Category Archives: Research and Monitoring

Chemical Clues Help Track Migratory Birds (Part I)

Photo © Will Freedberg 2016

Where did this Scarlet Tanager spend the winter? A birder might correctly say “South America,” but where specifically? How can we know the country, the province, the latitude and longitude?

In fact, chemical signatures in feathers, blood, and muscle tissue tell the story of where a bird has been, and what it’s been eating. Over the past couple of decades, ornithologists and chemists have learned how to read into birds’ life histories by analyzing the isotopes that have built up in its body.

What’s An Isotope?

An isotope is just a lighter or heavier-than-normal atom of a given element (like hydrogen, carbon, or nitrogen).

Two kinds of particles contribute to an atom’s mass: protons and neutrons. Most atoms of any element have the same mass because they share the same number of protons and neutrons. While the number of protons in an atom define its identity and properties, adding a neutron to an atom rarely changes its behavior (other than its mass). For example, a bird will suffer no ill effects if a bird’s body contains an abnormal ratio of carbon 13 to carbon 12 (that is, “normal” carbon versus heaviercarbon with an extra neutron).

“You Are What You Eat”

Like any living beings, birds incorporate nutrients from their food into their bodies as they grow. The atoms in these nutrients, some of which will end up in a growing bird’s flesh and blood, exist in different isotopes depending on a variety of factors.  Some isotopes are more common at certain latitudes, or in certain groups of plants, or at a certain level of the food chain. So, a bird’s body will contain different proportions isotopes depending on its location and diet. By analyzing the ratio of one isotope to another in a bird’s body, scientists get an idea of where individual bird is from and what it’s been eating.

Advantages To Isotope Studies: Scale And Cost

Isotopes are particularly useful in long-term or large-scale studies. Isotope analysis ismuch cheaper and often less invasive than attaching geolocators to migratory birds, many of which are too small to carry a transmitter (meaning someone must recapture the bird to recover tracking data).

Studying isotope ratios in natural history museum specimens also provides unique historical perspective on how birds’ diets or ranges have changed over time.

In the next post, we’ll go over a few studies that have used isotopes to track long-term changes in bird diet or established where populations of breeding birds overwinter. Stay tuned!

 

 

 

 

Partnerships for Plovers: Birdlife International and Mass Audubon

An endangered Piping Plover at one of Mass Audubon’s coastal sanctuaries. (Photo by Will Freedberg)

 

This year, Mass Audubon is partnering with BirdLife International to help coordinate migratory shorebird conservation across the hemisphere. By joining the Friends across the Flyway initiative, Mass Audubon can link up with conservation organizations along the Atlantic Flyway to protect species shared across borders.

 

Connectivity Counts

For birds whose ranges cross international borders, it’s crucial that regional conservation groups coordinate with each other. All threatened or endangered shorebirds in Massachusetts spend half the year in migration or at their wintering grounds. Every year, Piping Plovers, Red Knots, and Least Terns migrate to Mexico, the Bahamas, and even Argentina—and they depend on stopover habitats to feed and “refuel” along the way.

Removing just one link in this chain of habitats can spell the demise for an entire population. When making a conservation plan, biologists like to emphasize “habitat connectivity,” or keeping open routes between areas where a species lives. With New England’s shorebirds, this means more than preserving a physical link between protected areas—it means conserving breeding habitat in Massachusetts, wintering habitat in the Southern Hemisphere, and key stopover sites birds use while migrating in between.

 

How We Help In Massachusetts

Mass Audubon’s Coastal Waterbird Program approaches local shorebird conservation from all possible angles. Firstly, Mass Audubon puts boots on the ground—or rather, on the sand—to monitor shorebird populations and develop science-based conservation plans. Then, we work with local and state governments to put those plans into action. This includes setting goals for shorebird recovery, res-siting energy projects, and helping lawmakers identify beaches where shorebirds are threatened by offroad vehicles.

So far, the program has been a huge success! Piping Plover numbers have quintupled in Massachusetts since the program started in 1984.  American Oystercatchers, once a rare sight in our state, now number over 200 nesting pairs.

 

Partnerships Save Species

We’re excited that our Coastal Waterbird Program is linking up with BirdLife and its partners! This suite of organizations can pool resources to protect habitat and produce research on these shorebirds’ global needs. To learn more about Friends across the Flyway, check out BirdLife’s video on Rowan, the cute Red Knot.

Long Legs and Filmy Filigree: A Visit to Kettle Island

Colonial-nesting waterbirds are always fascinating, and because so many species nest on remote or hard-to-get-to islands, a visit to a colony typically represents an adventure.  And so it was when six intrepid staff members and volunteer bird counters visited Mass Audubon’s Kettle Island (a Massachusetts Important Bird Area) off the coast of Manchester-by-the-Sea last week.  A 17 acre uninhabited rocky island approximately a mile offshore, much of the island is vegetated with a dense cover of low trees, shrubs, thorns, and copious amounts of poison ivy. One can view the island’s birdlife from a boat, but landing is prohibited in order not to disturb this important colonial waterbird nesting site.

Kettle Island bird team ©Craig Gibson

The purpose of the island visit was to census and survey the breeding long-legged wading birds that have nested on the island for several decades.  The visit was part of a survey project initiated last year to assess the overall status and ecology of a number of islands off the Essex County coast, and also part of a greater coastal waterbird survey being jointly conducted by the U.S. Fish & Wildlife Service and Mass Wildlife.  One of the largest colonies in the Commonwealth, Kettle Island currently hosts Great Egrets (194 pairs), Snowy Egrets (99 pairs), Little Blue Herons (4 pairs), Black-crowned Night-Herons (30 pairs), and Glossy Ibises (9 pairs).  In addition, the island sanctuary is currently home to 2 pairs of American Oystercatchers, 51 pairs of Herring Gulls, and 79 pairs of Great Black-backed Gulls.

Little Blue Heron ©Craig Gibson

One of the magical aspects of visiting a breeding island at this season is seeing some of our most spectacular breeding species in their full breeding plumage—plumages that brought many species virtually to their knees in the heyday of the millinery trade during the late 1800s and early 1900s when their feathery filigree was central to the egregious fashion industry of the day.  Not only did the excesses of this worldwide feather lust bring the founding mothers of Mass Audubon to rise up in outrage in 1896, but it was this same excessive slaughter of egrets, herons, and other birds that ultimately led to the establishment of the Migratory Bird Treaty Act 100 years ago this year.

Great Egrets ©Craig Gibson

Thanks to these two historic conservation milestones, today bird watchers, photographers, artists, and everyone who enjoys beautiful living things is able to see these handsome species seasonally inhabiting the coastlines and salt marshes of Massachusetts when they are not nesting on their remote island colonies.

Great Egret chicks ©Craig Gibson

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

Patriots on the Move: tracking the migration of Great Shearwaters

While New England football fans are anxiously following the fortune of the New England Patriots, ornithologists at the Stellwagen Bank National Marine Sanctuary are tracking the trans-equatorial movements of Great Shearwaters (individuals in this year’s group are named after Patriots players).

Through the use of sophisticated satellite technology, tiny transmitters now have the capacity to follow the movements of birds and secretive mammals more than a hemisphere away practically in real time.

Great Shearwater ©Peter Flood

Followers of Distraction Displays may recall that in late summer seabirds called Great Shearwaters made headlines when exceptional numbers were observed feeding on many thousands of Menhaden (small forage fish) in the surf-line at Provincetown on the tip of Cape Cod. Although most of these shearwaters have long since retreated toward their nesting grounds on the remote archipelago of Tristan du Cunha deep in the South Atlantic Ocean, scientists nonetheless now know precisely where some individuals are located!

A size comparison of one of the solar PTT transmitters used in the project and a standard U.S. penny. ©NOAA/SBNMS

While satellite tracking has been used to monitor wildlife for 20 years or more, the weight and size of transmitters today makes it possible to follow wildlife significantly smaller than eagles and bears. This summer, waterproof transmitters called PTT (Platform Transmitting Terminal) tags weighing only 12 g and manufactured by Microwave Technology were affixed to shearwaters off Cape Cod during the month of August.

Of nine tags originally affixed to Great Shearwaters and one to a Sooty Shearwater this summer, one is still generating round-the-clock signals from Argos satellites orbiting the earth at approximately 528 miles above the ground. The unique signals generated by the transmitters are regularly received by Argos and eventually made accessible to the researchers who are mapping the movements of the shearwaters. Needless to say the technology involved is complex, but the information gathered is elegant.

All 10 tagged shearwaters as of 1/4/2018. ©NOAA/SBNMS

The 10 shearwaters tagged this summer were all named after New England Patriots players. Of the 10 tagged shearwaters, only Gronkowski’s transmitter was still sending signals on January 2, 2018. Gronkowski crossed the equator on December 19, and as of Jan. 2 was at 16.5 degrees South in deep water (>2000 meters) off the coast of Brazil near Banco Minerva—a semount <100 meters deep. Go Gronk!

Gronkowski as of 1/2/2018 ©NOAA/SBNMS

Cooks crossed the equator on December 12, but its transmitter stopped working on Christmas Eve at 27 degrees South in deep water (>2500 meters) off of Paraguay.

Cooks 12/24/2017 ©NOAA/SBNMS

McCourty’s tag stopped working on December 19, hours after crossing the equator. Edelman was still in the mid-Atlantic on Dec 12, and unfortunately Brady’s Sooty Shearwater transmitter cut out while the bird was off Morocco in mid-October.

Edelman 12/12/17 ©NOAA/SBNMS

All of the tagged shearwaters were aged by plumage to be either one or two years-old, and most will not likely return to Tristan du Cunha this winter because few are likely to attain breeding age until they are at least 5-6 years-old. These sub-adult individuals will very likely remain on the Patagonian Shelf until March/April before beginning their northward migration, which will initially bring them up the east coast of South America before reaching North Atlantic waters and the Gulf of Maine.

Having the ability to track individual Great Shearwaters in this way affords ornithologists not only a fine way to chart how this highly pelagic seabird uses the entire Atlantic Ocean in the course of a year, but also a way to map prime foraging and other concentration areas while they are in Gulf of Maine as well as elsewhere in the Atlantic Ocean. This information ultimately enhances the ability to identify oceanic regions of highest conservation concern. Read more about this fascinating project >

Another successful year for The Bobolink Project

Bobolink © Allan Strong

We are proud to share a final report on what The Bobolink Project accomplished during the summer of 2017. But before we share the results, we first and foremost thank our donors. With their financial support, conservation interest, and promotional efforts, The Bobolink Project would not exist. This is very much a grassroots conservation effort—pun intended—and we are deeply appreciative of our donors’ support.

We also thank the farmers who applied to and participated in the project. Without them the habitat for grassland birds would not exist. We are glad that they are conscious of the birds on their fields and that they are willing to participate in a solution that allows them to grow a “crop” of grassland birds without compromising their financial stability.

Donations and Farms Enrolled

In the months leading up to the 2017 field season, we raised just over $38,000 to support the project’s objectives, and 99% of this donation pool was given directly to the participating farmers. Based on the fixed-price reverse auction, the final bid that was accepted from the farmers was $60/acre.

With this financial support we were able to enroll about 630 acres distributed among 17 farms—13 located in Vermont, two in Massachusetts, one in New Hampshire, and one in New York.

Bobolink (female) © Allan Strong

Successful Breeding Pairs and Fledglings

The project state coordinators surveyed the fields this summer to measure the success of the program for grassland birds. They estimated that there were about 294 pairs of Bobolinks on the enrolled fields. Using what we think is a conservative estimate of 2.79 fledglings per breeding pair, we estimate that 820 Bobolink young were produced as a result of the project’s 2017 efforts.

The number of fledglings nearly doubled from 2016 to 2017 even though the amount of protected acreage increased by about 20%. The huge increase in fledgling numbers is due in large part to one of the participating farms in particular, which consisted of 146 acres with many nesting Bobolinks.

The 2017 breeding season was also especially wet in many parts of the northeast. Increased amounts of rain typically means more invertebrates (e.g., insects) for Bobolinks to eat. This enhancement of breeding conditions could have influenced the higher number of Bobolink pairs and fledglings estimated this year.

What We Left On the Table

Another important aspect of this project concerns what we were unable to accomplish.

In 2017, we had to reject applications from 19 farmers who had submitted bids that exceeded what we were able to support from our donation pool. In other words, about 615 acres of offered habitat was lost because we needed more donations.

Of course, it’s wonderful that we succeeded in protecting 634 acres of grassland bird habitat! But the fact that we had to “leave on the table” a total of 615 acres—land that otherwise might have been protected—is a sobering thought. Remember, the more donations we collect, the more land we can protect from haying. We hope this reminder motivates new and previous donors alike to support the Bobolink Project in 2018.

In fact, contributions toward next year’s efforts can be made now—even while the birds themselves are busily heading toward South America! It’s never too early to make a donation, and your gift will be set aside for the 2018 nesting season.

To get the latest information follow us on Facebook, check out the website, or subscribe to our e-newsletter.

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!

The Treasure Islands of Essex County

by Chris Leahy, Gerard A. Bertrand Chair of Natural History and Field Ornithology emeritus

Halfway Rock © Chris Leahy

There is something about islands. Their remoteness generates a certain mystique.  Even islands inhabited by people have an aura of “away-ness,” and uninhabited ones stimulate visions of hidden treasures of one kind or another. There is also an ecological significance to islands: their plants and animal communities are often different from those of even nearby mainlands; their isolation from other populations promote evolutionary change; and they may act as refuges for certain species because they are hard to reach by predators.

The coastal waters of Essex County from Nahant Bay to Cape Ann are dotted with more than 50 islands ranging in size from small rocky “skerries” which are nearly submerged at high tide to the well-wooded 83-acre Great Misery Island, two of them populated at least seasonally. In 2002 these were formally designated as the Essex County Coastal Birds Islands Important Bird Area*, due to their breeding populations of water birds that rarely nest on the mainland, including a number of rare or uncommon species.

Straitsmouth Island © Chris Leahy

This summer Mass Audubon’s Conservation Science Department, supported by a grant from the Nuttall Ornithological Club, and the help of several generous private boat owners began a survey of these islands with the following basic objectives:

  • Developing a comprehensive understanding of past and current bird survey efforts, data sources, and management activities.
  • Completing an assessment of current breeding bird activity on the islands.
  • Identifying existing stresses such as human use, presence of rats and other predators, vegetation change, and climate vulnerability.
  • Developing recommendations for future management in support of the breeding birds.
  • Raising public awareness of the importance of these islands through programming and networking with state and regional conservation entities.

The survey has already turned up a number of previously unrecorded breeding sites for wading birds and American Oystercatcher.  We will be publishing more detailed results in the near future.

 

*An Important Bird Area (IBA) is an area identified using an internationally agreed upon set of criteria as being globally important for the conservation of bird populations. The program was developed and sites are identified by Birdlife International based in Cambridge, England. Currently there are over 12,000 IBAs worldwide and 79 in Massachusetts.

 

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

In the Field: Elm Hill

Scarlet Tanager © Ruby Sarkar

Past blog posts about our Elm Hill Sanctuary – a Foresters for the Birds demonstration site—have largely discussed the planning of forestry practices to manage and enhance bird habitat.  We kicked the project off last fall and winter, when our migratory birds were hundreds or thousands of miles away.  So, until spring arrived, we were not able to work much with the birds themselves.

A primary focus of the program is indeed birds and their habitat, so it is important to assess how effective any implemented forestry practices are.  This enables us to make adjustments to future management and maximize the benefit for birds.  We do this by monitoring how the birds respond.  At the earliest, on the ground management at Elm Hill will not happen until this coming winter.  However, we will need to compare the future bird response to current, baseline conditions.  A before-and-after, if you will.

Late May through early July is the ideal time to sample breeding birds.  Migration is over, so all the birds have arrived and will likely remain through the season.  They are on breeding territories and actively singing, which helps us to detect their presence.  During this time we can begin to answer some important questions.

For example, which species are present, and what are their general habitat preferences?  How many species are present?  How many individuals of each species are present?  Is a particular species absent that we may have expected?  Answering questions like these help us to characterize the current bird community.  Answering the same questions after habitat management will help us assess just how effective our efforts were.

Wood Thrush nest © Michael Ross

This is why, with the help of volunteers, Sheila Carroll and Mark Lynch, we recently completed a series of point count surveys at Elm Hill, all within areas that are slated for management in the near future.  With this initial information in hand, we will eventually see how things change after management, which is geared towards helping species in need of conservation action.  The next step will be to dig into the data, and some results will be shared in future Elm Hill updates.  Stay tuned!

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

The Bobolink Project: 2017 season update

 

Male Bobolink © Allan Strong

The Bobolinks are arriving in New England and we’re finalizing the contracts with our participating Bobolink Project farmers. Thanks to the generosity of our Bobolink Project donors, we can protect over 630 acres of farmland this year! In return for some compensation, the Bobolink Project farmers will delay mowing on their hay fields until the young grassland birds have had time to fledge.

As in past years, we had more acres submitted into the project than we could cover with the available pool of donations. This year, we received 40 applications from farmers in Vermont, Massachusetts, New Hampshire, Maine, and New York—but our donation pool, as of April 1st (our deadline for donations), could cover only 17 of the farmers’ fields. This may sound disappointing, but we are able to cover 20% more acres this year at a lower per acre price of $60 (vs. $75 last year).

We are glad that the project is continuing to grow and look forward to welcoming grassland birds to fields enrolled in the program this summer and sharing our results with you. Keep up to date with The Bobolink Project by signing up to the mail-list or follow us on Facebook.

The Bobolink Project donations are accepted all year. The 2018 donation pool is already growing: since April 1st we have received over $8,000 in donations that will be saved for next year. Donate now to help us protect more acres and birds next year.

 

Eastern Meadowlark Citizen Science Project May 15–June 15

Eastern Meadowlark © Phil Brown

Calling all birders and bird enthusiasts!

We have launched a multi-year citizen science project to study Eastern Meadowlarks. The project aims to collect presence-absence data for Eastern Meadowlarks at randomly selected sites throughout Massachusetts from May 15 to June 15, 2017. Eastern Meadowlarks are in serious decline, both in Massachusetts and elsewhere in North America, and in order to better help this species we need to know more about their status in Massachusetts. The data collected through this project will provide valuable information about this species’ current distribution in the Commonwealth, and will form the basis for a better assessment of meadowlark habitat requirements and future conservation needs.

To get the information we need it is critical that we get help from citizen scientists. There are a lot of potential sites where Eastern Meadowlarks could be nesting, but there are only a few of us! The results of this work will help us develop models for use in evaluating potential sites that have not been visited.

Project data can be easily entered through the Anecdata website on a computer or in the field on a mobile smartphone device. The surveys required are simple and quick (10 minutes!) to do. We’ve provided our citizen scientist volunteers with “hotspots” where we specifically need a volunteer to do a meadowlark survey on three separate dates (with preferably at least 3 days in between each date) during the period of May 15 and June 15. Many of these hotspots will likely not have Eastern Meadowlarks, but knowing where Eastern Meadowlarks are not is just as valuable for scientific analysis as knowing where Eastern Meadowlarks are.

More information about how to get involved is available on the project website.

Not familiar with Eastern Meadowlarks? Check out our quick guide and listen to their song.

Questions? Contact us at birdconservation@massaudubon.org.