Idaho Bird Records Committee Rarities Report Form

Species: Glossy Ibis / Plegadis falcinellus

Reporter: Cliff Weisse, 4125 Beaver Springs Rd., Island Park, ID 83429, 208-558-7789, cliffandlisa@octobersetters.com

Other Observers:

Date of Observation: 4-28-2006

Date Report Prepared: 4-28-2006

Locality of Observation: Camas NWR, about ½ mile south of the main parking lot

Habitat: Flooded field

Conditions: Sunny with intermittent wind. Angle of sun was mostly behind the birds but occasionally it lit up the front side of the birds. The sun was high so it was not directly behind the birds.

Did you take notes…

No

Did you consult a field guide or other reference work?

during the observation? Yes

later the same day? Yes

What guide or reference did you consult?

Sibley Guide to Birds

Description: Two adult Plegadis-type Ibis as follows:

Size, structure, and plumage inseparable from surrounding White-faced Ibis except:

-Bills brownish, not gray

-Legs dull grayish with deep red (not bright orange red) “knees”.

-Facial skin blue

-Border of facial skin sharply demarcated pale powder blue lines confined to facial skin only; feathers surrounding facial skin entirely dark. Between eye and bill top edge of border widened slightly between eye and base of mandible; lower border consistent width along entire length

-Light border on edge of facial skin extended completely across forehead along base of bill but did not extend around eye, rather it ended abruptly at eye

-No hint of any red color on head or face

-No hint of red color to iris

Behavior: Foraging in field that was being flooded with about 50 White-faced Ibis. The flock these two were in contained about 15 White-faced Ibis. Occasionally both birds would preen and both birds roosted several times right in the field where they were foraging. Neither bird was seen to interact with any other individual in the flock or with each other. If they were a male/female pair I was not able to tell that they were staying close together. At times they were as far as 40 yards apart and at other times they were right next to each other, as close as 2 feet apart.

How and when did you positively identify the bird, and what clinched the identification for you? When I first got one of these birds in the scope (60X @ approximately 80-100 yards) it was foraging with head not visible. It picked its head up briefly three or four times and I got a glimpse of the facial pattern. After about one minute it lifted its head and held still for several seconds giving me a very good look at the facial pattern, which is diagnostic in this plumage.

How did you eliminate similar species, and what were they? The only other species that could be confused with Glossy Ibis is White-faced Ibis. Points that eliminate White-faced Ibis include:

-Iris color dark, not red as in White-faced. Immature White-faced have a dark iris but these birds were clearly adults in full breeding plumage.

-Leg color, gray with red knees consistent with Glossy but wrong for White-faced. Transitional plumages may show similar pattern (I don’t know that they do but I can’t say for sure that they don’t) but again, these are obviously in full breeding plumage.

-Facial pattern, light blue edges on blue facial skin with entirely dark feathers surrounding facial skin and no white behind eye is diagnostic for Glossy Ibis. White color of edges around facial skin on White-faced is on the feathers, not the facial skin, and extends entirely around eye. Facial skin is red on White-faced. Some White-faced, including one immature individual present in same field as these individuals, show very thin white edge around facial skin but it still extends around eye and is in the feathers not on the facial skin. Facial skin still show some reddish coloration. This facial pattern is all wrong for any age or plumage White-faced Ibis and is entirely typical for Glossy.

Experience with this species: No previous experience with Glossy Ibis but I have seen thousands of White-faced over the years and studied details of facial pattern on hundreds during the last two years in both spring and fall.

General experience birding: 13 years

Were photo(s), video, and/or audio obtained by you? Yes, see below.

This photo is of both individuals but the grass across the face of the right bird makes it difficult to see the details of the facial pattern. The two photos below are of one bird and show details of the facial pattern better.