The Peregrine Vol 18, No 1, January/February 2019
Additional Article
Interview with Lowell Burket

Burket's Warbler
Burket's Warbler
(All photos by Lowell Burket)

How a Pittsburgh Birder's Sharp Eye and Ear
Made History with a Hybrid of Three Species
by Tom Moeller

Lowell Burket was given a gift in May 2018 in the form of a bird which did not fit into all the things he had learned about warblers. This warbler seemed to be like a Brewster's warbler (a hybrid of a Golden-winged and a Blue-winged Warbler), but his observations and photos showed something else. Several characteristics of the Brewster's were missing and coloration was different, including faint reddish spots on the bird's breast.

Was this a new backcross, a mutation, or something else?

Lowell has enjoyed visiting his grandparents', later parents' farm in Blair County since he was a toddler. Today, as an attorney in Pittsburgh, he loves to walk, bike-ride, hunt, and explore the property as a respite from the stress of work. Until his father's death in 2011, Lowell's family had horses to ride around the area. After his death, the family decided it was best to sell the horses. Now on his feet or a bike, Lowell could carry a camera when on the property. He took photos of deer, raccoons, coyotes and other animals he encountered. There is a pond on the property, but Lowell found a small, natural basin of water where birds came to drink, which he named the 'birdhole.'


He liked photographing the colorful birds that gathered there, but his first images made the birds seem like little dots of color. As with all photographers, bigger cameras and bigger lenses were needed. However, he was not familiar with the names of the birds. So Lowell asked his father-in-law, Larry Stump, a long-time birder, what he had captured in his camera. When told he had a Tufted Titmouse, Lowell was greatly amused at the name.

Over five years, Lowell developed his photography and knowledge of the birds, especially the colorful warblers that visited the birdhole and other parts of his property. He has been able to get photos of 34 species of warblers there. Through constant exploration he knows where on the property to find a certain warbler during the season.
Burket's Warbler
Mystery Warbler

On May 7, Lowell photographed his mystery warbler. Checking his photos later, he thought it might be a Brewster's, but the plumage was wrong. There was no eye-line and the breast was white instead of yellow. Then there were those red dots! At first he thought it might be dirt or blood on one side of the bird, but a face-on photo showed symmetrical spots on both sides of the bird's breast. Is it a mutation? Lowell's wife Anne said there were too many variances for the bird to be a mutation. One or two maybe, but not six. The couple mulled over this problem as Lowell had to return to work, asking Lowell's brother Brian to get as many videos of the bird as he could while Lowell was in court in Pittsburgh.
Burket's Warbler in Song
Burket's Warbler in Song

The clincher came on May 25, when Lowell was back and looking for the bird. A deer came by, so Lowell began to video tape the animal, not hearing in the background a Chestnut-sided Warbler's song, which was recorded on the deer video. When Lowell stopped recording, he looked up at the singing bird which was NOT a Chestnut-sided Warbler but the odd Brewster's he was seeking! The red dots then made sense. This bird was part Chestnut-sided Warbler! It was a male hybrid singing on territory the song it had learned from its father.

This male probably hatched last summer (2017) on or near the family property in Blair County. Lowell has photos of a female Brewster's Warbler on his property on June 30, 2017 — perhaps the mother of this new hybrid.
Brewster's Warbler
Brewster's Warbler - June 30, 2017

Now the question was who to tell about this warbler. Lowell thought about this decision long and hard. He decided to write to Dr. Irby J. Lovette, Director of the Fuller Evolutionary Biology Program at the Cornell Lab of Ornithology. Lowell presented his "warbler creds" with all his photos and listings on eBird as background to show his reporting was not frivolous. Writing carefully, Lowell presented his case for the bird being a cross between a Brewster's and a Chestnut-sided Warbler, and backing it up with his photos and a video of the bird singing the Chestnut-sided Warbler song. Unfortunately, Dr. Lovette was in Alaska for another month, and he would get back to Lowell when he returned.

Wondering whether the bird would still be around, Lowell tried to contact someone else at the Cornell Lab. He was emailed by Dr. David Toews, who said he would come down to see the bird.
Burket's Warbler
Captured Burket's Warbler
Late in June Dave made the four-hour drive down from Cornell to Blair County. The next morning, June 26, 2018, Lowell's mother Gwen made sandwiches and packed food and drinks for the group's all-day attempt to catch the hybrid. Lowell and Brian helped Dave set up mist nets around the 'birdhole,' and they began playing the call Lowell had recorded on a video of the bird. Almost immediately the bird appeared overhead, flying from tree to tree above the mist nets. It was looking for the male daring to sing in his territory. Dave then switched to the fledgling call of a Chestnut-sided Warbler. The target bird then zig-zagged down and was caught in the net. The 'all-day attempt' turned into a four-minute success!
DNA Strands
Mitochondrial DNA Strands

The captors were all smiles. The bird was banded with a single aluminum band, no colored ones. Dave took a blood sample for testing the bird's heritage. He told Lowell it might take two or three weeks to test the mitochondrial DNA of the sample to determine its origin. (Mitochondrial DNA is only passed from the mother to her offspring.) Still smiling, Dave made the four-hour trip back to Cornell. Two days later Dave texted Lowell, "You were right!" The blood sample proved that the hybrid had a Brewster's Warbler mother and later a Chestnut-sided Warbler father. (Lowell believes Dave just worked straight through without sleep to get the first results so fast.)
Burket's Warbler
Burket's Warbler with New Band on Leg
Lowell was able to see and photograph the hybrid a few more times during the summer, but he was now under constraints NOT to reveal details to anyone until the final report on the tests were published. At last on November 7, 2018, Dave Toews's paper, "A wood-warbler produced through both interspecific and intergeneric hybridization," (by David P. L. Toews, Henry M. Streby, Lowell Burket, Scott A. Taylor) was published and things started popping for Lowell, for Dave, and for the entire birding community.

Lowell never called out to any news outlet, publisher, or other media — they all contacted him. The story of a brand new bird went national and international. In a little over two weeks the story had hit 255 websites, been highlighted on radio and television, and reported in 40 countries of the world. The impact of his new fame has not really hit Lowell yet. He is just happy that his story will appear in Cornell Lab's magazine Living Bird along with his name. He was interviewed on CBC Radio's "As It Happens" program, his story appeared in the November 17, 2018 digital edition of the Pittsburgh Post-Gazette, the Three Rivers Birding Club honored him with a complimentary membership, and he sat down for his first face-to-face interview for this article. Questions and interview requests are still coming in.

The hybrid, now unofficially called the Burket's Warbler, has already experienced one migration south during the winter after it hatched. It was last seen by Lowell in August, and it is probably in a much warmer southern area now. Birders are in fact out looking for the banded bird in areas where Chestnut-sided Warblers and Brewster's are known to overwinter, Central America, the Caribbean islands, or even northern South America.
Graphic - JDitner
(To see an enlargement of this graphic, right click it and choose "View Image" from the menu.)

This is truly an inspiring story for all birders. Like Lowell Burket, you can be in the right place and have the right skills — not necessarily learned in a classroom — to make a significant contribution to our knowledge of birds, whether a new species, a new location to find a bird, a new behavior you witness, a sighting of a banded bird, or even participation on a Christmas bird count. We can all contribute in our own way!

Image Gallery

Mission of 3RBC

To gather in friendship, to enjoy the wonders of nature and to share our passion for birds!

© Photo Credits:
Sherron Lynch, Brian Shema, Chuck Tague