Wednesday, December 16, 2009

Rankin Migration - 16 Dec. 2009

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.

Monday, November 23, 2009

Rankin Migration - 23 Nov.. 2009

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

Saturday, November 14, 2009

Rankin Migration - 14 Nov. 2009

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

Friday, November 6, 2009

Rankin Migration - 06 Nov. 2009

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

Thursday, October 29, 2009

Rankin Migration - 29 Oct. 2009

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.

Thursday, October 22, 2009

Rankin Migration - 22 Oct. 2009

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

Saturday, October 17, 2009

Rankin Migration - 17 Oct. 2009

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

Wednesday, October 14, 2009

Rankin Migration - 14 Oct. 2009

Blue has flown over 2500 miles, and despite an initially similar route to those taken by birds in 2008 (that took them westwards), veered eastwards to visit Chicago for a couple of days. He has tracked SE and now looks to be taking the Florida route.

Red has now flown over 3000 miles and was in the Dry Tortugas at last record and is likely currently on route to Cuba or directly across the Gulf.

Here are a couple of images taken during South Padre Island Peregrine Survey in Texas – the first photo is of a freshly eaten coot (a Hatch Year female with full crop was sitting not far away), the other is a pretty typical of the Padre Island habitat where many hundreds of peregrines stage on their way to South America.

Alastair


Friday, October 2, 2009

Rankin Migration - 02 Oct. 2009

Both Rankin birds are now well into migration – As of October 1, Blue is in Minnesota and has flown over 2000 km since September 23 and Red is in Wisconsin with over 2700 km covered since September 22. Both have flown west of the Great Lakes and based on data collected in 2008, Blue may take a circum-gulf route perhaps via Padre, and Red at this point seems destined for Florida.
The above photo of red on territory was taken by Vincent L’Herault this summer.

Alastair

Wednesday, September 23, 2009

Rankin Migration - 23 Sept. 2009

Hi all,

This year (again with Mark Prostor’s expertise) we instrumented 3 male peregrines with 22 gram GPS PTTs (MTI). All were raising young when they were fitted with PTTs. We have been collecting 12 locations per day to determine home range, and will maintain the fix frequency throughout migration. I’ll send out updates periodically on their progress as they head for South America..

In early Sept, one of the males was killed (likely shot from the looks of the carcass) after the single chick that the pair managed to hatch died. The other 2 successfully raised young.

One of the remaining males began his outward migration yesterday Sept 22 between 1400-1600 UTC. He travelled SW in a series (5) of short 3-20 mile hops every 2 hours arriving on the shore of Maze Lake 30 miles inland of Whale Cove at midnight UTC on Sept 23. He remained there up to and including the last data point at 1400 UTC. The pair laid 4 eggs and raised 2 young, a female and a male that are 29 and 30 days fledged respectively as of the male’s departure. The image below shows the male bringing in a lemming on the day that the first chick hatched.
The other male is still in Rankin, but I suspect that the data will show his departure at the next download in a couple of days.

Alastair