Ring-Billed Gull at Lunch: Pelican Lake, Saskatchewan

The gull let out a screech
and headed for the centre
of the lake.© SB

I saw this gull over Pelican Lake, along Thunder Creek near Moose Jaw, Saskatchewan.

The gull saw something just below the surface of the water, shrieked and flew out, then pounced.

I wonder what it caught...

A fish with long, thin fins?

A large yellow salamander?

A turtle? (The visible part looks a bit like that, but the shape beneath the water looks far more elongated.)

I didn't see the action until the pictures were taken; my camera sees farther than me.

Gull aiming to grab the long yellow creature,
just below the surface. © SB

Gull with lunch. Whatever it may be. © SB

What is this?  I think it's likely a ring-billed gull from its colour and the hint of a dark mark on its beak That's the most common gull in Saskatchewan at this time of year.        
Location: At the Ducks Unlimited viewing location, west side of Pelican Lake, north-west of Moose Jaw, Saskatchewan. (There is also a PL in the far north of SK, which I have yet to visit.)   
Photo date: March 31, 2012. 

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