Tuesday, November 10, 2015

Winter Death of PearlMS

PearlMS, tagged by Dr. Jennifer Coulson in 2011 near the East Pearl River in Mississippi, spent most of the 2015 North American breeding season in his previous nesting neighborhood along the West Hobolochitto River near Picaynue, Mississippi. It is not always easy to determine whether a male is nesting, though on several occasions, data showed PearlMS roosting during the day in one particular location – a behavioral pattern that suggests incubation shifts.  Jennifer and her husband, Tom, searched the daytime roost locations, wading through the dark water and mud typical of this lowland forest habitat. They did not find a nest, “only lots of mosquitoes,” and concluded that 2015 was not a breeding year for PearlMS.

Southbound migration and last known location of PearlMS

PearlMS left his summer range on 12 August 2015, taking the western circum-Gulf route as opposed to the trans-Gulf route. At the end of the first day, he overnighted at a roost along the Atchafalaya River, then continued overland through Texas and Mexico, keeping within eyesight of the coast except when crossing the Texas/Mexico border, where he flew 80 miles inland around Reynosa.  On 22 August he passed near the famous River of Raptors migration station near Veracruz, Mexico, but was probably a little too far west to be among the counted!  He followed the contours of Central America and in mid-September reached the lush Pacific forests of the western Colombian Andes. PearlMS moved southwest along the range and slowed some, gaining energy required to traverse the high mountain peaks. Having crossed safely, he spent a few days along the Caqueta River in Colombia, then continued through northeastern Peru into the state of Amazonas, Brazil.  Here, where forested rivers provide ample food for migrating kites, PearlMS slowed again to take advantage of the abundant prey.  

On 13 October 2015, only days from reaching his wintering grounds in southern Rondônia, Brazil, PearlMS’s transmitter went quiet. Unfortunately, the most likely explanation is that he is dead. Dr. Coulson has engaged the help of local scientists, hoping they can access the location of the bird’s last signal to look for any evidence. His last transmission came from a remote area of mixed forest and pasture within a very large farm near a dam, the Saldanha Small Hydroelectric Project on the Saldanha River in the municipality of Alta Floresta D’Oeste in Rondônia, Brazil. Although the biologists have not yet gained access to the area, they intend to persist, hopeful they may find some useful clues.

Tuesday, November 3, 2015

Settling into an Austral Summer

Yesterday's tracking data shows that almost all nine satellite-tagged Swallow-tailed Kites are settled into their South American summer ranges.
Locations of nine satellite-tagged Swallow-tailed Kites.

All but one bird is in southwestern Brazil; Gulf Hammock has returned to Santa Cruz, Bolivia, for the 4th year in a row.

Three kites, Day, Strong River, and Bullfrog, are in the State of Mato Grosso, Brazil, within 100 miles of the Bolivian border.

The four kites in Mato Grosso do Sul, include three return visitors: Palmetto (4th year), Pace and MIA (3rd year), plus newly-tagged, Lacombe. Lacombe is the southernmost kite, nearing the Parana border.

Sadly, we report that PearlMS has not made it to his wintering grounds this year. His signal was lost on 13 October while passing through the state of Rondonia. There are several reasons why we might stop receiving transmissions from a bird we are tracking: a dead storage battery, premature transmitter failure, harness failure, a broken antenna, or mortality. The batteries in these solar-powered transmitters last over five years, and we have never recovered a Swallow-tailed Kite’s transmitter with evidence of harness failure or a damaged antenna. Complete transmitter failure has been extremely rare for these sophisticated devices and we have not confirmed one such case in the last 15 years. 

With the guidance of Dr. Jennifer Coulson, a small group of local scientists has tried to reach the last known location of PearlMS, but they have not had luck accessing this remote area of mixed forest and pasture within a large farm near a hydroelectric dam. PearlMS has transmitted since 2011 and in that time has sent us well over 50,000 miles of tracking data. We will share more of the story of PearlMS in our next blog so please stay tuned. 

Every marked bird of every species we have tracked has provided remarkable insights vital to conservation. We remember this each time we accept the privilege of attaching a transmitter to a bird. Sharing their stories with you is one way we can thank them for their contributions. We thank you for following, and for caring about these incredible birds.  

Wednesday, October 7, 2015

Catching up with the kites

It’s been a while so we know you are waiting to hear where the nine satellite-tagged Swallow-tailed Kites are along their migration. All the birds made it safely across or around the Gulf of Mexico, through Central America, over the high elevation mountain passes of the Andes, and are now in South America.

Locations of nine satellite-tracked Swallow-tailed Kites. 

All have followed the same migratory path within days of each other. Once in Brazil, Palmetto sped up, took the lead, and is 540 miles ahead of newly tagged Strong River.

Most of the birds are now in the State of Rondonia Brazil – MIA, Day, Bullfrog, and Lacombe. Gulf Hammock is just across the border in Bolivia.

Another 560 miles northwest, PearlMS is in the state of Amazonas, Brazil. Last is Pace, who left Florida on 2 September 2015. Pace is in northeastern Ecuador, 470 miles from PearlMS.

Soon these birds will settle into winter ranges where they will feast on a variety of insects over forests and fields in Brazil and Bolivia. We look forward to learning where the three newest tagged Kites (Lacombe, Strong River and Bullfrog) will spend their winter.

Wednesday, September 2, 2015

Two ways not to fly over the Gulf of Mexico

Our colleague and collaborator, Dr. Jennifer Coulson of Louisiana’s Orleans Audubon Society, tagged two adult Swallow-tailed Kites at the close of the 2015 nesting season. The following account describes the start of their southbound migration. 

During either their spring or fall migrations, Swallow-tailed Kites from the western subpopulation (Alabama, Mississippi, and Louisiana) may fly south directly across the Gulf of Mexico, or they may head west and travel entirely overland, following the Gulf coastline through Louisiana, Texas, and Mexico. This year, both tagged birds from the western subpopulation circumnavigated the Gulf, but one surprised us by taking an easterly track. 

Jennifer and Tom Coulson prepare to
release Strong River. © Jennifer Coulson
Strong River, newly-tagged near his nest in central Mississippi, left his summer range quite early for a bird west of the Florida Panhandle. After departing his breeding territory, he headed southwest to a known gathering area on the Sabine River, along the Louisiana–Texas border. He spent some time there, probably foraging daily with other kites and fattening up on insects, before moving southward through Texas. By 1 August, he had crossed the Mexican border, then spent the next eight days continuing south along the coastal plain within 20 miles of the western shore of the Gulf of Mexico. Strong River slowed down once he reached Guatemala and Belize. Perhaps he began encountering large numbers of Swallow-tailed Kites that had migrated through Florida and across the Gulf of Mexico, making landfall just to the north and resting after their 400+ mile over-water flight. As we know from years of satellite tracking and Gina Kent’s Masters’ research, this region in southeastern Mexico and northeastern Central American is the most vitally important stop-over area along the U.S. population’s 5,000 mile southbound migration route.

Strong River circumnavigates the Gulf to the west, typical for a bird of the western subpopulation. 

Lacombe. © Jennifer Coulson
Adult male Swallow-tailed Kite Lacombe, tagged by Jennifer in southeastern Louisiana, surprised us all by taking an eastern route through the Florida Panhandle and then turning south through the Florida peninsula. He spent one night in a known roost in Citrus County, Florida, then the next near another roost in the Corkscrew Swamp in Collier County before sailing off the southern shore of remote Cape Sable (the southern tip of the Everglades and Florida) late in the afternoon of 10 August. Lacombe passed over the Florida Keys that night and headed west past the Dry Tortugas to begin his 400-mile crossing of the Yucatan Channel. We have learned that the trans-Gulf flights for most tagged kites begin in the afternoon, perhaps giving the birds the advantage of cooler temperatures and less water loss while flying through the night. Lacombe reached the northern tip of the Yucatan Peninsula 42 hours later and settled in not far south, probably resting and regaining weight by feeding over the expansive tropical forest and scattered Mayan temples west of Tulum, Quintana Roo, Mexico. 

Lacombe, although tagged in Louisiana, takes a route typical for birds of the eastern sub-population.

Thanks to Jennifer Coulson for raising the necessary funds and safely capturing and tagging these birds just before they left the country. We are grateful for her contributions to the Swallow-tailed Kite tracking study over the years.

Thursday, August 27, 2015

Bullfrog and MIA set forth

Movements of MIA and Bullfrog from 20 July - 17 August 2015. 

We’ve been watching closely as our most recently-tagged Swallow-tailed Kite, Bullfrog, began his first migration tracked by satellite. From the west side of Florida near Tampa, where he was tagged, Bullfrog settled into Glades and then Hendry counties, Florida (west of Lake Okeechobee), for a total of 23 days, preparing for migration by foraging out each day from one of the largest pre-migration night roosts we monitor as part of our annual population surveys. On 9 August, he spent the night on the southern shore of Cape Sable before migrating to Cuba. He passed quickly south across the country to spend the next night on the southern coast south of Havana. The next day, Bullfrog followed Cuba’s southern coast west off the tip of Guanahacabibes and arrived on the Yucatan Peninsula on 12 August. Unlike Palmetto, he continued southward over land without stopping to rest, passing through Belize and Honduras before reaching Nicaragua.

1) Gina Kent of ARCI sets a mist net. 2) The serial number from the transmitter is recorded on a data sheet. 3) Bullfrog is ready for release; the antenna of the transmitter is visible at the bird's back.  [Photos: Allison Miller]

MIA left his nesting home range south of Miami on 8 August, just a day before Bullfrog left Cape Sable, Florida, for Cuba. His southwesterly path was nearly identical to that of Bullfrog, with a night on the southern shore of Cuba and a day over the Gulf of Mexico before arriving near Cancun on Mexico’s Yucatan Peninsula in the early morning hours of 10 August. MIA moved slowly through the Peninsula for the next three days but is now in Nicaragua, 100 miles ahead of Bullfrog.

Wednesday, August 19, 2015

Tracking Palmetto

Palmetto, an adult female Swallow-tailed Kite, was tagged in the summer of 2011 In Palmetto Bluff, in southeastern South Carolina, where she has nested ever since. She is now on her 4th southbound migration tracked by a satellite transmitter that provides highly accurate GPS fixes. 
Palmetto begins her southbound migration. 
Each year, she has used a similar area along the Altamaha River in Georgia, where she gathers with other kites to feed over crop and fallow fields as preparation for her impending long-distance migration of at least 5,000 miles. 

This year, Palmetto left the Altamaha River on 30 July and started moving south at a steady pace. She spent four nights in a pre-migration communal roost in Citrus County, Florida, and another night in the Corkscrew Swamp of Collier County, Florida. These two consistently-used roosts are part of 12 such sites that ARCI has been monitoring annually for many years as part of our efforts to track national population trends by conducting synchronized aerial-photo surveys. We have discovered that these systematic surveys in Florida account for 90% of the Swallow-tailed Kites counted range-wide during the peak of their migration departures at the end of each summer. 

Palmetto reached the Florida Keys after dark on 5 August and spent one more night in the United States before heading to Cuba. After a full day over the Florida Straits, she over-nighted on the Guanahacabibes Peninsula of extreme western Cuba before continuing to Belize – a 400 mile flight entirely over water, typical for Swallow-tailed Kites breeding in the United States but extremely rare for a raptor. Palmetto is now exhibiting true stopover behavior in Belize for the last four days, no doubt resting and feeding before continuing the long journey southward to her winter range.

Friday, August 7, 2015

Some surprises as the first Swallow-tailed Kites of the 2015 breeding season fly south

Although we are never sure which of our satellite/GPS-tracked Swallow-tailed Kites will leave the U. S. first on their southbound migration, one of the trends has been for birds nesting the farthest south, such as MIA, to leave the soonest; and for those nesting along the northern Gulf coast to depart later. This year Day, a female tagged in 2011 in Daytona Beach, Florida, was the first to go.  
Day, a Swallow-tailed Kite tagged in Daytona, Florida, is the first tracked bird to 
depart the U.S. for the 2015 fall migration. 
After nesting, she moved into a large communal roost in Volusia County, east-central Florida, where she remained for 24 days before starting south on 25 July.  Day spent a night in the ranchlands of Osceola County, Florida, then another three nights in the largest of the known night roosts just west of Lake Okeechobee.  
Day's plumage is inspected for parasites and molt just prior to release 
in Daytona Beach, Florida. 
Her final night in Florida was on Cape Sable, the tip of Everglades National Park at the southern extreme of the Florida peninsula.  At daybreak on 30 July, she slipped across Florida Bay, the Florida Keys, and out over the Florida Straits on her way to Cuba.  Day was over water for 14 hours before reaching the islands northern shore and rested only a few hours before continuing westward for the length of the Guanahacabibes Peninsula and out over the Yucatan Chanel to the Yucatan Peninsula.  We will see if she makes a lengthy stopover here, which many kites do, before resuming her long southbound migration entirely over land.
Locations and movements of nine GPS/Satellite-tracked Swallow-tailed Kites 
as the 2015 southbound migration commences. 
The second bird to leave the U.S. was Strong River, which our collaborator, Dr. Jennifer Coulson, tagged late in the nesting season in Mississippi.  This is the first time that a kite tagged west of the Florida Panhandle began its southbound migration so early. More on Strong River’s trip in our next blog.

MIA, Pace, Lacombe, PearlMS,
and Gulf Hammock are still in their same locations described in our previous blog.

The Swallow-tailed Kites to watch are Bullfrog, still feeding and roosting south of Lake Okeechobee in Hendry county Florida; and Palmetto of South Carolina. Palmetto recently left her pre-migration staging area on Georgia’s Altamaha River and has made her way south to Sumter County in west-central Florida.

You can help ARCI continue to acquire tracking data and share the stories of these birds lives on this blog by becoming a Keep on Trackin' sponsor. A gift of just $5/month buys two weeks of satellite data each year. Learn more on our Keep on Trackin' program page