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3 Dec 2011: North Fork Bob returned back, safe
and sound at his winter home in the highlands of
the Guianan Shield in southern Venezuela and
then turned around and moved back north.
This is a typical route for an adult. When the wind is
out of the west, they tend to go down the east
coast to the Outer Banks of North Carolina. From
there, they head out over the Georgia Bight for
a roughly 500 mi. trip to Florida.
After a day in the Everglades, Bob moved on to Cuba,
where he spent a week making us very nervous by
hanging around a fish farm.
He's since moved on and is now safely
across the Caribbean in Colombia. He hit the
coast 350 mi (560 km) west of where he did last
year and worked his way east and then south towards
home.
He made one aborted trip up into the highlands. Best
guess is that he ran into bad weather at high
elevations. He retreated 193 mi (310 km) to a
good fishing spot. After another week or so
there, he took 5 days to get home.
Scroll down for all his movement this year, or...
Skip to the start of
fall migration. |
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Spring Migration:
20 Mar-1 Apr 2011:
North Fork Bob is most of
the way home, probably about 4 days left, if the
weather holds for him the whole way.
(Haven't added new detailed maps yet--coming soon) |
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1-31 Jan 2011. Bob has obviously landed in a
very fishy spot. Most of the points on this map
are no more than a kilometer (0.6 miles) apart!
That is is tightest cluster of satellite fixes
I've ever seen. Tongue fully in beak, I wonder
how he's getting enough exercise to be ready for
the trip north, which should begin in the next 3
weeks or so. |
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1-28 Feb 2011. Bob has been fishing a bit
farther from his winter headquarters this month,
going as far as 7 miles (11 km). This is a bit
more typical of a wintering adult. The tiny
cluster of points marking his satellite fixes
over the past couple of months was unusual. |
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1-21 Mar 2011. Bob is finally heading home.
He's off to a late start--the first birds
started arriving in southern New England last
week. He's off to a good start--350 mi (560 km)
in the first two days. Assuming he follows the
usual route through Hispaniola, Cuba, and then
up the east coast, he has about 2,740 mi (4,410
km) to go. In theory, with ideal conditions, he
could make it in two weeks. |
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21-24 Mar 2011. The tracks of both Bob (red)
and Sr. Bones (orange) provide great
confirmation of the generalization that Ospreys
use a couple of simple "rules" in picking their
migration routes--in the spring, head more or
less north and stay over land as long as
possible. This simple migration algorithm got
Sr. Bones to the Guajira Peninsula (the
northernmost point of land in the continent) and
Bob to the next northernmost point of land
across the Gulf of Venezuela. |
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24-27 Mar 2011. Bob is a bird on a mission.
He spent less than 24 hours in Haiti and then
pushed on through Cuba in just over 2 days. Also
on this map are Bob's fall trip south and, in
purple, Sr. Bones' track this spring. There's a
bit of randomness to trips in both directions,
but often geographical features (rivers,
coastlines, mountains) will funnel birds along
similar paths. I'm going to check with my Cuban
colleague, Freddy Santana, to see if there's a
reason that Bob and Bones took the same route
through northeastern Cuba. |
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27-30 Mar 2011. Always good to see our birds
make it through Cuba without stopping at a fish
farm!
Bob took care of Florida in just a couple of days. |
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30-31 Mar 2011. Bob found his way to the
Florida coast in the afternoon of the 30th and
roosted southeast of Jacksonville.
The tracks of Sanford (green) and Sr. Bones (orange)
show that all three of our adults came through
this area in a five-day period. This would be a
good place to watch Ospreys during both the
spring and fall migrations. The St. Johns River
is a particularly favorite stopover for birds
heading south in the fall. |
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31 Mar-3 Apr 2011. Bob's on a beeline for
home. Yellow track is Sr. Bones heading to
Nantucket and Sanford heading to the Westport
River.
Clear sailing this week. |
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3-6 Apr 2011. Bob arrived on Long Island's
North Fork around 2PM on April 6th. Unlike his
fellow travelers, he went inland of the two bays
(Chesapeake and Delaware). He got stuck in a
really nasty storm on the 5th and waited it out.
(see below!) |
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5 Apr 2011. A remarkable weather front moved
across the whole east coast on the evening of 4
April. Bob hunkered down for the day on a small
pond at a golf course near Coatesville, PA,
northwest of Philly. |
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6 Apr 2011. Bob is home! It took him 18 days
to make the 3,100 mi (5,050 km) trip. |
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1-30 Apr 2011.
Bob did not nest this year. He got back a bit
late, and because we don't have anyone on the
ground to watch the nest, we can't be sure what
happened. It might be that his mate did not
return from her migration (it was a really bad
fall to cross the Caribbean, as we discovered
only too painfully) and there wasn't an
available young female to fill the slot.
So this summer's data will show us the travels of an Osprey
footloose and fancy free. Just biding time
really, until the next migration season, and on
the other side of that, another chance to breed. |
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1-31 May 2011. Bob made a couple of trips
away from his usual neighborhood. He went out
over the Atlantic on May 2nd and again on the
3rd of June (that track shows up here but not
the location marker). |
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1-31 May 2011. A closer look at his
locations close to home during May. |
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1-30 June 2011. More of the same here,
really, with a couple of trips away from his
usual area. The two clusters of locations west
of home are a couple of ponds at the Swan Lakes
Golf Course near the
Calverton air field. |
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1-30 June 2011. Locations around the
(unused) nest in
June. |
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7-14 June 2011. Here's a comparison of
Tucker and Bob's foraging during the second week
in June. Tucker spent a lot of time foraging out
in Long Island Sound. (More comparisons of the
two are on
Tucker's map page.) |
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1-25 July 2011. Bob stayed a little closer to home in
July. Looks like he was doing some fishing in
the sound, but not as much as his late neighbor
Tucker did. At least he didn't range as far off
shore. |
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1-31 July 2011. The action close to home.
Same old same old. |
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25 July - 6 Aug 2011. A bit more time spent
working up the North Fork north of Shelter
Island. Still likes the Swan Lake Golf Course
ponds west of Flanders Bay. I've left the tracks
connecting points out of this map. With the
tracks included, the area between Bob's nest and
the western most locations is pretty much
painted red. This means that almost all the
points to the west are a single visit with a
return to his home base. One might misinterpret
this map as indicating that he flew out to the
west and spent long periods of time there before
returning to the nest. |
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6 Aug - 7 Sep 2011. A very interesting shift
here. Obviously, some fish species has appeared
in Peconic Bay. The fishing has been so good,
that he has completely focused his activity in
this small area around the nest. The next map
compares July and August foraging areas. |
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3 July - 7 Sep 2011. A fascinating shift
here. The red lines without location flags
record Bob's movements from early July through
the 4th of August. From then on, Bob apparently
found the fishing so good in Peconic Bay that he
no longer needed to commute. Everything he
needed was right there in his front yard. |
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6 Aug-7 Sep 2011. Close to the nest, the big
change here is that he's not spending so much
time around the pond just east of Maratooka Pond
(Deep Hole?). |
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8 Sept-2 Oct 2011. Still hunting a lot
in Peconic Bay for most of September. He took
off for points south around 9 AM on Oct. 3rd. |
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3-4 Oct 2011. Bob left Mattituck
around 9 AM on the 3rd and spent the night of at
a little pond near South Brunswick, NJ. On the
4th, he was probably counted by the hawk
watchers at Cape May. He spent the night of the
4th on Chincoteague Island in northern Maryland.
Looks like he skipped Delaware this year! |
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5 Oct 2011. Bob got a very early start to
the day's migration, heading out over open water
from Chincoteague Island around 6AM. He hit the
Outer Banks in North Carolina around 10AM and
probably did some fishing there before pushing
on to Cape Lookout, where he spent the night of
the 5th. |
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5-8 Oct 2011. Bob took off from the
Cape Lookout area around midnight on the 5th.
This is really unusual. We've had lots of birds
migrate at night, but that was always after
taking off during the day and getting stuck out
over the water when the sun went down. I can't
imagine why Bob took off in the middle of the
night. The last fix of the day was at 8PM (the
blue wavy lines) on Oct 6. It would have been
dark by then, but he had only a short way to go
before getting to the Florida coast. He hung
around Jupiter (just north of Palm Beach) until
10AM and then was off to the Everglades and
Florida Bay. |
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7-8 Oct 2011. Bob spent the 8th around
the Everglades and the north shore of Florida
Bay. |
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7-10 Oct 2011. After a day around Florida
Bay, Bob took off for Cuba around 9 AM on the
9th and about 8 hours later arrived on Cuba's
north shore.
On the 10th, migration consisted of about 3 hours'
movement southeast to the vicinity of the tiny
village of Venegas. |
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10-17 Oct 2011. Bob continued his "migration
lite" movement through Cuba. On the 12th he
found a small reservoir has an associated fish
farm, which is making us very nervous! We've
lost too many Ospreys in Cuba at just this kind
of location to feel good about this. |
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12-17 Oct 2011. Bob has settled down at this
small reservoir. Fortunately, for the past 6
days it seems Bob has found all that he needs up
in the stream that feeds the reservoir and
hasn't been dipping his talons into the fish
ponds. Because we only get fixes every hour, we
can't be sure that he hasn't been down to the
ponds, but chances are had he been down there,
we'd have at least one fix near the ponds.
I'll be very happy when he moves on from this spot. |
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18-26 Oct 2011. Bob survived his stay near a
fish farm and started moving again on the 20th.
He kept moving at a modest pace through Cuba and
over to Haiti on the 24th. |
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26-27 Oct 2011. Bob kept right on going and
crossed the Caribbean in 25.5 hours. During that
time, he covered 472 miles (760 km) at an
average speed of 19 mph (30 kph), which suggests
he was probably fighting a bit of a headwind
most of the time.
He clearly had a different wind than he did in the fall
of 2010. He made landfall in S.A. a bit west of
of Dubilla this year 340 miles (548 km) west of
where he arrived back in 2010.
Now we get to watch him navigate back to his wintering
area. |
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28 Oct-4 Nov 2011. Bob rested a bit near the
coast and then moved eastward. On the 29th he
stopped near a large mining operation near
Albania, where he stayed until Nov 5.
We were nervous at this point, as there is a lot of
human activity there, so we were glad to see him
move on, dodging bullets again, both
figuratively and perhaps literally. |
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28 Oct-4 Nov 2011. Bob a week around this
large quarry operation in eastern Colombia. I
don't know if the ponds are fish farms, but they
look like it, and we were plenty nervous. |
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26 Oct-9 Nov 2011. Bob landed in South
America 340 miles (548 km) west of his landfall
in the fall of 2010 and immediately began
working his way back to his wintering area in
the highlands of southern Venezuela. |
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28 Oct-7 Nov 2011. In this map it's easier
to see the topography that Bob is working
around. He hit the Colombian coast just north of
the Sierra Nevada de Santa Marta, the world's
highest coastal mountain range, with peaks up to
nearly 18,000 ft ASL (5,700 m). Too much work to
go over that, so Bob worked due east at the foot
of the range and then got into the Lake
Maracaibo Basin. Once into Venezuela, he worked
his way around Lake Maracaibo and then found the
Cordillera de Merida in his way. He skirted the
foot of this range until finding a pass just
south of Barquisimeto.
Once through the pass, he was out in the Orinoco River
drainage, heading south towards his wintering
spot on the Ventuari River in the western
reaches of the Guianan Shield. |
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8-16 Nov 2011. Bob moved southeast and got
to the foothills of the Guianan Shield on the
16th. He moved upslope a bit and then retreated.
I suspect he ran into some bad weather at the
higher elevation. |
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16 Nov 2011. Bob followed different valleys
going to his wintering area last fall and
heading north in the spring. This year on his
first attempt he didn't make it into the
highlands. He probably ran into bad weather up
at higher elevation and then retreated. |
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17-22 Nov 2011. After abandoning the trip up
into the highlands on the 16th, Bob retreated
193 miles (310 km) to a spot where he spent the
second week of November. |
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9-22 Nov 2011. Here's a more close-up look
at his movement after the aborted trip up the
Guianan Shield. Bob spent 4 days mostly in the
Venezuelan state of Portuguesa. It's hard to say
if the three forays south were real attempts to
get back to his winter home or just fishing
expeditions.
The resolution of the imagery here isn't very good, so
it's hard to tell what the human activity here
is, but it might be some kind of mining.
In any case, on the 22nd, he moved south and four days
later was back on his winter waters up in the
highlands. |
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22-26 Nov 2011. Home at last!
The solid green area is his entire range for last
winter. This is one of the reason's adults have
a higher survival rate than juveniles--the old
birds stay put in a place that has proven to be
safe over previous years, while the young birds
are wandering around the countryside looking for
a really reliable spot. All that movement means
an increased chance of running into danger,
which nowadays is pretty much synonymous with
humans. |
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27 Oct-26 Nov 2011. Here's how Bob worked
his way around the mountains of northern South
America.
In about 4 months, he should turn around and do it
again!
But wait,.... |
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26 Nov-3 Dec 2011. Just when I thought I
could stop making maps for a while, Bob throws
us a curve ball and moves back down out of the
highlands.
This is really unusual. Every adult except one that we
have followed has returned to their winter
waters and stayed put until it was time to head
north.
So, why would Bob have returned to the spot where he
spent 5 months last year and after only 4 days
head back down out of the highlands?
What changed? Hard to imagine the fishing being that
different. Has there been increased human
activity in the area? We can't tell from the
Google Earth images, as they are old. Maybe
another Osprey moved in and has claimed the
territory? There isn't much evidence that
Ospreys are territorial in the wintering areas,
so that's a unlikely explanation, but it is a
possibility.
Stay tuned!
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3-18 Dec 2011. Here's the area where Bob has
settled down after retreating from his highlands
wintering area.
This seems like an unusually dry area for a wintering
Osprey, but in fact he's in the seasonally
flooded llanos, so much of what we see here is
underwater. |
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2 Dec 2011. Backtracking a bit, Bob spent a day in the strange
dune crossed region of the state of Apure. These
dunes are thought to be caused by the Trade
Winds picking up sand from the Orinoco at low
water.
From Wikipedia: A large part of the state of
Apure is constituted by an extensive field of
dunes (occupying some 30,000 km²), which has the
peculiarity of not being a desert climate but a
savannah, with natural grasslands alternating
with corridors of jungle and voluminous rivers
with sand dunes of more than 100 km in length
and 20 m in height. |
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3-18 Dec 2011. Bob has settled down in what
appears to be a remarkably inhospitable habitat
for an Osprey. It seems to be a cattle ranching
region with very little obvious water.
I'm sending out inquiries to our Venezuelan colleagues
to see if they can offer any insights. Maybe
this area has much more water now than it did
when the satellite imagery was captured.
Stay tuned! |
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12-24 Dec 2011. Another week in the llanos
(which were flooded during this time). The area
he covered was 0.69 square miles (1.8 square
km). On the 24th he decided it was time to get
back up into the highlands where he spent all
last winter. |
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24-28 Dec 2011. Bob is back in the
highlands. We can only speculate about why he
got to his winter spot on 26 November and then
turned around 4 days later and retreated to the
llanos. Maybe he left his wallet down there?
After three and a half weeks down in the lowlands, he
abandoned the area in favor of his old, reliable
fishing waters. |