Marc Dantzker

Biologists discover rare butterfly in Maine - Bangor Daily News

I guess this should read, a rare butterfly for Maine....

A species of butterfly has been rediscovered in Maine 75 years after it was last reported seen in the state. The Inland Fisheries and Wildlife Department set out last summer to confirm whether the spicebush swallowtail lived in Maine. Maine is at the northern end of the butterfly’s range, and the only documented Maine sighting was in 1934, said wildlife biologist Phillip deMaynadier.