Friday, March 23, 2018

March Madness: Four More Gulf Crossings

For many Swallow-tailed Kites, reaching the tip of the Yucatan Peninsula in Mexico means they have entered the home stretch of their northbound migration. One last 500-mile-plus push across the dazzling teal waters of the Gulf of Mexico and they’re back over land, reaching their nesting locations with plenty of juicy, nutritious food available along the way.

But the weather can make or break the trip. Northerly winds pushing down the Gulf of Mexico make the risky, direct route home even more challenging. Instead of riding southerly tailwinds, the kites must struggle upwind. Some end up stalled over open ocean, exhausted.

Luckily, failure was not in the cards for Bogue Falaya, Lacombe, Palmetto, and Sarasota. They all made it safely across the Gulf of Mexico, albeit in unexpected ways.

Bogue Falaya was the first of the four to start crossing the Gulf of Mexico, on 9 March. Strong northerly winds forced him to double back and linger off Mexico’s coast until the evening of 10 March, when he was finally able to resume northward travel. At 4 am on 12 March, Bogue Falaya made landfall in the panhandle of Florida near Carrabelle. He was still in the area as of 20 March.

The last two years, Lacombe was able to fly almost due north from the Yucatan Peninsula to his nesting grounds in Louisiana. But not this year. He left the Yucatan Peninsula on 11 March and was immediately pushed eastward, reaching land near Sarasota, Florida, on 12 March. Ever since, he’s been working his way westward, over land, towards Louisiana.

Palmetto waited until the winds quieted to cross. Leaving on 15 March, she was able to fly due north across the Gulf and reach Panama City, Florida, on 17 March. She cut east to the Florida Panhandle, then turned towards South Carolina just north of Jacksonville, Florida. By 20 March, she had reached her nesting grounds. This seems to be her favored flight path, as she took a very similar route in 2017. Who could quibble with her methods? Since being tagged, Palmetto has survived 7 yearly round-trip migrations – that’s over 70,000 miles. What an amazing feat.

Sarasota left the Yucatan Peninsula on 17 March. Instead of flying the short, direct route back to Sarasota County, Florida, Sarasota slowly drifted northeast for two days and reached Steinhatchee, Florida, on the morning of 19 March. Returning to last year’s nest site will be the next priority.

Sunday, March 18, 2018

First Flights to Florida: GPS-tracked Swallow-tailed Kites return to their breeding grounds

If you live in the Southeast, you may have had the privilege in the last few weeks of spotting a graceful black and white raptor soaring over the treetops. They are starting to settle in to nesting territories and court with display flights. They clutch snakes, anoles, or Spanish moss to attract the right mate to the right tree in the right nesting stand – all to do their best to advance their genes into the next generation of Swallow-tailed Kites. The kites have come a long way, most of them 5,000 miles or more, and some are yet to arrive, but they all are running “on time”. These are things we wouldn’t know without the fantastic tools of satellite and GSM technology, from which we are learning so much about migration timing, routes, roost sites, and habits. We need all this information to conserve this spectacular species.

Here we’ll feature the return of two of Florida’s Swallow-tailed Kites, Babcock and MIA, to their breeding territories after they crossed the often-deadly Gulf of Mexico.

Babcock started north in mid-January. After a 2-week stopover in Amazonas, Brazil, he stuck to a rapid pace through South and Central America. In Honduras he took a short cut, one we see many kites take, across the Gulf of Honduras to northern Belize. After a brief over-night on the Yucatán, Babcock caught a tailwind on the morning of 7 March that enabled him to reach land at Cape Sable, Florida, after 36 hours. He spent a night in the Picayune Strand State Forest near Naples, Florida, then returned to his breeding territory in Charlotte County by 9 March.

MIA perches in a pine.
Photo by Alice Horst 2018.
MIA wintered close to Babcock, in Mato Grosso do Sul, Brazil. They departed their winter ranges within a day of each other, although over 160 miles apart at that point. They took a very similar route northward and were at one time within 3 miles of each other. We’ve had a lag in MIA’s data across the Gulf of Mexico, but have learned from some of our great supporters that he was, in fact, back on his former territory by 8 March. He has been photographed courting and nest building once again. No time wasted!

Monday, March 12, 2018

Movement Update: 26 February 2018

All migrating Swallow-tailed Kites we have tracked since 1996 have crossed the Andes Mountains from east to west in western Colombia before continuing northward. In Columbia, the Andes Mountains consist of three major ridges: the Cordilleras Oriental (eastern), Central, and Occidental (western). On 26 February 2018, MIA and Babcock were over the Cordillera Occidental on their way to Panama.
Bogue Falaya and Lacombe were approaching the Cordillera Oriental in southern Columbia. Wilson and Panther were on the border of Peru and Brazil. Palmetto had surged ahead of Sawgrass, Apopka, and Refuge to join Sarasota in the state of Amazonas, Brazil.

Sawgrass left her wintering grounds on 2 February and was just north of the Bolivian/Brazilian border. Apopka had moved slightly north in the state of Rondônia, Brazil.

Refuge has not sent data in a few weeks. Why does this happen? We use transmitters with two different types of data-delivery methods: one where the data comes to us through satellites; and another that uses the cellular network. Refuge is being tracked with a solar powered GPS/GSM (cellular network) transmitter made by Ecotone Telemetry, Inc., which needs to be within range of a cell-phone tower to upload the data. When a bird is beyond range, the unit stores daily GPS locations until its signal can be picked up by a cellular tower. This is happening right now as the birds are crossing through the great Amazon basin and over the Andes Mountains. Sawgrass, Panther, Sarasota, Babcock, Wilson, and Apopka also are tracked by GPS/GSM transmitters.

MIA, Palmetto, Lacombe, and Bogue Falaya are being tracked by solar powered GPS/satellite transmitters made by Microwave Telemetry, Inc. These units upload data to satellites, always within transmission range, every 2 days, and store GPS locations in the off day while the transmitter recharges, resulting in essentially continuous data delivery.

Tuesday, March 6, 2018

Ready to Return

Before reading on: Be sure to familiarize yourself with the eleven Swallow-tailed Kites we’re tracking in last week’s blog, “New and Familiar Feathers”.

In September 2017, our attention turned to the effects of Hurricane Irma, and reporting the progress of our tagged Swallow-tailed Kites’ southbound migrations fell through the cracks. We’re happy to tell you all eleven individuals safely reached their respective wintering grounds in South America. Nine Swallow-tailed Kites left from the southern tip of Florida to cross the Gulf of Mexico, a familiar route many tagged birds have taken in previous years. Lacombe and Bogue Falaya, both from Louisiana, skipped the ocean option and instead took the less-risky path over land, down the east coast of Texas and Mexico, ultimately rejoining the rest of the southbound birds from the US population.
Southbound-migration paths of ARCI's eleven tagged Swallow-tailed Kites, 2017. 
Environmental and biological triggers tell Swallow-tailed Kites to migrate each season; however, each individual’s itinerary looks slightly different. Babcock crossed the Gulf of Mexico first on 13 July 2017. Two weeks later, Refuge and Panther followed, leaving Florida hours apart. Palmetto, MIA, Lacombe, Sawgrass, Sarasota, Bogue Falaya, and Wilson left throughout August. Last but not least, Apopka jetted south just three days before Hurricane Irma hit Florida on 8 September.

Babcock may have left two weeks earlier, but Lacombe, Palmetto, MIA, Panther, and she reached the State of Mato Grosso do Sul, Brazil, within 5 days of each other in early October. Next came Sawgrass, who leisurely joined the others in mid-November. Sarasota, who was in the State of Amazonas in western Brazil in October, reached Mato Grosso do Sul in January 2018. These seven Swallow-tailed Kites all used the same 700 square-mile patchwork of ranchlands and remnant forests.

Three kites, Apopka, Refuge, and Bogue Falaya, over-wintered in the State of Rondônia, about 800 miles north of the wintering grounds in Mato Grosso do Sul. Here the landscape is a mosaic of farms and forest as well. Speeding through Central America, Bogue Falaya wasted no time in reaching Rondônia in early October. Apopka, who left last and spent a few extra days in Cuba, likely waiting for favorable winds after Hurricane Irma, reached Rondônia in early November. Refuge spent September and October on the northern border of Bolivia and Peru, then moved west to join Apopka and Bogue Falaya in December. Wilson spent October in Rondônia, but moved on to the State of Mato Grosso in November, where he stayed until January.

We waited patiently for the data to suggest the restlessness commonly observed in migratory birds about to make their seasonal moves. On 19 January 2018, MIA was first to move north out of his wintering grounds. MIA began his northbound migration on this exact day in 2017. Palmetto did the same, leaving on 2 February in both 2017 and 2018. Talk about consistency! This is most likely due to the kites’ sensitivity to day length as a way to time their migration departures.

The location of 11 tracked Swallow-tailed Kites as of 5 February 2018.
Lacombe left Louisiana on 21 January, one week earlier than in 2017. Panther left one day later than her 2017 departure on 18 January. According to her latest data, Sawgrass remains on her wintering grounds as of 28 January. We expect her to make a move soon (last year, she started north on 10 Feb).

For the six Swallow-tailed Kites tagged in 2017, this is our first glimpse into the paths they will take on their northbound journeys. We hope all of them have uneventful journeys.