Loon Update July 2009

Vermont Loonwatch Day 2009
The results of the statewide loonwatch survey on 18 July are coming in via mail, email, and for the first time on VT ebird. It will take a little more time before the actual count data is assembled and final. In 2008, 225 adult loons were counted compared to 106 adult loons in 1998 and 41 in 1988. I personally surveyed 9 lakes a week ago Saturday that were either not assigned or volunteers could not participate at the last minute. I started with a 6:30 am paddle on Great Averill Lake up on the Canadian border. I confirmed a successful nest by finding 2 chicks at the north end with one parent. Further down the lake I found another adult head bobbing (quickly extending its head up high then peering underwater). This behavior is indicative of another loon being nearby, and so there was another ½ mile down the lake. I found one more adult on the return paddle that I could be certain was not one of the 3 adults observed earlier. I moved on to Forest Lake where there had been loon fights on and off for 2 weeks in early July resulting in the loss of one chick. I find 1 adult and 1 chick. Unfortunately, 3 days later I had to return and pick up the carcass of a loon, likely from the fights. We’re still not sure whether this dead loon was one of the parent loons or the intruder as of this writing. Last week, I also picked up a dead loon wrapped in fishing line on Lake Champlain on South Hero Island, and another one on Maidstone Lake. We don’t know the cause of the Maidstone mortality, but hopefully the vets at Tufts University will gather some clues. I also spend a ½ a day searching for a loon supposedly caught up in fishing line on Wallace Pond. I found 4 healthy adults instead. It was a busy week.

Back to Loonwatch day. I head south and swing by Center Pond in Newark and find 2 adults. This pond is large enough for a territorial pair, but we have usually observed 1 or no loons in recent years on the pond. We will survey the pond more often in 2010 with the 2 loon sighting. There are 2 adults loons on Shadow Lake in Concord indicating that the nest failed for the 3rd year in a row. I check out the western end of Moore Reservoir with a spotting scope and binoculars and do not find any loons. I could easily have missed one, but this is both a difficult body of water to survey and even more difficult to find a volunteer willing to take it on. Last year I spent 5 hours paddling the eastern 2/3’s and another couple surveyed the western 1/3; we found 4 adults and 5 bald eagles that day.

I drive over south of St. Johnsbury to hit a bunch of small lakes: Warden Pond (2 adults), Symes Pond (2 adults, 1 chick), and Ticklenaked (1 adult). The volunteer on Symes had forgotten about loonwatch day – it happens to all of us. This was the first survey of the pond this year, thus very rewarding to have a 4 week old chick there. On the way home, I take a quick look at Hardwick Lake and surprisingly find no loons. The pair likely lost their chick in late June right after the hatch based on the egg shell fragments I found on the nesting raft. No chick was actually observed. My totals for the day were 14 adult loons and 4 chicks.
2009 nesting season update:

The loons will set another record for pairs nesting at 65. I need to get out and check a new chick sighting this week. The previous record was 62 in 2007. We’ve had 15 failed nests, but only a few of these were a result of flooding and all the rains this season. 72 of 77 chicks are still with us from the 48 nests that were successful. Two pairs are still incubating. Five new nesting pairs have been identified. We’ve had some interesting territorial location shifts. The volunteers on Lake Dunmore were pretty sure the pair had nested in their usual hidden nest site on the island after only seeing 1 adult in late May. However, in mid-June, it became apparent the single loon was not near the island like it was in past years. Something was different. Sally Buteau, the former VLRP biologist, investigated the island closely and found no sign of nesting. Did we lose the pair? Mike Korkruc, a VLRP volunteer, noticed a loon flying off the lake often. With a little investigation, he realized the loon was flying to a nearby tiny pond and in early July discovered 2 very healthy loon chicks there. It is likely the Dunmore pair has shifted their nest site to a much quieter location and still utilize Lake Dunmore for feeding and resting. We might have a similar situation in Glover with a pair nesting on a large beaver pond, and possibly moving the chicks to nearby Daniels Pond. The chicks disappeared from beaver pond on June 30 and chicks appeared on Daniels July 1. Little loon activity was observed on Daniels Pond in June. I thoroughly checked the Daniels Pond shoreline for a hidden nest and found none. Could 1 week old chicks make a 1/3 mile trek through marsh and shrubby forest? We'll be watching more closely next year.

Thanks to all the loonwatch volunteers for their monitoring efforts.
Loonwatch volunteers – please sign and mail in your volunteer hours forms. Gracias.

Upcoming events:
Movie: The Darkside of the Loon (about wintering loons and loon threats in the winter)
-Thursday, 6 August, 7 pm, River Arts Building, Morrisville, VT
-Early September, Montpelier, Location and Date to be determined soon

Loon Program and Slideshow – 15 August, 2 pm, Branbury State Park, Lake Dunmore, Salisbury, VT (fee for park).

Eric Hanson, VLRP Coordinator and VCE Biologist

New Study Indicates Benefit of Old Growth Forests for Wintering Monarchs

Survival of overwintering monarch butterflies following severe wet winter storms in Mexico is substantially higher for butterflies that form clusters on the oyamel fir tree trunks than for those that form clusters on the fir boughs.

Thermal measurements taken at similar elevations with a weather station on the Sierra Chincua and within a Cerro Pelon and a Sierra Chincua overwintering area indicated that clustering on the fir trunks provides dual microclimatic benefits for the butterflies.

At night, the minimum surface temperatures of all firs combined averaged 1.4 °C warmer than ambient forest temperatures, thereby enhancing protection against freezing for monarchs that are either wet or dry. We term this the 'hot water bottle effect.'

During the day, the maximum surface temperatures of all firs combined averaged 1.2 °C cooler than ambient, a difference sufficient to lower the loss of the butterflies' lipid stores over the 154-day wintering season.

Larger diameter trees increase both microclimate benefits. The results add a new dimension to improving the conservation management guidelines for the Monarch Butterfly Biosphere Reserve. Strict enforcement against culling of larger trees and in favour of promoting old-growth oyamel forests will enhance two microclimatic benefits: butterfly mortality during severe winter weather will be reduced, and the butterflies' lipid savings over the winter will be enhanced.

Oyamel fir forest trunks provide thermal advantages for overwintering monarch butterflies in Mexico
LINCOLN P. BROWER, ERNEST H. WILLIAMS, DANIEL A SLAYBACK, LINDA S. FINK, M. ISABEL RAMÍREZ, RAÚL R. ZUBIETA, M. IVAN LIMON GARCIA, PAUL GIER, JENNIFER A. LEAR, TONYA VAN HOOK
Insect Conservation and Diversity
Volume 2, Issue 3 , Pages163 - 175

Birdwatchers No Featherweights in Contributions to Economy

A new report released today by the U.S. Fish and Wildlife Service shows one of every five Americans watches birds, and in doing so, birdwatchers contributed $36 billion to the U.S. economy in 2006, the most recent year for which economic data are available. The report – Birding in the United States: A Demographic and Economic Analysis –shows that total participation in birdwatching is strong at 48 million, and remaining at a steady 20 percent of the U.S. population since 1996.

Participation rates vary, but are generally greater in the northern half of the country. The five top states with the greatest birding participation rates include Montana (40 percent), Maine (39 percent), Vermont (38 percent), Minnesota (33 percent) and Iowa (33 percent).

The report identifies who birders are, where they live, how avid they are, and what kinds of birds they watch. In addition to demographic information, this report also provides an estimate of how much birders spend on their hobby and the economic impact of these expenditures.

The report is an addendum to the 2006 National Survey of Fishing, Hunting, and Wildlife-Associated Recreation. The 2006 survey is the eleventh in a series of surveys conducted about every 5 years that began in 1955. The survey, conducted by the U.S. Fish and Wildlife Service in partnership with state wildlife agencies and national conservation organizations, has become the reference for participation and expenditure information on fish and wildlife recreation in the United States. The survey helps quantify how enjoyment of the outdoors and wildlife contributes to society and promotes a healthy economy – and further strengthens the Service’s commitment to conserve the nation’s wildlife for the enjoyment and benefit of the American people.

A copy of the Birding in the United States: A Demographic and Economic Analysis can be downloaded here:

http://library.fws.gov/Pubs/birding_natsurvey06.pdf

In conjunction with the release of the birding report, the Service also issued another similar addendum to the 2006 Survey entitled, Wildlife Watching Trends: 1991–2006 A Reference Report. This report shows similar trends in wildlife-watching, a broader category that includes large and small-mammal viewing.

An overview of the Survey, and a wealth of other information, can be found online at:

http://wsfrprograms.fws.gov/Subpages/NationalSurvey/National_Survey.htm

Bicknell’s Thrush Geolocator Quest on Mt. Mansfield

Needing 5 more adult male Bicknell’s Thrushes (BITH) on Mt. Mansfield to reach our target of 20 birds for attachment of solar geolocators, we returned last Thursday evening to our ridgeline study site. We knew it would be a stretch to capture that number on a relatively small area with challenging netting terrain, a number of net-wise birds, and the likelihood that males would be less responsive to playbacks than a month ago.

We arrived via the toll road in early evening, just as strong thunderstorms dumped heavy rains and peppered the ridgeline with lightning. Waiting it out, we quickly had > 20 mist nets set up by dusk, watching nervously as lightning continued to flicker around us, sometimes disconcertingly close. Avian activity was solid, but the dusk chorus of BITH and White-throated Sparrows was definitely reduced from June’s peak.



Our hunch was right. In fact, we didn’t come close to replicating our previous week’s success on Slide Mt. Although we captured 10 BITH overall, none were candidates for geolocators. We caught two already-geolocatored birds – one a 10-year old male banded as an immature in September of 2000 (the second oldest on record), the other a female we had guessed was a male back in early June (before she was in breeding condition) – plus 6 yearling males, and 2 other females. There was a surprising amount of vocal activity, both calling and singing, but birds were virtually unresponsive to playbacks, and most of our mist net captures were passive.

So, we’re “stuck” on 15 birds with geolocators on Mansfield, our mantra of “5 and out” unfulfilled. We'll make a last assault on those 5 males in mid-Sept, when there is a resurgence of BITH activity (including vocalizing) prior to southward migration. For the 2009 field season so far, we have mist-netted 30 BITH on the ridgeline – 10 adult males (2+ years old; 3 from previous years), 12 yearling males, and 8 females (4 previously banded). We’ve also captured 8 males at lower elevations in the Ranch Brook watershed and attached geolocators to 6 of them. Regardless of our success in September, we’re poised to make exciting discoveries next June, when we expect to recapture at least 8 or 9 of this summer’s 15 birds and recover the precious information held in their geolocators.

Sunrise on Mt. Mansfield after an evening of storms.

Vermont Loonwatch 2009 Needs You!

On Saturday, July 18th, over 200 citizen scientists will be paddling on or walking around Vermont’s lakes to assess the state’s loon population. Many waterways are still in need of volunteers to monitor loons between the hours of 8 and 9AM. Vermont Loonwatch is a great way to explore a new lake or spend a morning with family and friends while helping a bird species in need. All data collected during Loonwatch are entered into Vermont eBird to help determine the course of action needed to ensure the health of loons on our busy waterways.

Since 1983, many hundreds of volunteers have searched for these majestic birds on assigned ponds, lakes, and reservoirs from the Quebec border to the Massachusetts line. Once a state-endangered species, the loon has made a tremendous rebound in Vermont. The first Loonwatch in 1983 reported 29 adult loons. Thanks to the efforts of the VLRP and its corps of dedicated volunteers, the 2008 Loonwatch reported over 200 adult loons. Vermont’s loon recovery is truly one of the state’s conservation success stories.

If you would like to join Vermont Loonwatch as a citizen scientist, please contact Eric Hanson, VCE Biologist and Vermont Loon Recovery Project Coordinator at 802-586-8064 or ehanson (AT) vtecostudies.org.

Check out the lakes that need volunteers!

Entering loonwatch data? Read the quick tutorial for help.

Bicknell’s Thrush Bonanza on Slide Mountain

The VCE Bicknell’s Thrush (BITH) “A-Team”, a group of 4 grizzled veterans, returned to the birthplace of BITHnology this past week, ascending Slide Mountain in the Catskills’ during the early evening of July 8. We represented more than 50 collective years of BITH pursuit among us, and the setting couldn’t have been more appropriate. Almost exactly 118 years earlier, on June 15, 1881, Eugene P. Bicknell had encountered (and collected) the first known specimen of BITH on the summit of Slide Mountain. As we trudged up the 2.7-mile trail with bamboo net poles slung over our shoulders, backpacks full of mist nets and banding gear, we had to wonder how Mr. Bicknell would have looked upon our current quest. Quizzical head-shaking would have been one reaction, no doubt.

Our mantra of “9 and out” underlay the goal of capturing an additional 9 adult male BITH for attachment of solar geolocators, tiny light-gathering devices attached harmlessly as backpacks. This new dimension to VCE’s research on BITH promises to shed important light on the species’ migration patterns, as well as connectivity of discrete breeding and wintering populations. With collaborators in Canada, we have initiated a rangewide study that is attempting to attach geolocators to 20 males in each of six breeding areas: the Catskills, Mt. Mansfield in Vermont, 2 Quebec sites, and one site each in New Brunswick and Nova Scotia. Our first trip to Slide Mt. and nearby Plateau Mt. in mid-June had met with solid success – 5 birds on Plateau, 6 on Slide. Needing 9 to reach our goal of 20, we had planned a two-night backpacking venture across Slide, Cornell and Wittenberg mountains.

Reaching the Slide summit at 7:00 pm, we set 6 mist nets within a several-hundred meter radius before dusk descended, broadcasting recorded BITH songs and calls at each. Several birds responded, but none were caught. Our empty-handed disappointment was erased by a breath-taking moonrise as we returned to the 4180-foot summit just after dark.

Several hours later, we were back at it, opening our nets in the pre-dawn darkness and scampering to set up others. Dawn came slowly through the fog-filled valleys below, with Hermit and Swainson’s Thrushes the morning’s first avian voices. As we clicked on our iPods, CD players, and small cassette recorders, the nasal “beeer” calls and spiraling songs of BITH filled the air. And, our nets began filling with birds…

The following 6 hours were epitomized by Brendan Collins’ half-elated, half-frantic shout at 5:30 am, as he sprinted back to our banding site, “I’ve got 5 thrushes in a net!”. We literally experienced an inundation of BITH, capturing no less than 19 individuals by the time we closed our last mist net just before noon.

During > 15 years of studying the species, none of us had ever seen anything like this. We shattered our goal of 9 adult males, attaching geolocators to 11, 3 of which were birds our colleague Jason Townsend had banded on Slide last summer. We caught one male from our mid-June trip, its geolocator and body condition in fine shape. We also netted and banded 4 yearling males and 3 actively-nesting females. It was an exhilarating morning, to say the least!

Having exceeded our “9 and out” goal by two, we hiked back down in early afternoon, marveling at Slide Mountain’s dense BITH population, the extent and integrity of its balsam fir habitat, and hopeful that we had somehow done E.P. Bicknell proud. Stay tuned for an update in 2010, when we return to recapture those geolocators and recover the priceless data they hold.

WHITE NOSE SYNDROME AFFECTS N.H. BATS THIS SUMMER; PETERBOROUGH COLONY DECIMATED

CONCORD, N.H. -- The deadly White Nose Syndrome (WNS), a new disease affecting hibernating bats throughout the Northeast, appears to be affecting bats in New Hampshire this summer. Hundreds of thousands of bats have died over the past three years in states from New Hampshire to Virginia. A bat colony in Peterborough has sustained a catastrophic level of deaths, and reports have come in from several New Hampshire towns about young bats dying.

Biologists from N.H. Fish and Game's Nongame and Endangered Wildlife Program and all across the region are involved in tracking WNS, which was discovered just three years ago and appears to be nearly always fatal to bats. Affected bats usually have a characteristic white fungus on their muzzles, wings and tails, but only in the caves and mines (hibernacula) where they spend the winter. The bats use up their stores of body fat, which is all they have to survive the winter, become emaciated and die. Hundreds of thousands of little brown bats and five other species have died, from New Hampshire to Virginia.

"Since so many bats have died, we expected to see declines in some maternity colonies," said New Hampshire Fish and Game wildlife biologist Emily Brunkhurst, "But the other effects we have seen have been surprising and sad."

Dr. Scott Reynolds has been studying a maternity colony of little brown bats in Peterborough, N.H., for over 15 years. It is the longest-running study of these colonies, where female bats gather under the roof of a barn or attic, where it is nice and hot, to bear and raise their pups. Each female normally gives birth to just one baby. After banding more than 4,000 bats over the years, and despite knowing that some of his banded bats were found dead of WNS in hibernacula in Vermont, Reynolds was still shocked to discover how WNS had devastated this colony. "I expected a decline, as there were 20% fewer last year than there had been before," he said, "but this year there are almost no bats; the colony is functionally gone."

The Peterborough colony has averaged about 2,000 bats over the last 15 years, and has been in existence for at least 40 years. There are now fewer than 100 bats left, and they have lost the advantages of a big colony. "Bats save a lot in energy by clustering together, passively maintaining a high body temperature," says Reynolds. "Now they need to spend a great deal of their energy budget on heat, and thus have a reduced growth rate. This spring the pups seemed to be healthy and growing fast, but they have now all disappeared. We don't know what happened."

Brunkhurst said, "When I heard of the loss of the Peterborough colony, I was shocked. We all understood that thousands of bats had died, and that the possibility was there that we would see great losses, but this just brings home the possibility, or maybe likelihood, that our summer skies will soon be fairly devoid of bats." Already Fish and Game has received many calls and emails that ponds once busy with bat activity, and barns where bats had traditionally roosted, are empty.

One surprising effect is that female little brown and big brown bats are abandoning their pups in greater numbers than ever before, according to Brunkhurst. One barn in Amherst, N.H., had over 16 babies come down, and, although 13 were rescued and taken to a wildlife rehabilitator, all died. This is also true of barns in Durham, Epsom, and Dunbarton, N.H., as well as colonies in Vermont, Connecticut, Virginia and other states. Susi von Oettingen, biologist with the US Fish and Wildlife Service (USFWS) said, "I'm puzzled by the unexpected pup mortality. Our preliminary observation is that the pups are emaciated, but we do not know if this is an effect of WNS or of the wet weather or some unknown cause." Dr. Reynolds plans to look at his long-term data to predict what mortality such a wet spring would be expected to produce, and compare it with the actual numbers to see what the effect of WNS might be.

New Hampshire. Fish and Game has teamed up with Vermont Fish and Wildlife to collect information on sick bats. If you find a dead bat this summer, or notice the absence of bats where they typically are seen in abundance, report it on the online reporting form hosted on the Vermont Fish and Wildlife website: http://www.vtfishandwildlife.com/Sick_Acting_Bat_Citizen_Reporting_Form.cfm.

Researchers have been working hard to learn as much as possible about this disease, but there has not been enough funding to get everything done. So far they have discovered that the fungus on the bats is new to science. It has been aptly named Geomyces destructans by its discoverer, Dr. David Blehert and his colleagues. It is not known whether the fungus causes the bats to become emaciated during the winter, or if something else is killing the bats.

Recent funding through the USFWS State Wildlife Grant Program has provided some resources for states to respond to this problem through monitoring of bats, and research and management of bat habitat, especially the hibernacula. Response to a Nongame Program special appeal last fall provided donations that funded surveys of caves and mines in New Hampshire for WNS last winter. A new USFWS grant will fund research into mortality, disease spread and containment or population effects of WNS. Some possible projects include discovering if known treatments for fungal diseases can control WNS, finding ways to build resistance to the disease in bats, understanding the population effects of WNS and searching for causes other than the fungus. Several New Hampshire bat researchers are involved in projects to help in learning more about and controlling WNS. Congress has recently taken an interest in this fast-moving problem, but there has been no additional funding forthcoming as yet.

Meanwhile, one of the traditional sights of summer may be less visible in New Hampshire this year. "The little brown bat - the one most affected -- is the bat we often see cruising over a pond, eating insects," Brunkhurst said, "Bats eat thousands of pounds of agricultural pests and nuisance species like mosquitoes every summer. It is very alarming to think how this huge drop in the bat population will ripple through the ecosystem, and possibly affect our food production and timber industries."

Giving a loon a second chance

WCAX Channel 3 news will cover this story tonight on its 6pm evening broadcast

Loons are a beautiful, high profile species, and when they are in trouble, our instinct is to help. When I received a call the other day from a woman claiming to have a loon in her tiny man-made pond, I deliberated about whether to rescue it.

As the only group of bird species with solid bones, loons need a quarter mile of open water to become airborne. A tiny pond is a death trap. Just like airplanes, in bad weather loons sometimes have emergency groundings that place them in odd locations, and that is likely what happened to this particular loon. Although it was happily feasting on the woman's stocked yellow perch (she took it well), without a way to leave the pond, it would eventually die.

We tend to let nature take its course for loons that are injured in territorial battles. But this loon appeared healthy, and a relocation to a nearby, large lake would likely ensure its survival. It was stuck on a man-made lake, so I decided it was appropriate to set it on a more natural course.

The capture was a great success, and received local media attention, as wildlife rescue stories often do. WCAX news will air the story on its 6pm broadcast tonight (Wednesday). But what matters most for loon conservation is not the rescue of individuals.

What is important for loon conservation is to protect nesting habitat on the shorelines and islands of our lakes and ponds, to keep waters free and clear of mercury, invasives, and fertilizers, and to leave nesting loons and chicks undisturbed.

Humans have been largely responsible for the loon's remarkable comeback here in Vermont and elsewhere, thanks to nesting platforms, outreach, and a reduction in the use of lead sinkers. With support from Vermont Fish and Wildlife Department's Nongame and Natural Heritage Program, the Vermont Loon Recovery Project continues to monitor loons through an extensive citizen science volunteer network. If we extend our passion for protecting individual loons to protecting their habitat, the species will continue to thrive.

- Rosalind Renfrew

Visitors Travel from Afar to See a Bicknell's Thrush

The VCE Bicknell’s Thrush team recently introduced two of our Dominican counterparts to the songbird that has formed a bridge between our two countries since VCE began studying the species on Hispaniola in 1994. Jesus and Jaime Moreno, ardent Dominican conservationists, co-owners of the country’s top-selling ice cream company, Helados Bon http://www.heladosbon.com, and VCE partners in the DR, visited our study site on Mt. Mansfield on June 29-30. The primary object of their quest was Bicknell’s Thrush itself, a bird that has coalesced our collaborative conservation efforts in the DR but also eluded their previous attempts to find it on the island. We had guaranteed them an up-close-and-personal encounter here in Vermont, so the pressure was on, especially with a threatening forecast for Monday and Tuesday.

As we began ascending the Mansfield toll road about 7:30 pm on Monday, clouds magically lifted and patches of clearing skies appeared. Winds were calm on the ridgeline, temperatures mild, and hopes high as we set up several mist nets. Our attempts to capture a thrush with recorded playbacks were unsuccessful that evening, but we treated our visitors (which included colleagues Jamie Phillips of the Eddy Foundation and Chuck Kerchner of AgRefresh http://www.agrefresh.org) to a stunning view of Lake Champlain and a strong dusk chorus. We practically had to drag Jesus off the mountain after dark…

The following morning featured a different story weatherwise, as clouds had descended on the mountain and winds picked up from the south. However, we opened our 7 nets at dawn and awaited our visitors, who had stayed below at the Stowe Mountain Resort. We quickly caught 4 thrushes, one of which received a new solar geolocator, but we dared not hold them in the cool, wet weather. Luckily, Jesus, Jaime, Jamie, and Chuck appeared shortly after 6:00 am, in time to see a newly-captured male and female thrush. It was an exciting and rewarding moment for all, and Jesus proved an avian Pied Piper, as the male sat in his hand for a full minute before flying off. We mist-netted one more female (a bird banded in 2007), putting our morning’s total at 7 birds in 7 nets.

Breakfast in Stowe found us all planning for future collaborations in the Dominican Republic, where we are beginning an ambitious 2-year, multi-partner conservation project in the Cordillera Septentrional. Once again, the Bicknell’s Thrush had proved to be a bridge between two countries and two cultures, each with equal responsibility for ensuring its long-term conservation.