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

Mass Audubon works on “Climate-Smart Forestry”

The Massachusetts Department of Conservation and Recreation has funded Mass Audubon for three years of “Climate-Smart Forestry.” This program is a collaborative effort between Mass Audubon and the New England Forestry Foundation (NEFF) to support landowners in making climate-friendly forestry management decisions. This is especially important in Massachusetts, where forests cover 60% of the total land area and much of it is privately owned. 

The Climate-Smart Forestry project is divided into three main “tasks.” The first is to update the state’s Forest Stewardship Plan to include a climate component. This is a voluntary program where landowners work with consulting foresters to create a ten-year management plan. Future plans will explain how a landowner’s forest fits into the larger climate change picture, and will nicely complement our Foresters for the Bird Program.

Mass Audubon Central/Western Regional Scientist Tom Lautzenheiser educates a group of forestry professionals about sustainable forest management at Mass Audubon’s Elm Hill Sanctuary.

The second task is encouraging municipalities to participate in carbon offset markets. Forest landowners receive payments from the California Compliance Offset Program for carbon stored in the trees on their land. In exchange, these landowners reduce clear-cutting and lengthen their harvest rotations to maintain a specified level of carbon storage over time spans ranging from 40 – 100 years.  

The third task is to update the Best Management Practices (BMPs) for timber harvesting to address the reality of climate-driven changes in harvesting conditions and promote climate-friendly practices. This will be completed by NEFF, which currently provides BMPs designed to reduce erosion and minimize damage to wetlands and soils during harvest operations. The updates will ensure that projected changes due to climate change are reflected in BMPs. 

The project is led by Jeff Ritterson and Josh Rapp in Conservation Science. Jeff currently leads our Foresters for the Birds program and is developing a project for Bird Friendly Maple Syrup. Josh has 15 years of experience in forest ecology research with an emphasis on climate change impacts on forests. Tom Lautzenheiser, who led the effort to enroll Mass Audubon lands in the California carbon market, will contribute heavily to the carbon offset component. Alexandra Vecchio, Climate Change Program Director, will contribute her experience in building climate resilience at the municipal scale, as well as expertise in climate change communications and education for the various outreach components of this project. 

ACT Season 2 Wrap-up

The Avian Collision Team is a volunteer effort to monitor bird-window strikes in downtown Boston. This fall was the second season, running from early August to mid-October. Volunteers walked 7 survey routes from Saturday to Tuesday between 6 and 9 a.m., finding a total of 74 individuals. This makes 193 total strikes between the fall and spring seasons. 

The volunteer process

Birds that were alive but injured, which was about a quarter of the time, were taken to Tufts Cummings School of Veterinary Medicine to be rehabilitated and released. Those that were deceased were collected and donated to the Harvard Museum of Comparative Zoology’s Ornithology department to be used as study specimen. 

Note: Mass Audubon’s volunteers collect specimen with a permit from the Division of Fisheries and Wildlife. It is illegal to collect birds under the Migratory Bird Treaty Act.

A Commmon Yellowthroat outside of University Hall at UMass Boston

Table 1 shows a preliminary roundup of the window-strike species found by ACT volunteers. Locations and images can be found on iNaturalist, where other citizen scientists around the world are submitting similar window-strike data on a project called “Bird-window collisions”.  

Table 1: Number of individuals of each species found by ACT

White-throated Sparrow. . . 23 House Finch. . . . . . . . . . . . . . . . 3 Black-billed Cuckoo. . . . . . . . . 1
Ovenbird . . . . . . . . . . . . . . . 22 Northern Waterthrush. . . . . . . 3 Yellow-billed Cuckoo . . . . . . . 1
Common Yellowthroat . . . . 19 Blackpoll Warbler. . . . . . . . . . . 3 Red-eyed Vireo. . . . . . . . . . . . 1
Hermit Thrush . . . . . . . . . . . 7 Northern Flicker . . . . . . . . . . . . 2 Blue-headed Vireo . . . . . . . . . 1
Black-and-white Warbler. . 7 American Robin. . . . . . . . . . . . . 2 Blue Jay . . . . . . . . . . . . . . . . . . 1
Lincoln’s Sparrow . . . . . . . . 6 Song Sparrow. . . . . . . . . . . . . . 2 European Starling . . . . . . . . . . 1
Magnolia Warbler. . . . . . . . 5 Nashville Warbler. . . . . . . . . . . 2 Cedar Waxwing . . . . . . . . . . . 1
American Redstart . . . . . . . 5 Chestnut-sided Warbler. . . . . . 2 Veery . . . . . . . . . . . . . . . . . . . . 1
Brown Creeper . . . . . . . . . . 4 Black-throated Green Warbler 2 Chipping Sparrow. . . . . . . . . . 1
Golden-crowned Kinglet . . 4 Canada Warbler. . . . . . . . . . . . 2 Clay-colored Sparrow. . . . . .  . 1
Dark-eyed Junco . . . . . . . . . 4 Indigo Bunting. . . . . . . . . . . . . . 2 Swamp Sparrow . . . . . . . . . . . 1
Savannah Sparrow. . . . . . . 4 Virginia Rail. . . . . . . . . . . . . . . . 1 Pine Warbler. . . . . . . . . . . . . . 1
Northern Parula . . . . . . . . . 4 Belted Kingfisher. . . . . . . . . . . 1 Black-throated Blue Warbler 1
American Woodcock . . . . . 3 Yellow-bellied Sapsucker. . . . . 1 Palm Warbler. . . . . . . . . . .  . 1
Ruby-throated Hummingbird 3 Red-bellied Woodpecker . . . . 1 House Sparrow. . . . . . . . . . . 1
Mourning Dove . . . . . . . . . . . 3 Red-breasted Nuthatch. . . . . . 1 Brown-headed Cowbird . . . 1
Swainson’s Thrush . . . . . . . . . 3 White-breasted Nuthatch. . . . 1 Baltimore Oriole . . . . . . . . . 1

Note: This list is still being updated as we finalize our data

As evident in Table 1, window collisions in downtown Boston during the times in which we survey are primarily migratory species. Much like moths to a light bulb, migrating birds are drawn to city lights during their nighttime migratory journeys. They land in cities and in the early mornings when they re-orient themselves and look for food, they fly into glass windows. Learn more about this hazard and how you can do something about it on Mass Audubon’s website

A Lincoln’s Sparrow at the John Hancock Tower

ACT will start again during spring migration, running its third season from April 11 – June 2. Sign up to be a volunteer and direct questions to kkeohane@massaudubon.org. 

Drumlin Farm is banding Massachusetts’ smallest owl – the Northern Saw-whet

A team of researchers measure the wing feathers on a Saw-whet owl at Drumlin Farm’s banding center. Handling owls is only legal with a government permit, and only by researchers trained to handle them safely.

Each year, Mass Audubon sanctuaries across the state set up banding stations to track Saw-whet owl migration. Drumlin Farm in Lincoln, Moose Hill in Sharon, and Daniel Webster in Marshfield all have dedicated crews of Saw-whet owl banders. November is the best time to find these tiny predators, as large numbers are passing through Massachusetts on their migration route.  

Saw-whets were an under-studied species 

At 7-8 inches long and weighing 2-5 ounces, Saw-whet owls are about the size of an American Robin. Because of their small size, Saw-whets are difficult to find. Many birders used to consider them a rarity, but in 1994 a study at Daniel Webster Wildlife Sanctuary revealed that these birds are much more widespread than previously thought. In fact, they are found in higher numbers than any other owl species in Massachusetts in the fall. 

Saw-whets are migratory 

Not only were these birds mistakenly thought to be a rarity, but they were also thought to be permanent residents. With anecdotal evidence as well as increased banding efforts, researchers have discovered that most of them do migrate, and can travel as far south as the Mexican border. Their migration routes, however, are less consistent and more unpredictable than other migrants, making them a complicated species to study.

A scientist holds a Saw-whet Owl with a “bander’s grip,” securing it’s talons in a way that’s safe and comfortable for both the bird and the human.

Banding efforts in the US 

In 1994, Project Owlnet was initiated as a way to bring together data from across the country and recruit new banding stations. Participating organizations share research and best practices to better understand these birds. The map below shows a map of owl banding stations that are a part of Project Owlnet. 

Mass Audubon sanctuaries contribute to this dataset by banding, weighing, and measuring Saw-whets. They also identify each bird’s age, sex, and take feather samples for DNA research. 

Fun fact: Saw-whet age can be determined with UV light 

The fluorescent color in young owl feathers comes from a pigment called “porphyrin,” which causes the feathers to appear red under UV lights. This pigment breaks down over time and exposure to light, so researchers can use this technique to identify an owl’s age. The pictures above show a second-year Saw-whet because they have clear pink hues in their newer primary feathers and on their coverts.  

Findings 

The map below shows banding stations in Massachusetts (yellow dots), Saw-whet owls from Massachusetts that were recaptured elsewhere (red dots), and Saw-whet owls banded elsewhere that were recaptured in Massachusetts (blue dots). Owls have been banded along their migratory route from as far north as Ontario and as far south as Maryland. 

Interested in seeing these owls for yourself? Join Mass Audubon at one of many upcoming nocturnal events. Happy owling! 

Report on Barn Swallows in Hadley Now Available

The final report describing “Barn Swallow Nesting Biology at Bri Mar Stable, Hadley, Massachusetts During 2019” is available here. The report, written by Mass Audubon’s Director of Bird Conservation, Jon Atwood, as well as collaborators with the U.S. Fish and Wildlife Service, describes the scientific context and behavioral ecology of Barn Swallows nesting at the Fort River Division of the Silvio O. Conte National Fish and Wildlife Refuge.

In Mass Audubon’s formal response to the proposed demolition of an abandoned horse stable that is used by a large colony of nesting Barn Swallows, we wrote “If the barn does indeed need to be demolished in the near future, Mass Audubon supports the Refuge’s proposed action, Alternative A – Phased Closure of Stable and Delayed Demolition. We encourage the U.S. Fish and Wildlife Service to use the opportunities available under Alternative A to study methods that can be used to promote colony relocation on private and public lands. We also support monitoring of Barn Swallows on and around the site during the phased closure process. Mass Audubon’s bird conservation staff are willing to advise and support the refuge staff in those efforts.”  This report is the result of this promised research effort.

The report provides useful data that is relevant to decisions regarding future plans of the refuge. There is no doubt that this site hosts a large colony of this declining species. However, multiple authors have pointed out that factors other than availability of nest sites are most likely responsible for the species’ regional population declines, and have even noted that small colonies often have higher reproductive success than large nesting groups. In 2019 we had good success in attracting swallows to nest in an adjacent structure where they can be protected in the future. And, we also discovered other nearby Barn Swallow colonies, including at least one site that is probably comparable in size to the colony at Bri Mar Stable.

We’ll keep you posted as we learn more about this ongoing issue.

Barn Swallows nested on electrical boxes in structures nearby the Bri Mar Stable. Photo by Ainsley Brosnan-Smith.

Errata: After we published the final report about Barn Swallow nesting biology at Bri Mar Stable, we discovered information about past nesting activity within the Boat House. These sentences, found in the Abstract and Results sections of the report, have been corrected.

Dial-a-Bird: A Tribute to the Voice of Audubon

Before the internet age, informational phone lines were widespread— providing everything from weather forecasts, time of day, or even local rare bird alerts.

Mass Audubon started the original bird hotline in 1954 with some help from a telecom executive, Henry Parker, who happened to be an avid birder.

In fact, the system that Parker developed for the Voice of Audubon came before the widespread use of phone hotlines. The Dictaphone-based system he gave Mass Audubon eventually became the basis for other users to pre-record airline schedules, theater showtimes, and other, more general-interest uses.

The rarities hotline, called “The Voice of Audubon” or VoA, reduced the need for staff to recite sightings to every birder who asked—making it as much a boon for Mass Audubon as for the hundreds of birders calling in each week.

Making the Papers

Shortly after its introduction, the Voice of Audubon was incorporated every week into a bird sightings column in the Boston Globe.

Initially, non-birder Globe interns had to transcribe the bulletin entirely by ear, leading to some amusing misspellings of bird names—such as “wobbling vireos” instead of “Warbling Vireos, “dowagers” instead of dowitchers,” “dick sizzles” instead of “Dickcissels,” and a “pair of green falcons” instead of a “Peregrine Falcon.” Eventually, a written transcript was made available to anyone interested in printing the week’s bird sightings.

A group of photographers respond to a report of a rarity, in this case a Great Gray Owl in southern New Hampshire. Always be respectful of vagrant birds– particularly owls and waterbirds– by not approaching them.

Changing Tastes

The Voice of Audubon became a wildly popular model, with similar call-in lines eventually cropping up in most US states. The nationwide rare bird alert even made it in the birding-centric Hollywood movie, The Big Year.

Email changed everything for birding hotlines. With the advent of the listserv, or email message board, call-ins to the Voice of Audubon began to decrease.

Listservs went out of vogue when eBird emerged on the scene, revolutionizing how birders reported their observations. Still, some preferred listservs for the opportunity to discuss sightings in addition to reporting them, for the way listserv conversations build community, and for the ease of reporting a sighting in text rather than via online form. These needs have also come to be addressed by Facebook groups for bird sightings, adding another medium vying for birders’ time and information.

Standing the Test of Time

Through it all, the Voice of Audubon has held firm as a resource for birders, even as it’s call-ins have declined since the heyday of the 1960s and 70s.

Continuing to publish the VoA serves a dual purpose. Firstly, it informs birders who don’t have access to a computer or who prefer the hotline format. Perhaps more importantly, its existence and regular publication in newspapers serves to raise the public profile of birdwatching among the general public.

Do you ever call the Voice of Audubon (781-259-8805), read it in the Sunday Globe, or check out the sightings on our website? Let us know in the comments!

Do Vagrant Birds Indicate a Changing Climate?

It’s been an incredible past few weeks for rare birds in Massachusetts. First, a Purple Gallinule showed up in Milton. Then a White-faced Ibis arrived in Sterling, and a Tropical Kingbird shocked birders in Belmont—the first ever to be seen in Middlesex County. Finally, the first Pacific-Slope Flycatcher seen anywhere in the state was spotted in Hadley, and a Western Kingbird and Rufous Hummingbird rounded out the glut of unusual visitors.

More than 2,000 miles from home, this boldly-colored Tropical Kingbird in Belmont made birding headlines.

It’s tempting to think that these out-of-range birds (or “vagrants”) are the result of climate change. Although climate change certainly affects species’ normal ranges, and may make vagrancy more common and extreme, it’s a reach to say that these “lost” birds themselves indicate any larger trends.

Instead, these birds are just as likely examples of species that only show in Massachusetts every several hundred years. This phenomenon of once-in-a-lifetime birds has plenty of precedent. Consider, for example, the first time a Masked Duck was seen in Massachusetts was in 1889—and the species hasn’t been reported in New England since. Similarly, the first and only record of a Brewer’s Sparrow was in 1873, and the first and only record of a White-tailed Kite was in 1910.

Vagrants: Unpredictable in Predictable Ways

As fall migration draws to a close, there’s almost always a spike in vagrant birds in Massachusetts. Birds from the interior southwest of the US ride winds blowing northeast, often making it as far as the coast.

Many bird populations contain a few individuals prone to wandering. In some cases, wanderers are biologically hard-wired to migrate differently than others of their species, and in other cases, the cause is unknown. These outliers aren’t unique to migratory species; even flightless penguins have been documented walking into the icy mountains of Antarctica, far from any food source.

Most vagrants either perish or (less often) make it back to their home ranges. Even if the vast majority of these birds don’t manage to reproduce on terra incognita, some scientists theorize that having a few exploratory or mis-oriented individuals gives the species an evolutionary advantage. This may allow a population to very occasionally colonize new, faraway areas that turn out to be hospitable, serving as a bulwark against sudden cataclysmic change across its entire normal range.

Climate Affects Vagrants, But Vagrants Aren’t Necessarily Climate Indicators

Fall isn’t the only time when wind patterns regularly bring Massachusetts a handful of unusual birds. Southern birds that overshoot their breeding grounds in spring are mostly the result of wind patterns that blow them far over the Atlantic, where they continue north until making landfall in New England. Even more noticeable are the hurricanes that have brought tropical seabirds like Sooty Terns and Red-billed Tropicbirds inland into Massachusetts.

As rising global temperatures create stronger storms and shift continental wind currents, it’s reasonable to think that new patterns in bird vagrancy will emerge. This doesn’t mean, however, that recent “firsts” (such as last month’s Pacific-slope Flycatcher or Tropical Kingbird) are indicators of climate change– especially with only 200 years of records and a long list of vagrants that showed up in the 18th century and never again.

Demonstrating an increase in vagrant birds (or changes in where they show up) is a tricky proposition, in part because there’s no good way to adjust for how many people are looking. Not only has the number of birders increased dramatically since the 19th century, but birders’ knowledge of how to predict vagrants has improved—and their interest in finding them has intensified. This complicates studying patterns in bird vagrancy, let alone linking them to long-term climate trends.