| UID |
|
| Digital Object Type |
Rare birds documentation form |
| Content DM Link |
https://n2t.net/ark:/87292/w94f1mm79 |
| Type |
Image, Text |
| Description |
Records Committee review for an Iceland Gull at Red Rock Reservoir Dam in Marion County, IA on March 19, 1997. Includes a record review document with votes, photocopies of three photographs, an article in American Birds, an article in Birding, an article in Iowa Bird Life, correspondence about related bird sightings and review, documentation form for a related sighting and review, and a documentation form submitted to the committee for this review. |
| Related Genres |
Administrative records Clippings (information artifacts) Correspondence Field notes Photographs |
| Sort Date |
1997-03-19 - 2000-11-24 |
| People / Organizations |
|
| Time |
2:20 PM |
| Rights |
This complex item has mixed rights protection. Portions in which Iowa State University is the copyright holder are made available for non-commercial use, including sharing and adapting the work. No permission is required for non-commercial use to these portions so long as attribution is provided. All other uses of these portions, including commercial, require permission from the Iowa State University Library Special Collections and University Archives (archives@iastate.edu). (CC BY-NC 4.0 International). Portions in which Iowa State University is not the copyright holder are believed to be under copyright, but either (a) no rights-holder(s) have been identified or (b) one or more rights-holder(s) have been identified but none have been located. If you have any information that can contribute to identifying or locating the rights-holder(s) please notify the Iowa State University Library Digital Initiatives Program (digital@iastate.edu). (Rightsstatements.org InC-RUU 1.0). The original object is available at the Iowa State University Library Special Collections and University Archives (archives@iastate.edu). |
| Data Access Rights |
http://vertnet.org/resources/norms.html |
| Data License |
http://creativecommons.org/publicdomain/zero/1.0 |
| Collection |
Iowa Ornithologists' Union | MS 166 |
| Box |
11 |
| Folder |
4 |
| Contributing Institution |
Iowa State University Library Special Collections and University Archives |
| Creator / Author |
Brees, Aaron |
| Contributors |
Jorgensen, Joel G. Silcock, W. Ross Lehman, Paul Iowa Ornithologists' Union Records Committee |
| Topics |
Bird watching Ornithology Ornithology--Societies, etc |
| Birds |
Iceland Gull |
| Locations |
Red Rock Dam |
| Map |
|
| Verbatim Locality |
Red Rock Dam, Marion County, Iowa |
| Location Remarks |
The documentation forms do not include georeferences |
| Habitat |
rock bar below dam, in association with Ring-billed and Herring Gulls |
| Extent |
13 pages |
| Language(s) |
eng |
| Bibliographic Citation |
|
| Information Withheld |
|
| Individual Count |
1 |
| Occurrence Remarks |
|
| Occurrence Status |
present |
| Field Number |
1997-09 |
| Event Remarks |
The documentation form by Aaron Brees is the only one submitted and forms the basis of this record. | Elimination of similar species: 1st year Glaucous Gull: Eliminated two ways. 1) Overall size. This bird was smaller than a Herring Gull, compared with Glaucous, which varies in size from Herring to Great Black-backed Gull. 2) Bill pattern and structure. This birds' bill was very small and thin. Also, first year Glaucous bills have a clearly defined black tip and a basal section that varies from flesh-pink to yellowish-cream. This birds bill was all dark with the tip being slightly darker and not clearly defined. Grant, referring to Glaucous and Iceland Gulls, states that "size alone is a valid distinction for individuals which are...obviously smaller than an average Herring Gull" and "On first-years there is a diagnostic difference in bill pattern. Glaucous Gull always has the basal two-thirds brght [sic] flesh-pink to yellowish-cream and a sharply contrasting, square-cut black tip.." and "At long range, the bill may look wholly dark, which is never the case on Glaucous. The bill pattern difference holds good throughout the first year at least...(Grant 1986)." 1st year Thayer's Gull: Eliminated several ways: 1) Overall color. This bird was basically pure white, compared to Thayer's which comes in various shades of brown depending on the individual. 2) Lack of a dark secondary bar. Thayer's Gull, in flight, shows a dark secondary bar consisting of a broken row of dark spots. Iceland Gulls show no dark secondary bar of any type, and this bird did not show any dark, contrasting feather groups on the wings. 3) Lack of contrast between tail and uppertail coverts. Thayer's Gull generally shows a dark tail contrasting with lighter uppertail coverts. Iceland Gull generally shows non-contrasting tail and uppertail coverts, which was the case with this bird. 4) Some minor details that are not diagnostic, but point to Iceland Gull: This bird had no markings on the head, while Thayer's Gull often (usually?) shows a dark smudge through the eye; This birds legs were very pale pink, while Thayer's Gull is said to average brighter pink than similar species, including Iceland Gull. | The original documentation form event lasted from 14:20:00Z/14:56:00Z. |
| Supporting Documentation |
Kaufmann K. Kaufman field guide to advanced birding. Peterson Field Guide Series. New York: Houghton Mifflin Harcourt; 1990. | Grant, PJ. Gulls: a guide to identification. 2nd edition. Cambridge, MA: Academic Press; 1986. |
| Date Digital |
30 May 2017 |
| File Type |
image/jpeg |
| Hardware / Software |
Epson - sheet feed |
