A Perplexing Gull

On Saturday, November 11th, 2017 a group of us came across a Gull at the outlet tubes at John Redmond Reservoir in Coffey County Kansas that peaked our interests. Here are my thoughts on a bird that some felt comfortable with an identification, some took time to study and changed their identification, and where a consensus was not reached even by the people that felt comfortable identifying it. If you are not a fan of long-stories, then know that I am confused by this bird and do not feel comfortable identifying it. I also write this blog post to help me remember the thought process I went through trying to identify the bird. For reference, here are the parts of a gull. 

Observation 

The bird sat on the cement structures below the water outlet and occasionally stretched but it never flew in the time we were there. The sky was overcast and a light drizzle fell intermittently that morning. Initially observed at 225 yards we walked closer and were able to take a few photos and study it with scopes at 100 yards. 

The bird of interest is the bottom one. Adult Ring-billed Gulls are in the background for comparison.

There are a couple of characteristics about this bird that might lead us toward an identification. The bird is only slightly larger than the adult Ring-billed Gulls, it has a lighter head and neck that contrasts with a grey-buff colored chest and dark primaries and wing coverts, it has bright pink legs and a dark bill. Focusing first on size, the regularly occurring species in Kansas to consider are California Gull, Iceland Gull, Lesser Black-Backed Gull, and Herring Gull.

A side profile offers insight into the structure as well as earlier characteristics.

Size might indicate that California Gull as a candidate species for identification. I feel safe that this bird is not a California Gull however based on the light head, all dark bill, and contrasting parts of this bird. With a 1st winter California Gull I would have expected a warmer brown color of the bird on the wing coverts and a clearly demarcated bi-colored bill with black tip and fleshy pink colored base. 

A 1st winter Iceland (Thayeri) Gull is potentially a better fit. Indeed this bird exhibits bright pink legs, an all dark bill and the size of the bird fits within the expected range. Additionally, the tertials are frosted and the coverts are fairly cleanly marked. So far so good, but there are a couple of characteristics about this bird that seem to go against the expected field-marks. The contrast between the warm chest, lighter head, and the darker primaries point away from an Iceland Gull. In addition, Iceland Gull’s tend to have a rounder head than the block-shaped head of this bird. Overall the contrast on this bird is not something I expect for a species that is often, on average, lighter. 

This leaves two likely possibilities. The small size, the all dark bill, the lighter head compared to the darker primaries and relatively patterned coverts had us thinking Lesser-Black Backed Gull. The warm buffy chest tones, the overall potbellied shape, and the dark but not black primaries were reasons toward Herring Gull. If the bird had flown we would have been able to examine the wings and tail in flight, but we left without seeing either.

 

Here are limited views of the wings and uppertail coverts.

I wish that I could deduce that there was something in these photos that led me to reach a concrete conclusion, but instead I choose to leave this bird unidentified and let it fall within that “interesting” category. The overall uniform gray/brown wash on the belly, shape, and unexplainable feel of the bird are sufficient that I believe this bird is most likely a Herring Gull but does that really matter. Perhaps I could exploit my instincts if I were a betting person with a definitive expert willing to ID this bird or perhaps I would loose so much money that I would give up birding and identification completely. An easier answer would be for me to have a greater knowledge based, as the details of the coverts and tertials might provide insight.  

So some that saw this bird in person or through electronic communications identified it as a Herring Gull, a Lesser-Black Backed Gull, a rarer Vega Herring Gull, and I even had thoughts of a Laurus genetic hybrid concoction initially. These photos are not as challenging as the mind-bending result of another mystery bird yet it is puzzling. Fortunately I like the ambiguity and opportunity presented by my apparent lack of Gull knowledge. At least that is what I tell anyone that believes me as a reason to get out more often.