Monday, August 10, 2015

Aug 10, 2015 - Fall Migration Precursor Post

Hello birding friends,

My name is Henry Griffin and I am the new author for "Arrivals and Influxes" and the various Illinois Migration Reports posted on IBET & IBF. Before I introduce myself and give the fall migration pre-cursor report, I would like to say a few things about Nick Minor. Nick is such an admirable young man - a true role model for me - and his scientific and ornithological knowledge seemingly knows no bounds - he is absolutely brilliant! Although I am continuing these reports, I will not even begin to live up to Nick Minor's astounding legacy of immense knowledge, impeccable attention to detail, and amazing devotion to the Illinois birding community through his absolutely astounding writing style of these reports.

I am 15 years old, a rising sophomore in high school (school starts for me on Tuesday, August 18), I play trumpet, piano, and I sing in the Voice of Chicago choir, and I have been a birder since February of 2012. My "spark bird" was a Cooper's Hawk that flew into my backyard and ever since then, my birding passion has led me to become a member of the Illinois Young Birders Club, lead free Oak Park Bird Walks in the spring and fall, and travel around the world looking for birds.

I have a solely birding blog, Birding Around the World, that chronicles my birding adventures, everything from leading morning bird walks to international trips. As I mentioned, I also lead free Oak Park Bird Walks during spring and fall to bring greater awareness for birds in suburban/urban areas. Feel free to contact me anytime:

Now, to the fall migration precursor report! I would like to give a rough outline of how and when I plan to post migration reports this fall: I will post again on Saturday, August 22 and will hopefully post nightly reports starting then (although I am very busy so some nights it won't be possible) until early November.

The period of calendar time when I post reports; however, does NOT dictate when fall migration exactly happens! I dare say, as Nick has written in the past, this southward migration could hardly even qualify as "fall" migration, in fact, it starts barely after spring migration has passed and actually continues through most of the winter! Also, although in this post I attempt to roughly outline when certain bird types will migrate, these are trends seen from the past and a number of climate- and weather-related factors such as climate change and even normal variation in weather from year to year literally change the calendar dates of migration every season.

In mid-to-late June, one may expect to already see or at least see reports of bird "dispersal;" that is, birds already meandering away from their breeding grounds because of failed attempts at breeding. This is common with shorebirds from northern, even Arctic, locales; however, I have also seen this happen with birds as different from them as American Redstarts!

July beckons the true beginning of shorebird migration where more and more failed breeding attempts start to mix in with true southbound migration of these brown and gray mudflat-lovers. Failed breeding attempts from songbirds and other species continue with even slightly greater intensity in July than in June. Orchard Oriole is a noteworthy songbird that actually regularly migrates southward in mid-to-late July.

Southbound shorebird migration is very long-winded, stretching from late June/early July all the way until early November in some extreme cases. You can see an example of this in's bar chart for shorebird occurrence in Illinois (on right); note the diverse times of year when various migrant shorebirds peak in abundance. For example, the Baird's Sandpiper appears to peak in abundance from August to mid September while to Dunlin peaks in October to even November in more southerly locations in Illinois!

August sees the peak number of shorebirds (again, the majority - not all of them) passing through Illinois on their trek to the Caribbean, Central, and South America (don't you wish you were a bird?). This month also brings about the true start to songbird migration, usually bringing in noticeable influxes of these birds starting in the last week of August.

Shorebird migration is still noteworthy but starts to slightly decline as the month of September wears on; however, songbird migration is on an "accelerando," as a musician would say, until about the last week in September when songbird's influxes peak in northern Illinois (note that this timing is a bit early for southern Illinois due to geographic location).

In October, songbird migration decreases while shorebirds begin to disappear at an even greater rate, while raptor migration is on the increase. Many raptors, such as the famed kettles of Broad-winged Hawks or that one nemesis Illinois Golden Eagle for you pass over in the month of October and can be readily viewed at hawk watch sites such as Greene Valley, Fort Sheridan, or Illinois Beach State Park. Also in October, one starts to see the arrival of late-migrating as well as winter species such as waterfowl, Winter Wren, Northern Shrike (late in the month), and, depending on the year and the amount of food at their breeding grounds, irruptive finch species (especially Pine Siskin).

November brings in the absolute last of the migrating songbirds and shorebirds (such as Dunlin, or hopefully Purple Sandpiper), dwindling raptor movement, and increasing numbers in waterfowl and winter species such as Common Merganser and Rough-legged Hawk.

Typically winter species such as the aforementioned Merg keep migrating and influxing into our area until early-to-mid December when winter avian patterns set in and migration pretty much quiets down until early March. One noteworthy aspect to winter birding; however, is the presence and odd "migrations" of irruptive species, which may, in their own right, classify as another type of (albeit higgledy-piggledy) migration.

So that's about what we should be expecting this year! As I already stated, migration varies from year to year and that's part of the reason why Nick Minor, and now I, try to give daily reports about the magical, enchanting disorder and confusion of, specifically southbound, migration.

What can we be expecting for the next 12 days until I post again? Increasing numbers of migrant shorebirds, especially at places like Emiquon, Chautauqua, and Lake Michigan locations as well as the first few arriving southbound songbirds at regular "migrant traps." We have already had evidence to both of these migration sub-categories so far this season with an abundance of shorebird reports as well as even reports of migrating songbirds such as the multiple Yellow-bellied Flycatchers that have been sighted recently, Pine Siskin & Olive-sided Flycatcher at Cantigny Park, Swainson's Thrush at Oldfield Oaks Forest Preserve, and even other types of migrating birds such as Josh Engel's recent Jaeger sighting.

Good migration-ing!

Birding Around the World
Oak Park Bird Walks

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