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 Red Rock Reservoir, 1993	Field notes	Birds--Identification Ornithology Rare birds	1993-11-13	1993-11-16	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Red Rock Reservoir in Marion County, IA on November 13, 1993.	Cecil, Robert I.	Thayer's Gull	Lake Red Rock	Tailwaters, Red Rock Res.	Tailwaters/River	The documentation form by Bob Cecil is the only one submitted and forms the basis of this record. Other observers include Tom Kent and Dick Tetrault. \| Elimination of similar species: 1st winter Herring Gull has a very dark secondary bar, often has lighter head, and generally has a much more 'contrastry' appearance involving darker and lighter shades of brown. Overall, the 1st winter Herring is darker brown. \| The original documentation form event occurred in the afternoon.	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 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 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
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 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 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 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 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 Red Rock Dam, 1993	Field notes	Birds--Identification Ornithology Rare birds	1993-12-24	N/A	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Red Rock Dam in Marion County, IA on December 24, 1993.	Johnson, Ann	Thayer's Gull	Red Rock Dam	Below Red Rock Dam, Marion County, Iowa	Open river with gravel bars	The documentation form by Ann Johnson is the only one submitted and forms the basis of this record. Other observers include Raymond Cummins. \| Elimination of similar species: Dark eye and head/bill structure eliminated Herring Gull. \| The original documentation form event lasted from 11:20:00/11:30:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Redrock Dam, 1993	Field notes	Birds--Identification Ornithology Rare birds	1993-12-24	1994-01-14	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Redrock Dam in Marion County, IA on December 24, 1993.	Cummins, Raymond L.	Thayer's Gull	Red Rock Dam	Lake Redrock below dam, Marion Co.	Open water below spillway.	The documentation form by Ray Cummins is the only one submitted and forms the basis of this record. Other observers include Ann Johnson. \| Elimination of similar species: see above. [...] I picked this bird out because of it's small size compared to the other Herring Gulls present (40). It was smaller than any of the Herring gulls present, but still much larger than any of the numerous Ring-billed gulls. The head appeared more rounded than the Herring gulls and the heavy brown streaking on the nape and neck was more extensive and darker than any Herring present. The bill w/a red gonys mark on the lower mandible was shorter and thinner w/less gonys than the Herrings. They eye iris was dark not yellowish as in all the Herrings present. \| The original documentation form event lasted from 10:00:00/10:35:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull southeast of Jolly Roger Marina 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 Thayer's Gull southeast of Jolly Roger Marina at Coralville Reservoir in Johnson County, IA on December 19, 1993.	Pinkston, Randall, 1956-	Thayer's Gull	Jolly Rogers Campground	Coralville Reservoir (1/4 - 1/2 mile southeast of Jolly Roger Marina), Johnson County, Iowa		The documentation form by Randall Pinkston is the only one submitted and forms the basis of this record. \| Elimination of similar species: Contrasted with first-winter Herring Gull above. First-winter Iceland typically much paler, especially the uppersurface of the primaries which are paler than the rest of the mantle, and Iceland should show mottling in the tertials and tail band. I suppose I cannot exclude a heavily-pigmented 'Kumlien's' Gull or an Iceland-Thayer's intergrade as described in Kevin Zimmer's Birding article. Both species are apparently highly variable. \| The original documentation form event lasted from 10:45:00/11:15:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Red Rock Dam, 1993	Field notes	Birds--Identification Ornithology Rare birds	1993-11-13	N/A	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Red Rock Dam in Marion County, IA on November 13, 1993.	Pinkston, Randall, 1956-	Thayer's Gull	Red Rock Dam	Lake Red Rock dam, Marion County, Iowa		The documentation form by Randall Pinkston is the only one submitted and forms the basis of this record. Other observers include Jim Fuller. \| Elimination of similar species: Compared with first-winter Herring Gull above. Pale Thayer's may be confused with same-aged Iceland Gull, but Iceland typically much paler than this individual. Iceland should also show pale, mottled tertials and tail which are concolor with the upperparts. This bird's tertials and tail were unpatterned (except at the edges of the tertials) and darker than the remainder of the upperparts. Iceland's folded primaries are paler than the remainder of the mantle, not darker as in this bird. Slaty-backed, Glaucous-winged, and Glaucous-winged X Western hybrid Gulls all larger, have more massive bills, less likely in Iowa. \| The original documentation form event lasted from 10:15:00/10:40:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Franklin's Gull at Saylorville Reservoir, 1987	Field notes	Birds--Identification Ornithology Rare birds	1987-12-02	1987-12-04	Rare birds documentation form	Rare bird documentation form for two Franklin's Gulls at Saylorville Reservoir in Polk County, IA on December 2, 1987.	Dinsmore, Stephen J.	Franklin's Gull	Saylorville Lake	Saylorville Reservoir, Polk Co.-above dam	resting with other gulls on large reservoir	The documentation form by Steve Dinsmore is the only one submitted and forms the basis of this record. \| Elimination of similar species: The dark hood and wing pattern eliminate all other gulls except Laughing Gull. The small bill and white bar separating the black wingtip from the rest of the wing eliminates Laughing Gull (in adult plumage). \| The original documentation form event lasted from 15:40:00/16:30:00.	Iowa Ornithologists' Union \| MS 166	34	32
Rare bird documentation form for Thayer's Gull at Iowa City, 1993	Field notes	Birds--Identification Ornithology Rare birds	1993-01-19	N/A	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Iowa City in Johnson County, IA on January 19, 1993.	Kent, Thomas H. (Thomas Hugh), 1934-	Thayer's Gull	Iowa City	Iowa City, Johnson Co., Iowa.	partially open Iowa 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: I distinguished this bird from Herring Gull based on smaller body size, smaller head and bill, shorter wing span, uniform light tan coloration, medium brown (not black) outer primaries, translucent primaries from below, and medium brown tail band. I distinguished it from Iceland Gull by the brown outer primaries, relatively more tan coloration, and medium brown tail band. \| The original documentation form event lasted from 11:40:00/11:50:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Lock and Dam 15 in Davenport, 1992	Field notes	Birds--Identification Ornithology Rare birds	1992-01-17	1992-01-19	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 January 17, 1992.	Cecil, Robert I.	Thayer's Gull	Lock and Dam 15	Lock and Dam 15, Davenport, Iowa. Rusty Pelican Restaurant	River	The documentation form by Bob Cecil is the only one submitted and forms the basis of this record. \| Elimination of similar species: See above discussion. [...] The wingtip pattern is what caught my attention. There was much less darkening to the outer primaries than on accompanying gulls. [...] When viewed fro [sic] underneath, the wingtips of the subject bird were white to the tips, with the exception of very narrow black tips at the tips of the primaries. This was very different from the adult Herring/Ring-bills which had substantial black towards the end of the underwings. \| The original documentation form event lasted from 10:30:00/10:45:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Lock + 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 Thayer's Gull at Lock and Dam 15 in Davenport in Scott County, IA on January 17, 1992.	Kent, Thomas H. (Thomas Hugh), 1934-	Thayer's Gull	Lock and Dam 15	Lock + Dam #15, Davenport, IA	Mississippi 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 and others. \| Elimination of similar species: Herring Gull-see above. \| The original documentation form event lasted from 15:30:00/15:35:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Lock and Dam 19, 1990	Field notes	Birds--Identification Ornithology Rare birds	1990-11-06	1990-11-09	Rare birds documentation form	Rare bird documentation form for a Thayer's Gull at Lock and Dam 19 in Keokuk in Lee County, IA on November 6, 1990.	Cecil, Robert I.	Thayer's Gull	Lock Number 19	Behind Lock and Dam 19 at Keokuk, Lee County, Iowa	River	The documentation form by Robert Cecil is the only one submitted and forms the basis of this record. \| Elimination of similar species: Too small, to [sic] uniform in color for Herring. Slight darkening at wingtips eliminates Iceland. \| The original documentation form event lasted from 07:45:00/08:00:00 and 13:30:00/13:40:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Thayer's Gull at Island View at Rathbun Reservoir, 1986	Field notes	Birds--Identification Ornithology Rare birds	1986-12-20	1986-12-23	Rare birds documentation form	Rare bird documentation form for three Thayer's Gulls at Island View Park at Rathbun Reservoir in Appanoose County, IA on December 20, 1986.	Dinsmore, Stephen J.	Thayer's Gull	Island View Park	Rathbun Reservoir, Appanoose Co. (Island View East and West Areas)	sitting on ice and feeding on open water with other gulls	The documentation form by Stephen J. Dinsmore is the only one submitted and forms the basis of this record. Other observers include Ray Cummins. \| Elimination of similar species: The first-year birds were separated from first-year Iceland Gull by the distinct tail band and the darker primaries and from first-year Herring Gull by head shape, bill size, more uniform body color, and the silvery-white underwing. The adult bird was separated from an adult Iceland Gull by size, bill shape, and more black (still not too much, though) in the wingtips and from an adult Herring Gull by head shape, bill size, and paler wingtips. \| The original documentation form event lasted from 10:05:00/10:30:00 and 13:30:00/13:54:00.	Iowa Ornithologists' Union \| MS 166	34	35
Rare bird documentation form for Herring Gull at Red Rock Reservoir, 1991	Field notes	Birds--Identification Ornithology Rare birds	1991-01-04	1991-01-23	Rare birds documentation form	Rare bird documentation form for a Herring Gull at Red Rock Reservoir in Marion County, IA on January 4, 1991.	Kent, Thomas H. (Thomas Hugh), 1934-	Herring Gull	Lake Red Rock	Red Rock Reservoir, Marion County, Iowa	Des Moines River below dam, water mostly open with ice on edges	The documentation form by Thomas H. Kent is the only one submitted and forms the basis of this record. Other observers include Jim Fuller and Tim Barksdale. \| Elimination of similar species: The color of the back and obvious window in the inner primaries, as well as the rest of the feather tracts, all fit 2nd winter Herring Gull and seem to exclude Lesser Black-backed Gull. The soft parts were somewhat atypical, but I was not bothered much by this because I have seen much variation in Herring Gulls. \| The original documentation form event lasted from 08:10:00/08:25:00 and 12:45:00/13:00:00 (approximate)	Iowa Ornithologists' Union \| MS 166	34	34
Rare bird documentation form for Herring Gull at MidAmerican Energy Ponds near Council Bluffs, 1985	Field notes	Birds--Identification Ornithology Rare birds	1985-05-24	1985-06-03	Rare birds documentation form	Rare bird documentation form for a Herring Gull at MidAmerican Energy Ponds near Council Bluffs in Pottawattamie County, IA on May 24, 1985.	Wilson, Barbara L.	Herring Gull	MidAmerican Energy Ponds	IPL Settling Ponds, Council Bluffs, Iowa		The documentation form by Barb L. Wilson is the only one submitted and forms the basis of this record. \| Elimination of similar species: Similar to most of the other large immature gulls of the world. Mantle too light for Black-backed group. Wingtips, even in their folded condition, too dark for Glaucous, Glaucous-winged, etc. that leaves a whole mess of light-mouthed large gulls with dark wing tips. Description seems to match young Herring Gull (second summer ?) well enough. Eye color would probably be becoming pale in a Herring of this plumage, but perhaps not, + it might not show at the distance. I have trouble eliminating California Gull, but it is even harder to support that species.	Iowa Ornithologists' Union \| MS 166	34	34
Rare bird documentation form for Bonaparte's Gull at the Mississippi River at Keokuk, 1987	Field notes	Birds--Identification Ornithology Rare birds	1987-12-31	1988-01-14	Rare birds documentation form	Rare bird documentation form for a Bonaparte's Gull at the Mississippi River at Keokuk in Lee County, IA on December 31, 1987.	Cecil, Robert I.	Bonaparte's Gull	Keokuk	Miss. River at Keokuk, Lee County, Iowa	Lock and Dam 19 Tailwaters	The documentation form by Robert Cecil is the only one submitted and forms the basis of this record. \| Elimination of similar species: Common Black-headed has dark underwings. I would have noticed this. \| The original documentation form event lasted from 14:05:00/14:10:00.	Iowa Ornithologists' Union \| MS 166	34	33
Rare bird documentation form for Franklin's Gull at Saylorville Reservoir, 1991	Field notes	Birds--Identification Ornithology Rare birds	1991-02-01	N/A	Rare birds documentation form	Rare bird documentation form for a Franklin's Gull at Saylorville Reservoir in Polk County, IA on February 1, 1991.	Dinsmore, Stephen J.	Franklin's Gull	Saylorville Lake	Saylorville Reservoir, Polk Co.-at spillway below dam		The documentation form by Stephen J. Dinsmore is the only one submitted and forms the basis of this record. \| Elimination of similar species: The dark gray wings separated from the black wingtip by a white bar, broad white eye crescents, stocky bill lacking a pronounced gonys and rounder wings eliminate Laughing Gull. The combination of the black head and dark gray mantle eliminates other dark-headed gulls such as Bonaparte's and Common Black-headed gulls. \| The original documentation form event lasted from 16:10:00/17:20:00.	Iowa Ornithologists' Union \| MS 166	34	32
Rare bird documentation form for Franklin's Gull at Jolly Rogers Campground at Coralville Reservoir, 1990	Field notes	Birds--Identification Ornithology Rare birds	1990-12-16	1990-12-18	Rare birds documentation form	Rare bird documentation form for a Franklin's Gull at Jolly Rogers Campground at Coralville Reservoir in Johnson County, IA on December 16, 1990.	Kent, Thomas H. (Thomas Hugh), 1934-	Franklin's Gull	Jolly Rogers Campground	Coralville Reservoir (Jolly Roger), Johnson Co., IA	wide part of reservoir	The documentation form by Thomas H. Kent is the only one submitted and forms the basis of this record. Other observers include Carl Bendorf, Carol Thompson, and others. \| Elimination of similar species: Bonaparte's [handwritten note - 'neither is Franklins!] not hooded at this time of year and has lighter wing with white leading edge. In the last several years, Franklin's Gulls in alternate plumage have been recorded in the midwest in winter. \| The original documentation form event lasted from 13:30:00/13:45:00 estimate.	Iowa Ornithologists' Union \| MS 166	34	32
Rare bird documentation form for Franklin's Gull at Coralville Reservoir, 1990	Field notes	Birds--Identification Ornithology Rare birds	1990-12-16	N/A	Rare birds documentation form	Rare bird documentation form for a Franklin's Gull at Coralville Reservoir in Johnson County, IA on December 16, 1990.	Bendorf, Carl J.	Franklin's Gull	Coralville Lake	Coralville Reservoir, Johnson County		The documentation form by Carl J. Bendorf is the only one submitted and forms the basis of this record. Other observers include Thomas Kent, Randy Graesser, John Van Ryebroek, Carol Thompson, and Dick Tetrault. \| Elimination of similar species: Laughing Gull: White in wingtips of adult gull doesn't fit. Bonaparte's Gull: Mantel color seemed too dark for adult bird and white tertial mark on mantel indicates a white trailing edge to wing which doesn't fit. Common Black-headed Gull: same problems as with Bonaparte's. \| The original documentation form event lasted from 13:00:00/13:30:00.	Iowa Ornithologists' Union \| MS 166	34	32