Tag Archives: birding

A Plethora of Pirates: Jaegers rule at Provincetown

First it was shearwaters—now it’s jaegers!

Earlier this fall the waters off Provincetown made news when an unprecedented concentration of thousands of Great Shearwaters was attracted inshore by a superabundance of small menhaden fish (a.k.a. peanut bunker) that were driven ashore by foraging mackerel. This influx afforded birders, fishermen, and the general public a unique opportunity to see these normally open ocean seabirds at practically arm’s length.

Now, several weeks later, exceptional numbers of jaegers have taken center stage in these same waters.  Dusky-colored and predatory, jaegers are gull-like seabirds that in North America nest on high latitude arctic tundra from Alaska to Labrador. Taking several years to mature and exhibiting high variability and a complexity of plumages, jaeger identification can confound even the most experienced observers.

Parasitic Jaeger (dark morph) © Peter Flood

Meaning “hunter” in German, the word “jaeger” (pronounced “yay-ger”) is well-suited to three closely related species—Pomarine, Parasitic, and Long-tailed—all distinctive in adult plumage because of two, long, pointed or twisted central tail feathers.  But far more exciting is the kleptoparasitic lifestyle of jaegers.  Kleptoparasites are species that obtain much of their food by stealing it from other species, which in the case of jaegers usually means smaller seabird species such as terns.

A Parasitic Jaeger pursues a Common Tern © Peter Flood

Parasitic Jaegers are the new rulers of the waters off Provincetown

In Provincetown it is Parasitic Jaegers that have been maintaining dominion over the hapless terns lingering off Race Point in recent weeks.  Literally dozens of jaegers are currently tracking the hard-working terns off Race Point, the ever vigilant pirates constantly on the lookout for terns carrying fish in their beaks.  Upon spying a fish-laden victim, a plundering jaeger will at once give aggressive chase. With fighter plane-like precision, one or more jaegers will pursue a target with aerial gymnastics hardly seen in any other bird species.  So skillful at piracy are jaegers that they are often able to catch a falling fish relinquished by an intimidated tern before the fish hits the water!

A Parasitic Jaegar prepares to catch relinquished fish © Peter Flood

In the days ahead as the last of the lingering terns head for South America for the winter, the aerial pirates that have been recently harassing them off Provincetown will begin to drift away, shadowing the terns all the way to their South Atlantic wintering quarters.  Although Parasitic Jaegers are capable of capturing fish or scavenging food on their own, during their non-breeding season at sea they generally prefer their criminal life style as a way to obtain food.  Come spring however, the jaegers will head north for their arctic nesting grounds where their diet will shift to small rodents or shorebird eggs and chicks.

Always predatory and always on the move, jaegers are fascinating seabirds that can only be admired when viewed in full pursuit of a fleeing tern, or when observed deftly flying amid the frothy troughs of a storm-tossed sea.

Get to P-town soon to see these spectacular birds for yourself!

Parasitic Jaegers pursue a tern © Peter Flood

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Flight of the Broad-wing: an epic in the sky

Every year, at about this time, dedicated hawk watchers and serious raptor aficionados begin paying particular attention to radar images and weather prognostications on the evening news. Indeed, some devotees even regularly take their vacation in the middle of September. So what’s so special about mid-September? To those in the know with an interest in hawk migration, mid-September is THE time to intercept the peak southward departure of the Broad-winged Hawk (Buteo platypterus).

Adult Broad-winged Hawks are 15 inches-long with a 24 inch wing-spread, a black tail crossed midway with a single wide, white band, a brown back, and rusty-brown underparts.  In flight they are compact, with broad wings that are pale underneath and traced with a thin black border around the edges (as shown in the above photo). Ranging throughout most of the eastern United States and southern Canada west to Alberta, Broad-wings spend much of their summer hunting amphibians, snakes, small mammals, and birds to feed their young.  However in mid-September it is the spectacular autumn migration of this species that annually captivates and mesmerizes hawk watchers, and often even the general public as well.

Unlike other raptors (or most other species of birds for that matter) few have such a telescoped seasonal departure as the Broad-winged Hawk. With seemingly mathematical precision, much of the North American breeding population typically initiates its southward migration sometime between September12–20.  Depending upon weather conditions, in some years this time window becomes even more compressed, occasionally with many thousands of individuals passing favored observation sites literally within a few hours. Here in Massachusetts, Wachusett Mountain in Princeton, Mt. Watatic in Ashburnham, and Mt. Tom in Holyoke are among the better places to witness this phenomenon.

In mid-September Broad-wings across much of their breeding range wait strategically for the passage of cold fronts accompanied by falling temperatures and light winds from the north side of the compass to begin their migration.  Under such conditions the hawks almost simultaneously begin lifting up from the summer woodlands where they nested to search for rising warm air masses called thermals that will help eventually transport them to South America for the winter.

Using such thermals to carry them skyward many thousands of feet, eventually the Broad-wings break out of the thermals and travel to another thermal, often several miles away, by means of long, high-speed power glides that cause them to gradually lose altitude at the same time.  Once they reach another thermal, they then ride the new “escalator” skyward. Because hundreds of Broad-wings are using this same strategy, on a good day for migration, a large thermal often contains many hundreds of tightly soaring individuals all rising upwards at the same time.  In hawk parlance such an aggregation is called a “kettle” (shown below).

On days favorable for migration, many thousands of Broad-winged Hawks make their way southward at the same time using this combination of riding warm air thermals upward for lift, and then power gliding to another thermal so they can regularly cover hundreds of miles a day under ideal conditions. The migration tends to follow the southwesterly leading line created by the Appalachian Mountains. Between the thermal-and-glide strategy, and wind lift created along Appalachian ridgetops, the hawks gradually make their way to the Gulf Coast, where they gradually “turn the corner” in southern Texas to avoid crossing the Gulf of Mexico, and then make their way into Mexico and south through Central America, and finally into northern South American where most will spend the winter.

Not surprisingly there are variations in this strategy along the way, including several world-famous hawk-watching bottlenecks where, with several other species, they pass through Mexico, Costa Rica, and Panama.  While this is by no means the full story, it is the essence of how each year this magnificent raptor accomplishes one of the most amazing autumn migrations in the western hemisphere.

 

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Hot Off the Press! State of the Birds 2017

Black-capped Chickadee may face an uncertain future in Massachusetts. ©Bill Thompson, USFWS

It is with great pleasure that we announce that our third edition of State of the Birds is now available. State of the Birds: Massachusetts Birds and Our Changing Climate focuses on what the future may hold for the breeding birds of Massachusetts as the climate continues to change.

Our last two State of the Birds reports, released in 2011 and 2013, compared the past to the present and identified changes in Massachusetts bird populations. The 2017 edition builds on that work by using science to predict the future.

Climate Matters For Birds and People

Most birds have limited distributions and, to some extent, climate controls the range of those distributions. To glimpse the future, we used a statistical analysis called climate envelope modelling.

Put simply, climate envelope modelling uses real bird and climate (various measures of temperature and precipitation) data to define the preferred climate of a bird species—their “climate envelope”—as it is today. Then the models substitute predicted values of the climate variables into the equation to project a bird’s climate envelope in 2050.

Using the results of our analysis, we assigned each of the 143 species analyzed a “Climate Vulnerability” score. There were some expected results and some surprising results. The overarching message was that birds are already feeling the effects of climate change and even some of our most common birds will probably experience further changes by 2050.

It’s In Our Power to Change the Future

While climate change can feel like an overwhelming problem, it is a problem that we can solve. Much like Scrooge in A Christmas Carol, we are being shown a possible future for our birds, and, just like Scrooge, we can take action today to change that future.

Visit the website, download the report, and share it with your friends and family. If we work together we can protect birds, wildlife, and ourselves.

Check out the article in the Boston Globe about the State of the Birds report.

Please consider supporting our bird conservation work by making a donation today. Thank you!

Beachfront Armageddon: A fish tale and a seabird saga

For several weeks the sandy beaches at Race Point and Herring Cove Beach in Provincetown have witnessed a spectacular and practically unique confluence of seabirds and fish.  The players in the P-town saga have been Atlantic menhaden (Brevoortia tyrannus) and Great Shearwaters (Ardenna gravis).

Great Shearwaters are Ring-billed Gull-sized seabirds that maintain their breeding terminus at Tristan de Cunha, a remote archipelago located deep in the southern hemisphere approximately halfway between the tip of southern South America and Cape Horn in South Africa.  Annually most of the world’s population of Great Shearwaters migrates north across the equator to spend the austral winter in the northwest Atlantic Ocean. By late summer most of the adult population has begun the long return journey back to Tristan du Cunha to nest, but the non-breeding sub-adult population regularly remains in North Atlantic waters until late fall.  While in the northern hemisphere Great Shearwaters typically remain on remote fishing banks far off the New England and Atlantic Canadian coasts where they forage on baitfish such as sand lance, capelin, sea herring, or squid and fish bycatch obtained by tracking commercial fishing vessels.

Each high tide left behind a swath of dead menhaden.

Menhaden are a super-abundant forage fish often characterized as one of the most commercially important fishes occurring along the Atlantic coast of the United States, particularly from Massachusetts to the Carolinas (Bigelow and Schroeder’s Fishes of the Gulf of Maine, Collette & Klein-MacPhee, eds., Smithsonian Press, 2002).  Due to their super abundance, immature Menhaden typically less than 2” in length are important fodder for a variety larger predatory fish, marine mammals, and seabirds.  For reasons not always clear, the literature suggests that they are periodically subject to mass late summer stranding and mortality events. These mortality events most often occur in shoal water habitats such as the heads of tidal creeks or small coves like the Herring Cove area in P-town where they may suffer from oxygen depletion or are driven ashore by predators (op.cit.).

Regardless of the explanation, a massive menhaden mortality event took place during the last couple weeks of August and early September.  Most notable however was the fact that unprecedented numbers (i.e., many thousands!) of Great Shearwaters appeared inshore to feast on the abundant fish.  For many days in a row, on each falling tide the voracious shearwaters literally swarmed in the surf picking off the tiny fish like popcorn. For a normally completely pelagic species that spends most of its life out of sight of land, this behavior was most unusual and provided birdwatchers, fisherman, and beach-goers a rare opportunity to observe these interesting seabirds at literally pointblank range!

Check out this video to see what this phenomenon looked like.

 

How birds sing such intricate songs

The colorful bursts of flowers and the familiar smell of thawing soils that we all associate with spring is always accompanied by the wonderful sound of bird song.  There is nothing quite like waking early enough to experience the dawn chorus, where male birds, representing a slew of different species, are persistently singing to secure a breeding territory and attract a mate for the season.

Wood Thrush © Sheila Carroll

The beauty and complexity of these songs is attributable to a unique organ that most birds possess, called a syrinx.  Located where the trachea – commonly known as the windpipe – splits into the bronchial tubes before entering the lungs, the syrinx has two symmetric halves, each capable of producing sound independently.  This enables songsters to make seamless changes in pitch, articulate a complex burst of short notes, and even sing two tones at once.

Some of our most impressive singers are the thrushes.  This family (Turdidae) includes species such as the American Robin and Eastern Bluebird, but perhaps the most impressive singers are those which inhabit deep forests.  Some of these songs, such as the Wood Thrush’s and Veery’s, are featured on the following website, where you to listen at regular speed as well as slowed down:

http://www.wildmusic.org/animals/thrush

When you slow the songs down you can really hear the intricacies.  Put some headphones on to really have a close listen, and maybe you will have a fuller appreciation the next time you hear a bird singing.

Please consider supporting our bird conservation work by making a donation today. Thank you!

Standing Together for Migratory Birds

By Jeff Ritterson, Bird Conservation Fellow

On Tuesday, May 9th, I was in Washington D.C. at Standing Together for Migratory Birds—a legislative briefing on federal migratory bird conservation programs.  With recent political changes in Washington, it may seem that support for these programs, and the crucial funding they provide, is on the chopping block.  But that’s not necessarily the case, and here’s why.

As conservation biologists, we understand that humans are inextricable from natural world, and that healthy and functioning ecosystems are inherently good for us.  However, we also understand that money talks, and this was a theme of the legislative briefing.  In remarks given by Senator Whitehouse (Dem-RI), he stated that, more often than not, humans come first on Capitol Hill, and every last issue gets monetized.

With that in mind, the American Birding Association presented on the economics of migratory birds and wildlife watching.  For example, the U.S. Fish and Wildlife Service reports that in 2011 Americans spent about $15 billion on birdwatching trips and an additional $26 billion in related gear.  A presentation by Ducks Unlimited also showed that significant money is spent hunting waterfowl, and 98 cents of every dollar from federal duck stamps sales goes to the acquisition of habitat—more than 6 million acres since its inception in 1934.

Of course, these activities depend on the conservation of our migratory bird species, and that’s where federal programs come in.  For example, since 2002 the Neotropical Migratory Bird Conservation Act has provided about $60 million to fund over 500 migratory bird conservation projects.  Also, the Farm Bill funds conservation programs that successfully help agricultural producers and migratory birds.  For example, thanks to these programs, Whooping Cranes are now nesting in Louisiana farmland – the first state nest in 75 years.

However, it’s not just a federal handout.  Many programs require additional contributions—as much as 3 dollars for every 1 federal dollar provided.  This way programs stimulate conservation activity and non-federal support from sources such as private foundations and donors.

With such a sound economics, federal migratory bird conservation programs can receive support from both sides of the political aisle.  That said, they are periodically reviewed, and it is important to tell your senators and congressional representative that you support full funding of bird conservation programs.

 

Please consider supporting our bird conservation work by making a donation today. Thank you!

What is it like to participate in Bird-a-thon?

Bird-a-thon, Mass Audubon’s largest annual fundraiser, features a 24-hour team birding competition where birders and team supporters raise money to support Mass Audubon programs and sanctuaries. What is it like to be a part of Mass Audubon’s Bird-a-thon? Michael Pappone, longtime member of the Bird Conservation team and Mass Audubon board member, shares his experiences from Bird-a-thon 2016:

“My team is up by 3:30 a.m. to gather well before dawn at the Bolton Flats Wildlife Management Area in Worcester County. The mist lurks around the cat-tails and willows. The Eastern Phoebe’s ‘vree-bee’ call rings out in the near distance (check!), and then the ‘oonk-a-dunk’ of the endangered American Bittern crouching somewhere out there in the wetness signals that it was time for another (check!) and that it is going to be a great day in the field. Then suddenly a Sandhill Crane floats by. Is he mistaking the Worcester County wetlands for Nebraska? Big (check!).

Bird-a-thon is in full swing! Behind us, a Scarlet Tanager let loose with his robin-with-a-sore-throat imitation. (Check!) At this rate our palms will be smarting from all the high-fiving before sunrise. Over at the sandy end of the Flats, another endangered fellow greets us from the heights of his very own 3-foot shrub sticking out of the sandy soil: a Grasshopper Sparrow, sounding very much like a grasshopper that just touched a high-voltage wire. With about 40 check marks on our list, we obey the law of diminishing marginal returns and split for new territory.

Next stop is Wachusett Mountain, where our ascent is rewarded with not only a good number of (checks!) but amazing numbers of Ovenbirds (teacher-Teacher-TEACHER!), Scarlet Tanagers, and Black-and-White (te-tsee te-Tsee-Te-TSEE) and Black-throated Green Warblers vocally squabbling over territory. The (non-check!) bonus is the sighting of a few remaining snow patches. Really good ‘gets’ here are the Yellow-bellied Sapsucker and Winter Wren. The last of the Dark-eyed Juncos has favored us with a delayed trip north just so we could be the team who gets to count him. Nice.

It’s on to the Quabbin Reservoir: a totally new venue for me out in Hampshire County. The reservoir was formed by a dam built in the Depression years from 1930-1939. The public works project flooded a number of communities to make way for 420 billion gallons of water and a new 181 miles of shoreline. It’s a big hit with the birds, that’s for sure. We revisit a number of previous species – in broad daylight this time; and notch a good number of new ticks on our checklist.”

©Michael Pappone

Join the Bird Conservation team as either a Booster or an Official Birder!

2016-2017 Christmas Bird Count Summary

Ross’s Geese have been seen more often in Massachusetts in the last few years © Aaron Maizlish

The last issue of The Warbler provided a brief history of the venerable Christmas Bird Count (CBC) – a scheme established in 1900 to monitor winter bird populations during a three-week period around Christmas.  This issue offers a few Massachusetts highlights from the 2016-2017 CBC season.  In checklist order, waterfowl made a big splash this winter with rarities such as Pink-footed Goose, Greater White-fronted Goose, Ross’s Goose, and Cackling Goose variously honking things up on several counts, along with some mega-numbers like 17,629 Black Scoters on the Truro CBC, 33,054 Long-tailed Ducks at Nantucket, and a state-wide total of 2,231 Hooded Mergansers.  Several “chickens” continued a downward trend with only 13 Northern Bobwhites tallied on one count, and a state-wide total of 12 Ruffed Grouse on only 6 CBCs.  Compare these figures with the state total of 2,273 Wild Turkeys!

Vultures continued maintained a northward shift in winter numbers (possibly a climate change signal) with a total of 19 Black Vultures noted on just two counts, and 133 Turkey Vultures on 8 CBCs.  A rare-in-winter Osprey appeared in Truro, and state-wide, 219 Cooper’s Hawks maintained their seasonal dominance over the 138 recorded Sharp-shinned Hawks.  In the unobtrusive category, a Yellow Rail recorded at Nantucket was most unusual, and a total of 255 Lesser Black-backed Gulls on that same island speaks to how rapidly this Old World species is moving into North America.

A heavy fall flight of Northern Saw-whet Owls was no doubt responsible for tallies of 45 Saw-whets on the Concord CBC and 30 in Truro.  Two White-winged Doves in Boston’s Victory Gardens and a hardy Rufous Hummingbird on the Buzzards Bay CBC were unique this CBC season. Falcons reflected varying success, with the beleaguered American Kestrel state total of only 13 individuals continuing a disappointing downward trend, while cumulative totals of 37 Merlins and 34 Peregrine Falcons can only be described as optimistic.

Several bona fide rarities included an Ash-throated Flycatcher on the Mid-Cape Cod CBC, a Sedge Wren at Buzzards Bay, and a Townsend’s Solitaire at Cape Ann.  And for any readers who think that American Robins are only harbingers of spring, consider a total of 35,125 robins on the Mid-Cape CBC and the state-wide total of 53,300!

Late lingering can only explain the occurrence of an Ovenbird, a Northern Waterthrush, and a Black-throated Green Warbler at three different localities.

While this summary speaks only to some of the highlights gleaned from this season’s CBC, full details and more information will soon be available at the CBC website.