In 2000 I began collaborating with Mark Martell, who was then working with The Raptor Center at the University of Minnesota. At that point, Mark had already put well over a hundred satellite transmitters on Ospreys all over the US and followed their annual migrations from the breeding grounds to wintering areas in Mexico and Central and South America. (Mark now works for the Minnesota Audubon office as their Director of Bird Conservation.)

     Several patterns have been elucidated by Mark's tracking of Ospreys across North America. The Pacific Northwest birds all make a non-stop sprint migration over the western deserts and winter in Mexico and Central America. None of these birds has gone as far as South America.
     East coast birds all go down the east coast, some fairly far inland, some along the coast proper, to the tip of Florida, over to Cuba, and then on to Hispaniola (Haiti and the Dominican Republic). Some winter in the Caribbean, but the majority make the 4-500 mile trip across the Caribbean to Venezuela. From there, they scatter across much of the South American continent, some going as far as the Pantanal in Paraguay and Southwestern Brazil.
     There are some very rare exceptions--two birds we have followed got to Cuba and went west to Central America and then on into South America via the Isthmus of Panama, and one of our 2006 birds went due south from Cuba to Jamaica and on to Panama--a crossing of over 700 mi.
     Birds that we have followed for several migrations tend to be as faithful to their wintering spot in South America as they are to their nesting area up north.
     Males and females take separate vacations, which someone waggishly suggested is the reason they can stay mated for life. The young travel on their own when they head south. They do not follow their parents, but work on pure instinct, apparently following a fairly simple two-line program: Go south and stay over land as long as possible. This gets them to the Keys in Florida, the southeastern tip of Cuba, and many of them to the little peninsula on the south coast of Hispaniola.
     The young remain on their wintering grounds for an extra year, not returning until just before their first "hatchday". They're not going to breed until they're 3 or 4 anyway, so we suspected they may use the extra time to locate a really reliable fishing spot for future migrations, but our growing data set for young birds suggests that they've already settled down well before their "extra" year in the tropics, so it may just be an adaptation to avoid the risks associated with a 3000+ mile trip. 

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SATELLITE TRACKING ON MARTHA'S VINEYARD, RHODE ISLAND, NC, AND DELAWARE.

In our first first year we tagged two birds--a mated pair from the south shore of Martha's Vineyard. "HX," the male (the birds were named for the letters on their colored leg bands), migrated to the delta of the Orinoco River in Venezuela and returned the next spring. His mate died somewhere in Panama in November. (Maps)      In this photo, Mark and Annie Lemenager hold KC and KB, the adult pair we trapped and tagged at Felix Neck in 2001. In addition to the Felix Neck pair, in 2001 we tagged "KD," HX's new mate, and a female in Charlotte, NC. (Maps)      The Charlotte bird wintered in Peru but died crossing the Gulf of Mexico on her spring migration in 2002. KB and KD landed on boats crossing the Caribbean on their southward migration in the fall and disappeared. We don't know what happened to them. HX died on his wintering grounds in Venezuela.

    No new birds were tagged in 2002. KC returned from his wintering area in Venezuela only to find a young male claiming his territory. He was late getting back (he left his wintering grounds a week after the first Ospreys arrived on the Vineyard), so I suspect he may have been an old bird. (Maps)

We followed him through another migration, and in the spring of 2003 he once again was late leaving Venezuela. When he arrived (a week later than the year before), he once again found a bird claiming his territory. This may have been the same male that tried to claim the territory the year before. Whether or not it was, the new male was not to be intimidated and a rather vicious battle ensued. KC was driven, bleeding, from the territory and found dead about two weeks later on the shores of the Lagoon in Vineyard Haven. The good news of this story was that we were able to recover his transmitter and had it refurbished for deployment in 2004. (Maps)

     In 2004 the BBC contacted me and asked if I'd help with a series of documentaries they were planning entitled "Incredible Journeys." They wanted to start with Ospreys and offered to buy 4 transmitters if I would help them with their show. Never one to look a gift horse in the mouth, we put their transmitters on 4 Vineyard Ospreys and the transmitter recovered from KC on a fifth bird. On our first expedition to the Island we tagged an adult female (Elsie) at her nest in Edgartown and an adult male (Bluebeard) near the great clay cliffs of Aqunnah. We then ran out of luck and time and couldn't catch any more adults but still had 3 BBC transmitters to put on birds. So we came back in late July and put the transmitters of 3 young birds, Tasha, Bunga, and Jaws. Tasha and Jaws turned out to be the stars of the BBC's show. Bunga died near New London, CT. (We we were able to find the transmitter and use it in 2005.) Tasha made it to Hispaniola, where she went off the air. I suspect she wound up in a soup pot. Jaws made it to Colombia and settled down in an enormous lagoon, which was nothing short of Osprey heaven. Bluebeard, after an extended stay near the nest taking care of an apparently incompetent offspring, migrated deep into Columbia, almost at the Brazilian border. The documentary (Osprey Oddysey) aired in 2007 on the Animal Planet. (Maps)

    In 2005, Bluebeard returned to his nest in the spring. We tagged a young bird (Homer) on Martha's Vineyard and a young bird (Conanicus) on Conanicut Island in Rhode Island. Conanicus migrated as far as Cuba and decided that that was far enough. (Our first bird to stop in Cuba.) Homer led us on a merry chase, which included migrating through NC three times on the same migration (see his maps for details)! Bluebeard made it all the way into Columbia and was on the home stretch of his migration when he disappeared. Suspiciously, our last signals from him were in an area with extensive human activity. We're quite sure he was shot. Jaws remained on his winter territory throughout 2005, although his transmitter went off the air in November, leading to much anxiety here at Osprey Central. (Maps)

    In 2006, Thanks to the efforts of the staff and Friends of Cape Henlopen State Park, we expanded our project south and tagged three young Ospreys in Delaware. Rhode Island Audubon sponsored another transmitter for a bird in Jamestown, and we put another transmitter on a recent fledgling on Martha's Vineyard. 

     Meanwhile, Jaws was spotted flying north through North Carolina by a colleague in Wilmington in May, several months after I had deactivated his ID with the satellite company, ARGOS. A week after he was spotted, ARGOS contacted me to say that they were receiving intermittent transmissions from him and ask if we wanted his ID reactivated. We did indeed and had remarkable luck with his transmitter turning on exactly when we would have turned it on ourselves, had it been under our control. It came on just as he was crossing Rhode Island and landing on the Vineyard. Then it went off for a while, but came on in August, documenting his return to the very spot in eastern CT where he had spent a month prior to his first migration back in '04. This dovetailed beautifully with our observations of adults that commuted back and forth between freshwater areas in NY or CT and their nesting territories after a nest failure. It appears that some Ospreys have a favorite fishing hole in freshwater areas that they can rely on when the fishing is bad around the nests, and return periodically to the nests, 1-200 miles away to make sure no young upstart gets any ideas about the territory being vacant.

     Jaws' transmitter went off for a while, but came on just as he was leaving FL and documented his trip across the Caribbean and return to the same general area where he spent his first year and a half in South America. 

     While Jaws was doing his first trip north and south, Homer had settled down in Venezuela, and Conanicus spent a year and a half in the Zapata Swamp on the south shore of Cuba.

     The "Class of '06" provided some interesting new data. One of the DE birds made it as far as Savannah, GA, and decided that was far enough. Another headed south over the Atlantic from Bald Head Island, NC,--a route a fair number of birds take on a short-cut to FL, but this bird had a bit too much east in her internal compass and went down at sea about 150 miles from Turks and Cacos Islands in the eastern Bahamas. The third Delaware bird made it to the Amazon, where she is currently waiting out her year-and-a-half on the wintering grounds. 

     The two New England birds did not fare well. The RI bird, Comet, showed us a new route, heading due south from Cuba, passing over Jamaica before crossing the Caribbean the really long way, landing in Panama. From there he headed into South America, where we lost his signal in November. We don't know what happened--it may be a malfunctioning transmitter, or he might have died. Moshup, our lone Vineyard bird tagged in '06 settled down for the winter in the Dominican Republic and was shot in March by hunters who confused him for a Red-tailed Hawk (which the shoot because Red-tails will take chickens, and back-yard chickens are an important protein source for many in the D.R.) We were able to get his transmitter back, as well as the transmitter from the DE bird that was wintering around Savannah. We have no idea why he died, but West Nile Virus is always a suspect with birds of prey. (Maps)

     In 2007 we tagged five more birds--two in Delaware and three on Martha's Vineyard. Three of these transmitters are new, state-of-the-art GPS transmitters, two were the transmitters we recovered from Moshup and Lew. Previous units provided locations that were at best within a hundred yards or so of the bird's true location, often miles off. The new transmitters provide very accurate hourly locations, as well as speed, altitude, and direction of each fix. After only a week's data collection, the results are already surprising! (Maps)

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