Sunday, June 15, 2014

A Mini Tern and Gull Workshop from the Great Basin

Malheur NWR provided us with an unexpected opportunity to see and learn about a few species of gulls and terns that we previously knew little about. Keep in mind Malheur is located in the Great Basin of the United States. Gulls and terns are the last species that we expected to see here. But in fact, during breeding season they are quite common.

 We were just finishing up a long day of counting Sandhill Cranes and were surprised to be visited by a large group of newly arrived Black Terns. Black Terns winter in South America and breed in a few areas of North America including Malheur NWR.  We had seen them in the Klamath Basin before but from a distance that made it difficult to get good views. Here we were presented with the opportunity to really get to know the Black Tern.

The Black Terns began hanging out at Marshall Pond located at Malheur HQ so we had more opportunity to watch these beautiful creatures as they fed on insects and fish.

As part of our Boca Lake marsh survey we also had the wonderful experience of seeing the Black Terns nesting in the marshy areas -see photo below. The dark spots are the Black Terns sitting on their nests amongst the Eared Grebes and other waterfowl. Just imagine there are hundreds and hundreds of these "nesting spots" in this lake.

Another gull we had an opportunity to see was Bonaparte's Gulls. Unlike the Black Terns, the Bonaparte's Gulls simply pass through the Malheur NWR on their way to their nesting grounds up north. We thought we were too late to see them but were surprised one day with a small group of adult and immature Bonaparte's flying through feeding on the insects at the water's surface. We had an amazing chance to really get to see the differences and similarities of the adult and immature Bonaparte's Gulls! The white outer primaries and black trailing edge on the wings help me to tell the difference between the Franklin's and Bonaparte's Gull as well as Bonaparte's partial eye ring is not as intense as the Franklin's.

This encounter with the Bonaparte's was really helpful since they look very similar at first glance to the Franklin's Gull which breeds in the area. Like Black Terns, Franklin's winter in South America, specifically along the Pacific west coast. We have mentioned that Franklin's Gull is one of our favorite birds because, as they fly in large groups, they sound like laughter from the sky. These gulls are colonial nesters which means they nest together even though they are monogamous. See photos below.

Note the red/rosy blush on the Franklin's chest.

Caspian and Forester's Terns look similar from a distance. A closer look helps to identify the Caspian Tern as being much larger with an all orange bill. Malheur NWR recently built an artificial island on the refuge to encourage greater breeding of the Caspian Terns in order to predate the young carp and to minimize their impact on Columbia River juvenile salmon.

The Forester's Tern is a smaller tern with a black tip on the bill and has a deeply forked tail.

Ring-billed Gulls can be confused with California Gulls but easily differentiated by their yellow eye during breeding season. See the distinguished yellow eye of the Ring-billed Gull below:

The world is full of beauty and wonder:)

Turtle and Hawk

PS- we are preparing to leave Malheur NWR for the Zumwalt Prairie Preserve in one week. We will be there through the end of August. We will be much more remote and have very limited access to phone or internet for weeks at a time.

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