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Cat Island Chain Causeway – Green Bay Field Trip

Birders began gathering prior to 8:00 AM on September 12 at the park-and-ride near Hwy. 41 and Lineville Road, just northwest of the city of Green Bay. From there, the group did some carpooling and drove to the parking area near the east end of Lineville Road – where we started our hike out onto the long causeway that extends eastward out onto the Bay of Green Bay.

For the first part of the hike there were trees lining the roadway, and a few passerines were spotted – including Rose-breasted Grosbeak, Red-eyed Vireo, and Yellow-rumped and Blackpoll Warblers. For a time, a Bald Eagle was perched just a short distance ahead of us, providing great looks. Belted Kingfishers were observed along the shore, a couple of Marsh Wrens were heard in the cattails, along with a couple of Soras, a few Great Egrets were spotted, and a Wilson’s Snipe flushed from a little wet area.

Our group of 40 was led by Tom Prestby, who has been doing shorebird research here for the past couple of years. (Tom's research was partially funded through the WSO Research Grants program). Our group also heard an instructional lecture about the project from Janet Smith, a retired scientist with the US Fish and Wildlife Service. A Merlin was spotted flying past a short time later.

Further out along the causeway we encountered the first designated dredge fill area, for sand that has been dredged from the nearby harbor and navigation channel. The edge of the sand provides habitat for migrating shorebirds, and we were able to get good looks at Black-bellied and Semipalmated Plovers, American Golden-Plover, Sanderling, and Buff-breasted, Pectoral, Least and Baird’s Sandpipers. A little later, Long-billed Dowitcher was also observed here. We were told that nearby floating platforms had been utilized by nesting Common Terns during the breeding season.

A few birders decided to remain here at the shorebird site while the rest of the group continued walking eastward out along the causeway, and closer to Cat Island. Large flocks of gulls, cormorants and pelicans were increasingly evident – especially once the thousands of cormorants began to take off from the causeway ahead of us, upon our approach. Also spotted among the pelicans standing on the sand was a Ruddy Turnstone, which kept disappearing from view, until it finally came out in the open. A couple of small groups of ducks were present, which included Redhead, Lesser Scaup, Mallard and Blue-winged Teal.

On the hike back toward the parking area, at least one group of birders got to see an American Pipit that was walking around on the rocks. A couple of Ruddy Ducks were just offshore, swimming off to the north, Palm Warblers were also spotted in a couple of places, and a Philadelphia Vireo was observed in the trees.

Thanks to Tom Prestby for leading us on this rare opportunity to see this normally restricted area, but we are hoping that this field trip might be repeated again next year!

Tom Schultz, WSO Field Trips co-chair