Have you ever heard of an omega block?

Dear Journey North Readers,

For the past couple of weeks, there has been a weather phenomenon over the country known as an omega block. This happens when there is a high-pressure area sandwiched between two low-pressure areas. The resulting wind flow creates a pattern resembling the Greek letter omega. 

These systems typically last a few days until a new system comes in and moves the others to the east. This system, however, stuck around a while because no other system moved in. As you can see in the satellite image, the areas under the lows are cloudy and rainy, whereas the areas under the highs are clear. 

So, what does this mean for spring bird migration? Well, it has meant that there has been poor flying weather at opposite ends of the country, but good flying weather in the middle, and this is reflected in the bird sightings. For example, in Louisiana over the past couple of weeks, 14 different warbler species have been seen, especially American Redstarts and Yellow Warblers. In Illinois, birders spotted 19 different warblers, with Blackpoll Warblers, Bay-breasted Warblers, and Blackburnian Warblers being numerous. Up in South Dakota, Gray Catbirds and Rose-breasted Grosbeaks have been particularly numerous, along with 11 different warbler species.

Towards the end of last week, the omega block had been pushed east, allowing birds in the east and west to continue migrating. Many catbirds were seen in Massachusetts, along with grosbeaks and orioles. Maine also recorded a lot of catbirds, grosbeaks, and orioles. Out west, California birders saw many Yellow-rumped Warblers, along with Olive-sided, Hammond’s, and Dusky Flycatchers. Violet-green Swallows made it to Washington, while Tree Swallows, Hammond’s Flycatchers, and Yellow-rumped Warblers were able to make it to Alaska!

So, how does this week look? There is a major storm system moving across the center of the country right now, bringing lots of rain and bad storms to the Great Plains and Midwest. That means poor flying conditions for a couple of days. Once the front passes, winds behind it will be pretty strong from the north (here in Tennessee, we have been in the upper 80s, but by the end of the week, we will be in the low 70s), so birds may still be grounded an extra day or two. That system will move east, bringing those same poor flying conditions by the middle and end of the week. Until then, birds have pretty good weather, so they had better get moving! Out west, the system has already cleared, so birds should be able to make good progress north this week.

Spring migration is winding down in the southern part of the U.S., but it is peaking in the central U.S. and just getting started farther north, so get out there and see what you can find! Take care.

David Aborn
Chattanooga, TN

Oriole and robin updates

By Jacob Swanson, Journey North

Hopefully, if you're located in the Eastern United States, you've seen your first Baltimore Oriole by now. I suspect most have, as we've received reports from as far north as Muriel Lake, Alberta (Latitude 54.2), courtesy of Rhonda. (But if you haven't, you can still report your sighting whenever it happens!)

I saw three orioles on May 9 here in Wisconsin, and a recent trip into northern Wisconsin gave me the opportunity to hear and see plenty of orioles along the banks of the Peshtigo River.

While my sightings weren't particularly early by this year's standards, it was fun to see all of the oriole activity going on. Others across the oriole's range have also enjoyed a few weeks of busy orioles visiting feeders and fruit trees, and singing from the trees.

"A rather soggy male ... flew into our Mountain Ash and took a berry or two," wrote Peter in Regina, Saskatchewan, on May 15.

"First Baltimore Oriole of the year this morning," Barbara in Brookline, New Hampshire, wrote on May 6. "Jelly and oranges are out, but he chose the suet instead!"

"Saw that they were close and just put an orange out today," wrote Alan in Kawartha Lakes, Ontario on May 6. "A female found it within hours."

We started to receive some reports of Bullock's Orioles in late April, with reports from Fallon, Nevada, and Emmett, Idaho, on May 29 and 30, respectively. We received a report from Sarah in Casper, Wyoming, having spotted an oriole on May 2, writing, "First made an appearance on May 2. At least one male has come back to the feeder every day since."

Nesting robins

Robins have been around for a while now, and in some cases, they may have never left, spending their winters braving out the snow close to northern breeding grounds.

Robins are some of the most familiar nesting birds, as they often make their nests on or under decks, on ledges of homes or garages, or in trees close to our homes. 

While these nests may sometimes be a little inconvenient, it does provide backyard birders with the opportunity to follow along throughout the entire nesting process.

"Two always hungry baby robins in the nest," wrote John in Northfield, Minnesota, on May 4.

In Union, Nebraska, Linda reported a robin nesting "by the window air conditioner at our Lake Waconda cabin."

You can report sightings of nesting behavior to Journey North throughout the summer, as well as sightings of monarch butterflies and milkweed.