The Death of a Warbler: A Tragedy in Four Chestnut-sided Parts

Prologue

In addition to collecting data on bird-window collisions, Mass Audubon’s Avian Collision Team also generates many good stories that range from hopeful, to tragic, to simply strange. While most of the birds our volunteers found were dead, some were nursed back to health at the Tufts Wildlife Clinic. What follows is an account of one window-struck Chestnut-sided Warbler (Setophaga pensylvanica) that proved to be an emotional roller coaster for our project coordinators.

Part I: The warbler is alive

A dedicated ACT volunteer called up about a handful of window-struck birds outside a building facing the Boston Public Garden. Most were dead, but for a single Chestnut-sided Warbler. It was apparently sitting on the curb, visibly breathing, but injured. The volunteer was a little shaken up. Since they didn’t have a net or tools to safely catch the bird, I advised them to wait to see if the bird could fly off on its own before trying to catch it.

Our volunteers snapped a quick cell phone photo of the injured warbler next to the curb.
Our volunteers snapped a quick cell phone photo of the injured warbler next to the curb.

Part II: The warbler is dead

A few minutes later, the volunteer called back– sounding even more shaken. The bird had flown away, but just as it lifted off, it was caught in a gust of wind from a passing car and was struck by the fender. From the volunteer’s description, the bird was truly lifeless. The volunteer said they would take the carcass back to their freezer and eventually bring it to the Harvard zoology museum, where we had been depositing specimens for research.

Part III: The warbler is alive, again

“It’s alive!” were the first words out of the volunteer’s mouth on our third phone call within a half-hour. “The bag started moving!”

Stunned birds can truly appear lifeless, and in fact, many birds that hit windows are stunned, concussed, or go into shock before eventually shaking themselves off and flying away. But just because a bird can fly doesn’t mean it’s healthy. A broken clavicle or corocoid bone allows birds to make short flights, but prevents them from gaining altitude, halting their migration and making them an easy meal for predators. Any bird found stunned from a building impact is a good candidate for treatment at a wildlife care center.

The volunteer met Mass Audubon staff at a nearby T station to hand off the bird, which was taken to Tufts Wildlife Clinic.

Part IV: The warbler is dead. Again.

The Tufts clinic graciously provides every animal with a case number, so its finder can call up to check on its condition.

While the bird was initially given an optimistic prognosis, we learned a few days after dropping it off that it had suffered untreatable head trauma. The bird had died.

Epilogue

While healthy bird populations naturally fluctuate enough to practically erase the effect of one birds’ death, there is no harm in trying to save individual lives. Naturally, most volunteers prefer to put in the extra effort involved in helping injured birds than leave them to die from an indirectly human-inflicted injury. It was sad not to be able to save this warbler, but we did successfully release a number of other birds, including Brown Creepers, Song Sparrows, Ovenbirds and Common Yellowthroats.

If you want to help monitor window collisions and ambulate injured birds, join Mass Audubon’s Avian Collision Team for its fall migration via this form!

Join the Avian Collision Team’s Second Season

Here’s an easy way for anyone living or working in Boston to help migratory birds: help monitor window collisions!

An Indigo Bunting lies stiffly among litter, hours after striking an office building window in Boston. (Photo: ACT)

Mass Audubon is seeking new volunteers for the fall season of the Avian Collision Team (ACT). ACT is an initiative to collect data on bird–building collisions, and to rescue injured birds.

This spring, the team of birders, conservationists, and other concerned citizens observed 115 birds across 38 species affected by window strikes. This fall, and in coming seasons, we need to keep up the momentum and grow our dataset.

The Problem

Window collisions are an under–appreciated source of bird mortality in the US, causing several hundred million casualties annually.

Birds struggle to distinguish reflections from reality, and often strike glass windows that reflect the sky or nearby greenery. City lights also confuse night-migrating birds, which use the stars to navigate, and which often land near sources of light pollution. Many window strikes occur as birds try to re-orient in the morning, after being drawn in to an unfamiliar concrete jungle.

Project Details

The program runs from August 24–October 28 in downtown Boston. Volunteers need to sign up for 1-4 weekly shifts, Saturday–Tuesday, that can take place between 6-9am. Most shifts last around 30-60 minutes.

Volunteers walk predetermined routes through downtown Boston to photograph or collect deceased specimens, fill out data sheets, and occasionally rescue live birds. We’ll be holding volunteer trainings on August 11, 18, and 22.

Carrying out ACT surveys can be an eye-opening experience, between watching the city as it’s waking up, discovering seemingly out-of-place warblers, buntings, and vireos, and occasionally saving the life of an errant, injured migrant. And once you’ve found your first few birds, a collector’s instinct sometimes kicks in, making the search all the more engaging. It’s like birding with a twist– a sense of urgency, purpose, and sometimes, a touch of sadness.

If this sounds compelling, sign up here!

Avian Collision Team: First Season Updates

Since mid-April, a team of Mass Audubon volunteers has combed the streets of downtown Boston in search of migratory birds killed by collisions with windows. Here are some preliminary results of our first season running the Avian Collision Team (ACT).

The first statistic that jumps out is the higher-than-expected number of live, injured birds found by our volunteers. Based on what we heard from New York, Chicago, and Toronto, we had told volunteers it was highly unlikely they’d be able to save any injured birds. This ended up being far from the truth! Here’s one video of a Brown Creeper that was well enough to be released after suffering non-life-threatening head trauma:

The Five “Hardest-hit” Species

Some patterns are also beginning to emerge in the species of birds we’ve been finding. Here’s the full breakdown:

The five most frequently-encountered birds (in bold text above) have something in common: they’re all low-flying migratory species, and they’re relatively common. Certain buildings also seemed to kill a disproportionate number of birds that climb trees vertically, like woodpeckers, nuthatches, Black-and-white Warblers, and Brown Creepers. Other cities have reported similar species profiles with an emphasis on common migratory birds that fly low and weakly.

The Bottom Line

A few dozen people surveying a thin slice of the city for an hour or so per week found 119 window-struck birds of 38 species.

Other cities report that certain seasons have up to four times the number of strikes than others. The wide variability of window strikes makes it difficult, after just one season, to make broad statements about how many birds die from collisions in Boston annually, or establish how Boston shapes up compared to other cities. That said, our numbers fall roughly into the range reported by similarly-sized programs in other cities, like Baltimore, Detroit, and New York.

After accounting for scavengers, industrious building cleaners, and low volunteer detection rates, it’s estimated that only 10-20% of window strikes on a given route are actually recorded. That makes our numbers all the more sobering, especially considering our volunteers covered less than 1/50th of the street area of Boston.

That said, window strikes by themselves may not drive bird declines in Massachusetts. Window strikes are an additional stressor, however, on top of a laundry list of human-caused threats to bird populations. In today’s world of climate change, habitat loss, and invasive species, every bird counts– which is why window strikes are worth understanding.

Cities Are Only Part of the Problem

Outside the study areas in Downtown Boston, our volunteers reported many casualties even without focused searching. Their findings emphasize what other studies already suggest: window strikes are at least as much of an issue at single-family homes and low-rises as they are at tall urban buildings.

The good news is that there are lots of ways to make your home or office windows bird-safe. Here are some tips:

Screens on windows are the cheapest and perhaps simplest option: they break up reflections and also provide a springy barrier that collision-bound birds can bounce off of.

Where screens are impossible, consider buying or building an Acopian Bird Savers (hanging lengths of bird-deterring string). Learn how to build your own here!

Window decals only work when spaced less than 2” apart vertically and 4” apart horizontally, but when used correctly, they’re another great option. Certain kinds are transparent to human eyes, so even narrowly-spaced ones won’t interrupt your view.

Installing UV-reflective patterned glass like Ornilux is extremely effective, and by far the most discrete option– but also the most expensive.

Finally, turning unneeded lights off at night helps conserve energy and avoid drawing birds into strike-prone areas.

(Disclaimer: Mass Audubon has no affiliation with any of the above vendors).

Joan's Video

Joan Walsh: In the field at Great Gull Island

Ever wonder what we do in the field? Check out this video of Bertrand Chair, Joan Walsh, marking Roseate Tern nests on Great Gull Island, NY. Jeff Collins, Director of Conservation Science at Mass Audubon, asked Joan to share what a day in the field looks like on Great Gull Island. Joan has worked on Great Gull Island off and on for 39 years. The island is home to 18,000 Common Terns and 3,000 federally endangered Roseate Terns.

When she reaches a Roseate Tern nest box, if there is a nest, she marks it with GPS coordinates and records data on eggs and nestlings. Roseate Terns prefer to nest under vegetation or in man-made nest boxes. The work seen in this video was part of Joan’s 5-day effort to mark nests.

Important: It is illegal to approach or disturb a nest without a permit. Joan works under a permit to research Roseate Terns and Common Terns.

*Video footage was sped up when Joan is doing the nest box marking to fit more content in 1 minute. Joan is not that speedy!

Barn Swallows at Conte Refuge, Hadley

Since mid-May, Jon Atwood has been collaborating with US Fish and Wildlife Service (USFWS) managers at the Silvio O. Conte National Fish & Wildlife Refuge in a study aimed at monitoring Barn Swallow use of an abandoned stable located on the refuge’s Fort River Division in Hadley, MA.

Barn Swallows © Kim Caruso

Barn Swallows Are Declining in Some Places and Increasing in Others—Why?

Barn Swallows, along with many other aerial insectivores, are showing serious population declines in many portions of their North American range. However, the causes of these declines are uncertain. Pesticide impacts associated with large-scale agriculture, reduction of flying insect populations, landscape conversions, habitat changes along the species’ migration pathways, unknown impacts on the species’ Central and South American wintering grounds, and loss of barns and similar structures that are often used as nesting sites have all been postulated as possible factors.

The question is complicated—Barn Swallows in the northern portions of their range are mostly declining, while those in the south and west are increasing. If there is a single explanation, presumably the “answer” needs to make sense throughout that extensive range—why are populations increasing in some areas but decreasing in others?

Barn Swallow population trends in North America. Red areas highlight substantial declines, while blue areas reflect increasing populations. From USGS Breeding Bird Survey data, 1966-2015.

Understanding Barn Swallows in MA

In this year’s work in Hadley, our focus is on starting to understand the population dynamics of Barn Swallows nesting in this portion of the Connecticut River Valley. About 30 pairs of swallows have nested in the abandoned stable in the last few years, making this site one of the largest known colonies in Massachusetts. Unfortunately, as is often true of aging barns in New England’s agricultural landscape, the stables in Hadley are in serious disrepair, and the Fish and Wildlife Service has recommended that the building be taken down over a several year period, while simultaneously making efforts to attract the birds to alternative nesting sites.

Mass Audubon and USFWS are studying this situation to collect information that will help inform the policy decisions. This work includes regular censusing of nesting efforts in the stables and banding of nesting adults. At the end of the season we will issue a final report that details our findings, so stay tuned for more information.

Foresters for the Birds: Starting work at Elm Hill

Habitat management work at Elm Hill Wildlife Sanctuary is underway! Elm Hill is our demonstration site for our Forestry for the Birds program, which we’re using to exhibit techniques for improving bird habitat with sustainable forestry.

Invasive plant removal has begun, and forestry operations will commence in a few short months. Following years of fundraising, planning, site preparation, data collection, and a minor setback, it’s all finally coming together.

Eastern Towhees like young forests and dense scrubby habitat. Photo by: Marco Jona

Bird-Friendly Forestry

Foresters for the Birds works with private landowners and consulting foresters to create and enhance bird habitat using sustainable forestry practices. In order to lead by example, Mass Audubon decided to showcase such practices at Elm Hill. Besides creating great habitat for birds, the site will be used to educate and engage with landowners, conservation organizations, state agencies, forestry professionals, and the general public.  In fact, we’ve already hosted a handful of events at Elm Hill, attracting about 100 people so far.

Young Forests and Tree Diversity Are Key

Following a Foresters for the Birds management plan, this round of management will create about 30 acres of young forest, a habitat type crucial to a group of birds categorically in decline, such as Eastern Towhees and Chestnut-sided Warblers. We will also improve tree species diversity in about 100 acres of older forests, and encourage layers of shrubs and saplings to benefit species such as Wood Thrushes and Black-throated Blue Warblers.

Creating Climate-Resilient Forests

Climate change has already started to affect Massachusetts forests, which complicates management strategies for bird habitat. The ranges of plant and insect species that certain birds depend on are shifting, and some are inevitably less resilient to an unstable climate. Bearing this in mind, we worked with the Northern Institute of Applied Climate Science (NIACS) to ensure that our management actions at Elm Hill were climate-smart. With their help, we’re identifying opportunities to adapt the forest– and the birds it supports– to future climate conditions.

Please stay tuned for opportunities to visit Elm Hill, where detailed discussions of our bird habitat and climate adaption actions can take place. There’s much more to it beyond what can be communicated in a short blog post!

Bird-Themed Summer Camps

Budding bird enthusiasts love our summer camps, many of which offer special bird-themed sessions. Check out the following opportunities for kids and teens to learn about birds this summer!

Connecticut River Valley

Raptor Camp (ages 12–16)

June 24–28 Ÿ Arcadia Wildlife Sanctuary, Easthampton & Northampton

Set out to discover birds by foot and canoe at Arcadia and local birding hot spots. See bird banding up close, and learn how to identify birds by sight and sound. An entire day will be devoted to birds of prey.

Greater Boston

Wild about Birds: Curiosity Club (ages 4–5)

Wild about Birds: Naturalists (ages 7–8)

July 22–26 & July 1–3 Ÿ Broadmoor Wildlife Sanctuary, Natick

Explore what makes a bird a bird, play a game about bird migration, sing in a birdsong choir, and get an up-close look at birds through a telescope. Look inside nest boxes for baby birds and empty nests and meet live birds with an ornithologist.

Wild about Birds: Explorers (ages 9–10)

Wild about Birds: Voyagers (ages 11–14)

July 1–3 Ÿ Broadmoor Wildlife Sanctuary, Natick

Learn when to use binoculars, a birding scope, or your bare eyes to watch for birds. Meet with an ornithologist to learn how scientists study and track birds that migrate. Head off-site to find birds in different habitats, investigate adaptations that allow birds to survive in different environments, and track species and diversity in a bio-blitz.

That’s Wild: Owl Extravaganza (ages 4–6, 7–8)

July 8–12 Ÿ Museum of American Bird Art, Canton

Back by popular demand: owls soar into camp again this summer! Spend the week on the prowl for owls. See live owls up close, learn about their special adaptations, and create art based on the different owl species found in Massachusetts.

Coastal Birding Adventure (ages 13–17)

August 19–23 Ÿ Drumlin Farm Wildlife Sanctuary, Lincoln

Travel through the unique coastal ecosystems of Massachusetts, and search for and learn about the unique birds that inhabit them. Spot warblers in Pine Barrens, plovers and sandpipers in the dunes, and terns over the ocean. Check out the latest rare sightings and search for early migrant visitors.

North Shore

Winged Wonders (ages 7–8, 9–11)

July 29–August 2 Ÿ Joppa Flats Education Center, Newburyport

Using binoculars, scout Parker River National Wildlife Refuge for all kinds of wading marsh birds and soaring birds of prey. In the forest at Ipswich River Wildlife Sanctuary, listen for songbirds on a forest hike, and climb the observation tower and Rockery Grotto. Back at Joppa Flats, get ready for a live wildlife visit from a local raptor rehabilitator, and dissect owl pellets!

Cape & Islands

Fabulous Fliers (ages 7–8)

July 15–19 Ÿ Felix Neck Wildlife Sanctuary, Edgartown

Why do birds flock together? How do they fly? And why do they sing? Identify and explore adaptations of the many fabulous fliers at Felix Neck, including the osprey, songbirds, and shorebirds.


Bird-a-thon and Southern Overshoots

Bird-a-thon, Mass Audubon’s annual competitive birding fundraiser, is fast approaching on May 10-11! Spring migration is heating up right on time for the big day– with a few surprises in the mix.

This year’s migration has been marked by an unusual number of southern species overshooting their breeding grounds and ending up in Massachusetts. These “southern overshoots” ride the winds to our state and only stay for a few days before returning to their normal ranges in the mid-Atlantic and southeast, but it’s fun to see them while they’re here!

The Slingshot Effect

Southern overshoots require more than just south winds over Massachusetts. Birds aiming for southerly climes only get a boost into our state when winds line up just right across the eastern seaboard in what’s called the “slingshot effect.”

This pattern starts with strong wind blowing birds offshore over Florida, the Gulf, or the Southeastern US. These birds normally return to land unless they meet a strong south-to-north air current over the ocean, which “slingshots” them northward until they meet the coast of New England. A heavy west wind over the entire mid-Atlantic region can also prevent them from returning to shore until they make landfall in our region.

Here are just a few of the species that rode “slingshot winds” up to Massachusetts in the past month, with maps comparing sightings from April 2018 with April 2019:

Summer Tanagers

Summer Tangers are birds of humid thickets in the southeastern US. Last April, none were reported in mainland Massachusetts. This year, two were seen in Plymouth, one on Plum Island, and a handful as far north as Maine!

Summer Tanager sightings – April 2018
Summer Tanager Sightings – April 2019

Hooded Warblers

Another bird prone to the “slingshot effect,” Hooded Warbler been unusually numerous this year, including late into the month. Here’s the same comparison between this and last April:

Hooded Warbler sightings – April 2018
Hooded Warbler sightings – April 2019

Blue Grosbeaks

Similarly, last April produced just two reports of Blue Grosbeak, a grassland bird of warmer climes. This April, there were no less than 12!

Blue Grosbeak sightings- April 2018
Blue Grosbeak sightings – April 2019

Sign up for Bird-A-Thon and Find Southern Wanderers!

Bird-a-thon is coming up on May 10t-11. Make sure to join a Bird-a-thon team if you haven’t yet! Then, find out which award you’re competing for, plan your strategy, and tell your friends who you’re raising money for!

If the current forecast for Bird-a-thon weekend holds, some overshoot species will no doubt be a key piece of the winning checklists. Southern overshoots get most attention from in-the-know birders in late April, mostly because it’s so striking to see them arrive even before our more common spring migrants show up. But conditions for overshoots can persist into early May, when southern birds show up at coastal thickets and migrant traps like Mass Audubon’s Marblehead Neck Wildlife Sanctuary and Mount Auburn Cemetery in Cambridge (psst– that’s a hint!)

If you’re joining us for Bird-a-thon, good luck, and may the best team win!

Meadowlark Project 2019: Birding for Conservation

Now in its third year, the Eastern Meadowlark Project is a great way to support bird conservation by simply going birding.

By checking for meadowlarks at a list of sites and entering observations on our project webpage, citizen scientists help piece together the reasons for this species’ decline.

Eastern Meadowlark (photo by Phil Brown)

We know that meadowlarks are in trouble. Between 1974-2011, meadowlarks disappeared from over 78% of their Massachusetts breeding sites, according to Mass Audubon’s Breeding Bird Atlas.  This decline is only partially explained by meadowlarks’ habitat requirements.

Our 2018 volunteers found meadowlarks at just 3 sites out of over 100 protected grasslands across the state. While meadowlarks do persist at a handful of known agricultural sites outside our survey areas, these results suggested they aren’t using all of the habitat ostensibly available to them. So, while we know habitat loss is a major factor, we also know that it’s not the only part of the meadowlark decline equation.

Our next step is to check sites where meadowlarks were historically seen–including areas that might not be textbook habitat for them. This year, surveys will take place at sites where Eastern Meadowlarks were spotted during the past two Breeding Bird Atlases (1974-1979 and 2007-2011). This will help us both establish where meadowlarks have disappeared from their historical range, and what kinds of habitats meadowlarks are using aside from natural grasslands.

Go Birding—For Science!

First, visit our Anecdata webpage to select sites where you can help look for meadowlarks.  You’ll need to create an account by clicking “register” in the top right corner and creating a username and password. Then, return to the meadowlark project page and click “join project” (just under the photo of the meadowlark). To view a map of sites, click on “add an observation,” then click “use a hotspot” in the upper left, and then click “map.”  Finally, be sure to sign up for the hotspots you choose on the signup list mentioned in the project description!

To keep our data uniform and reliable, a volunteer should survey a site three times between April 10 and June 15, for any 10-minute period between 5:00 am and 9:30 am.  Not all of our sites may have meadowlarks, and that’s perfectly fine— knowing where they aren’t, and figuring out why, is just important to us as knowing where they are.

Thanks for helping us help grassland birds– and good luck finding meadowlarks!

Help Us Learn About Bird-Window Strikes Downtown

Calling all citizen scientists near Boston!

Mass Audubon needs your help monitoring an underappreciated threat to migratory birds: window collisions. We’re looking for volunteers to collect data on bird-building collisions and rescue birds that survive a strike.

A Black-throated Green Warbler that died on migration from a window collision.

The Problem

Window collisions are a surprisingly significant source of bird mortality in the US, causing several hundred million casualties annually.

Birds struggle to distinguish reflections from reality, and often strike glass windows that reflect the sky or nearby greenery. City lights also confuse night-migrating birds, which use the stars to navigate, and which often land near sources of light pollution. Many window strikes occur as birds try to re-orient in the morning, after being drawn in to an unfamiliar concrete jungle.

How to Help

The Avian Collision Team (ACT) is a new volunteer initiative to get as much data as we can about building strikes in Boston. We want to understand the scale of the problem in Boston, where the trouble spots are, and which species are most affected.

The program runs from April 13–June 4. Volunteers need to sign up for 1-4 weekly shifts, Saturday–Tuesday, from 8 am to around 9 am.

We are looking for two kinds of volunteers:

1. Monitoring volunteers who will walk predetermined routes to collect deceased specimens, fill out data sheets, and occasionally rescue live birds.

2. Transport volunteers who can pick up specimens from monitors and bring them to a collection site at Harvard. Drivers will also bring occasional injured, live birds to Tufts Wildlife Clinic in Westborough as needed.

Similar programs have shown that in parts of some cities, there are practically no casualties. In others, certain buildings can kill a dozen birds a day during peak migration. Scientists have developed guidelines for what makes buildings especially dangerous to migrating birds, but they’re still pretty rough. The best way to know where and to what extent there’s a problem in Boston… is to check! 

If this sounds interesting, sign up here!