Category Archives: Rare Birds

Posts about rare birds

Concepts – Relative vs. Absolute Rarities

Brant

A relatively rare but still exciting Brant at Montrose Point in Chicago, January 2021. (click to see the larger version)

Birders think a lot about rare birds. More than think about — we obsess over them, drive thousands of miles to chase them, and dream about finding them. But what is a rarity? There are a couple of ways to think about this. Most of the rare birds we see are only regionally unusual, that is, they are common someplace within their range but uncommon outside it. The Brant that showed up at Montrose in early January is a good example of this concept. The world population is in the hundreds of thousands, and they’re common on their wintering grounds from New Jersey to Massachusets on the East Coast. Illinois is outside of their main range and migration route, so it’s a big deal here; when one shows up it generates a lot of excitement in the birding community. Brant is rare enough in Illinois to be on the review list of birds requiring documentation, and Montrose has four or so previous records. Relative rareness doesn’t just include birds outside their normal range, it also includes birds outside of their normal timeframe. A Bay-breasted Warbler in Chicago in December is an example.

The other kind of rarity are birds whose entire population is low. The world population of Kirtland’s Warbler in 2020, for example, was a little under 5,000 birds. That’s not a lot. By comparison, the seating capacity of the bleachers at Wrigley Field is about 5,000. Such small populations are vulnerable to all sorts of disturbances. This class has a handful of species, most of which are on the Endangered Species List. Of these, a few have been recorded in Illinois, including Kirtland’s Warbler, and recent records of Whooping Crane and Red-cockaded Woodpecker.

Brant, January 5, 2020

Brant

Brant (click to see the larger version)

By far the most exciting bird of this early winter rarity season is the adult Brant that showed up on January 4. The bird has been associating with Canada Geese at the harbor, and that’s where I saw it on January 5. This is likely the same Brant that was seen along the Wisconsin Lake Michigan lakefront last fall. Brant are rare as far west as the western Great Lakes, as witnessed by the number of previous records for Montrose. It’s also rare enough in Illinois to be on the review list of birds requiring documentation. If you want to see this bird, check the flocks of Canada Geese that frequent the harbor. More photos of the Brant are at my eBird checklist for the morning, URL below.

Addendum: The Brant was last reported on January 25.

Previous Montrose Brant Records

  • October 15, 1947
  • December 2-4, 1990
  • September 27, 2001
  • October 29, 2008

eBird Checklist
January 5, 2021

MEGA! Cassin’s Sparrow, November 13, 2020

Cassin's Sparrow

Cassin’s Sparrow. Photo by Geoff Williamson. (click to see the larger version)

November is one of the most exciting months for birders. We look forward to it with the same sense of anticipation and excitement as we do for May, and with good reason. The annals of Illinois ornithology are filled with November rarities and vagrants.

On the morning of November 13 I was walking the outside of the boat storage lot at Montrose as I have been since a Harris’s Sparrow showed up there in October. I never birded it much in the past and usually just walked by it on my way to the rest of the Point. I didn’t see the October Harris’s Sparrow but I was finding other sparrows, so I had enough incentive to keep checking. At about 8:30 a.m. I kicked up a small bird near a spruce tree on the northeast side of the lot. I thought at first it was a wren but the thick bill ruled out a wren and ruled in a sparrow. The bird was plain to the point of being non-descript and had a long tail. Several possibilities came to mind. I suspected Cassin’s Sparrow based on probability, and when I saw the flank streaking I knew that’s what it was. The bird was decidedly uncooperative for me and played a frustrating game of hide and seek that made seeing plumage details almost impossible. Others had better luck viewing it after I left. Close-up photos show diagnostic field marks for this species that weren’t apparent in the field, including white tips to the outer tail feathers and horizontal barring on the tail. This is the first Cassin’s Sparrow for Montrose, number 347.

Cassin’s Sparrow is a bird of the American Southwest, but they do wander and occur far out of their normal range. eBird has records for the East Coast, New England, and the Canadian Maritimes. Illinois has three previous records, all within the last 40 years. It is a species if not to be expected than to at least consider seriously as a possibility.

To see a list of the birds that have been recorded at Montrose, refer to the Birds Recorded at Montrose Point in Chicago page.

Previous Illinois Cassin’s Sparrow Records

  • May 27 – June 6, 1983, Chicago, Cook County
  • May 3 – 6, 2011, Winthrop Harbor, Lake County
  • September 8, 2014, Chicago, Cook County

Brewer’s Blackbird, October 10, 2020

Brewer's Blackbird

Brewer’s Blackbird (click to see the larger version)

It’s hard to believe Brewer’s Blackbird is rare anywhere in Illinois but they are at Montrose Point in Chicago. They nest to the north of us in Illinois, Wisconsin, and Michigan, but for whatever reason, they largely avoid the Chicago lakefront. So seeing one at Montrose on October 10 was exciting. The bird, a female, was in the Dunes for a few minutes before flying south and disappearing. More photos of the Brewer’s are at my eBird checklist for the morning, URL below.

eBird Checklist
October 10, 2020

Purple Gallinule (!), September 23, 2020

Purple Gallinule

Purple Gallinule (click to see the larger version)

Fortuitous – Happening by a lucky chance; fortunate.

On the morning of September 23 I was walking on the footpath at the east end of Montrose Point as I usually do when I visit. This is one of my favorite places at Montrose as it provides a sweeping view of Chicago and Lake Michigan. Around 7:30 an unfamiliar, medium-sized bird flew over me, heading west, and moving fast. Right behind it and in hot pursuit was one of our local Peregrine Falcons. I thought the mystery bird may have been a Least Bittern or Green Heron. Whatever it was it just missed becoming breakfast for the Peregrine and crash-landed in some shrubs not far from where I was walking. I hurried over to where I thought the bird came down and after poking around found a juvenile Purple Gallinule about 10 feet up buried in dense vegetation. It appeared stunned from the near-death experience and didn’t move while I watched and photographed it. The bird stayed in the same spot for the rest of the day and was viewed and photographed by many. It was not seen after September 23. This is the second record of Purple Gallinule for Montrose. I’ve included a link to my eBird checklist for the day below.

Purple Gallinules breed in the southeastern United States, parts of Mexico and Central America, the Caribbean, and throughout much of South America. Birds in the southeastern United States are migratory and retreat to the American tropics and Florida for the winter. Assuming the bird was born in the US, the Montrose Purple Gallinule should have gone south instead of north, an example of mirror image misorientation. Purple Gallinule vagrancy is well-established; individuals occur regularly far out of range in North America.

Previous Purple Gallinule Records For Montrose Point
May 7 – 10, 1999 (adult). Meadowlark, A Journal of Illinois Birds, Volume 8, Number 4.

eBird Checklist
September 23, 2020