ArcticRaptors.ca Blog

...some don't

2011-12-30T21:04:00.000-07:00

Although early arrival at a breeding cliff can be risky, it has its benefits too...there's usually no objection from other potential breeders, at least for a while. Eventually though there's conflict at some level. Most often disputes are short, vocal and without contact. On occasion though a brouhaha ends in injury or worse.

7|H captured with leg injury in 2005, returned to breed in 2006 (A. Franke)

Territory holder 03 B killed by intruder in 2007 (A. Franke)

Life time reproductive success is real currency here, and where adult investment (see weight loss) in offspring is within reason, eggs and young are closely guarded day and night.

Female falcon threatening an unknown intruder (RECONYX)

The margins are narrow and the investment considerable. All things being equal, adults arrive in late May, lay a full clutch of eggs by the middle of June, hatch their young in mid-July. Rearing a brood of nestlings lasts 'til the last week of August, and fledglings remain near the cliff for another 3 weeks. Birds leave for their wintering territories in the middle of September.

Although short, August nights are cool at 70 degrees north (RECONYX)

Some make it...some don't.

Remains of 8|U and 13 B on nest ledge, fate of 8|W (3rd chick) not known (A. Franke)

Some get a second chance...

August 20, 53 C at 35 days old on her nest ledge near Iglulik, NU.

Barry Robinson banded 53 C (and her 3 siblings) at 27 days of age on August 12, 2011. She weighed 792g. Three months later (November 11), she was recaptured in Mexico by Oscar Diaz. She weighed 920g.

53 C just prior to capture in Mexico, Nov 11 (O. Diaz)

Once in hand, Oscar (a falconer and bander) realized that 53 C had frounce (Trichomoniasis), likely as a result of consuming an infected pigeon or dove. The infection had advanced sufficiently to cause watering and swelling of her eye, and although necrotic lesions were apparent in her mouth, they were still quite small.

53 C immediately after capture in Mexico (O. Diaz)

Oscar treated the infection, and a month later began flying and hunting with 53 C. She hunts at 940g, and will be released in April in time to migrate.

Oscar Diaz with 53 C

It's not often you see a blue banded falconry bird, good to know she is in good hands.

Alastair

It's all in the fat

2011-10-29T13:02:00.003-06:00

Much about bird migration remains a riddle, and the puzzle persists when, for example, landbirds undertake open-water crossings that require hour upon hour of sustained flight despite the availability of seemingly safer terrestrial routes or man-made structures on which to land. In the Gulf of Mexico, there are hundreds of active oil platforms and peregrines are known to use them, leap-frogging from one to next using them to rest, cool off or as place from which to capture prey.

Swordpress map and YouTube video showing rigs 1942-2005

Despite the presence and safety of the platforms, some birds crossing the Gulf of Mexico apparently ignore them. For example, after spending 3 days on the Louisiana Gulf coast, one of our birds (28 E) crossed the Gulf flying 540 miles in 11 hours. She spent that night on the Yucatan Peninsular, then once again made a non-stop flight of 430 miles in 12 hours crossing the Caribbean sea to Honduras where she remained relatively sedentary for the next 36 hours. Then ignoring Nicaragua, Costa Rica and Panama, she again traversed the Caribbean Sea making landfall in Colombia 650 miles and 28 non-stop-hours later.

Between October 19 and 24, she flew more than 1850 miles and crossed 1620 miles of open ocean in 51 hours of sustained flight.

1850 miles and three open water crossings (totaling 1620 miles) in 5 days

Fat reserves are critical to lowering the risks of migration in general and managing the risks of strategies like open water crossings in particular. Fat carries twice the energy compared to the same amount of protein or carbohydrate. So storing fuel as fat is smart - birds can reduce the weight they have to carry despite loading up on their on-board fuel. Smart too, because burning fat produces water - not enough to prevent dehydration, but enough to slow it down. For Arctic-nesting peregrines that lose body mass whilst raising broods of young, getting fat fast could make open-water crossing safer than it appears.

28 E feeding her 3 nestlings

Some Slack

2011-09-26T09:54:00.000-06:00

Biologists welcome any encounter with the animals theystudy, but consider themselves particularly lucky when the same individual isencountered multiple times. The odds ofa re-encounter can be improved by marking animals that reliably return to thesame breeding, stop-over or wintering sites year after year.

Breeding cliffs in Arctic spring (J. Kennedy)

A great deal has been learned aboutperegrines because of their tendency to behave this way. But it takes many years, a lot of birds, hugeresighting effort and persistent people to build individual encounter historiesrepresentative of the peregrines in our study.

Hilde Marie Johansen with marked adult female (A. Anctil)

For example, at Rankin Inlet this spring we captured afemale (banded A|X) that is at minimum 15 or 16 years old. First encountered in adult plumage (likely 3or 4 at that time) in 1999, A|X has been encountered on five other occasionsduring her tenure at Rankin Inlet.

Weknow quite a bit about A|X. Over theyears she’s been paired with several different males at three differentsites. Despite her longevity and abilityto hold a territory, she’s a reproductive dead-end! We have not banded a single nestling at thesites she has occupied – she failed even to lay a single egg this year andlast.

A|X, ~15 years old, but zero young (V. l'herault)

Like A|X, few of our breeding birds are encounteredelsewhere. We have no idea where theywinter or which migratory routes they use. More than ¾ of the annual cycle of the vast majority of the birds westudy is veiled from us…this is not so with “Joe’s Hag”.

In 2 short years, the Hag has shown us that migratory routesbetween years are not necessarily fixed (first through Texas in 2009 and then through Florida in 2010), and it’s clear birds that breed at highlatitudes (69°N) do not necessarily winter at low latitudes (6°).

This year she identified for us what may bethe outer limits for a peregrines breeding at the northern limits of mainland Canada. It seems the narrow margins experienced bybreeders far north of the Arctic Circle haveat least some slack.

Her inward migrationstarted normally. She departed from her wintering territory in Colombia in synchronywith other peregrines wearing GPS PTTs. Her rate of travel matched thosedocumented previously in our study and others. She typically stopped for 2 or 3 days after a fewdays of back to back passage, including a 2-day stopover on South Padre Islandwhere she had been trapped 19 months earlier. Everything, it seemed, was going according to plan.

Then, in early June, soon after she crossedinto southern Manitoba,the Hag’s rate of travel slowed dramatically, then stopped. And to make matters worse, hertransmitter entered “Hibernation Mode”, then stopped functioning altogether.

As usual, most birds arrived on territory in late May, but the last signal we received from the Hag wason June 10^th at a location almost 1000 miles south of her breedinglocation. She was at least 2 weeks late,her 2010 eyrie was occupied by Rough Legged Hawks, and the male with which shehad been paired was also absent. We were in thedark – everything about her was veiled from us once again, perhaps for good!

Spring survey in late May as peregrines arrive to breed (V. l'herault)

The possibility of a re-encounter seemed slight, but we needed to make sure andwanted (even more) one last shot at trapping her. Mark Prostor had put the PTT on her and he wasdetermined to get it off if at all possible. He and Barry Robinson set out on August 5^th,when most pairs are feeding young between 10 and 14 days old.

Here’s how Mark tells the story...

Getting to the Hag’s site is no easy task. From our field cabin, it first requires a 18mile ride in freighter canoe followed by 10 very rough “tundra” miles on HondaATVs just to reach the band of cliff on which she may be perched.

The Coxe Islands from the Freighter canoe (M. Fredlund

We drove the cliff base surveying for any signs of raptors. Twosites that turned out to be Rough-leg sites initially raised our hopes, but 4hrs intothe search our initial expectation that she’d not made it back seemed most likely. As we approached the end of the longband of cliff, I decided to deploy our trap in an attempt to bring any not yetseen falcons to us instead…it was a long shot, and resulted in nothing.

Rough-legged Hawk (G. Court)

With cliff and options running out fast, it seemed like agood time to do nothing at all but wait, watch and eat lunch. Thetrap got no attention other than that from Barry and me. Then, over the sound of the wind, I heard whatcould have been the kak-kak-kak of a peregrine.

“Barry, did you hear that?”

We both turned and saw a male peregrine land atop a large boulder, andperched below him was a female. We had a pair of birds, and the female was wearing aPTT. Joe’s Hag had made it back, and she wasdefensive! Barry searched to the east. Ihad not searched far west when I found the nest ledge with three “very” youngchicks…the eyes of one had not yet opened. The Hag’s brood was 10 to 14 day younger thanmost of the other broods we knew of.

The day was warm, but the age of the chicks left little timeto trap the Hag. She returned to theledge 15 minutes after Barry and I had hidden ourselves, and it took only 5 minutesmore to trap her. She was in beautifulcondition with no abrasions whatsoever from wearing the harness for over ayear. But, on the patagium of her leftwing was a well-healed, but still apparent injury. Could this have slowed her down in the spring?

On the way out we drove past the cliff. Shewas back at the ledge with her young. The PTT felt damn good in my pocket.

The "Hag" is coming...

2011-05-01T14:13:00.036-06:00

Time, technology and luck have broadened our view of the "Hag's" life in ways that the critically important, but brief encounter with her on the beaches of South Padre Island in mid-October 2009 could never do.

The "Flats" of Padre (photo: P. Andreano)

For those unfamiliar with the Hag’s history, she was re-captured in 2010 breeding in the high Arctic, and spent last winter in northern Colombia. But with the Austral summer now over, she and thousands of other Arctic-nesting peregrines are focused northward intent on raising the maximum number of offspring they can. For that to happen, they must first fly several thousand miles, contend with uncertain weather, evade predators and capture sufficient numbers of prey to ensure they arrive in the high Arctic well nourished and ready to lay a full clutch of eggs.

One of the "Hag's" neighbors on a full clutch of eggs

The most recent data for the "Hag" indicate that she flew a little more than 700 miles in 5 days from her wintering territory through Panama and Costa Rica, and settled in southern Nicaragua for at least 36 hours.

Looking north from Colombia to Panama and Costa Rica

Although her current location is obviously tropical, it won't be long before she and and other Arctic-nesting migrants reach the still snow-covered landscapes of the sub-Arctic. They'll press onward leaving the snow-free zone far behind them.

MODIS (May 7, 2011) image of Churchill, MB (red dot), and snow and ice in blue, open water in black, vegetation in green.

All things being equal, the "Hag" will arrive at her nesting cliff to find many potential nest ledges drifted in with hard-packed snow, ponds and bays frozen solid and prey will be more scarce than at any other time of the year.

Still frozen spring conditions (Photo:B.Robinson)

Soon thereafter, with the sun positioned higher on the horizon and 24 hours of daylight, conditions become generally mild, which combined with prey-rich landscapes can turn the Arctic into a peregrine factory.

(Photo:B.Robinson)

More soon on the Hag's progress.

Alastair

More than a glimpse...

2010-12-11T09:50:00.020-07:00

Bird banders generally expect the rewards from band returns to be few, far between and more "vignette" than "mini-series", but within months of receiving a band on South Padre Island (SPI) in Fall of 2009, Joe's Hag began sharing more of her story than could be told from that first encounter.

That day, her weight and size told us she was a "she"; her plumage indicated that she was at minimum in her third year of life...and the long history of banding peregrines on SPI suggested strongly that she was a tundra peregrine. But from where exactly had she come? And where was she going? Had she bred successfully the previous summer? Would she survive the remainder of her migration, that winter and the subsequent return trip to the breeding grounds.

She did survive, produced 4 young, and we confirmed our suspicion that she is a tundra peregrine. In July 2010, she was captured again - this time in the Canadian High Arctic on the Melville Peninsular. She was fitted with a GPS satellite transmitter, and we "watched" as she foraged up to 40 miles from her eyrie, and on occasion remained more than 20 miles away from her nestlings for as many as 36 hours, except for brief visits presumably to deliver prey.

The male paired with Joe's Hag feeds a Lapland Longspur to 4 nestlings

In the latter half of September, we watched further as she left her breeding territory traversing Southampton Island and much of the Hudson Bay, presumably intent on reaching the Texas Gulf Coast where she'd been captured 11 months earlier. But Joe's Hag, it seems, had other ideas in mind...bearing SE from the Churchill shelf, she made decisively for Florida never coming closer than 1000 miles from Padre resulting in 2 entirely different migratory routes south in as many years.

Via Florida rather than Texas

Five weeks and over 5100 miles after leaving her breeding territory, Joe's Hag arrived on her wintering territory in northern Colombia. With a little luck, we'll watch her fly north and see her once again at the cliff on which she breeds.

Alastair

A summary for Scott

2010-12-10T10:37:00.013-07:00

Few would likely argue that a band fixed to the leg of a bird is a cause for worry by those who band birds...but attaching a satellite transmitter to a bird is a different matter. Yes, guidelines exist that help to resolve the conundrum, and good arguments can be made that do or don't tip the balance in favor of securing a tracking device to a bird that migrates several thousands of kilometers twice annually.

Banded Peregrine (Todd Kemper)

Most reasoning rests on the trade-off between risks that accrue for the individual and the benefits that can applied to the population...but the "recipe" that ultimately governs our insights into both obligates the use of a sufficient number of individuals - i.e. go big or go home.

Peregrine with PTT (V. L'Herault)

Some time ago a colleague interested in what effect the Deepwater Horizon oil spill may have on Peregrine Falcons that migrate through the Gulf of Mexico with millions of songbirds, shorebirds and waterfowl asked me for a summary of the tracks for peregrines that we've followed.

The following southern migration tracks of 12 individuals hint that the Gulf Coast of Louisiana, Mississippi and Alabama receives a high proportion of the tundra peregrine population migrating to wintering areas further south, and the coast serves as a "decision point" with some birds simply choosing to overfly the Gulf, while others choose an eastward route through Florida or a westward one through Texas. While most (7/12) opted for a route that took them directly into the Florida peninsular, the remaining 5 spent 1-3 days along a 400 mile section of the Louisiana, Mississippi and Alabama coastlines.

Southern migration tracks of 12 tundra peregrines

Any effect of Deepwater Horizon on Peregrine Falcons remains unknown, but two organizations (the Peregrine Fund and Earthspan) have partnered to study the issue.

Alastair

Joe's Hag Heads South

2010-09-29T20:33:00.007-06:00

Joe's Hag left her breeding cliff in the 3rd week of September and started south for a yet-to-be-determined wintering location somewhere on the South American continent...maybe through Padre Island in the middle of October again as she did last year.

Southward, first stop South Hampton Island

If success is measured in terms of life-time reproduction, 2010 was a pretty good year for Joe's Hag and the male (24 C) with which she raised 4 young. Some pairs fledge a chick or two...for many breeding aged adults the long journey north is just a long journey north...

For some, one storm interrupts a breeding attempt completely

However, if prey is abundant and the weather cooperates, providing for and producing 4 well-fed offspring is routine for an experienced pair of breeders...and from the relative safety of an eyrie that overlooks any prey-rich landscape, hatch year birds need only to eat whatever is brought to the nest ledge to roll the dice in their favor.

The landscape below Joe's Hag's cliff (photo B. Robinson)

Alastair

"Crews-in"

2010-09-11T19:07:00.014-06:00

Margins for Peregrines breeding in the Arctic are narrow…in some years, certain individuals are too narrowly restricted and some of what’s supposed to happen just doesn’t.

Partially hatched chick at abandoned site

This breeding season is all but over; day length and sub-zero temperatures will soon urge breeding birds and, in some cases, their fledged young to leave the Arctic and fly south to their Austral wintering ranges throughout South America.

Future recruit?

Every spring our field crews arrive on the Arctic breeding grounds and try to follow every circumstance as each pair of breeding birds tries to replace themselves and more. We use every voyeuristic tool and trick we can think of to sneak a peak…bands, blood, cameras, satellite tags, feathers, rulers, scales, pencils, paper, rain gauges. But bands don’t go on and wings can’t be measured nor migratory routes traced without snow machines, quads, boats, snow pants, sunglasses, hot tea, rain gear, wrenches, twine, a place to sleep and help when things just won’t go your way. Once in every while, we actually do get a glimpse and gain a little insight, but it’s of no consequence if not summarized, written down and dispensed in ways that are useful.

None of this happens without good people.

The Rankin Crew: Frankie, Poisey, and Alex

Steensby Inlet (Baffin Island) Crew: Theo (AF missing)

Igloolik Crew: Matt, Barry and Mike (missing)

Mark Prostor (Rankin and Igloolik)

Alastair

Joe's "Hag"

2010-09-04T18:32:00.020-06:00

In anticipation of the start of outward migration in a week or two, I thought I'd kick things off by telling you about Joe's "Hag". Hatch year Peregrines on migration are raw, unruly and almost always looking for a meal...they’ll take a run at anything that has a meal or might be one. Haggard birds are elusive and discriminating…each potential meal, it seems, is cautiously assessed before it becomes one.

Dowitcher remains on the flats of Padre Island

At the eyrie, with young to protect, the demeanor of an old “Hag” is best described as "in-your-face" – literally on occasion. So it was without much surprise that this summer Mark Prostor was able to trap a resident female defending 3 young at her nest ledge on the Melville Peninsular near Igloolik in the High Arctic.

Unlike our study area near Rankin Inlet (550 miles to the south), there had been no previous effort made to trap and band adult peregrines in the Igloolik study area, so it was with excitement that Mark found the bird already marked with a USFW band…someone had already trapped this female elsewhere. But who…and where?

An "Old Hag"

Unbelievably, Mark recognized the number series on the band – he’d used the same series the previous fall while trapping migrants staging on the Gulf of Mexico at Padre Island, Texas. We wondered if the answers t0 “who” and “where” would be found in Mark’s field book – his field notes showed that the bands he had used were close (within 5), but he’d not been the one to trap the Hag on Padre…at least we now knew “the where”.

We e-mailed the band ID to Gregg Doney who directs the fall peregrine survey on Padre Island to let him know another Padre bird had been recaptured in the Canadian Arctic – he replied;

Great job, the connections between Nunavut and Padre are growing!

Actually, this was Joe Snyder’s first Padre bird. I remember the scenario very well, because it was Joe’s introduction to the flats (15-OCT-09) and he experienced the “black and white” of behaviors often seen.
We (Joe, Bud, myself) were just south of the silver well-head, after spending about an hour on a Hatch Year male that would never close the 10 foot gap on the trap. We finally called it quits and were in a group, picking up and going over landmarks when an adult female bumped from the flats 250 yards downwind.
I was skeptical, because the Hag seemed skittish and had probably watched our entire routine with the male…but even with 3 ATVs in the area, she came right in and bound.
Joe then worked her to hand.

Joe and 1947-00531 on Padre 2009-10-15

1947-00531 and nestlings on the Melville Peninsular, NU 2010-08-09

Alastair

"Blue's demise"

2010-06-22T20:02:00.012-06:00

Three weeks ago (May 28/29) Blue roosted near the Botanical Gardens on the west end of Roatan Island, Honduras before over flying Glover Reef making landfall in Belize 30 miles south of Belize City on May 30.

West end of Roatan Island, Honduras

Glover Reef

From there he over flew the Gulf of Mexico making landfall just south of Brownsville, Texas on the Mexican side of the Rio Grande River by June 2. A total of 1150 miles in 4 days.

Blue's route May 28 - June 2

On June 1, Mark Prostor and I checked Blue's territory and found the site still occupied by only a lone female. No doubt that he would be one of the late arriving breeders, but not so late that he could not successfully raise a brood of young.

By June 5, Blue had added another 1000 miles and was located near Cunningham, Kansas. He'd been traveling 300 miles daily for more than a week, and early in the evening on the 5th, Blue found a well-treed farm yard surrounded by irrigated crop land.

Roost location June 5/6

Based on his rate of travel, I anticipated that his next set of GPS locations due 3 days later would show Blue's location to be near Lake Manitoba, and less than 700 miles from his breeding territory. Surprisingly, the location data on June 9th indicated little movement which could easily be explained by GPS error alone...worse yet, the activity sensor indicated that the PTT had not moved in 3 days.

Data we received on the 12th confirmed that the PTT was stationary, but our field crew surveys on Baffin Island, the Melville Peninsular and Rankin Inlet left little time to track down what had happened to Blue.

No activity from June 5 to 12 near Cunningham, KS

Once back in Edmonton, I contacted Kerri Steffen at Cunningham Courier. who passed me along to a couple of biologists with the Kansas Department of Wildlife and Parks. Over the next couple of days Mark Van Scoyoc, Ken Brunson (both with KS Wildlife and Parks) and I exchanged information about Blue's location data, PTT frequency, search strategies, possible outcomes and the area around the farm yard.

Yesterday morning, I received the following message from Mark...

...we found your transmitter and the remains of the male peregrine. Just a wing was left of the bird itself. Ken will be sending you some photos...

And a little later, this one from Ken (along with the images below)...

...I brought up our bat biologists who were using a radio receiver related to some transmittered bats about an hour away from us but, unfortunately, we could not get their radio to encode your frequency. It turned out that the transmitter and wing were not all that hard to find after all . Jeff Miller was the one who discovered it mixed in with some branches on top of a shed roof. Glad we were able to find it. Our best evidence is that Blue met its demise from the talons of a Great Horned Owl which had already claimed the farmstead as its territory...

Looking south to the farm yard

The yard and "starting point" for the search using PTT locations

Jeff Miller finds PTT and wing on the roof of a shed

The shed

PTT and Blue's wing

My thanks to Mark and Ken for their time and resources, and to Whitney Haskell, Jeff Miller, Mike Rader and Murray Laubhan. Their efforts have provided invaluable insight into the events that lead to Blue's demise.

From L to R Whitney Haskell, Jeff Miller and Laurie Yasui

The field crew (Alex Anctil, Poisey Alogut and Frankie Jean-Gagnon) currently working at Rankin Inlet report that a male and female are resident at the site where Blue bred last year, and that a clutch of 4 eggs was completed by June 21.

Alastair

No sign of Red...Blue still in the tropics

2010-05-28T11:19:00.005-06:00

Blowing snow, poor visibility (fog) and gusts up to 50 mph have kept us from going out today - so I thought I'd get a note posted to the blog. Mark Prostor and I visited Red's territory on May 22, and found the resident female and an unbanded male. The nest ledge used last year is drifted in with about 12 feet of snow. To date, only about 1/3 of the sites in the study area (about 36 in total) are occupied.

Blue opted for the "safe, but longer" route having circumnavigated the Andes by bearing north until he reached the Venezuelan coast, then flying westward to Panama. His most recent location has him only 7 degrees further north than he was on May 13. Each degree of latitude is about 69 miles, so he is only 500 miles further north than he was 2 weeks ago despite having traveled more that 1900 miles.

At this rate, he will undoubtedly be one of the late arriving breeders (certainly later than he was last year) - but his timing may yet prove to be to his advantage. His territory remained unoccupied as of May 26.

Route to May 28

More next week...Alastair

Hmmm...decisions, decisions?

2010-05-14T19:33:00.010-06:00

This week Blue traveled another 535 miles (since the May 7) for a cumulative distance of over 2800 miles thus far. Surprisingly he once again veered from the expected NW bearing to one that is now taking him NNE. If he maintains his current bearing, then it's possible that he may ignore the Andes and Panama altogether opting to take the Cuban route north as he did to come south. Alternately he could cross the Caribbean Sea from Venezuela or Columbia directly to Central America (Costa Rica or Nicaragua). Both have their risks and benefits - the former is ultimately a shorter route to Rankin Inlet, but it means crossing a minimum of 400 miles of open ocean. The latter offers the relative safety (in my mind at least) of the Central America land bridge, but is a significantly longer route to Rankin Inlet. Complex decisions when time is of the essence for those individuals breeding in the Arctic.

Route taken through May 13\

His last received data point indicated his position to be on the northern fringe of the Amazon Jungle straddling the border between Venezuela and Colombia (see image below)...

Blue's location on northern edge of the Amazon

...and that he roosted on a hill (red circles in lower left corner of the GE rendition below) overlooking the Orinoco River that divides Colombia and Venezuela . In the background, about 30 miles from the the river, you will a series of mountains...

GE rendition and most recent location (lower left)

...Panoramio photos show that the mountains include a well known table-topped mountain (Tepui or Tepuy) called Autana Tepui...I can think of worse places to stop.

View of Autana Tepui from village of Seguera

Autana Tepui

More next week from the Arctic.

Alastair

Favorite things...

2010-05-03T16:00:00.017-06:00

Blue has now completed a little more than 1/4 of his migration having flown 2300 miles in total. After arriving at Lake Tefe in Brazil on the Amazon River, he remained there for 6 days, then flew 190 miles taking the expected NW bearing toward Panama, which is still 1000 miles from his current location.

Route to May 7

Last week we saw Blue surprisingly retrace his route by flying south before turning north east toward Lake Tefe, which incidentally is very similar to the lake where Blue spent the winter.

Considering his dramatic change in direction, apparent preference for big lakes and the 6 day respite makes one question if he just "stumbled" across Lake Tefe.

Recall too (see April 24 post) that while wintering Blue repeatedly used a cell phone tower in a very urban setting...well the GE image with GPS locations and the photo below show that he repeated this behavior in the city of Tefe (click on each one to see and compare the full sized versions).

GE view of favored locations in Brazilian city of Tefe

Photo of Tefe (similar to GE image above)

Sure makes one wonder whether we're seeing random behavior or evidence of preference for a few favorite things.

Update on spring conditions...earlier (April 19) I posted some MODIS imagery from April 10 2009 and 2010 that show how spring conditions can differ from one year to next. The following 2 images (about 450 miles X 450 miles) below show snow cover in the region on the Hudson Bay near Churchill, Manitoba (red dot) on May 5th 2009 and 2010.

Churchill snow cover May 3 2009

Churchill snow cover May 3 2010

Amazonia...and beyond

2010-05-02T08:02:00.008-06:00

Blue flew an additional 580 miles between April 25 and April 30, his route has taken him to the center of the Amazon Jungle. Last October, he crossed the Caribbean Sea from Cuba and made landfall in western Venezuela - Peregrines typically perform a "loop migration", which suggests that he'll resume his path NW and through Colombia into Central America...to do this, he must first cross the Andes.

Route up to April 30

There are very few Panoramio images posted in the immediate vicinity of the GPS locations , but the two below are typical of the region...

Canopy

Tributary of Amazon River

It's a little surreal to think that in 4 or 5 weeks, (all things being equal) he'll be on territory near Rankin Inlet where it will be like this...

"Panorama Island" with Rankin Inlet in the background

A brief rest and then...

2010-04-25T10:36:00.010-06:00

Blue has now covered just under 1500 miles of the approximately 8500 miles it will take to get to Rankin Inlet. His route north remains somewhat similar to that taken south (purple = southern route, blue = northern route).

Route up to April 25

Acquiring 12 locations per day (1 fix every 2 hours) tells us a great deal about active and sedentary periods...for example, this peregrine habitually travels at a approximately 30 mph, starts out at about 10 a.m. on migrations days, and usually stops to roost between 8 p.m. and 9 p.m. So...generally active for about 10 hours and sedentary for about 14 hours per day. Of course, there is some variability; here's a brief synopsis of activity between the 20th and 24th...

20 - 21 = sedentary
22 = 400 miles
23 = 285 miles
24 = 229 miles

Locations on the 20th and 21st were concentrated among 4 or5 areas of about 8 square miles each that appear to be fenced and are apparently (Panoramio images) grazed by livestock (cattle and/0r goats) .

Goats

Cattle

The area appears to be quite arid, and some watering holes like the one below are artificial. These locations are probably permanent and are undoubtedly very attractive to many bird species in the area.. It's likely that Blue hunted these watering holes before resuming migration.

Livestock watering hole

...more soon, Alastair.

Panoramio tells the tale

2010-04-24T09:59:00.014-06:00

In mid-March, whilst wintering in Brazil, Blue began spending many hours each day and night in a very urban location as shown in the GE image below - to me it looked like he may be using the trees around which the GPS locations were scattered, but I couldn't tell from GE what was so special about the few trees he seemed to have selected when there were so many others just like it to choose from?

The "Roost" location

I e-mailed the GPS locations to my colleague, Mark Prostor, to get his thoughts on what might be so attractive to the peregrine. He took a look at the locations in GE and then started looking for Panoramio images close by...he found one of the swimming pool below(and bottom left corner of the GE image above), and pointed out the GPS fixes were located at the cell phone tower that can be seen in the top right corner of the pool photo.

The Pool

It also be came apparent after a few weeks that GPS locations would periodically be situated in the surrounding soy bean fields like the one below located half a mile from the cell tower.

Soy bean field

Looks to us like the cell phone tower served as both safe overnight roost and strategic location from which he could hunt prey in the nearby agricultural lands.

Alastair

Red's fate to be determined

2010-04-21T15:25:00.006-06:00

Red's PTT stopped transmitting on Dec 24, 2009. So...in early January thanks to Oscar Beingolea who traveled 700km from Lima, Peru, and spent several days in the field searching Red's home range in an effort re-trap him and remove the PTT, we gained some insight that was otherwise not possible.

Although Oscar could not locate the peregrine or the PTT, he visited several locations that had been used repeatedly by Red, and told us some things not apparent from our limited perspective gained solely from Google Earth.

In one case, viewing the GPS data in Google Earth showed repeated use of a location that was devoid of any structure all, and not something at all that one would predict as typically "used" by peregrines. Oscar soon discovered that a small village with a new water tower had been constructed there at some point after the satellite imagery used by GE, making it "appear" that the peregrine was perching in an unlikely spot.

In another instance, Red abruptly stopped using what had to that point been a heavily-used overnight roost. We had high hopes that the peregrine would be found at or near that location. On his first visit Oscar discovered a small plot of land left fallow and surrounded by Algarrobo trees. Here is how Oscar described what he and two of his colleagues (Fernando and Pedro) found...

"...something has not been right with his "favorite place", since we could find no evidence of the falcon's presence at the place he likes. Last time we were there, we could see that two trees had been cut down next to the main tree standing there. We were not sure about how long ago had been they cut down. There weren't any small branches around suggesting they had been used for charcoal already, but how long ago?.

The weather is extremely hot and its is not rare that the trunks are left drying outdoors till they are needed. That first day at the "place he likes" we found no logging activity around the cut trees, other than a stump 50 cm tall and some other small pieces on the ground. Well, today at "the place he likes", we met some loggers that were cutting the trunks into smaller pieces, less than 12 meters away from the main standing tree. I'm sure that is enough to scare away any falcon. Furthermore, when I asked to the loggers how long ago had they cut down the trees they told me "15 days ago". Alastair, that cut is really fresh and must have scared the falcon from the place he likes. They had probably have even cut HIS FAVORITE TREE..."

The "Favorite Place"

Once back in Rankin Inlet next month, Red's breeding site will be one of the first places I check ...I'll let you know what I find.

Alastair

Blue headed for Rankin Inlet

2010-04-19T14:43:00.009-06:00

After spending the Arctic winter on the Paraguay/Brazil border, Blue began the first leg of long inward migration back toward his breeding territory near Rankin Inlet this week. His return route (in blue) is so far quite similar to that taken south (in purple) 4 months ago. Last year he was on territory before the end of May. For his timing to be similar, he has about 40 days to travel more than 8500 miles. I'll be on the ice of the Hudson Bay by then, and will hopefully get the chance to actually watch him arrive knowing exactly how far he has flown in an effort to get an opportunity to produce more young. In the meantime, his most recent location has him 400 miles NW of his wintering territory.

This spring is already quite different than last. The first of the 2 images below show snow cover over the southern portion of the Hudson Bay and James Bay on April 10, 2009, and the second shows snow cover on April 10, 2010.

Snow Cover April 10, 2009

Snow cover April 10, 2010

Rankin Migration - 16 Dec. 2009

2009-12-16T18:59:00.000-07:00

Both birds have now completed their respective migrations – BLUE flew an additional 1050 miles since the last update making his total distance flown about 8900 miles over 9 weeks (left in the last week of September and arrived in the last week of November). His wintering territory is in right on the border of Paraguay and Brazil – in fact he tends to overnight in Brazil and spend daylight hours in Paraguay on lake Itaipu.

RED flew 150 additional miles from his last reported position and has settled into his wintering territory in northern Peru having flown a total of 6500 miles in about 8 weeks (leaving and arriving on approximately the same dates as BLUE)

Interestingly both birds winter on the outskirts of small communities.

Rankin Migration - 23 Nov.. 2009

2009-11-23T18:58:00.001-07:00

Last week was a big week for BLUE, he flew over 1400 miles making his way through Colombia, Peru (briefly), Brazil and into Bolivia to a location 14 degrees south of the Equator (yellow line). He has now flown over 7700 miles. I’m wavering on last weeks suggestion that he will winter somewhere western South America…data collected from PTTs deployed in the Rankin Inlet study area by Earthspan (http://www.earthspan.org) in 1994 perhaps suggest an alternate wintering location. I have plotted two 1994 routes (PURPLE and GREEN) taken by females migrating to their respective wintering grounds in southern, coastal Brazil…the route that BLUE has taken this last week is remarkably similar to those taken by PURPLE and GREEN 15 years ago. Of interest too is the timing – BLUE and GREEN had almost identical timing while PURPLE was about 10 days ahead. The 1994 birds completed their respective migrations in the first week of December.

Distance-wise RED had a much more sedentary week in comparison to BLUE, and flew an additional 330 miles just crossing into Peru (total distance flown is now about 6400 miles). I’ve compared RED to two other birds (WHITE and ORANGE) currently being tracked by the Falcon Research Group (http://www.frg.org). For those who have visited the FRG site you’ll already be aware that WHITE and ORANGE spent the breeding season on Baffin Island and recently completed migrating, returning to their respective wintering areas in coastal Chile. Based on comparisons of route taken or timing, RED is either very close to reaching his wintering territory or alternately will make a final push southward. Other birds have shown a tendency to make longer daily flights in the last few days of migration, so I’ll go out on a limb and suggest that we’ll see BLUE much further south next week than he currently is.

Alastair

Rankin Migration - 14 Nov. 2009

2009-11-14T18:57:00.001-07:00

Having travelled about 6300 miles in 53 days (700 additional miles this week) and 6000 miles (970 additional miles this week) in 52 days, Blue and Red (respectively) reached the Equator this week and appear to be headed for wintering locations somewhere in the western South American.

East to west the birds are separated by the Andes with Blue having remained on the eastern side, while Red has used a more-or-less coastal route on the western side of the Andes. North to south, however, Blue is only 30 miles further south than is Red despite significant passage of time and distance.

As of the last update Red flew south from the Caribbean Sea on the Panamanian coast stopping briefly on the coast of the Gulf of Panama. It’s not unusual for peregrines to cross large bodies of water like to the Gulf of Mexico or in this case the Gulf of Panama over to Colombia…what is a little usual is the route that he took – he flew 275 miles south through the Gulf of Panama into the Pacific Ocean, then made a “U turn” and flew 150 miles back towards where he’d come from ultimately turning southward once again coming ashore in Colombia 106 miles later.
While it is possible that he found a boat or buoy on which to rest, the data indicate that he was airborne for 26 hours and covered more than 530 miles.

More next week.

Alastair

Rankin Migration - 06 Nov. 2009

2009-11-06T18:47:00.001-07:00

Here's a synopsis of the entire migratory route for both birds, and below is one of their respective routes in Central America and northern South America.
Over the last week, Blue covered another 450 miles bringing his total to over 5550 miles. As most of the Rankin band returns have been from Brazil, I expected his route to continue south easterly. He has done the opposite and has headed west toward Bogotá and the eastern foothills of the Andes. The image below shows a GE version of a location on an escarpment over looking a river valley near Villanueva, Columbia where he spent 16 hours – it’s pretty easy to imagine the relative ease with which he could likely fly down and capture prey from that vantage point
… and this Panoramio image was embedded in GE 2.5 miles from his roost location – pretty nice habitat.
Red hugged the Costa Rican and Panamanian coastline on the Caribbean Sea fro an additional 425 miles for a total of nearly 5000 miles. His most recent data point shows that he has changed direction abruptly and has headed south bringing him a location near Picacho Mountain and within 10 miles of the Gulf of Panama.
The Panoramio image (below) was embedded in GE 0.5 miles from his roost location – pretty nice habitat too!
Alastair

Rankin Migration - 29 Oct. 2009

2009-10-29T18:46:00.002-06:00

Blue traveled another 800 miles between Oct 21 and Oct 28 for a total of 5100 miles on migration. This week took him over the Venezuelan Andes and south into Columbia near Gaviotas. The GPS transmitters that these birds are wearing also record ambient temperature. When combined with lack of movement and decreasing battery power, low temperatures can be indicative of mortality. Typically temperatures are between 28 and 32 degrees C, so I was a bit alarmed when I saw temperature values below 10 degrees C. After checking altitude in Google Earth, I realized that Blue was in the mountains 2400m above sea level after having left the lowlands west of Lake Maracaibo (400m ASL) less than 8 hours earlier. The data show that he roosted overnight on a river bank…I think the sudden and temporary drop in temperature means he may have taken a bath first thing in the a.m.!.

The following GE terrain image will give you some perspective of his movements in the mountains.

and the following two photos are Panoramio images imbedded in GE and were very close to where he roosted.
Red added another 600 miles to the previous tally of 3900 miles for a total of 4500 miles to date. His most recent data point had him 39 miles NW of San Jose, Costa Rica.

Rankin Migration - 22 Oct. 2009

2009-10-22T18:44:00.001-06:00

Blue has logged over 4300 miles as of midnight Oct 21, a month after leaving his territory in Rankin Inlet where it is currently -11C with snow and a 20 mph wind – wind chill is -22C. His last data point had him a few miles east of Remolino, Columbia where it 25C with some scattered showers and a 2 mph wind. He left the Cuban mainland just west of Guantanamo Bay at about 0900Z on Oct 20 and (apparently) without stopping flew 702 miles across the Caribbean Sea arriving 34 hours later on the Columbian mainland at 1900Z on Oct 21. His 2 hr data points are very evenly space and show he was travelling at a relatively constant speed of just over 20mph, wind speed was apparently low (about 3mph from the NW).

Red has been sedentary since the last update, logging an additional 200 miles for a total of over 3900 miles…his data points are mostly clumped along the coast near Cuyamel on the Honduran side of the Guatemalan/Honduran border.

Alastair

Rankin Migration - 17 Oct. 2009

2009-10-17T18:43:00.001-06:00

Blue has now logged more than 3000 miles and has continued to track SE. His last observed location was on South Bimini Island (part of the Bahamas) 56 miles ESE of Miami, Florida (quite a departure from other birds that have taken the Florida route). He stopped 3 times while in the West Palm Beach area, each occasion in a location significantly less populated than the surrounding urban landscape (a 25 square mile water catchment area, an up-scale acreage-type residential area and a golf course). He also used a natural area along the Fox River in other-wise highly populated region near Elgin, Illinois on a previous stop-over.

Red is 3700 miles into migration, and did cross to Cuba (the far western end near Cabo de San Antonio) before making the 125 mile ocean crossing to the Yucatan. He meandered southward generally along the coastline and his most recent data point shows him to be 17 miles WSW of Belize City.

Attached also are two photos from birds trapped on Padre Island – the first is of an adult female that first captured as a hatch year bird in 2000, and the second is of a blonde second year male.

Alastair