Wm. C. Sterling State Park in Monroe Co., MI. The bird was swimming with a Common Loon (Gavia immer) in the 1st lagoon to the right as you enter the park from Dixie Hwy, and was visible from the small parking lot next to the bike path. Back to the car...
Robin and I arrived at Sterling St. Park shortly after 2 pm and found Allen Chartier, Scott Jennex, Todd Palgut, Sean Bachmann and Tex Wells scoping the Pacific Loon. Both the Pacific and Common Loons were at the south end of the lagoon near the walking bridge and swimming among a large raft of Red-breasted Mergansers. The loons had just been in the SW corner of the lagoon, next to the parking lot, where everyone had great looks. If we waited long enough, they'd be swimming back. The birds seemed to be cruising and diving the lagoon in a somewhat circular pattern, moving from one end to the other over the course of 20 - 30 minutes.
Bonaparte's Gulls that were working the shoreline.
The birds moved off toward the middle of the lagoon, so we drove back toward the south end of the lagoon. I had hoped to get them in better light as they made their circuit, so I was disappointed when they remained at the north end of the lagoon for the next 45 minutes. I could only sit in the brush and scope them from a 1/4 mile away while Cathy Carroll, Rodney Laura, and Jim Fowler viewed them from a few feet away.
I'd been sitting on a large piece of canvas that was on the shoreline, and was startled when a field mouse started squirming underneath my hand. I turned to see it scamper over my hand and run into the brush.
With no evidence that the loons were going to move from their location, I checked my camera and found that I had only a couple of frames left. I had no other SD cards in my vest, so I realized that it was useless to stick around. We headed back to the north side of the lagoon where I took my last few pics of the loon as it began to swim along the west shoreline (back to the south...). Time to head home. It was 10:30 am.
Pacific (G. pacifica) vs. Common (G. immer) Loons
With both birds spending much of their time together, it was a wonderful opportunity to compare and contrast their forms. The backlit conditions with which I did much of my photographing actually helped to enhance their differences.
At 25-26" the Pacific Loon is smaller than the Common Loon (32"). This is evident when you see both birds together. In the image above the Pacific Loon is on the left, while the Common Loon is on the right. Note also that the bill on the Pacific Loon is smaller, slimmer and straight, while the Common Loon has a much larger, heavier-looking bill. The Pacific Loon has a thinner neck, and a smooth, rounded head while the Common Loon shows a thicker neck and a squared head with almost a flat top. While watching the two birds swim it is also important to note that the Pacific Loon tends to ride high on the water, while the Common swims very low to the water. Both birds appear to be juveniles based on the white edgings to the back feathers, giving them a somewhat checkerboard or scalloped appearance.
In these two images we see the differences in their relative buoyancy. Note that the Pacific Loon has a necklace at the base of the neck, and contrasting white throat w/ gray nape and finely streaked sides. The Common Loon shows a broken neck band and a smudgy white throat.
Hopefully I can get back down there this week to get some pics w/ the sun at my back...