2013 Juveniles - All data

3 March 2014

And then there was one. We started the year with eight tags on juveniles from Long Island to New Hampshire. We're now down to one, after we lost Bergen, a New Hampshire young and brother to Artoo, our lone survivor. The only silver lining to this dark cloud is that we got Whit's transmitter back an amazing 10 days or so after we realized he had been killed in a collision with a vehicle of some sort in northern Venezuela See the last update (at the bottom of this page) for details.

So, what happened? We always expect to lose about half the young tagged at some point in their first migration cycle, but we've never lost this many this early. Two birds--Peirce from NE Massachusetts and Pearl from Long Island--were probably killed by Great-horned Owls before they really got started on their migrations. We lost Cap'n Liz and Caleb (both from Martha's Vineyard) out over the open Atlantic. All four of the remaining birds made it across the Caribbean. This was the opposite of what usually happens. Typically, most young survive the much longer (sometimes in excess of 1,000 miles) crossing of the Atlantic than survive the shorter (400-500 miles) crossing of the Caribbean. This year all our birds (adults and juveniles) got across the Caribbean without running into a hurricane.

We don't know what happened to Weber (coastal NH), who ran into some sort of deadly trouble in northern Venezuela. Nor do we have any idea what happened to Bergen. He seemed to be in a safe spot. There was little or no signs of human activity around the area where he settled down.

It is rather ironic that we lost Bergen and not Artoo. Artoo has been wandering all over the Amazon, and it's this sort of behavior that increases the chances that young will be lost just because each foray they make into the unknown is one more chance for them to encounter danger--usually in the form of man. The birds that settle down and don't move are usually safe until they head north. This is the reason that adult mortality on the wintering grounds is so low compared to young.

(Older updates are in chronological order)

31 August

It wasn't long after I tagged the last juveniles of the year, on August 12th, up in New Hampshire (Artoo and Bergen) that our youngsters started moving around. One of the two New Hampshire young from the Lakes Region was the first to move. Artoo, now wearing his dad's PTT, took a short road trip just two days after he was tagged. The next day he took off for real, heading southwest. He's now in Pennsylvania, after crossing much of upstate New York.

Next on the runway was Peirce, a young male from Essex Bay, MA. Peirce headed northwest on the 19th, flew up into Vermont, then crossed New York's Adirondack Mountains before heading down into Pennsylvania, where's he's currently holed up.

Artoo's brother Bergen moved next. Bergen headed south on the 21st, in what looked like full swing migration. He's since settled down for a while on the Delmarva Peninsula, which he's criss-crossing from Chesapeake Bay to the Atlantic shore.

Finally, Peirce's neighbor Whit left his nest in Gloucester, MA, and flew down to Cape Cod. After making it all the way to the "elbow" of the cape at Monomoy, he backtracked and spent some time on Long Pond, just north of Falmouth. Remarkably, this is where Belle has been spending lots of time. There's a really good chance that Belle and Whit may have met there. I'll know when I pull up the data for the last week. He's now in Rhode Island.

The rest of our flock of youngsters are staying close to home.

Most young that we've tagged over the years have started migrating in the first two weeks of September, so I expect things to get really busy here at Map Central soon!

7 September

A cold front has moved into the northeast, and surprsingly the only bird who was inspired to get a move on was Weber, a bird we tagged on the NH coast in early August. (We're not sure of Weber's sex. The measurements were borderline, so I'm sticking with male while my colleague on the New Hampshire project is calling Weber a 'she.') Weber had not left the marsh where we tagged him since we trapped him, so it was a surprise to see him go.

13 September

Weber (NH coast) continues to move south, while stay-at-home Pearl just began her migration from her nest on Long Island's North Fork. The birds that left home early (Artoo, Bergen, Peirce, and Whit) had all settled down for a while. This is not unusual for juveniles and begs the question were they really migrating, or do we call this pre-migration dispersal? It looks like Peirce is on the move, but there's a lot of zig-zagging going on. He's not in full migration mode yet, I think.

18 September

Weber (NH coastal marshes) is the only youngster on the move. He made it to Florida in 10 non-stop days of migration. No speed records set--just slow and steady. Whit (North Shore, MA) is stuck in Rhode Island, fishing Nelson Pond (right behind Second Beach) in Newport. Artoo (NH) and Peirce (North Shore MA) are chillin' in the Pennsylvania mountains, Bergen (NH) seems to like what he's finding in a fish impoundment on Poplar Island--an island southeast of Baltimore being restored with dredge sand from the Chesapeake.

On Martha's Vineyard, Captain Liz declared her independence long ago. She rarely goes to the nest any more. She's camped out mostly at Edgartown Great Pond. I'm worried about her brother, Caleb, who doesn't seem to have ever gone out of eyesight of his nest. That was true of Weber as well, and he's now in FL, so I probably shouldn't worry about him.

On the other hand, sadly we lost the signal from Pearl (Long Island, NY). It might be a radio malfunction, but probably means something happened to her. I have a good signal from her at midnight on the 13th, so we may be able to recover the transmitter.

20 September

Weber (NH coastal marshes) continues to lead the charge of the youngsters. He's now safely in Cuba.

On Martha's Vineyard, Cap'n Liz declared her independence long ago. She rarely goes to the nest any more. Now she gets the "Wrong-way Corrigan" award of the year. She flew east to Nantucket and then north up to Cape Cod!

I was talking to Dick Jennings yesterday about how we were both worried about Cap'n Liz's brother Caleb, who it appeared hadn't left sight of his nest since we tagged him. Two hours later I checked his data and discovered that he was in the Bahamas, apparently hitching a ride on a boat, after making a non-stop, over the open Atlantic flight of 1,093 miles in 31 hours.

On the other hand, sadly we lost the signal from Pearl (Long Island, NY). Her signals for 2 days were not moving, so it's pretty certain she died. The optimists can hope that she somehow got her transmitter off, but thaty's unlikely. I always suspect Great-horned Owls when one of our birds roosts in a woodlot and doesn't come out alive. A two-hour search didn't find her or the transmitter, so she might have been dragged off by a raccoon or some other scavenger.

September 30

Getting the bad news out of the way first, we've lost 3 of the 8 juveniles we tagged this summer. We usually lose about half our tagged birds in their first year (this is pretty much normal attrition for any young wildlife), but we don't usually lose them this early in the migration cycle.

Caleb (male from Martha's Vineyard) as far as we could tell never left sight of his nest until he started migrating on September 17th. He tried the long overwater crossing from the Vineyard to the Bahamas and was lost at sea. He had flown about 1,080 miles in roughly 32 hours before he went down. Frustratingly, he was about 50 miles from the safety of the Bahamas when we lost him.

Pearl (Long Island) left her nest area on the 9th of September and settled down in a wooded park near Center Moriches. Her transmitter stopped moving a couple of days later. The search crew that went looking for her saw a Great-horned Owl in the woods. Circumstantial evidence, but I suspect that's what happened to her.

The story for Peirce (North Shore, MA) is about identical, except Peirce left home way back on August 20th, and had been hanging around the mountains of Pennsylvania for almost a month before his signal was lost--in a big woods.

OK, enough bad news, already! Weber was a real stay-at-home. He (or maybe she) never left the marsh where he was born in coastal New Hampshire until the day he started migrating on September 6th. 22 days later he was on the Guajira Peninsula--the first of the "Class of 2013" to cross the Caribbean.

Peirce's neighbor Whit left home on the 24th of August, took a spin out to the "elbow" of Cape Cod at Chatham and then flew west until he got to Newport, RI, where he has been ever since.

Caleb's sister Captain Liz left home early and was on her own by late August. She didn't go far (only a few miles over to Edgartown Great Pond), but she was independent. She didn't go back home for several weeks. When she did move, she decided to go against the flow. Kids these days! Instead of heading southwest, she went east to Nantucket and then north to Cape Cod. She's settled down on some ponds in Chatham and is waiting for who knows what to start migrating.

Our sibling juveniles Artoo (now wearing his Daddy's transmitter) and Bergen both left home pretty early (August 15th and 21st respectively). Artoo wandered around the Pennsylvania mountains going from one river to the next. Bergen got down to Chesapeake Bay and got into some saltwater fishing just east of Annapolis. He was probably eating lots of menhaden. They were 175 miles (280 km) apart as they both "staged" for migration--fattening up for the big push south. Artoo got going on the 20th of September. Bergen started on the 23rd. They practically ran into each other on the Delmarva Peninsula. At 12:30 on the 23rd, they were just a bit more than a half mile apart! If either of them happened to look over his shoulder, he would have seen his brother. Pretty amazing.

7 October

We lost another juvenile. Weber (Coastal NH) made it into Venezuela and last signaled on 1 October. No way to know what happened to him. He was in an area that doesn't appear to have a lot of human activity, so we can't point to shooting as the probable cause of death, but it's always a possibility, if not a probability. (Names in pink are birds that have stopped signaling.)

I spent a couple of hours looking for Pearl in a woodlot not far from her nest on eastern Long Island. Half of the search area was a nasty bull-briar patch (for which I was not properly dressed!). Couldn't find a trace of her--not even a feather, much less her transmitter. There's always a chance that the transmitter will get moved so that the solar panel is facing up and recharges the battery. Should that happen (it has with other birds in the past), we'll get the transmitter back. A Great-horned Owl was spotted in the woods right where we last got signals, so that's our most likely explanation of what happened to Pearl, and is likely what happened to Peirce (Whit's neighbor in MA) in the mountains of eastern Pennsylvania.

Our New Hampshire brothers Artoo and Bergen continue their lazy, and surprisingly synchronized migrations. Whit (North shore, MA) and Captain Liz (Martha's Vineyard) have both settled down (Newport RI, and Cape Cod, respectively) and haven't started migrating yet. This isn't unheard of. We've had juveniles start migrating as late as mid-November.

14 October - Strange Tracks!

Cap'n Liz left us with a cliff-hanger on the 10th. She was out over the Atlantic, southwest of Bermuda, when we got our last signal for her. This track is out there, but Belle, a juvenile tagged in 2010 had gone even further out to sea on her first trip south, and she's still with us, so I thought Cap'n Liz would make it.

Yesterday, when she checked in again, we saw that she was still over the Atlantic, and close to where we last heard from her, so I immediately assumed she had died and was drifting in the open sea.

Well, rumors of her demise were apparently exagerated. When I looked more closely at the data, I can tell that she's still alive and is now riding on a boat or ship of some sort.

 

 

 

The next map shows her changing course at noon on the 10th. Her 1 PM location is almost northeast of her noon fix, and then she heads south again. Between 4 and 5 PM, her locations are less than a mile apart. One very important thing to keep in mind while looking at these maps is that we only know where she was on the hour, so the lines connecting locations do not necessarily reflect her flight path, so we don't know what she did in that hour. We do know that between 5 and 7 PM, she was flying exactly back towards where she'd been 5 hours before. Then between 7 and 8 PM she turned northeast. Then her GPS unit shut down for the night.

Her next fix (at midnight) was 96 miles north. She was moving almost 25 mph during those 4 hours, which is average speed for an Osprey out over open water.

Then things change. Between midnight and 9 AM on the 11th, she moved only 27 miles.

Now things get really weird! This very regular pattern tells me she is not dead and floating. If she were just floating, there would be some degree of randomness to her path. This track is anything but random. She's either on a fishing boat, or, what seems more likely, a research vessel that is doing some sort of transects out over the open Atlantic.

That's not to say that I'm not worried. I doubt she'll make it. She's been 5 days without feeding, unless she's able to catch something off the ship where she is now. There is a published account of an Osprey riding on a fishing boat 600 miles off the coast of Ecuador that would fly out over the Pacific, catch a fish, and bring it back to the ship to eat. That bird rode on the ship for several days. Maybe Liz is doing that. Remember, however, that she can only catch fish in the top meter of the water column, and there aren't a whole lot of possibilities along those lines.

She's had enough time to rest, so she simply may be too hungry to carry on. I'm trying to track down what research vessels are out there.

Our other surviving birds seem to be doing OK. Bergen (NH) made it across the Caribbean and is in Colombia. His brother, Artoo is in the D.R., which always makes us nervous. Whit (Gloucester, MA) is out over open water between North Carolina and Florida. He should be OK.

I spent some time looking for Peirce (Essex Bay, MA) in the woodlot where we last got signals from him. Couldn't find a trace, which isn't really surprising. It was a bit odd how we lost track of him so suddenly. Usually if a bird is killed by a predator, we'll get a signal for days or at least hours. His body may have been dragged down a burrow or something like that, which would explain the sudden cessation of signals.

24 October - Sad news

Cap'n Liz did not make it. She sure tried, hanging on for at least a week out over the open water. She made it that long thanks to her finding the Research Vessel Atlantic Explorer out of Bermuda. The AE was doing deep water column sampling when Liz, probably exhausted from fighting strong winds, found refuge. For three days she was on the ship. The real captain of the vessel, John O'keefe, reports that they saw her eat at least one fish in the rigging. She was hunting for flying fish off the bow wake. Had Liz stayed with the ship for a couple more days, she would be safe in Bermuda now.

Birds labeled in green in the map above have stopped signalling and are dead or presumably so.

Our New Hampshire brothers Artoo and Bergen are safely across the Caribbean. Artoo is further south than we see in this map. Bergen seems to have settled down for a while in Colombia.

Our remaining juvenile Whit (Gloucester, MA) is now in Hispaniola. We hope he makes the jump to South America soon--it's not safe for Ospreys in the Dominican Republic, where Ospreys are shot with some frequency (all four of our juveniles that tried to winter there were shot).

17 November - Juveniles have settled down

The three surviving juveniles tagged this summer have now settled down, apparently, for the winter. We expect them to move around a bit still. We really hope Whit leaves the D.R., where all four of the juveniles we tagged in previous years that tried to overwinter in the D.R. were shot. (As we'll see in the next update, it was more than a bit premature to label Whit's and Artoo's locations their winter ranges.)

 

 

 

9 February 2014

Not long after my last update, when I reported all three of our juveniles settled down but that I expected we'd see some movement, two birds did indeed pull up stakes and go exploring.

Whit, a juvenile from the coast north of Boston, was making us very nervous as it appeared that he was going to try to spend the winter and following year in the Dominican Republic. Of the four young who settled down in the D.R., all four were shot. Dominicans, it turns out, are not good raptor ecologists. They shoot Ospreys because they think the Ospreys will eat their chickens.

We were thus relieved when, on Dec. 13th, he took off and crossed the Caribbean. This is the latest any bird has made the crossing to South America.

Whit had a short, but interesting stay on Aruba. He arrived on the 14th and then it spent a half a day trying to find a way off the island without going back out over open water. He first flew straight across the island and headed out over the water, but decided to follow the island southeast to see if he could make some progress staying over land. He got to the tip of the island and found no way out without crossing water. So then he turned around and tried the other direction. It didn't take him long to find the other end of the island. He was probably looking for a place to fish as he moved northwest because the island is only 18 miles (30 km) long, and he took 4 hours to cross the island. He spent the night of the 14th near the western end of the island and then finally left the island just before 2PM on the 15th, making the short (16 mi/27 km) crossing to Venezuela in probably less than an hour.

He made it to Venezuela and settled down at the mouth of the Gulf of Coro, just south of Punta Cardon on the Paraguana Peninsula.

He stayed there until the 27th of January, when he decided to explore.

 

 

 

 

 

 

 

This is a classic example of why juveniles have such a higher mortality rate than adults. Adults return to a spot that has proven to be safe over the years and just stay there until it is time to head north. Juveniles, like Whit, despite finding a place that is obviously productive--Whit was on the beach at the mouth of the Gulf of Coro for six weeks--apparently have an urge to explore. Obviously, this may help them find an even better fishing hole than the one they were in, but it also exposes them to danger.

So everything was fine until Whit decided to explore north of the beach where he had set up temporary residence on the 27th of January. He flew up towards the town of Punto Fijo and was killed crossing a highway that is right next to a large body of water.

Most of the time we can't tell what happened to birds when they stop moving. This is not one of those cases. When I downloaded data on 9 Feb, I saw that something was wrong with Whit's signals. I zoomed in and found that all the signals were coming from one spot, right by the side of a highway. So much for my relief when he left the D.R. We lost a bird in Long Island in very similar conditions--a busy road right by a big shallow body of water. An Osprey coming out of the water with a fish near the road is in great danger. Ospreys are never very maneuverable, and much less so when carrying a fish, so crossing a busy highway is very risky business.

I sent a message out over a couple of listservs used by Neotropical ornithologists and amazingly within an hour and a half received an email from Gregory Flores, a collaborator with the Fundación Científica ARA MACAO, who was on the ground in Punto Fijo and ready to help out. About an hour later, Gregory emailed from the site of the accident that he could not find the bird. We got another signal the next morning with a single fix at the same spot. Gregory went back out and found Whit's body. I believe it was less than 24 hours after I posted my message on the listservs! The transmitter seems to be working fine, so we'll get to redeploy it this summer. Muchisimas gracias Gregory!

Artoo, a juvenile from New Hampshire, had, quite remarkably, settled down right next to (about 5-10 miles from) Donovan (an adult male whose nest is just 20 miles or so from Artoo's) in the llanos of Venezuela.

On 22 January he got up and started a strong move south again. This is really unusual. More typically, a young that starts moving at this stage will wind up looping back to where it started from--or at least close to it. It certainly looks like Artoo has decided to look for a new fishing hole and doesn't seem interested in going back to Venezuela. This may have something to do with the seasonality of the Venezuelan wetlands. So, now, as if settling down next to his neighbor for a couple of months in Venezuela was not enough of a coincidence, Artoo is now on the Amazon River, only 100 miles from the spot where his brother, Bergen, has been killing time (and fish) since . This is too much!

The move south was, measuring from each night's roost to the next, 905 mi (1,456 km). So he was moving at a rather leisurely pace of about 100 m/d, on a fly some, fish some routine.