On Tuesday, Island Girl remained in the same general area of northern Peru instead of continuing to fly north. She appears to be sort of taking a day off. She may be tired. She may be building up her fat reserves. She may have found a good prey source. Maybe she likes being back in a vegetated area after the desert. Who knows?
Sort of off-topic, but I also wonder how many days she goes without bathing when crossing the Atacama. It isn't really known how often a peregrine does bathe while on migration. Maybe that also has something to do with her delay. Again, who knows?
She moved only a short distance of 27 km (17 miles) for the day but put in for the night near sea level (224') in a huge agricultural valley to the east of the town of Tambo Grande.
The Google Earth image is clouded over heavily but it appears that she roosted on the edge of a cultivated field.
29 April, 2010
27 April, 2010
Island Girl Approaches Ecuador
On Monday, her 13th day of migration, Island Girl traveled 195 km (121 miles) NNE into the Piuran Mountains of northwestern Peru. She did continue to follow the foothill route as we expected.
So far, she has covered 3,762 km (2,338 miles) on her northbound migration.
This is a really beautiful area of Peru. I've been there many years ago. They grow citrus fruit and coffee in the region. There is much more vegetation than further south and the coastline to the west is famous for its surfing beaches.
She was only about 50 km from the border with Ecuador last night and has probably arrived there today.
The Google Earth image is pretty bad here so we do not have much detail on her roost site. It looks like she was on another mountain side about 1,200 feet in elevation and overlooking a river valley below. This location once again borders a rich agricultural valley, no doubt with lots of prey.
So far, she has covered 3,762 km (2,338 miles) on her northbound migration.
This is a really beautiful area of Peru. I've been there many years ago. They grow citrus fruit and coffee in the region. There is much more vegetation than further south and the coastline to the west is famous for its surfing beaches.
She was only about 50 km from the border with Ecuador last night and has probably arrived there today.
The Google Earth image is pretty bad here so we do not have much detail on her roost site. It looks like she was on another mountain side about 1,200 feet in elevation and overlooking a river valley below. This location once again borders a rich agricultural valley, no doubt with lots of prey.
Island Girl Continues Through Northern Peru
On Sunday, Island Girl pretty much duplicated her behavior from last year, i.e. flying along the foothills of the Andean front and slowing a bit. She covered 229 km (143 miles) for the day and ended up east of Cartagena where the broad northern plain begins to extend to the northwest.
If she follows form, she will diverge from the coastal route here and continue to follow the foothills to the north. I'd guess that the onshore flow of Pacific winds pushing up into the mountains assists her on her way.
As she often does, she slept on an arid ridge near the top of an isolated mountain range bordered by two fertile agricultural valleys. Again, no shortage of food in these areas. There was a large reservoir, the Reservorio de Tinajones, 18 km (11 miles) to her south.
Her roost site was located at about 1,557'. Using Google Earth, one can see the presence of small shrubs of some sort, indicating that she is now approaching the tropical forests.
Looks like she has once again successfully traversed the driest desert on earth.
If she follows form, she will diverge from the coastal route here and continue to follow the foothills to the north. I'd guess that the onshore flow of Pacific winds pushing up into the mountains assists her on her way.
As she often does, she slept on an arid ridge near the top of an isolated mountain range bordered by two fertile agricultural valleys. Again, no shortage of food in these areas. There was a large reservoir, the Reservorio de Tinajones, 18 km (11 miles) to her south.
Her roost site was located at about 1,557'. Using Google Earth, one can see the presence of small shrubs of some sort, indicating that she is now approaching the tropical forests.
Looks like she has once again successfully traversed the driest desert on earth.
26 April, 2010
Island Girl Heads Down Towards Coast
On Saturday, Island Girl flew another 411 km (255 miles) continuing on her rapid pace through Peru. She is really covering ground and as expected, she descended down and west from her high altitude roost to rejoin the classic coastal route. She is now in northern Peru and roosted within 22 km (14 miles) of the coastline, and southeast of Trujillo about 51 km (31 miles).
Her roost site was also a classic. Located on an east-facing slope of a dry mountain ridge at 1,694 feet in elevation, it was situated immediately between two heavily-cultivated, agricultural valleys with major rivers flowing through them.
Based on our earlier experiences in Peru, we can predict that there will be an abundance of bird life in these valleys, including Rock Pigeons, several species of doves and good populations of passerines. Looks like a very good place to stop off and hunt.
She should be reaching Ecuador and the equator soon.
Her roost site was also a classic. Located on an east-facing slope of a dry mountain ridge at 1,694 feet in elevation, it was situated immediately between two heavily-cultivated, agricultural valleys with major rivers flowing through them.
Based on our earlier experiences in Peru, we can predict that there will be an abundance of bird life in these valleys, including Rock Pigeons, several species of doves and good populations of passerines. Looks like a very good place to stop off and hunt.
She should be reaching Ecuador and the equator soon.
24 April, 2010
Roosting Again Above 16,000 Feet!
Island Girl is making really good time migrating through the mountain highlands of Peru.
In just three days, she is more than half-way across the country and has travelled well past Lima.
Yesterday, she flew 368 km (228 miles) past the marshes, high altitude lakes, ponds and extensive grasslands (pampas) of the Puna region.
She roosted on the south ridge of 17,000 foot Nevado Alcay, a snow-covered mountain located about 44 km (27 miles) SW of Lago Junin. The site was just 4.6 km (3 miles) above Highway 18.
We first discovered and described this type of high altitude roosting among migrant peregrines four years ago when Linda, another one of our Chilean radio-tagged peregrines, roosted just below 16,000 feet. High altitude roosting by peregrines had not been described prior to that event and was a surprise to everyone on the team.
Last night, Island Girl perched at 16, 279 feet, nearly equaling her own record set last year of 16, 302 feet, a difference of only 23 feet in elevation.
Remarkably, both of these records were set within one day of each other, 16, 302' on 22 April 2009 and 16, 279' on 23 April 2010 by the same falcon.
Last year, Island Girl spent two nights at high elevation before dropping down to the coast. We'll see if she repeats this behavior in the next day or two.
In just three days, she is more than half-way across the country and has travelled well past Lima.
Yesterday, she flew 368 km (228 miles) past the marshes, high altitude lakes, ponds and extensive grasslands (pampas) of the Puna region.
She roosted on the south ridge of 17,000 foot Nevado Alcay, a snow-covered mountain located about 44 km (27 miles) SW of Lago Junin. The site was just 4.6 km (3 miles) above Highway 18.
We first discovered and described this type of high altitude roosting among migrant peregrines four years ago when Linda, another one of our Chilean radio-tagged peregrines, roosted just below 16,000 feet. High altitude roosting by peregrines had not been described prior to that event and was a surprise to everyone on the team.
Last night, Island Girl perched at 16, 279 feet, nearly equaling her own record set last year of 16, 302 feet, a difference of only 23 feet in elevation.
Remarkably, both of these records were set within one day of each other, 16, 302' on 22 April 2009 and 16, 279' on 23 April 2010 by the same falcon.
Last year, Island Girl spent two nights at high elevation before dropping down to the coast. We'll see if she repeats this behavior in the next day or two.
23 April, 2010
Island Girl Now in the High Andes
On Thursday, Island Girl migrated along the center of the high Andes Mountains, midway between the coaast and the Amazon Basin. She was NE of Nazca but quite a bit higher at 4,200 meters (13,776'). She did not fly further east towards Cuzco, avoiding a geographic "dead end" which would have resulted in an Amazon Basin route.
She had her best day so far this year in terms of distance, covering 421 km (262 miles) across the lakes and streams of this very rich area. She was about 150 km (93 miles) from the Pacific Ocean.
She roosted on the east face of a ridge, overlooking a verdant river valley and again, at over 13,000 feet in elevation.
If she behaves "normally", I would predict that she will roost high in the mountains again tonight and either tomorrow or the next day drop rapidly down to the coast in a single day. Several of our tagged birds have exhibited this behavior in the past. Let's see what she decides to do.
I should also point out that this is the time/area where we set the altitude record for roosting peregrines in past years. We'll watch for that too.
Amazing birds........
She had her best day so far this year in terms of distance, covering 421 km (262 miles) across the lakes and streams of this very rich area. She was about 150 km (93 miles) from the Pacific Ocean.
She roosted on the east face of a ridge, overlooking a verdant river valley and again, at over 13,000 feet in elevation.
If she behaves "normally", I would predict that she will roost high in the mountains again tonight and either tomorrow or the next day drop rapidly down to the coast in a single day. Several of our tagged birds have exhibited this behavior in the past. Let's see what she decides to do.
I should also point out that this is the time/area where we set the altitude record for roosting peregrines in past years. We'll watch for that too.
Amazing birds........
Wednesday-Island Girl Crosses Into Peru
Island Girl left Chile on Wednesday and flew into the Peruvian desert, probably near the border town of Tacna.
At this point the Pacific coastline of South America curves heavily to the northwest. To follow the classic coastal route, a migrant peregrine also has to change its heading to the northwest.
We have seen different falcons do different things at this juncture. Some stay near the water, others head inland and upwards.
Island Girl decided to go inland and follow the high Andes for awhile. We don't know if this is related to food in the highlands, a navigation/heading issue or something entirely different. But it always seems to happen in about the same place.
She flew 325 km (202 miles) for the day and passed close (within about 25 km) to the city of Arequipa and overflying the incredible Rio Tambo valley.
Her roost site was pretty interesting and sort of puzzling.
The signal suggests that she may have slept on the bottom of a dry river bed in a desert canyon about 2,108 meters (6,917') in elevation. However, we also know that the GPS data can be up to 20 meters off in either direction.
There appears to be a small cliff to the south of the location, right above the dry river bed. Perhaps she slept there.
She was about 56 km (45 miles) NE of the coast and the town of Mollendo.
At this point the Pacific coastline of South America curves heavily to the northwest. To follow the classic coastal route, a migrant peregrine also has to change its heading to the northwest.
We have seen different falcons do different things at this juncture. Some stay near the water, others head inland and upwards.
Island Girl decided to go inland and follow the high Andes for awhile. We don't know if this is related to food in the highlands, a navigation/heading issue or something entirely different. But it always seems to happen in about the same place.
She flew 325 km (202 miles) for the day and passed close (within about 25 km) to the city of Arequipa and overflying the incredible Rio Tambo valley.
Her roost site was pretty interesting and sort of puzzling.
The signal suggests that she may have slept on the bottom of a dry river bed in a desert canyon about 2,108 meters (6,917') in elevation. However, we also know that the GPS data can be up to 20 meters off in either direction.
There appears to be a small cliff to the south of the location, right above the dry river bed. Perhaps she slept there.
She was about 56 km (45 miles) NE of the coast and the town of Mollendo.
21 April, 2010
Approaching Peru
Island Girl resumed her migration yesterday, covering a solid 288 km (179 miles) to the north. This time she flew inland once again, flying over the driest desert in the world.
Last night, she was approaching Arica, the northernmost town in Chile and is now nearing the point where the coast of South America suddenly curves to the NW. This is where some of our birds in the past made a route choice between going due north into the Andes Mountains or curving to the left and following the coastline.
She roosted within 71 km (44 miles) of the city, the gateway into Peru.
Her roost site is awesome and, if you can, check it out on Google Earth. It was located on a huge cirque wall below a flat plain and above a deep river canyon, the Quebrada de Camarones. The town of Camarones was below. The elevation of the roost site was about 4,154'. Spectacular.
Last night, she was approaching Arica, the northernmost town in Chile and is now nearing the point where the coast of South America suddenly curves to the NW. This is where some of our birds in the past made a route choice between going due north into the Andes Mountains or curving to the left and following the coastline.
She roosted within 71 km (44 miles) of the city, the gateway into Peru.
Her roost site is awesome and, if you can, check it out on Google Earth. It was located on a huge cirque wall below a flat plain and above a deep river canyon, the Quebrada de Camarones. The town of Camarones was below. The elevation of the roost site was about 4,154'. Spectacular.
20 April, 2010
Island Girl Puts on the Brakes
On Monday, Island Girl took a day off and pretty much stayed in the same place. No migration for her.
It is tempting to speculate that she was holding up and hunting seabirds along the coast, perhaps regaining weight for the trip but who can say for certain. We do know that prey is far more scarce in the interior than along the coast.
She roosted last night on the same steep slope overlooking the Pan-American Highway and within about a kilometer of the ocean. Once again, she could no doubt see the traffic going by.
It looks like she chose a steep cliff to sleep on this time, which is always a relief to see. Vertical faces deter ground predators to a large degree. Sleeping on the open ground can be deadly.
It is tempting to speculate that she was holding up and hunting seabirds along the coast, perhaps regaining weight for the trip but who can say for certain. We do know that prey is far more scarce in the interior than along the coast.
She roosted last night on the same steep slope overlooking the Pan-American Highway and within about a kilometer of the ocean. Once again, she could no doubt see the traffic going by.
It looks like she chose a steep cliff to sleep on this time, which is always a relief to see. Vertical faces deter ground predators to a large degree. Sleeping on the open ground can be deadly.
19 April, 2010
Island Girl Returns to the Coast
On Sunday, our female peregrine returned to the Pacific coastline. She had continued flying north as expected and flew 168 km (105 miles) for the day.
She roosted on a steep slope overlooking the Pan-American Highway and only 1 km (.6 mile) from the ocean. She could no doubt see the headlights of vehicles during the night and perhaps even hear them.
Her roost was located about 1,286' up the slope according to Google Earth. This is near the area where fog forms on the ridges. If you look up the coast a bit on the images, you'll see how the clouds sit atop the ridges above the ocean.
Also check out the blue square picture just north of her position on the coast. It is an aerial picture of the Rio Loa taken from offshore. It will give you an excellent idea of the terrain that Island Girl is travelling through right now.
In some areas on top of ridges like these, people build large structures that look very much from a distance like outdoor movie screens except their purpose is to collect dew from these fog clouds.
Island Girl was approximately 147 km (91 miles) south of Iquique last night. She is rapidly approaching the border with Peru.
She roosted on a steep slope overlooking the Pan-American Highway and only 1 km (.6 mile) from the ocean. She could no doubt see the headlights of vehicles during the night and perhaps even hear them.
Her roost was located about 1,286' up the slope according to Google Earth. This is near the area where fog forms on the ridges. If you look up the coast a bit on the images, you'll see how the clouds sit atop the ridges above the ocean.
Also check out the blue square picture just north of her position on the coast. It is an aerial picture of the Rio Loa taken from offshore. It will give you an excellent idea of the terrain that Island Girl is travelling through right now.
In some areas on top of ridges like these, people build large structures that look very much from a distance like outdoor movie screens except their purpose is to collect dew from these fog clouds.
Island Girl was approximately 147 km (91 miles) south of Iquique last night. She is rapidly approaching the border with Peru.
18 April, 2010
Island Girl NNE of Antofagasta on Saturday
On her fifth day of travel, Island Girl apparently continued along the same general migratory pathway, well inland from the coast. She covered 230 km (143 miles) during the day and passed by the city of Antofagasta. Not too likely that she saw it as there is a high ridge east of town that would have blocked her view.
She roosted on what looks like a broad ridgetop with some pretty amazing geology. There are many flow-like alluvial fans in the area. The elevation was still high at around 4,796 feet.
Her roost site was about 71 km (44 miles) north-northeast of Antofagasta and 30 km (19 miles) from the nearest coastline.
She roosted on what looks like a broad ridgetop with some pretty amazing geology. There are many flow-like alluvial fans in the area. The elevation was still high at around 4,796 feet.
Her roost site was about 71 km (44 miles) north-northeast of Antofagasta and 30 km (19 miles) from the nearest coastline.
Island Girl Approaches Antofagasta
On Friday, Island Girl continued flying up the Pacific coast of Chile, covering 254 km (158 miles) as she approached the city of Antofagasta (Sparrow King's home).
As with all of our other tagged falcons, she is making really good time travelling through Chile. She left the Putu area just three days earlier. Most of our falcons have traversed Chile in less than a week. She has travelled 1,114 km (692 miles) so far.
Her track suggests that she is keeping well back from the coast at this point.
For example, she passed the coastal site where Paco was killed two years ago north of Taltal but remained about 25 km (15 miles) inland. Perhaps there are fewer predators in that area. Could this be one reason that they choose the inland pathway?
She roosted on a relatively flat, desert ridge at approximately 6,400 feet in elevation. The Google Earth image does not show any large cliffs here but we found earlier that these images can be deceptive. She could either be roosting directly on the ground (hazardous) or on a small rock not visible in this image.
As with all of our other tagged falcons, she is making really good time travelling through Chile. She left the Putu area just three days earlier. Most of our falcons have traversed Chile in less than a week. She has travelled 1,114 km (692 miles) so far.
Her track suggests that she is keeping well back from the coast at this point.
For example, she passed the coastal site where Paco was killed two years ago north of Taltal but remained about 25 km (15 miles) inland. Perhaps there are fewer predators in that area. Could this be one reason that they choose the inland pathway?
She roosted on a relatively flat, desert ridge at approximately 6,400 feet in elevation. The Google Earth image does not show any large cliffs here but we found earlier that these images can be deceptive. She could either be roosting directly on the ground (hazardous) or on a small rock not visible in this image.
15 April, 2010
Sparrow King's Transmitter Fails After Three Years
For those of you wondering what is happening with Sparrow King, his satellite transmitter finally stopped functioning on 10 March 2010 after 1,105 days (3.02 years).
This is the second best of our transmitters so far, exceeded only by the La Serena bird, a resident Falco peregrinus cassini peregrine of course.
The longevity of Island Girl's transmitter remains to be seen....
This is the second best of our transmitters so far, exceeded only by the La Serena bird, a resident Falco peregrinus cassini peregrine of course.
The longevity of Island Girl's transmitter remains to be seen....
Island Girl Gets Serious
On Wednesday, Island Girl continued north on her spring migration. Based on the signals, she appears to have followed the inland route again and covered 322 km (200 miles) for the day.
She has now left the more heavily vegetated, forested areas behind and transitioned into the southern edge of the Atacama Desert.
She flew past the Illapel region (Chinchilla habitat) and crossed the dry ridges near Ovalle. Later in the day, she flew past one of our favorite places in Chile, the city of La Serena. At this point, she was quite near the La Serena peregrine, our other remaining tagged (but resident) peregrine.
In fact, she roosted only 27.8 km (17 miles) from the La Serena eyrie while sleeping approximately 35 km (22 miles) inland from the beach.
So, at this stage of her migration, she seems to prefer the inland route, which always surprises us. Based on our past experience in this region, we know the habitat is dry, extreme desert with little available prey.
However, it may be that Island Girl, a known coastal hunter, flies nearer to the coast than we know. These comments are based on only three location signals per day. Still, she may exploit the prey resources of the cities and shorelines, hunt and kill there and then, after feeding, fly inland to roost.
We also know from following the La Serena bird that this area of Chile (La Serena) literally abounds with a wide variety and huge number of prey species, particularly pigeons, doves, passerines and shorebirds. There is so much food available here that the La Serena bird has never left her remarkably small home range during the last three years. She doesn't have to. There is always plenty to eat.
Of course, this is also one of the primary factors supporting the northern migrant birds. If there was not a clear advantage to spending their "winters" in South America, they would not have evolved to migrate there. The availabiltiy of abundant prey is certainly one of the strong "incentives".
She has now left the more heavily vegetated, forested areas behind and transitioned into the southern edge of the Atacama Desert.
She flew past the Illapel region (Chinchilla habitat) and crossed the dry ridges near Ovalle. Later in the day, she flew past one of our favorite places in Chile, the city of La Serena. At this point, she was quite near the La Serena peregrine, our other remaining tagged (but resident) peregrine.
In fact, she roosted only 27.8 km (17 miles) from the La Serena eyrie while sleeping approximately 35 km (22 miles) inland from the beach.
So, at this stage of her migration, she seems to prefer the inland route, which always surprises us. Based on our past experience in this region, we know the habitat is dry, extreme desert with little available prey.
However, it may be that Island Girl, a known coastal hunter, flies nearer to the coast than we know. These comments are based on only three location signals per day. Still, she may exploit the prey resources of the cities and shorelines, hunt and kill there and then, after feeding, fly inland to roost.
We also know from following the La Serena bird that this area of Chile (La Serena) literally abounds with a wide variety and huge number of prey species, particularly pigeons, doves, passerines and shorebirds. There is so much food available here that the La Serena bird has never left her remarkably small home range during the last three years. She doesn't have to. There is always plenty to eat.
Of course, this is also one of the primary factors supporting the northern migrant birds. If there was not a clear advantage to spending their "winters" in South America, they would not have evolved to migrate there. The availabiltiy of abundant prey is certainly one of the strong "incentives".
2010 Spring Migration Begins
Island Girl, our last tagged migrant peregrine and the "Earthquake Queen", began her journey north sometime after 1300Z on Tuesday, 13 April. That translates to the morning hours in Chile.
This year, she departed one day after her start last year. She left her area just north of the Putu Dunes and covered about 275 km (171 miles) on the first day and, as usual, generally followed along the Pacific coast.
She flew past many of the places we have worked in or driven through several times including San Antonio, Casablanca, Valparaiso, Vina Del Mar and Quillota. She appears to have crossed the Pan-American Highway just north of Calera before continuing on to roost in the foothills of the coastal range.
Looks like she slept on the north slope of a mountain ridgeline (Cerro Cuajo) in a dry forest only about 2.65 km (1.65 miles) from the highway and south of La Ligua, a place we know well.
She slept inland about 21 km (13 miles) from the beaches of Maitencillo.
As a reminder, many of our satellite transmitters have failed after about a year of service. This unit originally went online on 15 March 2009 after Kathy caught her a second time.
We are hoping that this will be one of the longer lasting units but only time will tell.
This year, she departed one day after her start last year. She left her area just north of the Putu Dunes and covered about 275 km (171 miles) on the first day and, as usual, generally followed along the Pacific coast.
She flew past many of the places we have worked in or driven through several times including San Antonio, Casablanca, Valparaiso, Vina Del Mar and Quillota. She appears to have crossed the Pan-American Highway just north of Calera before continuing on to roost in the foothills of the coastal range.
Looks like she slept on the north slope of a mountain ridgeline (Cerro Cuajo) in a dry forest only about 2.65 km (1.65 miles) from the highway and south of La Ligua, a place we know well.
She slept inland about 21 km (13 miles) from the beaches of Maitencillo.
As a reminder, many of our satellite transmitters have failed after about a year of service. This unit originally went online on 15 March 2009 after Kathy caught her a second time.
We are hoping that this will be one of the longer lasting units but only time will tell.
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