Barn Swallows Successfully Return to Nest at Conte National Fish and Wildlife Refuge

Barn Swallows build their nests out of mud often on the eaves, rafters, and cross beams of barns, stables, and sheds.

Last summer, Mass Audubon’s Director of Bird Conservation, Jon Atwood, collaborated with Andy French, project leader at the Silvio O. Conte National Fish and Wildlife Refuge, to study Barn Swallows that were nesting in an aging horse stable destined for demolition during the non-breeding season. Approximately 40 pairs of swallows nested in the stable during 2019; an additional 4-7 pairs nested in an adjacent building, known as the Boat House, which the US Fish and Wildlife Service (USFWS) planned to set aside as a more long-term Barn Swallow nesting site and storage area. The aging horse stable was eventually demolished after the resident swallows had migrated to their South American wintering grounds.

The Barn Swallows are back!

We have good news to report! As hoped, the majority of swallows that nested in the stable in 2019 have returned and set up housekeeping in the Boat House. As of June 16 (still relatively early in the breeding season), 30 pairs were actively nesting in the Boat House, and four additional pairs had established nests in nearby artificial structures built for this purpose.

Jon Atwood removes a captured Barn Swallow from a mist net for banding.

Last year Jon banded many (but not all) of the Barn Swallow adults so that we could tell if they returned to the site in future years. Of 51 birds that have been captured using mist nets in the Boat House in 2020, 22 (43%) had been banded as adults in 2019 in the stable. In other studies, researchers have found that return rates of breeding swallows to undisturbed nesting sites have ranged from 20% in Oklahoma to 42% in New York. Although most Barn Swallows do not return to where they were hatched, we have even captured 2 individuals that hatched from nests that were located last year in the horse stable.

A new kiosk gives an up close look at the birds

Conte Refuge visitors watch nesting Barn Swallows at the kiosk at Fort River (photo by Andy French).

USFWS has placed video cameras in the Boat House, and visitors can watch the nesting swallows feed their young from an observation kiosk located near the start of the 1.2 mile long universally-accessible Fort River Birding Trail. Visitors may also be greeted by the families of Tree Swallows and Barn Swallows that are also nesting in the kiosk. The kiosk will eventually house a professionally-designed and fabricated exhibit with information about aerial insectivores.

This success will lead to other successes going forward

Not only does this success story provide a happy ending to the difficult management debate that swirled around the U.S. Fish and Wildlife Service’s decision to remove the horse stable, but these efforts have also paved the way for future conservation actions that can be applied to other situations. Aging barns occupied by Barn Swallows are a common feature in New England’s historically agricultural landscape, and sometimes these structures cannot be saved. Through the experience at Conte Refuge we have learned important lessons about how to attract and relocate Barn Swallows into alternative structures where they can be protected if occupied barns need to be removed.

We’ll keep you posted as the season progresses.

Historic Warbler Fallout and Record Bird-a-thon Participation

Warblers seemed to rain from the sky during Bird-a-thon 2020 after unusual weather doused Massachusetts in migrants. Birder participation more than doubled, too, but not because conditions predicted a massive influx of birds. Instead, it seems that more beginners were brought in by a family-friendly approach and a focus on birding from home.

Birds were everywhere

As the sun rose on the Outer Cape on May 16th, thousands of birds gathered in the dunes after being blown in from the southwest and grounded by rain. The subsequent dawn flight became the subject of several expert articles, including an in-depth analysis of the conditions by ornithology professor Sean Williams. Some eBird checklists recorded over 100 Bay-breasted and Cape May Warblers, plus dozens of individuals of other uncommon migrants like White-crowned and Lincoln’s Sparrows.

Inland, the action was almost as good, with several Bird-a-thon-ers in dense suburbs and towns setting personal records for their yards. Nonstop north winds had held birds back for nearly two weeks, and when the wind finally turned southwest, restless migrants pushed ahead despite the storms. Nearly everything showed up at once; yard reports of Cerulean Warblers, Bay-breasted Warblers, and Bobolinks highlighted the strength of the previous night’s migration.

“Fallout” may be an overused term– but this was real

The word “fallout” often gets misapplied to any day with really good migration. In reality, even in the loosest sense, this word refers to exhausted migrants that land in adverse weather. In the strict sense, it describes a stream of migrants that are knocked down by fast-moving storms, landing en masse when they meet the edge of the weather front.

In this case, adverse weather formed well before nightfall, but the long-delayed migrants pushed ahead anyway—there was no “knockdown” effect from the edge of a front, but the wind and rain did exhaust many birds that were blown east into Massachusetts. So, yes, this was a fallout, loosely speaking—and a uniquely great birding day by any stretch of the imagination.

New birders drove up participation

A normally competitive endeavor, this year’s Bird-a-thon focused on participation.The team cap was lifted, and new activities were made up to engage kids and non-bird enthusiasts in earning points for their team, like inventing silly bird names and creating bird art.  With a stay-at-home order driving a surge in interest in birding, it was important to welcome new enthusiasts to the fold– and avoid encouraging birders to tear across the state in search of rare species. Subsequently, Bird-a-thon attracted 1,600 participants this year, more than double the 750 who took part in 2019. 

Donations were up, too

As of right now, Bird-a-thon raised over $295,000 – far surpassing the $250,000 goal. Despite the current economic hardships of the coronavirus pandemic, these funds are up from the $240,000 raised last year.

The final tally

In total, Mass Audubon teams saw 242 unique species in Massachusetts. Teams were awarded points based on the number of unique bird species the team saw plus the number of nature-based activities team members completed. Drumlin Farm took first place with 992 points and a team of 230 participants (including 90 kids), earning the “Eagle Eye Award.” Second place, for the “Home Habitat Award” went to Wellfleet Bay with 537 points. The team from Ipswich River took home the award for the highest number of species seen: 206.

For a full recap of the incredible birding day participants shared, check out local birder and documentarian Shawn Carey’s video on the experience, complete with teammate interviews and great bird footage.

What We Like to Watch, Read, and Listen to About Nature

As our science staff have been spending more time at home, they’ve been reminded of all of their favorite nature-themed videos, podcasts, radio shows, tv shows, movies, and books, and have found new ones to enjoy as well. Check these out when you find yourself needing something to do.

Podcasts and Radio Shows

  • Ologies: Each week science correspondent and humorist Alie Ward sits down with a professional “-ologist” to ask smart people stupid questions. Episodes range across a wide variety of topics from ornithology (birds), mycology (fungi), and chiropterology (bats), to topics you may have never known existed like ferroequinology (trains) and vexillology (flags)!
  • Wild Ones Live: Mass Audubon’s Director of Conservation Science, Jeff Collins, heard this late one night driving home from the airport, and says, “it’s the strangest, most hopeful audio experience about wildlife conservation.” Author Jon Mooallem, performs excerpts from his book “Wild Ones: A Sometimes Dismaying, Weirdly Reassuring Story About Looking at People Looking at Animals in America” with musical accompaniment.
  • The Natural Experiment: An episode from 99% Invisible about how the COVID shutdown is opening opportunities for scientific research (ex: listening to humpback whales without the sounds of boats competing)
  • Living on Earth: Living on Earth with Steve Curwood is the weekly environmental news and information program distributed by PRX. The show is located at the School for the Environment at UMass Boston.
  • Ray Brown’s Talkin’ Birds: Talkin’ Birds is a live and interactive radio show about wild birds and the beauty of nature. Their mission is to encourage appreciation of our natural world and to promote the preservation and protection of our environment.
  • Mardi Dickinson’s Bird Calls Radio: a podcast with interviews of well-known birders on a wide range of birding topics and subjects.
  • Weekly Bird Report for the Cape and Islands: Mass Audubon’s Mark Faherty gives the weekly bird report for the Cape and Islands covering bird migration, unusual nest sites, and other interesting bird facts.
  • VCE’s Outdoor Radio: Our friends at Vermont Center for Ecostudies provide entertaining audio rambles through the forests, fields, and wetlands of our neighbor to the north. 
Jeff Collins, Director of Conservation Science, enjoys one of his favorite podcasts while keeping an eye out for birds.

Videos, TV Shows, and Movies

  • Round Planet:  If you like BBC’s Planet Earth and want to bust a gut laughing like the hyenas and kookaburras, check out this BBC show. Award-winning writers combine factually accurate comedy and incredible natural history footage to tell amazing stores of wildlife around the world.
  • Trees with Don Leopold– Always wanted to learn more about trees and how to identify them? Check out these short videos with Dendrologist Don Leopold as he introduces you to trees found in the northeast.
  • Learn How to Draw A Chickadee from David Sibley
  • True Facts About The Owl: Learn some fun facts about owls.
  • Stuff* Birders Say and Stuff* Nonbirders Say to Birders: birders and friends of birders alike will find these videos hilariously true. (*this is a replacement for another word starting with “S”)
  • Nature Moments: Nat Wheelwright, a Maine Audubon board member, has created a series of videos about the natural world.
  • Night On Earth: A docuseries that uses night-vision camera technology to show nocturnal wildlife around the globe (available on Netflix).
  • Dancing with Birds: A documentary that follows birds of paradise as they try to attract mates in elaborate ways (available on Netflix).
  • Our Planet: Experience our planet’s natural beauty and examine how climate change impacts all living creatures in this ambitious documentary of spectacular scope (available on Netflix).

Books

There are, of course, many books that we could recommend, but for now we’ve focused on a few that are available as eBooks since libraries and many bookshops are closed.

  • Birder murder mysteries by Steve Burrows: Director of Bird Conservation, Jon Atwood, has been enjoying these fun books lately as a way to relax!
  • Lab Girl by Hope Jahren: In this memoir, professor and geobiologist Dr. Hope Jahren beautifully weaves stories from her childhood and research to explore life as a woman in science, passion and curiosity, and the incredible secret lives of plants.
  • Wild by Cheryl Strayed: After her mother dies, 26-year-old Cheryl Strayed sets out to hike the Pacific Crest Trail with almost no experience. Based on true events from her journal, Strayed writes a story that puts you right alongside her on those 2,500 miles.
  • The Beak of the Finch by Jonathan Weiner: Two scientists, Peter and Rosemary Grant, have spent twenty years studying the finches of the Galapagos Islands and proving just how strong Darwin’s theory of evolution is.
  • Birding without Borders by Noah Strycker: Traveling to 41 countries in 2015 with a backpack and binoculars, Noah Strycker became the first person to see more than half the world’s 10,000 species of birds in one year.
  • A Natural History of the Senses by Diane Ackerman: Diane Ackerman’s lusciously written grand tour of the realm of the senses includes conversations with an iceberg in Antarctica and a professional nose in New York, along with dissertations on kisses and tattoos, sadistic cuisine and the music played by the planet Earth.
  • Golden Wings & Hairy Toes: Encounters with New England’s Most Imperiled Wildlife by Todd McLeish: A series of well-written and informative essays about creatures including, North Atlantic Right Whale, Bicknell’s Thrush, Indiana Bat, Golden-winged Warbler, Canada Lynx, Roseate Tern, and the Ringed Boghaunter dragonfly. 

ACT at Home: Volunteer to Track Bird-Window Collisions at Residences

Even with most volunteer programs on hold for public health reasons, there’s still a way to participate in bird-window collision monitoring from home.

The normal format of the Avian Collision Team (ACT) will not be possible this spring. Last year, ACT involved around 40 volunteers looked for dead or injured migrants along routes through Boston. Working a couple of days each week during migration, those volunteers tallied 193 window-struck birds in total, representing nearly five dozen species.

Many volunteers, once primed to look for window strikes, also started reporting injured birds outside their homes and offices. Window strikes are indeed not only an urban issue, and houses in the suburbs or countryside play an important role. While a skyscraper kills an average of 24 birds per year, low-rises are not far behind at 22, and most single-family residences kill between 1–3. (Buildings vary, of course, and some are responsible for more than 100 collisions a year).

Feathers left behind on a glass residential window after a bird collided with it.

Residences: a silent culprit

Standalone homes are responsible for 90% of bird-window collisions. Even though sleek, all-glass facades on non-residential buildings kill many more birds on a per-building basis than the average single-family home, residences are more than 60 times as common as tall city buildings—making their collective impact even more significant.

More importantly, bird collisions are harder to detect outside of the city. Landscaping around houses conceals the bodies of window strike victims, and scavengers like raccoons and squirrels abound. Consequently, window strikes at residences are underreported.

Help us track bird-window collisions at home

Participating in this project requires less effort than a normal ACT season, since it only involves a quick daily check at one building (your home). It’s important, however, to make this a daily or near-daily routine, since there may only be one or two days out of the season when you find a bird (although there may be many more). As always, data on where window collisions are not occurring is just as important as where they are. The data from this project will help us better understand the problem and eventually develop recommendations for reducing bird kills caused by window collisions at residential structures and low-rise office buildings.

The survey period officially runs until June 2, when most migrants are settled into their breeding territory. Anyone is welcome to continue submitting data after that, though—breeding birds are nearly as likely to collide with windows as migrants.

If you want to learn how to make your home safer for birds, check out these tips. Please only put up bird-friendly products like window tapes or screens before or after the data collection period. Modifying your windows in the middle of the data collection period will make it impossible to analyze data from your building.

To learn more about why birds have a hard time detecting glass, and to sign up to survey your home, visit our Anecdata webpage.

Two New Citizen Science Projects for 2020: Kestrel and Swallow Nest Site Reporting

American Kestrels, Barn Swallows, and Cliff Swallows are all declining in Massachusetts, like many other open-country birds. The Bird Conservation team is initiating two exciting studies on these species during this spring and summer, and data from the community will be integral to both studies’ success!

Barn Swallow young on nest (Photo by Ginger Lane)

Have you seen these birds nesting?

If you have any information on these species’ current (2020) nest sites, or are willing to look for them, please submit data via our swallow project and kestrel project webpages on Anecdata (a citizen science website).

You’ll need to set up an Anecdata account first. Click on “register” to first create an account, and click on “join project” once you’ve signed up with Anecdata.

A screenshot of a social media post

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Both projects are fairly simple for users: simply click on “add an observation” and report the coordinates of nesting American Kestrels, Barn Swallows, and Cliff Swallows.  In the case of both swallow species’, it’s also useful to know if you observe structures that do NOT host a colony but which you think potentially could (e.g., old barns or small wooden bridges near open grassland and freshwater). Note that this study is focused on nesting sites, not places where birds are observed foraging or flying around.

What we hope to accomplish with your help

The purpose of the swallow project is straightforward: we want to identify sites where Barn and Cliff Swallows are nesting that may not yet be known to biologists.

Mass Audubon’s work on the kestrel project on the other hand, will be a little more involved. After compiling a list of remaining nest sites, the Bird Conservation Department will team up with state biologists in 2021 to fit kestrels with radio tags. These tags will track their movements around the region after nesting, and eventually to their wintering grounds.

Kestrels breed widely throughout Massachusetts, but there are many Breeding Bird Atlas blocks that showed declines between Atlas 1 (1974-1979) and Atlas 2 (2007-2011). Interestingly, there are both urban-nesting and farmland-nesting American Kestrels, and the two populations may be showing different population trajectories. Studying the life histories of these birds, including tracking their movements away from nest sites, could hold clues as to why so much apparently good kestrel habitat goes unoccupied in the state.

As always, all nest data is kept strictly within the community of biologists working to conserve these species.

American Kestrel at nest box (Photo by Mark Grimason)

More Tips For Searching

  • Both projects run from May 20 – August 20, to reduce potential confusion between nesting birds and migrants.
  • The focus is on nest sites and not on places where birds are seen flying around.
  • If you need a refresher on identifying Barn and Cliff Swallows in the field, check out our ID tips for these similar-looking birds.
  • Please participate only if you can do so in your own local communities.
  • It’s likely that some sites will be on private property where direct observer access is impossible. Please don’t trespass! Even if you’re only able to observe from a road edge and can’t collect, it’s helpful to know that you saw swallows or kestrels entering or leaving a particular cavity or structure.

All three of these species were once common sightings in rural parts of Massachusetts, and they’re all a joy to observe and spend time near. Thank you for helping Mass Audubon protect them, and happy birding!

The Saga of the “Robin Snipe”—An Artful Overview of an Atlantic Flyway Tragedy

The Red Knot (Calidris canutus) is a shorebird, roughly the size of an American Robin, and similarly colored in spring, with rusty red underparts and a ruddy brownish back sprinkled with black and calico. This species’ legacy has been punctuated by eras of superabundance, intense market hunting persecution, habitat disruption, and most recently anthropogenic events that have nearly brought the Atlantic flyway population to its knees. Favored sandy beaches on the South Shore of Cape Cod Bay and outer Cape Cod in Massachusetts have for many decades hosted great numbers of “Robin Snipes” (so-called by early market gunners) during their autumn migration en route to the far reaches of southern South America for the winter. And it was on these same Bay State beaches that the Atlantic population of knots was mercilessly persecuted from July-October during much of the 19th and early 20th century. 

Red Knot (Photo by A Grigorenko)

Fast forward to the last half of the 20th century when the ornithological community, initially in the Mid-Atlantic Coast region, began systematically registering measurable declines in the vast numbers of knots that once stopped on Massachusetts shores during autumn migration and on the shores of Delaware Bay in May. These early warnings presaged what was to become one of the most precipitous declines in modern shorebird history. The sad and well-documented chronicle of the near collapse of the eastern North American Red Knot population is one of the most dramatic sagas in modern-day bird conservation.

The pathos and intimate details of this ongoing conservation drama have recently been eloquently presented in Orion magazine by author and Audubon A awardee Deborah Cramer and artist Janet Essley. To explore the details of this fascinating story, follow this link >

Enjoying Nature From the Comfort of your Phone

While many of us are stuck at home, opportunities to explore nature are more limited.  However, there are many ways to engage with nature from your phone or computer, from sharpening your ID skills to submitting observations to a citizen science project. Below are five apps that will keep naturalists and non-naturalists engaged and excited.  

iNaturalist 

This app is like social media for nature sightings. The platform is designed to connect people to a community of wildlife and plant enthusiasts. Create a (free) account and upload photo (or audio) observations of living things. iNaturalist will give you its best guess based on your location and identifications of similar-looking species. Other users can comment on your observations and suggest an ID, which helps the program better identify future observations. Plus, iNaturalist observations can be scientifically useful: iNaturalist’s database has been used to redraw species range maps, and even describe new species.

Seek 

If you want to use iNaturalist’s identify tool without the rest of the app’s features, consider downloading Seek instead. This app has been described as “Shazam for nature” for its ability to ID a living thing by just pointing your camera.  

eBird  

This app is for bird-lovers and life-listers. Create “checklists” of any birds you see in a fixed location or on a walk. eBird tracks your distance and time and shows you a list of possible species based on your location. A half-moon orange circle notes uncommon species for the area and a red circle notes rare species.  

As with iNaturalist, eBird sightings become part of a database of millions of observations, helping scientists monitor large-scale patterns in bird populations.

Merlin Bird ID 

If you’re new to birding, consider downloading Merlin from the Cornell Lab of Ornithology. Browse a digital field guide of photos, bird sounds, and maps or answer five questions based on a bird you saw to have the app give you its best guess. 

Zooniverse 

Think of this app as digital volunteering. Instead of going out and monitoring nests, you can digitize historical nesting info (see below) that researchers at Cornell Lab of Ornithology will use for their database. Of course, this is only one of any citizen science projects on Zooniverse and topics range from nature to history and everything in between. The app will even track your progress, allowing you to see how much you’ve accomplished. 

Let us know if you decide to use any of these, have used them before, or have other recommendations for nature-based websites and apps you love! 

Looking for Love in All the Wrong Places: The Woodcocks of Alewife Reservation

American Woodcocks appear to be thriving at the Alewife Reservation in Cambridge, an urban wild sandwiched between office complexes and a subway garage. Despite the myriad dangers of city life, up to a dozen woodcocks perform their aerial mating displays over Alewife every March.

Resilience against the odds

Alewife is awash in threats to these hapless birds. Peregrine Falcons occasionally snag woodcocks in midair as they hunt along the clifflike walls of a brutalist-era parking garage. The expansive glass façade of the recently-expanded office park looms over the adjacent greenspace, causing fatal window collisions. Feral cats prowl around the urban wetland’s thickets. Heavy metals and pollutants from long ago still linger in the soil.

At Alewife, small patches of woodlands, wetlands, and fields persist amid urban infrastructure and new development.

And yet, at least a handful of woodcocks return here every year. In early spring, they give their explosive, nasal calls at dusk, leap into the sky, and twist and turn in midair to attract a mate. Once paired off, they nest and raise young in nearby woodlands.

Is it a trap?

It’s worth considering that this urban wild might be what’s known as an “population sink,” or “ecological trap.”

An ecological trap is any low-quality habitat where more birds die than can successfully reproduce, but which attracts birds even when there’s safer places for them nearby. Traps can appear to have a stable population of birds, when in fact most of those birds die before being replaced as more birds are lured in from safe areas.

A population sink, on the other hand, doesn’t necessarily attract birds more than areas with suitable habitat. Rather, birds end up there as “overflow,” when better territories are fully occupied or made inaccessible. Sinks don’t cause as steep declines, but do put a cap on the birds that can successfully reproduce in an area.

So, it’s entirely possible that Alewife isn’t doing the woodcock population any favors. No woodcock nests have been found in the area, but that doesn’t necessarily mean they’re failing to reproduce.

Brushy fields are all you need

Whether or not Alewife is a net plus or minus for its resident woodcocks, data from the rest of the country show that habitat availability is the main factor limiting woodcock abundance.

The strange, lumpy, long-billed form of an American Woodcock (Scolopax minor). Photo: Will Freedberg

Woodcocks love fields with low, woody brush, and adjacent mature forest. They display in springtime over open, grassy areas, but need some cover—ideally patches of shrubs or grass 2’-5’ high—for shelter. They use forest to forage during the rest of the year, especially when they’re raising young.

Without disturbance, either by fire, mowing, or agriculture, brushy fields revert to forest in a couple of decades. This is the story of woodcock habitat across Massachusetts: most ex-farmland has reverted to forest. Remaining fields are farmed more intensively, leaving less and less brushy patches and edge habitat, and fallow fields are becoming rarer.

Mass Audubon’s Foresters for the Birds program is emphasizing the value of young forest and shrubland habitat for birds. By educating foresters and landowners on bird-friendly forestry practices, we’re trying to create more habitat for woodcocks and other young forest specialists.

Great Shearwater © Peter Flood

Keynote at This Sunday’s Birders Meeting: Peter Marra

Birders Meeting Logo

Do you remember the paper on bird declines that made global headlines last fall? Its lead author, Pete Marra, will be speaking on the science behind bird migration at this Sunday’s Birder’s Meeting.

Marra’s studies have helped guide bird conservation priorities for the past 20 years, in part through his work at the Smithsonian Institution and Georgetown University.

This Sunday, we’ll get to hear him discuss new discoveries on how, why, and where birds make long-distance journeys—and why it may not be too late to save some of North America’s most imperiled migrants.

Great Shearwater © Peter Flood

Other speakers will follow the theme of bird migration:

  • Mariamar Gutierrez will take us through the ways in which new technologies can help us track and understand migrant birds’ movements.
  • Sean Williams, ornithology professor and one of Massachusetts’ top birders, will discuss the best hotspots for seeing big numbers of Spring migrants.
  • Speakers on Chimney Swifts (Margaret Rubgea– UConn), shearwaters (Kevin Powers–FWS), window strikes (Will Freedberg– Mass Audubon) and more!

Of course, there will be a number of other draws in addition to speakers. We’ll have a vendors area staffed by nature tour agencies, booksellers, and local bird-related companies. A number of raffle items will include field guides, bird feeders, and other birding goodies. Most importantly, there’s the chance to meet new community members, catch up with old friends, and stay up to date on news in the Massachusetts birding world.

Attend the Event

Whether you come out to learn, socialize, or both, we hope you’ll join us this year!

The 2020 Birders Meeting will take place on Sunday, March 8 from 8 am-4:30 pm, at College of the Holy Cross in Worcester.

Get your ticket >

Be on the Beaver Lookout

Mass Audubon and the Boston NASA DEVELOP National Program team are collaborating to learn more about how Massachusetts beavers impact the landscape using satellite imagery, and we need your help.

The NASA DEVELOP National Program addresses environmental and public policy issues through interdisciplinary research projects, applying NASA Earth observations to community concerns around the globe. Teams of DEVELOP participants partner with decision-makers to conduct 10-week rapid feasibility projects, highlighting relevant applications of NASA Earth observing missions, cultivating advanced skills, and increasing understanding and use of NASA Earth science data and technology. The DEVELOP Program conducts 55-65 projects annually across 11 national locations. This spring, the DEVELOP Boston team is partnering with Mass Audubon to explore how beavers influence the Massachusetts landscape.

Beaver © Allison Bell

A Conservation Success Story 

The beaver (Castor canadensis) is North America’s largest native rodent. They are adapted for aquatic environments and easily recognizable by their long, flat tail and sharp front teeth.

European colonists found beaver’s thick, waterproof fur highly desirable and decimated their populations across the U.S. Unregulated trapping, deforestation, and the destruction of wetlands led to the local extinction of beavers in Massachusetts by the end of the 18th century.

In one of the most successful conservation efforts in U.S. history, New York reintroduced approximately 20 beavers from Canada and Yellowstone in 1904. By 1915, the population exploded to about 15,000 individuals and began to disperse to surrounding states. In 1928, beavers were discovered in West Stockbridge, the first recorded occurrence in Massachusetts since 1750.

To support Massachusetts populations, Mass Audubon’s Pleasant Valley Wildlife Sanctuary reintroduced three additional beavers in 1932. Today, beavers have been restored to nearly their entire historic range throughout the state, found everywhere except Cape Cod.

Busy Beavers Build Habitat

Beavers are known as ecological engineers. They alter and create new habitats by building dams from sticks and mud to create still, deep ponds. These ponds provide beavers with access to food, protection from land predators, and shelter.

Beaver Pond © Allison Bell

By building dams and creating ponds, beavers restore lost wetlands, of which about half have disappeared in the lower 48 states since European settlement. Beaver ponds are home to rich biodiversity, including amphibians, reptiles, spawning fish, muskrats, bats, various birds, and a wide variety of plants.

Altering the hydrology helps control downstream flooding, improve water quality, trap silt, and resupply groundwater. When the dam is abandoned and the pond drains, nutrient-rich silt creates highly productive meadows. However, beaver dams may cause unwanted flooding to neighboring properties, but can be mitigated through various solutions.

Tracking Beavers from Space and on the Ground

The spring 2020 Boston NASA DEVELOP team is using NASA satellite imagery to find and track beaver flooding events across Massachusetts to see how their populations are impacting landscapes. The team will be corroborating potential beaver flooding using iNaturalist beaver observations. iNaturalist is an online citizen science platform, where users upload and identify species observations (images or audio recordings).

Map showing beaver flood events at Wachusett Meadow & Broadmoor Wildlife Sanctuaries © Dr. Valerie Pasquarella, Boston University

How You Can Help

Help Mass Audubon and the NASA DEVELOP team by reporting beaver signs, including dams, lodges, chewed logs, or beaver themselves using iNaturalist, either in our sanctuaries or anywhere across Massachusetts.

https://static.inaturalist.org/photos/60714452/large.jpeg?1580660129
Beaver chewed tree at Ipswich River Wildlife Sanctuary reported on iNaturalist © Jennifer Clifford

Written by Cameron Piper, TerraCorps Service Member