When to go birding this spring

Plus, an update on Flaco.

TWiB photo illustration.

Longtime TWiB reader and friend Paul asked a question recently, and it’s likely one that many readers wonder about. When exactly should we look for birds at a local hotspot in spring migration?

Here in Chicago, there’s Montrose Point Bird Sanctuary, a parcel that is the most heavily birded in the state and No. 1 for species all-time. But this advice goes for other hotspots like Indiana Dunes, Point Pelee, Magee Marsh, Whitefish Point, and Presque Isle, too. Likely Central Park and Cape May as well, though the migration timeframe may differ.

Pick a day from about May 10 through May 20. Look for winds out of the south that birds are going to use to help propel them in migration. Check out a tool like Birdcast to see if big movements of birds are showing up on radar. It doesn’t hurt to check your local bird alert or eBird either.

There are days that even the best hotspot will be relatively quiet. This brings to mind the hotshot birder arriving from one of the coasts only to gripe about the 45 degree temperatures and rain all day. Some days can be duds even in spring migration.

Even then, sometimes winds will shift rapidly from south to north and a fallout will occur. This can result in large amounts of birds in some fairly inclement weather. (Again, there are exceptions.)

One more thing: stay at the spot for a while. Be patient. Birds are moving through constantly and conditions change minute to minute and hour to hour. An initial traverse of a preserve may not turn up much. A second go-around may turn up a lot more.

Follow these guidelines, and you’ll likely see a few birds. One can’t go wrong when mid-May arrives at your nearest hotspot.

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Flaco’s necropsy results

Thanks to TWiB subscriber Tony Fitzpatrick for this image of one of his iconic collages. Check out some more of Tony’s work here.

Just as the ink was drying on March 25’s newsletter, news came across that Flaco the Eurasian Eagle-Owl died with high levels of rat poison in his system. As you might recall, the big raptor had been delighting Manhattan residents since making it out of its zoo enclosure about a year ago.

Flaco was presumed to have died due to blunt force trauma, or a building collision. Reports, though, suggested that Flaco fell from a perch when he died, which seems odd. The story is indeed nuanced—there also were signs of a severe pigeon virus.

From a New York Times report:

Initial necropsy findings released the day after what onlookers described as a deadly building strike suggested Flaco had sustained an acute traumatic injury to his body, with signs of substantial hemorrhage under his sternum and in his back near his liver.

And more detail from the Wildlife Conservation Society:

In confirming the role of traumatic injuries, those tests found he had a severe pigeon herpesvirus, which the conservation society attributed to his eating feral pigeons.

The herpesvirus in question can be carried by healthy pigeons but may cause fatal disease in birds of prey, including owls that become infected by eating pigeons, the society said.

In Flaco’s case, the society said, the viral infection had caused severe tissue damage and inflammation in many organs, including the spleen, liver, gastrointestinal tract, bone marrow and brain.

Toxicity tests also determined that Flaco had been exposed to four different anticoagulant rodenticides that are commonly used for rat control in New York City.

Together, the conservation society said, the pigeon virus and rodenticide exposure “would have been debilitating and ultimately fatal, even without a traumatic injury, and may have predisposed him to flying into or falling from the building.”

As other remembrances have noted, maybe Flaco never really had a chance in the highly urban ecosystem of New York City. But he inspired many of us by surviving for as long as he did.

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Checking in on Piping Plovers

The Great Lakes Piping Plover Conservation Team has been keeping tabs on Piping Plovers as migration and nesting season approaches. First there was a Great Lakes bird in breeding plumage at Dauphin Island, Alabama:

glpipl

A post shared by @glpipl

Then there was another update on a Sleeping Bear Dunes nester, IRV, at Yum Balam, Yucatan, Mexico:

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A post shared by @glpipl

While no Piping Plovers have been reported on the Great Lakes at the time of this writing, there’s a good chance the next warm front will bring some shorebirds with it.

Parting shot

Bahama Woodstar. Photo by Bob Dolgan, March 29, 2024.