Tag Archives: eBird

Barrow's Goldeneye

Can half the birds on earth be found in a weekend?


What if every birdwatcher in the world submitted their bird observations from a single weekend into a single, centralized database? How many of the world’s birds can be recorded on a single weekend in February? This weekend, birders from around the world are using eBird to run this experiment worldwide for the second global Great Backyard Bird Count. Last year 41% of the world’s birds were detected; this year we’d like to shoot for 50%. But to succeed, we’ll need the readers of Birding Frontiers to help out, both by entering data and by spreading the word about the count.

Team eBird

If you have never tried eBird before, there has never been a better time to get involved. Take part in this global initiative to see how many birds can be recorded in a single weekend.

Great Gray OwleBird allows any birder worldwide to submit data to a centralized database and to view these data on a variety of eBird data exploration tools. More importantly for the birder, the free website provides the services of the best listing and record keeping software, automatically tracking your life list, Western Palearctic list, country lists, state or province lists, county lists, year lists, patch lists, site lists and garden lists. All contributors are acknowledged in our Top100, a fun way to see who is seeing the most species and submitting the most checklists anywhere in the world. As more users join each year, the accuracy and extent of the data get better and the database gets less biased towards North America, where eBird began in 2002.

Access to eBird data is free for anyone; the entire dataset of over 165 million records—or any subset thereof—can be downloaded by birders, researchers and conservationists. This philosophy is fundamental to the project and makes eBird a powerful tool for bird recording in dozens of countries that don’t have an existing framework, database or team to organize it. Golden-browed ChlorophoniaData quality is always a concern and we work hard to make it better every day. We have a team of more than 600 of the top birders in the world who already help with this system and are always interested in welcoming new regional experts willing to lend a hand. The system works by employing date-specific regional filter to identify rare sightings and giving our reviewers easy tools to follow up on rarities (more on eBird data quality). If you’re interested in helping, let us know at: eBird@cornell.edu.

eBird has data entry apps for iPhone and Android—known as BirdLog. The European version is free and works throughout Europe. The Great Backyard Bird Count version is also free and works worldwide for the next 60 days. Global BirdLog is available for a price that directly supports these apps.

Snow Petrel

So whether you log birds from your garden or from some far-flung country with comparatively few birders, we invite you to enter a few checklists from Friday the 14th through Monday the 17th. Try to put in at least one checklist in a day. If you get out birding, try to put in site-specific lists from the places you visit during the day (rather than one list from multiple sites). Yeah, it’s a bit more work to keep specific site lists, but we think that after you explore the results in eBird, you’ll agree the effort is well worth it.

Follow the weekend progress at eBird’s Location Explorer. Just type your country, state, or county here and see what eBird has and what you can contribute.

Plains-wanderer

What are you waiting for? Enter your observations now!

Vagrant hunters on an island vagrant trap off Massachusetts checked a small marsh specifically for Purple Gallinule in October 2011 and surprised themselves by finding this one! Photo by Ryan Schein

American Purple Gallinule Vagrancy in the North Atlantic, November 2013 – February 2014


American Purple Gallinules are champions of long-distance vagrancy, with records from as far north as Iceland, as far south as South Georgia Island, as far west as the Galapagos Islands, and as far east as Italy and South Africa. This species, and many other rails, are habitat-based dispersalists, adapted to respond to ephemeral habitats and with the machinery to travel long distances. This winter has seen a big influx. What’s driving this?

Team eBird

In late fall 2013 and winter 2014 there have been a surprising number of records of this species far out of range (originally compiled by our friend Louis Bevier and subsequently amended by Teams BirdCast and eBird): 7-11 November 2013, Parque Monsanto near Lisbon, Portugal (see more here; taken in to care 11 Nov and died 13 Nov); 17 November 2013, Seal Island NWR, Maine fide Juanita Roushdy and John Drury; 8 December 2013, Clarenville, Newfoundland8 January 2014, Trenton, Maine, thanks to Michael Good; 9 January 2014, Clermont, NJ; 10 and 13 January 2014 from Bermuda; 19 January 2014, Maccallum, Newfoundland fide Bruce Mactavish; 21 January from Bermuda; 29 January 2014, Kettle Cove, Maine (apparently long-dead) fide Richard Jones via George Armistead; 30 January 2014, Iceland; and 2 February 2014, Mullett peninsula, County Mayo, Ireland. That’s 11 far-flung records of birds that were found (American Purple Gallinules are not easy to find!), with three of them crossing the Atlantic!

Two obvious questions come to mind. First, how did they make it across the Atlantic? And what were they doing moving in the first place? We offer an in-depth analysis of the effects of cold, drought, and wind and air parcels on BirdCast and a quick summary below.

Winter range

eBird distributionThe temperate zone winter range for American Purple Gallinule is primarily peninsular Florida, Mexico and Central America south to northern South America, and the Caribbean, with additional populations farther south in South America breeding during this time. The map at left shows this typical distribution from eBird observations of the species from November to February. Of note in this map are occasional winter records away from Florida in the US and frequent records of the species from central Florida south to the Florida Keys. The red balloons represent observations in the last two weeks of January 2014. EXPLORE THE EBIRD MAP HERE.

This range is by no means static, as marsh habitats with floating and emergent vegetation are often ephemeral and subject to drying out. During abnormally dry years birds may be forced to move, and this could also happen in abnormal cold years. During these movements individuals may go far afield in search of suitable habitat, a behavior that is likely echoed in numerous other species of rails. For winter 2013-2014, we contemplate the source region for this recent vagrancy event and explore hypotheses of what might be driving this year’s movement.

It ain’t the cold in North America!

Cold weather in North America appears to have very little to do with this year’s American Purple Gallinule extravaganza. The polar vortex that has received so much hype in North American media has not directly affected the primary wintering grounds for American Purple Gallinule.

Furthermore, there have been virtually no freezes, prolonged or Departure from Normal Tempisolated, in the species’s typical winter range on the Florida Peninsula. Unlike areas in the Southeast US north of Florida, only 1 day since 4 November 2013 has seen temperatures dip below 0 degrees Celsius in central Florida, with no days below freezing in the heart of their Florida range.

Drought in the Caribbean

The graphic below shows the standardized precipitation indices for the the last 1-, 3-, 6-, and 12-month periods for southeastern Mexico and Central America, the Caribbean, and north South America. Note the striking red colors that become more intense over the course of the last year in the Greater Antilles (especially the Caribbean islands of Hispaniola and Cuba), where American Purple Gallinule winters (and reside year-round) regularly.

Caribbean DeparturesThese colors represent precipitation indices 2 standard deviations below the mean for the past 30 years, indicating significant drought conditions. The potential for these conditions to spawn movements of gallinules seems very high. We believe that the vagrant gallinules probably originated here: this is an area with wintering American Purple Gallinules, the conditions are ideal to spawn a large-scale dispersal event, and as we will see, the wind currents can easily connect vagrant records back to this region.

Wind and air parcel analyses explain vagrant records

PUGA TRAJECTORY 1

Wind patterns this winter have been favourable to support movements of gallinules over the ocean to Iceland and Ireland.  There is a strong Caribbean connection as well, with high altitude winds linking an air parcel beginning on Hispaniola with the North Atlantic. Similar conditions existed on 22 January to support movements of gallinules over the ocean to Iceland and Ireland. Several other maps of air parcels are included in the full BirdCast feature.

Water-cooler Fodder

Although this winter’s cold temperatures could yield far-flung American Purple Gallinules, evidence this year is stronger for drought driving dispersal from the Caribbean and south Florida. The same systems that have brought extreme cold to the eastern U.S. are also bringing these strong wind fields as the storms spin up the east coast, and this surely has aided the successful trans-Atlantic flights by these gallinules. South America does not seem a likely source, given the prevailing flow of winds in potential source areas for gallinules on that continent. But the origin, motivation, and mechanism of movements are open questions and discussions worth continuing, as we have barely scratched the surface of these patterns. For example, conditions are generally favorable this winter for Nearctic and Neotropical vagrants to reach the Palearctic, with general flow of winds to the east across the Atlantic in the presence of an Azores High, a pattern referred to as positive North Atlantic Oscillation (NAO). (As an aside, these conditions and the prevailing trade winds also make for favorable conditions to deposit Palearctic migrants in the Neotropics, a topic we will discuss further in an upcoming BirdCast post.) NAO phases are cyclic, albeit irregular in their timing and strength. Previous years with strongly positive NAO may well correlate with other instances of North Atlantic vagrancy in this species: if anyone looks into that we’d love to hear back! That would help to answer the question of whether this year is different, whether something fundamental changed, or if American Purple Gallinules this year just encountered a perfect combination of drought conditions, positive NAO, and a wobbly polar vortex that is sending numerous strong low pressure systems up the Atlantic Coast. Check out the Full BirdCast Feature.

–AF, MJI, CLW; Team eBird & Team BirdCast