Posted by: NatureIsAwesome | October 10, 2013 @ 3:00 am

Diurnal Migration of Passerines over the Florida Keys

For years Mariel and I have been watching radar loops of targets we have always presumed to be birds flying south along the west coast of FL during October. After a few years of sending Rafael Galvez of Florida Keys Hawkwatch radar images and calls on the phone, we finally hit pay dirt today!

Late Tuesday morning Mariel and I were sending each other images and talking about a massive flight that was occurring into the day. We decided to contact Rafael and ask if he was seeing any migrants overhead, he answered “Thanks, slow so far”. We continued to monitor the flight on radar and just when we said, well they got away again; Rafael text us “It just happened!!!!” this is the first time we have been able to get it right! Rafael wrote a great blog post about the event, check it out here

Lets step back a bit to investigate what happened on this day and what lead to the awesome flights of songbirds over the FKH Platform.

A large migratory flight took place over the Mid-West south to peninsular Florida on Monday night.

A large migratory flight took place over the Mid-West, south to peninsular Florida on Monday night.

Fast forward to Tuesday mid-morning, winds were favorable for a continual flight over the Gulf of Mexico. Northwest winds were building in behind the cold front which by this point had taken a stance over central north Florida. Precipitation had moved off into the Atlantic allowing birds to fly south over the Gulf without interruption. Winds continued to give birds a tailwind, the mass of the flight bypassed the first likely place to see a fallout, Fort De Soto. Radar images continued to show what we believed were birds, at this point we knew that all signs pointed to the returns indeed being birds, but we wanted to see if we could actually see them.

Cold front moves south, birds aloft over Gulf of Mexico heading south.

Cold front moves south, birds are aloft well into the day heading south over the Gulf of Mexico.

Diurnal flight of birds heading south over the Gulf of Mexico

Diurnal flight of birds heading south over the Gulf of Mexico

Miami radar detects the movement along the west coast of the state.

Miami radar detects the movement along the west coast of the state.

By Tuesday afternoon we had sent several images to Rafael and were still hopeful that this talented and skilled watcher of the skies would pick out these birds. We continued tracking the movement as it started to head south into FL Bay and consequently over the FL Keys. At this point it was make it or break it, just then we received a text message from Rafael:

It Just Happened!!!!!

We sent him the images below, the first a velocity image showing birds approaching the FL Keys. The second image is a reflectivity image which is great for detecting birds in the atmosphere as you can see here, and the third image is the corresponding velocity image to the prior image, we used this data to determine the speed at which targets were moving.

Birds moving NW–>SE at 15-26kts

Birds moving NW–>SE at 15-26kts

The text line started to ring…

Rafael: Incredibly high above, hundreds heading straight for Cuba!!!!
Passerines picked out SUTA and EAKI, but mostly UNIDs

All we could reply with was, WOW!!! We also replied with “guessing warblers should be about two hours behind. You may have a busy transect count tomorrow a.m.”, but to our surprise warblers were mixed up with this flight.


We replied: “wow cool we would have thought the kingbirds and tanagers would out-fly smaller slower moving birds. AWESOME GROUND TRUTH. THANKS BUD!!!!

Late afternoon synoptic map, you can see birds still aloft even as sunset closed in.

Late afternoon synoptic map, you can see birds still aloft even as sunset closed in.

Later in the evening we spoke with Raf and exchanged thoughts on the success of detecting and documenting the flight over Curry Hammock State Park where the Florida Keys Hawkwatch is located. As they closed up the station for the day a shower dropped some rain and birds, “Big Bob” a large buttonwood which is used as a landmark at the hawkwatch was loaded with warblers. Here is a list of what was turned up…

Soon afterward, we were pacing the buttonwoods adjacent to the hawkwatch. “Big Bob” – the large Buttonwood visible from the count site and used as a key landmark, was covered in warblers. Within the 1-acre parcel of habitat surrounding “Big Bob,” we found excellent birding:


Tennessee Warbler 14
Nashville Warbler 2
Blackburnian Warbler 3
Chestnut-sided Warbler 3
Black-throated Green Warbler 3
Ovenbird 4
Yellow-throated Warbler 2
Palm Warbler 20
Northern Parula 4
Magnolia Warbler 1
Common Yellowthroat 4
Prairie Warbler 1
American Redstart 4
Worm-eating Warbler 1
Hooded Warbler 1
Yellow Warbler 1
Red-eyed Vireo 3
White-eyed Vireo 2
Eastern Wood-Pewee 1
Indigo Bunting 12
Blue Grosbeak 1
Rose-breasted Grosbeak 1
Baltimore Oriole 1
Blue-gray Gnatcatcher 3
Northern Cardinal 5

And this was just one tree and its surrounding plot!



What an awesome experience!

Nature is Awesome
Angel & Mariel


  1. Fascinating and exciting!!! I see the Badbirdz icon is on the TAS Bird Board now too!

  2. Great job Mariel and Angel; the arduous monitoring finally pays off! My first thought is – “let’s do it again.” But I guess that is not entirely up to us. Down here we’ve found this occurrence to be greatly motivating. Weather events combined with radar-detected movements hold promise, but are not frequently detectable in the Keys. Seeing it all “mapped out” in the way you’ve shown it here gives us additional fuel to get up every morning and monitor those skies. Keep up the awesome work!!!