Tree islands provide protection for coastal egrets during Hurricane Irma

What do you think Reddish Egrets living along the Gulf Coast of Florida did during Category 4 Hurricane Irma?  If you’ll recall, we have been tracking six of these birds for several years with GPS-enabled satellite transmitters. Five were outfitted with these amazing devices on and near Sanibel Island’s J. N. “Ding” Darling National Wildlife Refuge; one was tagged near a remote shore in Dixie County, Florida.

San Carlos (left) and an unmarked Reddish Egret at San Carlos Bay -Bunche Beach Preserve.
Photo credit Teresa Hedden 2017.

Think about Reddish Egrets. Picture these one-and-a-half pound bundles of feathers bobbing and weaving in coastal shallows and lofting gently over the reclining mangrove forest. Now imagine winds that can lift roofs off houses and storm surges that can over-wash these placid mangroves. How many of these birds do you think survived Hurricane Irma? If you’re like us, you probably did not feel optimistic as Irma played out, even wondering if any of these birds could have lived to keep telling us their stories.

Well, thanks to marvelous technology and the generosity of many organizations and individuals, ARCI has the answer for you: Every one of them. That’s right. Not one of our tracked Reddish Egrets succumbed to Irma’s terrible beating.  And, they all survived while hunkering down in the places we’ve come to know as their favorite roosts, embedded within the small coastal landscape that includes all their favorite feeding places.

As Hurricane Irma approached, Ding#1 and Ding#2, tagged in June and October of 2014 respectively, were near the Wildlife Drive, J. N. “Ding” Darling National Wildlife Refuge, on Sanibel Island. The tracking data revealed that they were using roost sites on the small islands to the east of the observation tower, plus the interior mangrove ponds that were likely granted some protection from the wind. 

Bunche Beach, ARCI's
only tagged white-morph
Reddish Egret. Photo credit
Janet Kirk 2016.

The two mainland Reddish Egrets, San Carlos and Bunche Beach tagged in January 2016, moved among the small creeks rising in the “uplands” (it’s all relative) bordering the shoreline and extensive foraging flats of the San Carlos Bay-Bunche Beach Preserve that end abruptly at the municipal boundary of densely-developed Fort Myers Beach.

Darling, tagged near the Wildlife Drive in January 2016, spent the worst part of the storm just inside the dense mangrove stand on the south end of Pine Island. Shortly after the storm abated, he flew to the east side of Sanibel, one of his typical foraging areas.

Our sixth Reddish Egret, Hagen, tagged in the Big Bend Wildlife Management Area of Dixie County in December, 2014, remained for two days on one of his habitual roosting islands, which is three miles south of his core foraging area. After the storm passed, he resumed his regular routine.

Obviously these birds endured the strong winds, heavy rains, and menacing storm surge associated with Hurricane Irma.  Their inland flights documented by telemetry early in the storm may have resulted from a storm surge forcing them to find higher ground. Foraging areas days later were in isolated ponds away from the coast, which probably were shallow enough to permit feeding. Foraging conditions may have been enhanced in such sites because over-wash would have introduced fish that became entrapped as the water receded.

We hope that other birds, including Reddish Egrets and all the other species that grace Florida’s skies, did as well as these individuals that share their secrets with us every day, teaching us – electronically – what we need to know to help protect their future.

Who stayed, who left? Where our birds are after Hurricane Irma

Were you able to catch ARCI’s Executive Director, Dr. Ken Meyer, on a panel of researchers talking about how Hurricane Irma could have affected Florida’s imperiled species? Ken was interviewed on National Public Radio’s Science Friday on 15 September.  Here’s a link to the segment, in case you missed it:

How Hurricane Irma could affect Florida's endangered species

We would like to share some great news about our remotely-tracked birds that were in the path of Hurricane Irma in Puerto Rico, Cuba, the Bahamas, Jamaica, the Florida Keys, and throughout the Florida Peninsula.   We are getting normal-looking movement data on all but a few of the birds!  Those we have not heard from include one White-crowned Pigeon on Grand Bahama and another that had just migrated to Cuba ahead of the storm.  We will keep watching for signals from these birds.

Six Gulf Coast Reddish Egrets (five in Lee County on J. N. Ding Darling National Wildlife Refuge and well north in Dixie County) stayed in place for the storm and, based on their movements compared with pre-hurricane days, appear to be doing well.  The single Magnificent Frigatebird we are tracking at this time, an adult from the only U. S. breeding colony in the Dry Tortugas that spends this part of the year off the Gulf coast of Citrus County, Florida, rode out the storm over the Gulf. He headed west and then south on the cyclonic flow that eventually carried this bird along a 600-mile loop that brought it right back to its favorite near-shore roosting island.

The four satellite-tracked Snail Kites sat tight in south Florida wetlands. The same is true for the Short-tailed Hawk we recently tagged in St. Petersburg, Florida, which promptly returned to its nesting forest at Sawgrass Lake Park.

The GSM/GPS-tracked Swallow-tailed Kite Apopka had the best migratory conditions on the north winds carried in with Irma.  She covered ground fast and got to the south coast of Cuba the night before the storm hit Cuba’s north coast.  She remains in Cuba still today.

Location of 37 remotely-tracked birds after Hurricane Irma had passed. The two yellow "Missing" markers refer to two White-crowned Pigeons from whom we have not yet received data.

We will be flying this week and again soon after to check on our VHF radio-tagged Southeastern American Kestrels, Snail Kites, and 12 more White-crowned Pigeons.  This also will be our best opportunity to assess habitat impacts on all our study populations.  We’ll also be elaborating on each species’ immediate responses to Hurricane Irma in the upcoming blog stories.  We are amazed at their resilience!  More soon.

Nowhere to go. How will our birds cope with Hurricane Irma?

In preparation for Hurricane Irma, we evacuated field sites in the Florida Keys and coastal south Florida, moved boats and field crew to northern latitudes, and fortified our homes. We know that many of our supporters and those who will read this blog have been affected by this massive storm and we hope that you stayed as safe as possible.

Of course, something we cannot personally protect from a hurricane are wild birds, including the ones we tag and study. Severe weather such as this presents us with interesting, unplanned opportunities.  With satellite, cell-phone, and old-fashioned radio tracking, ARCI is following 37 individual birds of seven species, a rare and valuable chance to learn how they weather this hurricane and respond to its profound impacts on the many habitats, special places, and landscapes that support their day-to-day lives. Some birds will perish in the extreme conditions. Some will lose resources essential in the near term, or suffer higher risks of mortality or impaired reproduction, long after the storm passes. Others may begin their seasonal migrations only to be forced to take up novel routes that prove threatening or take them to unsuitable wintering destinations.  Others may accomplish the impossible, against all odds, and survive in spite of the enormous scale of the damage, giving us some hope that wild birds will be resilient enough to cope with nature, and with all we do to jeopardize their continued existence.

The 37 birds telling us these stories are the ones we’ve carefully captured, tagged, and tracked with the support many of you have generously provided, including Swallow-tailed Kites, Snail Kites, Magnificent Frigatebirds, Reddish Egrets, Southeastern American Kestrels, White-crowned Pigeons, and a Short-tailed Hawk.

Most of our Swallow-tailed Kites are in Central and South America now, but there are some lingering in Florida, including “Apopka”, a cell phone/GPS-tracked bird that we featured in our last blog.  We hope Apopka was encouraged to begin migrating by the strong northern tailwinds on the leading edge of the advancing hurricane. We are watching closely and hope to have more for you soon.

Four of the seven species we are tracking in the Florida peninsula will not migrate: eight Snail Kites tagged in south-central Florida (satellite and VHF radio transmitters), a single Short-tailed Hawk fitted with a cell-phone/GPS device in St. Petersburg, six Reddish Egrets from coastal Lee and Dixie counties tracked with satellite/GPS technology, and four young Southeastern American Kestrels tagged with tiny VHF transmitters in Hillsborough County. We can only hope they will find a good perch and hang on, or take to the air and evade - or endure - the most extreme conditions. Although we do not know what strategies they employ, or which work best, we have learned from past experiences to expect some surprises when tracking birds that encounter exceptionally severe weather. For instance, we watched in 2016 as one of our tagged Magnificent Frigatebirds in the northern Gulf of Mexico off Citrus County, Florida, traveled very rapidly on winds generated by Hurricane Hermine to take refuge well inland in southern Georgia. We are eager to see how this same bird responded to Hurricane Irma.

Of all the birds we are presently tracking, we are most concerned about seven White-crowned Pigeons we tagged with satellite transmitters on their breeding ranges over the last three years for a range-wide study of this species of conservation concern. Two confronted Irma’s 180 mile per hour winds in Puerto Rico, two from Florida encountered the hurricane in northern Cuba, and two more had similar challenges in Jamaica and the Bahamas. The last remained in Florida. We will know soon how these birds have fared.

Just as Hurricane Irma began developing last week, we were in the process of placing small VHF transmitters (tracked by hand in real time) on 12 White-crowned Pigeons in South Florida and Keys. One purpose of this study is to link the most significant mangrove-island breeding colonies of these birds with their specific hardwood-hammock foraging destinations, thereby enabling wildlife managers to prioritize protection of the most important patches of this rapidly disappearing hardwood forest. Because these transmitters cannot be tracked remotely, the fates of these birds could remain a mystery for some time after Irma’s passage.

We hope you and yours safely endured Hurricane Irma, and that you will join us in hoping that as many birds as possible have done the same.

Finally, we are very grateful for all the generous support we have received from organizations, foundations, private individuals, and government agencies to make ARCI’s challenging and important telemetry research possible. They include: Sanibel-Captive Audubon Society; International Osprey Foundation; Felburn Foundation; St. Petersburg Audubon Society; Venice Audubon Society; The Florida Aquarium; West Volusia Audubon Society; Seminole County Audubon Society; Sarasota County Audubon Society; Bailey Wildlife Foundation; Quest Ecology, Inc., Tortuga Foundation; U. S. Fish and Wildlife Service (USFWS), including the Southeast Region’s Division of Migratory Birds, Florida Panther National Wildlife Refuge, J. N. “Ding” Darling National Wildlife Refuge; Florida Keys National Wildlife Refuge Complex; Ding Darling Wildlife Society; Florida Fish and Wildlife Conservation Commission; Microwave Telemetry, Inc.; Friends of the Palmetto Bluff Conservancy (South Carolina); Palmetto Bluff Conservancy; Friends of the Florida Panther National Wildlife Refuge; Friends and Volunteers of the Florida Keys Refuges; U. S. Geological Survey; North Port Friends of Wildlife; Subaru of Gainesville; Disney Wildlife Conservation Fund; Avian Reconditioning Center; National Fish and Wildlife Foundation; Gulf of Mexico Institute; City of Apopka; Halifax Audubon Society; Oklawaha Audubon Society; Clearwater Audubon Society; Orange Audubon Society; Tampa Bay Raptor Rescue;  and individuals including Judy Samelson, Bill Schwabel, Jim Griffith, Margo McKnight, David Hartgrove, Deborah Green, Janet Marks, Eileen Tramontana, Barbara Walker, Joni Ellis, Tom and Laura Hansen, Barbara Brown, Paula Powell, Bill Todman Jr., Bev and Al Hansen, Fred Lohrer, Gary and Susie Zimmerman, Kathryn Palmore, Joyce King, Gary and Joanne Grunau, Tom Staley, Lucille, Lane, Deb Levine, Tim Harrell, Sandy Selman, Rebecca Grimm, and Alyssa Karnitz.

Moonlit migration on the Gulf Coast of Florida

Our celebrated migratory Reddish Egret, Ding#1, has done it again.  She left the J. N. “Ding” Darling National Wildlife Refuge (NWR) on Sanibel Island, Lee County, Florida, to spend the late summer months on the Nature Coast in Dixie County, Florida, from 2 June through 17 August 2016.  In 2015 she made a similar migration to the same location at the end of May, but only stayed a few weeks.

Comparison of  the 2015 (blue) and 2016 (pink) migration tracks of Ding#1, a satellite-tagged Reddish Egret from Sanibel, Florida that migrates to Dixie County in the late summer months.

Based on her breeding-season movements relative to wading bird nesting colonies in Lee County, we do not think this female nested in the spring of 2016, or at least not successfully. This could be why she spent more time on her Dixie County range in 2016. Her northbound migration was direct and punctuated by only one over-night stop, seaward of Homosassa in Citrus County.  Once at her “winter” destination, she used a single foraging area on the coast of the Big Bend Wildlife Management Area (WMA) in Dixie County, from which she flew five miles offshore each evening to spend the night on a small island.  This pattern continued for 11 weeks.

GPS locations  of Ding#1, a satellite-tagged Reddish Egret from Sanibel, Florida that spent 11 weeks off the coast of Dixie County from early June to mid August, 2016.

On 18 August, just after midnight, Ding#1 started south by the light of the full moon.  This is the only time we’ve ever recorded a Reddish Egret embarking on a long flight at night.  We also were interested in offshore night locations, perhaps on a channel marker or stationary boat, where Ding#1 rested for at least two hours. After resuming her southbound night flight, she took one more rest just before dawn in a tree overhanging a house in a busy subdivision in Largo, Florida.  After sunrise, Ding#1 made a bee line to Pine Island and may have fished there for a few hours before returning to her favorite roost near the Wildlife Drive, on the Ding Darling NWR.  She completed her at least 230 mile southbound trip in less than 24 hours, including rest stops. Very impressive!

2016 migration track of Ding#1, a satellite-tagged Reddish Egret from Sanibel, Florida that spent 11 weeks in Dixie County.  Yellow pins highlight locations on her 24 hour southbound track back to Sanibel.

ARCI and our friends at Ding Darling NWR were not the only ones glad to know that she made it back safely.  Not even a day later, photographer Jim Bennight was on the Wildlife Drive and captured a wonderful greeting ritual between Ding#1 and her mate Ding#2.  It is worth noting that Ding#1 is the only migratory individual among the 14 Reddish Egrets we have tracked by satellite from the lower Florida Keys, Florida’s Big Bend, and on Ding Darling NWR.

Satellite-tagged Reddish Egrets Ding#1 (left) and Ding#2 (right) greeting one another at J.N "Ding" Darling NWR, Sanibel, FL, August, 2016.

Satellite-tagged Reddish Egrets Ding#1 (left) and Ding#2 (right) greeting one another at J.N "Ding" Darling NWR, Sanibel, FL, August, 2016.

Ding#1 and Ding#2 continue to grace the Refuge’s Wildlife Drive.  A few non-tagged birds also have been seen on the Refuge. We continue to track five Reddish Egrets in Lee County, plus the single bird tagged on Big Bend WMA in Dixie County. All of the tagged birds displayed their usual movement patterns during the red tide event that affected Sanibel and area waters in late November. We are monitoring them closely for any changes in behavior. You can keep up with the movements of these now-famous Reddish Egrets at: http://arcinst.org/arci-tracking-studies