Documents • Iowa State University • Avian Archives of Iowa Online

Title	Genres	Topics	Date (Start)	Date (End)	Type	Description	Creator/Author	Birds	Locations	Locality	Habitat	Remarks

Rare bird documentation form for Thayer's Gull at Cone Marsh, 1983	Field notes	Birds--Identification Ornithology Rare birds	1983-02-27	N/A	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Cone Marsh in Louisa County, IA on February 27, 1983.	Newlon, Michael C.	Thayer's Gull	Cone Marsh Wildlife Management Area	NE side Cone Marsh Louisa Co IA	freshwater marsh with considerable open water	The documentation form by Michael Newlon is the only one submitted and forms the basis of this record. Other observers include Carol S. Newlon. \| Elimination of similar species: proportions, uniformly pale primaries would rule out herring; size/build rules out imm. glaucous. Bill much less heavy than imm. glaucous-winged. Remaining question is whether this bird is (over) a Thayer's Gull or a Kumlien's gull, presently considered separate species but widely suspected of being conspecific. Thayer's is extremely variable, and the limits of its variability are not well known, especially for imm. plumages. [Dwight says of his series of ad. thayeri, 'no two are alike'. It seems probable that there is clinal variation from west to east (thayeri - kumliesi [sic] - nominate glaucoides) and even possible that thayeri interbreeds with argenlatus at the western end of its range.] In addition several plumage descriptions in the literature may be assigned to birds of [illegible] age. Be that as it may: L. glaucoides glaucoides is supposed to have pale warm-brown primaries as a 1-W & paler, nearly whitish areas as a 2-W (though photos in grant's [sic] book show one 2-W with pale-brown primaries concolor with coverts). L. glaucoides kumlieni (in Dwight's plates) is assigned v. pale primaries as a 1-W, with slightly darker outer webs; would look uniform pale grey at any distance. His 2-W has darker primaries, again with slightly darker outer webs [I suspect these assignments should be reversed.] L. thayeri in published description is supposed to have darker primaries still, though not so dark as those of imm. Herring gulls, and lacking contrast with mantle. However some west coast thayeri-type gulls are very pale - though their back color is grey-brown rather than the warmer pale tan of L. glaucoides. (It is possible that these are really kumlieni but little data exists.) It is the similarity of the Cone Marsh Bird to one I photographed in Cal. that convinced me to classify it as thayeri - though kumleni cannot be unequivocally ruled out \| The original documentation form event lasted from 11:10:00/12:30:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Lock and Dam 14, 1995	Field notes	Birds--Identification Ornithology Rare birds	1995-01-03	N/A	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Lock and Dam 14 in Scott County, IA on January 3, 1995.	Kent, Thomas H. (Thomas Hugh), 1934-	Thayer's Gull	Lock and Dam 14	Lock and Dam 14, Scott Co., IA	Mississippi River dam	The documentation form by Thomas H. Kent is the only one submitted and forms the basis of this record. \| Elimination of similar species: I looked at many variable first-winter Herring Gulls today. All had more dark on wing tip and darker tail band. This bird was easy to pick out over and over again. \| The original documentation form event lasted from 12:00:00/12:20:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Red Rock Dam, 1995	Field notes	Birds--Identification Ornithology Rare birds	1995-01-01	1995-03-01	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Red Rock Dam in Marion County, IA on January 1, 1995.	Johnson, Ann	Thayer's Gull	Red Rock Dam	Red Rock Dam, Marion Co., IA	gravel bar below dam	The documentation form by Ann Johnson is the only one submitted and forms the basis of this record. \| Elimination of similar species: Structure, darker mantle, dark eye, and gray primaries eliminate Herring Gull. Other gulls of intermediate size - Lesser Black-backed eliminated by relative gray of mantle, leg color, and primary color. California eliminated by leg color, primary color, and lack of black marking on bill. Iceland eliminated by dark mantle color \| The original documentation form event lasted from 10:15:00/10:30:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Lock and Dam 15, 1995	Field notes	Birds--Identification Ornithology Rare birds	1995-12-17	N/A	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Lock and Dam 15 in Scott County, IA on December 17, 1995.	Petersen, Peter C.	Thayer's Gull	Lock and Dam 15	Lock + Dam 15, seen from Iowa walking near Il. Shore mostly	Open river	The documentation form by Peter C. Petersen is the only one submitted and forms the basis of this record. Other observers include Walter Zuurdeeg, Mary Lou Petersen, and Kelly McKay. \| Elimination of similar species: Herring Gull - heavier bill, very dark primary tips, no windows, tail darker with uneven white edge, secondaries dark from above, underwing much darker. Iceland Gull would show much lighter plumage overall, especially tail + primary tips. \| The original documentation form event lasted from 12:05:00/12:10:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull on the Mississippi River at Davenport, 1996	Field notes	Birds--Identification Ornithology Rare birds	1996-01-07	N/A	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull on the Mississippi River at Davenport in Scott County, IA on January 7, 1996.	Edwards, Chris	Thayer's Gull	Davenport	Mississippi River, Davenport, Scott Co.	River.	The documentation form by Chris Edwards is the only one submitted and forms the basis of this record. Other observers include Curt Nelson. \| Elimination of similar species: Herring Gull has black or dark brown primary tips and secondaries on upperside, dark gray primary tips on underside, whitish head, larger bill. Iceland Gull has white primary tips. \| The original documentation form event lasted from 13:45:00/15:00:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Black Hawk Lake, 1996	Field notes	Birds--Identification Ornithology Rare birds	1996-02-11	1996-02-13	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Black Hawk Lake in Sac County, IA on February 11, 1996.	Thelen, Ed	Thayer's Gull	Black Hawk Lake	Black Hawk Lake Sac County	Natural Lake - near open water from aerator	The documentation form by Ed Thelen is the only one submitted and forms the basis of this record. Other observers include Rob Thelen and Peter Ernzen. \| Elimination of similar species: Herring Gull has dark lesser coverts and dark feathers under the wing tips. More distinct tail band + larger bill. \| The original documentation form event lasted from 09:30:00/10:00:00.	Iowa Ornithologists' Union \| MS 166	34	35
Christmas Bird Count 1996	Field notes	Birds--Identification Ornithology Rare birds	1996-12-22	1996-12-23	Manuscript, graphic, and printed material	Field notes from a Christmas Bird Count with details on the sighting of Thayer's Gull's at Lock and Dam 13, 14, 15 near Davenport and Clinton on December 22 and 23, 1996. Includes observers Pete Petersen, Walter Zuurdeeg and others.	McKay, Kelly	Thayer's Gull Chukar Greater Scaup	Clinton Davenport Lock and Dam 14 Lock and Dam 15 Lock and Dam 13				Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Lock and Dam 15 in Davenport, 1996	Field notes	Birds--Identification Ornithology Rare birds	1996-11-14	N/A	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Lock and Dam 15 in Davenport in Scott County, IA on November 14, 1996.	Fuller, James L	Thayer's Gull	Lock and Dam 15	Lock & Dam #15 of Mississippi River, Davenport (Scott County)		The documentation form by Jim Fuller is the only one submitted and forms the basis of this record. \| Elimination of similar species: The amount of black and white in the outer primary tips (both upper and underwing) is much less than would be expected in Ring-billed or Herring. Ring-billed is smaller with a dark ring on bill of adult. Although a few Herrings have somewhat bright pink legs, most are a dull pink. An Iceland adult should have a lighter mantle and upperwing, and less gray (not black) on the outer primary tips. \| The original documentation form event lasted from 13:50:00/14:15:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Spirit Lake, 1997	Field notes	Birds--Identification Ornithology Rare birds	1997-11-09	N/A	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Spirit Lake in Dickinson County, IA on November 9, 1997.	Schoenewe, Lee A.	Thayer's Gull	Spirit Lake	South Shore of Spirit Lake, Dickinson Co.	Natural lakeshore	The documentation form by Lee A. Schoenewe is the only one submitted and forms the basis of this record. Other observers include Eugene Armstrong, and Eloise Armstrong. \| Elimination of similar species: Herring Gull - Lack of dark color in primaries + tail; Glaucous-size; Iceland - overall gray-brown tinge	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull south of Muscatine, 1997	Field notes	Birds--Identification Ornithology Rare birds	1997-12-28	N/A	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull south of Muscatine in Muscatine County, IA on December 28, 1997.	McKay, Kelly	Thayer's Gull	Muscatine	just south of Muscatine, IA., Muscatine county standing on ice shelves.		The documentation form by Kelly J. McKay is the only one submitted and forms the basis of this record. Other observers include Gerry White. \| Elimination of similar species: The bird was about the size of a herring gull (slightly smaller), but much paler.	Iowa Ornithologists' Union \| MS 166	34	35
Winter Birds 97-98	Field notes	Birds--Identification Ornithology Rare birds	1997-12-01	1998-02-25	Manuscript, graphic, and printed material	List of birds and locations contributed by Aaron Brees. Includes a note to Thomas H. Kent.	Brees, Aaron	Thayer's Gull	Lake Red Rock				Iowa Ornithologists' Union \| MS 166	34	35
Thayer's Gull, 12-20-98, Kelly J. McKay	Field notes	Birds--Identification Rare birds	1998-12-20	N/A	Manuscript, graphic, and printed material	Field notes for the sighting of a Thayer's Gull by Kelly McKay on December 20, 1998.	McKay, Kelly	Thayer's Gull	Iowa				Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Lesser Black-backed Gull at Coralville Reservoir, 1993	Field notes	Birds--Identification Ornithology Rare birds	1993-12-18	1993-12-19	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull at Coralville Reservoir in Johnson County, IA on December 18, 1993.	Bendorf, Carl J.	Lesser Black-backed Gull	Coralville Lake	Coralville Reservoir, Johnson County, Iowa	upper reaches of the Coralville Reservoir	The documentation form by Carl Bendorf is the only one submitted and forms the basis of this record. Other observers include Lanny Haldy, Randy Graesser, Dan Ray, Angela Ray, Kathleen Kuenstling, Randall Pinkston, Thomas Kent, Jim Fuller, and others. \| Elimination of similar species: Of about 500 gulls total, nearly 90% were adult Ring-Billed Gulls and the rest were mostly winter adult and a few subadult Herring Gulls. [...] An adult gull in between the size of adjacent Ring-billed and Herring Gulls. It was noticeable larger than the Ring-bills; not too much smaller than the Herrings. It differed from the Herrings in being a little less barrel chested and a little slimmer, more horizontal in posture. \| The original documentation form event occurred for 45 minutes during two sessions.	Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull in the Cedar River at Cedar Rapids, 1993	Field notes	Birds--Identification Ornithology Rare birds	1993-12-18	1994-01-06	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull in the Cedar River at Cedar Rapids in Linn County, IA on December 18, 1993.	Wickham, Peter P.	Lesser Black-backed Gull	Cedar Rapids	Cedar River, on sandbar across from Cargill plant, Cedar Rapids, IA	Standing, walking around on sandbar	The documentation form by Peter Wickham is the only one submitted and forms the basis of this record. \| Elimination of similar species: The dark mantle, yet whitish head, neck, and underparts identified it as an adult gull, and immediately eliminated Herring, Ring-billed and other gray or whitish-backed gulls. It was too small for Great Black-backed Gull, which has flesh-colored legs anyway, or Slaty-backed Gull, which has pinkish legs. The mantle wasn't truly black, as a Great Black-backed mantle would be. \| The original documentation form event lasted from 14:15:00/14:25:00.	Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull at Greencastle Road at Coralville Reservoir, 1993	Field notes	Birds--Identification Ornithology Rare birds	1993-12-19	N/A	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull at Greencastle Road at Coralville Reservoir in Johnson County, IA on December 19, 1993.	Fuller, James L	Lesser Black-backed Gull	Coralville Lake	East of the north end of the Greencastle Road at the Coralville Reservoir (Johnson County).	Shallow water and mudflats.	The documentation form by Jim Fuller is the only one submitted and forms the basis of this record. Other observers include John McClure, Chris Edwards, and Jonnie Ellsworth. \| Elimination of similar species: All other dark mantled gulls have a larger size. They also have pink legs, with the exception of Yellow-footed Gull, which has never been known to wander from Baja and Southern California. Yellow-footed gull is also considerably larger. No one disagreed with identification. \| The original documentation form event lasted from 12:55:00/13:15:00.	Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull on the Mississippi River between Bettendorf, IA and Moline, IL, 1992	Field notes	Birds--Identification Ornithology Rare birds	1992-02-02	N/A	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull on the Mississippi River between Bettendorf in Scott County, IA and Moline in Rock Island County, IL on February 2, 1992.	Petersen, Peter C.	Lesser Black-backed Gull	Bettendorf Moline	Miss. River between Bettendorf, Scott Co., IA + Moline, R.I. Co., IL.	Main channel of Miss. River	The documentation form by Peter C. Petersen is the only one submitted and forms the basis of this record. Other observers include Ann Johnson and Gerald White. \| Elimination of similar species: Great-Black-backed- seen with one, much smaller, mantle not black. Slaty-backed. This bird smaller than Herrings, legs were yellow. \| The original documentation form event lasted from 13:30:00/13:35:00.	Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull at Mississippi River between Bettendorf, IA and Moline, IL, 1992	Field notes	Birds--Identification Ornithology Rare birds	1992-01-31	1992-02-07	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull at Mississippi River between Bettendorf in Scott County, IA and Moline in Rock Island County, IL on January 31, 1992 and February 1, 1992.	Fuller, James L	Lesser Black-backed Gull	Bettendorf Moline	Mississippi River between Moline, Illinois and Bettendorf, Iowa.		The documentation form by Jim Fuller is the only one submitted and forms the basis of this record. Other observers include Charles Fuller and Jane Fuller. \| Elimination of similar species: The only other dark mantled gull with yellow legs is Yellow-footed Gull, which has never been seen outside of the extreme southwestern part of the country. Yellow-footed gull is also larger than the Herring gull, but this bird was smaller in general size. \| The original documentation form event lasted from 14:35:00/14:45:00 on January 31, 1992 and 09:50:00/10:00:00 on February 1, 1992.	Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull at Lock and Dam 15, 1992	Field notes	Birds--Identification Ornithology Rare birds	1992-01-17	N/A	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull at Lock and Dam 15 in Davenport in Scott County, IA on January 17, 1992.	Kent, Thomas H. (Thomas Hugh), 1934-	Lesser Black-backed Gull	Lock and Dam 15	Above Lock + Dam 15, Davenport, IA	Frozen river	The documentation form by Thomas H. Kent is the only one submitted and forms the basis of this record. Other observers include Jim Fuller. \| Elimination of similar species: Size and leg color eliminate other dark mantled gulls. \| The original documentation form event lasted from 13:30:00/14:30:00.	Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull at Mississippi River between Bettendorf, IA and Moline, IL, 1992	Field notes	Birds--Identification Ornithology Rare birds	1992-01-11	N/A	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull at Mississippi River between Bettendorf in Scott County, IA and Moline in Rock Island County, IL on January 11, 1992.	Petersen, Peter C.	Lesser Black-backed Gull	Bettendorf Moline	Miss. R. between Bettendorf + Moline, Scott + R.I. Cos.	river channel	The documentation form by Peter C. Petersen is the only one submitted and forms the basis of this record. \| Elimination of similar species: Great Black-backed - back not black, too small. Slaty-backed - a bit small, trailing edge of wing with narrow, not wide, white edge. Western - a bit small bill not larger + heavier than the several nearby Herrings. \| The original documentation form event lasted from 08:50:00/09:00:00.	Iowa Ornithologists' Union \| MS 166	34	36
Details for rare bird sighting, Jim Fuller, 1992	Field notes	Birds--Identification Ornithology Rare birds	1992-01-05	N/A	Manuscript, graphic, and printed material	Field report for sighting of a Lesser Black-backed Gull at Lock and Dam 14 and at Moline Riverfront on January 5, 1992, contributed by Jim Fuller. Other observers include Jane Fuller and Carol Thompson.	Fuller, James L	Lesser Black-backed Gull	Lock and Dam 14 Moline				Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull at Cedar Lake, 1992	Field notes	Birds--Identification Ornithology Rare birds	1992-01-05	N/A	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull at Cedar Lake in Linn County, IA on January 5, 1992.	Kent, Thomas H. (Thomas Hugh), 1934-	Lesser Black-backed Gull	Cedar Lake	Cedar Lake, Linn Co., Iowa	backwater lake and cooling pond with some ice	The documentation form by Thomas H. Kent is the only one submitted and forms the basis of this record. \| Elimination of similar species: The leg color and size eliminate other dark mantled gulls. \| The original documentation form event lasted from 09:50:00/10:00:00 and 10:30:00.	Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull at Saylorville Reservoir, 1986	Field notes	Birds--Identification Ornithology Rare birds	1986-11-29	N/A	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull at Saylorville Reservoir in Polk County, IA on November 29, 1986.	Dinsmore, Stephen J.	Lesser Black-backed Gull	Saylorville Lake	Saylorville Reservoir, Polk Co.	sitting on ice above dam	The documentation form by Steve Dinsmore is the only one submitted and forms the basis of this record. Other observers include Peter Wickham, Mark Brogie, Barb Wilson, Tanya Bray, and Bery Engebretsen. \| Elimination of similar species: Great Black-backed Gull was eliminated by the smaller size, contrast between the wingtips and the rest of the wing, and by the heavy streaking on the head (head should be mostly white on a Great Black-backed Gull). California Gull was eliminated by the darker mantle, darker underwing and dark carpal bar, lack of a dark spot on the bill, and by the dark smudge at the base of the bill (this is characteristic of 3rd summer Lesser Black-backed Gulls and is never present on California Gulls). \| The original documentation form event lasted from 10:08:00/12:10:00.	Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull at Lock and Dam 15, 1995	Field notes	Birds--Identification Ornithology Rare birds	1995-02-05	1995-02-21	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull at Lock and Dam 15 in Scott County, IA on February 5, 1995 and February 12, 1995.	Fuller, James L	Lesser Black-backed Gull	Lock and Dam 15	Mississippi River above Lock & Dam #15 (Scott County)		The documentation form by James Fuller is the only one submitted and forms the basis of this record. Other observers include Jim Scheib, Thomas Kent, Dan Dorrance, Barker, Peter C. Petersen, Eloise Armstrong, and Eugene Armstrong. \| Elimination of similar species: The only other dark mantled gull with yellow legs is the Yellow-footed Gull. That bird has never been seen away from the extreme southwest portion of the country, and it should be much larger. \| The original documentation form event lasted from 08:30:00/09:00:00 on February 5, 1995 and 11:40:00/11:55:00 on February 12, 1995.	Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull at Lock and Dam 15, 1995	Field notes	Birds--Identification Ornithology Rare birds	1995-02-04	N/A	Rare birds documentation form	Rare bird documentation form for a Lesser Black-backed Gull at Lock and Dam 15 in Scott County, IA on February 4, 1995.	Kent, Thomas H. (Thomas Hugh), 1934-	Lesser Black-backed Gull	Lock and Dam 15	Above Lock and Dam 15, Davenport, Scott Co., IA	Mississippi River, river open.	The documentation form by Thomas H. Kent is the only one submitted and forms the basis of this record. Other observers include several unnamed people. \| Elimination of similar species: The size and mantle color exclude Great Black-backed Gull. The mantle was too dark for a California Gull. Slaty-backed Gull would likely appear larger, have a darker mantle, and more white in tertials. \| The original documentation form event lasted from 12:30:00/13:00:00 estimated.	Iowa Ornithologists' Union \| MS 166	34	36
Rare bird documentation form for Lesser Black-backed Gull at Lindsay Park Harbor in 1995	Field notes	Birds--Identification Ornithology Rare birds	1995-02-03	1995-02-16	Manuscript, graphic, and printed material	Rare bird documentation form for a Lesser Black-backed Gull at Lindsay Park Harbor in Scott County, IA on February 3 and 16, 1995.	Petersen, Peter C.	Lesser Black-backed Gull	Lindsay Park				Iowa Ornithologists' Union \| MS 166	34	36