Arena is still holding up in Panama although she is moving short distances around the country. Today, I received this e-mail from our colleague, Marco Saborio, in Costa Rica. He writes....
"The weather here and in Panama has changed in the last two days. We are having rain all around the country. I don't know how this will affect the advance of Arena, my experience with other raptors is that they will stop. However, this morning three Peregrines flew over Kekoldi [a hawkwatching site in Costa Rica] under light rain. I think the rains could stay for the next two days, I hope I'm wrong."
This is a really good example of what we would like to create for this project, a network of raptor people in each of the countries along the Pacific coast of the western hemisphere. Marco has contributed a timely observation about what is currently happening in his geographic area. Arena's slowdown makes more sense to us all now.
It is fun to sit at a computer and speculate endlessly about what is going on with these birds but obviously, nothing beats someone being there "on the ground" with them.
Thanks for the post Marco. We all appreciate it.
27 April, 2007
26 April, 2007
Both Adult Males Nearing Colombia
Both of the tagged males, Seven and Sparrow King, have reached the northern border of Ecuador and should enter Colombia soon. Both seem to be pausing in their journey north and are perhaps "staging" like Arena. Both are in relatively close proximity to one another near Esmeraldas.
As Christian Gonzalez writes from Chile;
"The tiercels (males) were 40 km away from each other in Ecuador, an hour apart really. I know well that place, Esmeraldas , I drove the road where Seven gave a reading before going into the ocean for hunting phalaropes, great place!!!...Also Sparrow King was over the main road into Esmeraldas, they might have seen each other saying ..."Hey!, whatsup you blanquito....hey negrito amigo, you´re carrying a back pack like mine!!!....yeap, ...cool amigo!!!!....keeeek , keeeek!!!"
Pretty exciting to think that they might have seen each other in Ecuador.I was in this area with Steve Herman and his daughter, Sallie, many years ago. It is sub-tropical with dense and heavy vegetation, beautiful, white sandy beaches, palm trees and trade winds coming in off the ocean. Warm, humid and a wonderful place to hang out.
I am surprised that these two males seem to be taking their time to fly north. I had expected that they would make a blue streak to get to their breeding sites as soon as possible. Could this be an indication that they are nesting at very high latitudes? Are their nest sites still covered in snow? Hopefully, we are going to find out soon.
As Christian Gonzalez writes from Chile;
"The tiercels (males) were 40 km away from each other in Ecuador, an hour apart really. I know well that place, Esmeraldas , I drove the road where Seven gave a reading before going into the ocean for hunting phalaropes, great place!!!...Also Sparrow King was over the main road into Esmeraldas, they might have seen each other saying ..."Hey!, whatsup you blanquito....hey negrito amigo, you´re carrying a back pack like mine!!!....yeap, ...cool amigo!!!!....keeeek , keeeek!!!"
Pretty exciting to think that they might have seen each other in Ecuador.I was in this area with Steve Herman and his daughter, Sallie, many years ago. It is sub-tropical with dense and heavy vegetation, beautiful, white sandy beaches, palm trees and trade winds coming in off the ocean. Warm, humid and a wonderful place to hang out.
I am surprised that these two males seem to be taking their time to fly north. I had expected that they would make a blue streak to get to their breeding sites as soon as possible. Could this be an indication that they are nesting at very high latitudes? Are their nest sites still covered in snow? Hopefully, we are going to find out soon.
Houdini and Coquimba
Both Houdini and Coquimba, our two juvenile female peregrines, are remaining in Chile. We are quite interested to see what occurs with these two falcons. Although neither bird has started to migrate, they are still providing us with alot of new information. For the first time, we can look at the movements and range sizes of young peregrines in South America.
Look at the maps for example. Houdini is moving all over the place.First year peregrines need to explore their environments so they can learn where to hunt, where to perch and where to roost at night. They have to learn these things from experience, on their own. So, being similar to many other species, they try out different strategies for surviving. Many work, some don't.You can see, for example, that Houdini is trying out a multitude of different roosting sites all around Antofagasta. She is gaining experience and as she gets older, we expect that the number of these sites will diminish. In my experience, peregrines usually have one main roost that they use habitually.
Coquimba, in contrast to Houdini, appears to have already settled on a single roosting area. She prefers the trees inside a golf course in the town of Coquimbo.
Compare the roosts of the juveniles with that of the adult female, La Serena. She has one relatively discreet roosting area on a mountain ridge outside of the city. She may have established this site during her first year in South America.Since so little information is available regarding juvenile peregines, we simply do not know what to expect from these two birds. Our best bet at this stage is that Coquimba is a northern bird and Houdini is Chilean. But we simply don't know. Even if one is a northern bird, she may not leave Chile for weeks as there is no pressure on her to arrive at and defend a breeding territory in the north.So we are patiently waiting to see what happens.
Look at the maps for example. Houdini is moving all over the place.First year peregrines need to explore their environments so they can learn where to hunt, where to perch and where to roost at night. They have to learn these things from experience, on their own. So, being similar to many other species, they try out different strategies for surviving. Many work, some don't.You can see, for example, that Houdini is trying out a multitude of different roosting sites all around Antofagasta. She is gaining experience and as she gets older, we expect that the number of these sites will diminish. In my experience, peregrines usually have one main roost that they use habitually.
Coquimba, in contrast to Houdini, appears to have already settled on a single roosting area. She prefers the trees inside a golf course in the town of Coquimbo.
Compare the roosts of the juveniles with that of the adult female, La Serena. She has one relatively discreet roosting area on a mountain ridge outside of the city. She may have established this site during her first year in South America.Since so little information is available regarding juvenile peregines, we simply do not know what to expect from these two birds. Our best bet at this stage is that Coquimba is a northern bird and Houdini is Chilean. But we simply don't know. Even if one is a northern bird, she may not leave Chile for weeks as there is no pressure on her to arrive at and defend a breeding territory in the north.So we are patiently waiting to see what happens.
Linda approaching Ecuador
On 22 April, after passing her night at record high altitude, Linda spent the next day gliding down to the coast of Peru, a descent of 4,800 m (16,000'). She did not continue along the crest of the Andes where she would have encountered the highest mountains in Peru, including Huascaran (6768 m or 22,205 feet).
That day, she covered 209 km (130 m) and roosted somewhere on a ridge, probably under 600 m (2,000'), in the foothills of the Andes. We lack a signal for that night, so she may have slept beneath an overhang, preventing the signal from reaching the satellite.
The following day she migrated up the coast to a point just inland from Trujillo, covering 211 km (131 miles). She again roosted on a dry ridgeline at about 630 meters (2,100 feet). This ridge is just south of a major river drainage and not far from the ruins at Chan Chan (see Google Earth icon). The valley has been extensively cultivated to provide food for the population of Trujillo. There are vast agricultural fields sustained, yet again, by water from the Andes. Just as in the Atacama regions of Chile, these areas always support huge numbers of pigeons and doves. It is not difficult to imagine Linda hunting here.
Yesterday, she continued to fly north. It appears that she is continuing to follow an inland line through the foothills of the mountains instead of directly over the coastline. Of course, we can't be certain because of the limited number of signals throughout the day, but the data suggest this route. She covered another 296 km (185 miles), migrating past Chiclayo and Lambayeque. She continued moving inland and eventually roosted in a dry, mountainous area with patches of subtropical forest. She is 120 km (70 miles) inland from the coast and approaching the border of Ecuador.
She is now starting to leave the Atacama Desert.
That day, she covered 209 km (130 m) and roosted somewhere on a ridge, probably under 600 m (2,000'), in the foothills of the Andes. We lack a signal for that night, so she may have slept beneath an overhang, preventing the signal from reaching the satellite.
The following day she migrated up the coast to a point just inland from Trujillo, covering 211 km (131 miles). She again roosted on a dry ridgeline at about 630 meters (2,100 feet). This ridge is just south of a major river drainage and not far from the ruins at Chan Chan (see Google Earth icon). The valley has been extensively cultivated to provide food for the population of Trujillo. There are vast agricultural fields sustained, yet again, by water from the Andes. Just as in the Atacama regions of Chile, these areas always support huge numbers of pigeons and doves. It is not difficult to imagine Linda hunting here.
Yesterday, she continued to fly north. It appears that she is continuing to follow an inland line through the foothills of the mountains instead of directly over the coastline. Of course, we can't be certain because of the limited number of signals throughout the day, but the data suggest this route. She covered another 296 km (185 miles), migrating past Chiclayo and Lambayeque. She continued moving inland and eventually roosted in a dry, mountainous area with patches of subtropical forest. She is 120 km (70 miles) inland from the coast and approaching the border of Ecuador.
She is now starting to leave the Atacama Desert.
Arena pauses on migration
Arena is remaining in Panama for the moment, apparently taking a break from her northern migration.
In 1980, Grainger Hunt, Brenda Johnson and Scott Ward discovered that spring migrant peregrines were pausing at Padre Island, Texas, for varying amounts of time. Using tail-mounted transmitters and a Cessna airplane, Grainger and Brenda found that some individual falcons stayed at the island for up to a month before proceeding north. Grainger theorized that the falcons were fattening up on Gulf migrants so they could produce the best eggs possible. I also thought that there was great value in laying on fat reserves before arriving at their eyries (nests). The females will have to set and incubate/brood for 7 weeks in the arctic, perhaps experiencing the coldest temperatures of their annual cycle. The extra fat could provide more energy to keep them warm during incubation.
So Arena is now "staging" in Panama. Her signals show that she is hanging out at a large bay on the south shore of Panama. It has a strand of sandy beach bordered by an enormous mudfalt, in some places extending a full mile out into the Pacific.
In my experience, extensive mudflats in spring mean large numbers of shorebirds. So we can speculate that she is likely there feeding up on migrants or some other prey species unknown to us at this point.
We'd love to hear from anyone in Panama that might be able to confirm this idea.Also keep in mind that she just migrated nearly 5,000 km and has expended alot of energy to get to Panama. It would be most interesting to compare her weight when we caught her in Chile with her weight now. How much, if any, body mass has she lost on her flight north?
The Google Earth image suggests that she roosted in a grove of trees on a low ridge near, perhaps overlooking, the bay.
In 1980, Grainger Hunt, Brenda Johnson and Scott Ward discovered that spring migrant peregrines were pausing at Padre Island, Texas, for varying amounts of time. Using tail-mounted transmitters and a Cessna airplane, Grainger and Brenda found that some individual falcons stayed at the island for up to a month before proceeding north. Grainger theorized that the falcons were fattening up on Gulf migrants so they could produce the best eggs possible. I also thought that there was great value in laying on fat reserves before arriving at their eyries (nests). The females will have to set and incubate/brood for 7 weeks in the arctic, perhaps experiencing the coldest temperatures of their annual cycle. The extra fat could provide more energy to keep them warm during incubation.
So Arena is now "staging" in Panama. Her signals show that she is hanging out at a large bay on the south shore of Panama. It has a strand of sandy beach bordered by an enormous mudfalt, in some places extending a full mile out into the Pacific.
In my experience, extensive mudflats in spring mean large numbers of shorebirds. So we can speculate that she is likely there feeding up on migrants or some other prey species unknown to us at this point.
We'd love to hear from anyone in Panama that might be able to confirm this idea.Also keep in mind that she just migrated nearly 5,000 km and has expended alot of energy to get to Panama. It would be most interesting to compare her weight when we caught her in Chile with her weight now. How much, if any, body mass has she lost on her flight north?
The Google Earth image suggests that she roosted in a grove of trees on a low ridge near, perhaps overlooking, the bay.
23 April, 2007
Linda, a New Altitude Record for Roosting?
Linda flew another 200 miles yesterday and continued on her path through the altiplano of the central Andes. She passed west of Lago Junin, the largest lake in Peru and a well-known birding location. It is home to one of the rarest birds on earth, the Junin Grebe. Elevation there is 4,082 m. or 13,500 feet.
Linda is now approaching the Cordillera Huayhuash which has the highest mountains in Peru, including Cerro Yerupaja (6,634 m or 21,892 feet) and Huascaran (6,768 m. or 22,334 feet). So she is moving through some pretty high country.
When we checked her positions today, we found that she had roosted last night at an elevation of approximately 15,867 feet. We obtained this value from the Google Earth elevations as the GPS transmitter altimeter data has not been reliable lately.
This is impressive new data and we believe that it may be a new altitude record for a roosting peregrine, certainly for the Americas and possibly the world. It may be there are higher roosts in the central plateau of Tibet and the Himalayas but at this time, we are unaware of any that are documented.
I can only imagine what she is seeing from that height and location. It must be absolutely spectacular.
It is also impressive that she is covering so much distance at this altitude, despite the thinner air and reduced oxygen content.
Linda is now approaching the Cordillera Huayhuash which has the highest mountains in Peru, including Cerro Yerupaja (6,634 m or 21,892 feet) and Huascaran (6,768 m. or 22,334 feet). So she is moving through some pretty high country.
When we checked her positions today, we found that she had roosted last night at an elevation of approximately 15,867 feet. We obtained this value from the Google Earth elevations as the GPS transmitter altimeter data has not been reliable lately.
This is impressive new data and we believe that it may be a new altitude record for a roosting peregrine, certainly for the Americas and possibly the world. It may be there are higher roosts in the central plateau of Tibet and the Himalayas but at this time, we are unaware of any that are documented.
I can only imagine what she is seeing from that height and location. It must be absolutely spectacular.
It is also impressive that she is covering so much distance at this altitude, despite the thinner air and reduced oxygen content.
Arena sizing things up?
From the signal it appears that Arena spent the night roosting in a tree overlooking the Caribbean Sea. She crossed the Panama Canal yesterday and is just west of the city of Colon, not far from the famous Gatun Locks.
At this point, her northern progress is blocked by the Caribbean. Since she hasn't moved very far in the last two days, it is tempting to speculate that she has been resting up for a major water crossing. We are wondering if she is going to simply head straight north over the sea.
Peregrines are capable of the most amazing over-water travels. For example, a migrant adult was known to have "wintered" every year in the Galapagos Islands, 725 miles offshore from Costa Rica. There is only one island, Cocos Island, between Costa Rica and the Galapagos Islands as a mid-point landfall. The distance from Salinas, Ecuador is 580 miles across the Pacific.
Last year in April, I saw an adult female peregrine fly right in front of me on the Kona side of the big island of Hawaii, 2,330 miles off of the coast of California. Peregrines have been reported from Hawaii many times.
So Arena may be poised for such a flight or she may continue up the Central American corridor, perhaps passing near the Kekoldi hawkwatch site in Costa Rica. Our colleague, Marco Saborio, will be looking for her in his country. Good luck Marco!
At this point, her northern progress is blocked by the Caribbean. Since she hasn't moved very far in the last two days, it is tempting to speculate that she has been resting up for a major water crossing. We are wondering if she is going to simply head straight north over the sea.
Peregrines are capable of the most amazing over-water travels. For example, a migrant adult was known to have "wintered" every year in the Galapagos Islands, 725 miles offshore from Costa Rica. There is only one island, Cocos Island, between Costa Rica and the Galapagos Islands as a mid-point landfall. The distance from Salinas, Ecuador is 580 miles across the Pacific.
Last year in April, I saw an adult female peregrine fly right in front of me on the Kona side of the big island of Hawaii, 2,330 miles off of the coast of California. Peregrines have been reported from Hawaii many times.
So Arena may be poised for such a flight or she may continue up the Central American corridor, perhaps passing near the Kekoldi hawkwatch site in Costa Rica. Our colleague, Marco Saborio, will be looking for her in his country. Good luck Marco!
Linda and Arena - April 23rd
Linda continues to travel up the spine of the Andes Mountains. Yesterday she flew 254 km (158 miles) over the high, dry mountains of the Puna region of Peru. The transmitter indicates that she roosted on a ridge overlooking a deep valley about 18 miles NW of the famous town of Ayacucho, elevation 3,000 meters (9,000 feet). To see the habitat, you can click on the symbols at Ayacucho on Google Earth. You will see brown, dry, rolling hills with little vegetation, again perfect hunting habitat for falcons.
Linda is moving closer to the east side of the Andes now and is only about 60 km (40 miles) from the Amazon basin. You can see the rapid transition to the green tropical forests on the maps.
She is currently about 2,400 km (1,500 miles) behind Arena.
Arena flew 157 km (98 miles) yesterday. She passed along the southern edge of the famous Darien Gap of Panama, the wild and roadless area that still effectively separates the two continents. According to the GPS signal, she winged her way over the eastern outskirts of Panama City at an altitude of 80 meters (250') .
Panama can be incredibly hot and humid. And, as I think about it, it is possible that this may be the warmest area that she will encounter on her migration north. The heat and humidity may have something to do with the relatively short distance that she traveled today.
Arena eventually roosted in the forest overlooking a large lake – Madden Lake. She slept about 20 miles east of the Panama Canal and just south of the Caribbean Sea. I wish I could see exactly what her roost looked like. Was it a tree, cliff, power tower, antenna or what?
We don't think about this much but here she is, dropping out of the sky, looking for a safe place to sleep. She is in a new location, a new habitat, new environmental conditions, new sounds, new predators, new types of trees. And she has to select a roost where she will be safe at night. Maybe the best analogy for us to think about would be arriving in an entirely new country at dusk and trying to find a safe place to stay.
She also has to avoid an entirely new host of predators, many of them arboreal. We're talking everything from snakes and owls to Jaguars. This is one of the reasons that biologists consider migration to be so "expensive". It costs the bird energy to make the long migration and it also exposes them to a much greater risk, as you can understand by imagining Arena tucking up into some giant tree.
In contrast, the peregrines living here in my home town of Seattle (47 N. latitude) don't migrate. They remain here all year and so they are not exposed to the same dangers and costs as Arena.
Her flight path has continued to trend to the northwest but if she wants to migrate up through Central America, she will have to alter her course today. I expect that she will back-track and fly WSW from here. Now let's see what she really does....
Linda is moving closer to the east side of the Andes now and is only about 60 km (40 miles) from the Amazon basin. You can see the rapid transition to the green tropical forests on the maps.
She is currently about 2,400 km (1,500 miles) behind Arena.
Arena flew 157 km (98 miles) yesterday. She passed along the southern edge of the famous Darien Gap of Panama, the wild and roadless area that still effectively separates the two continents. According to the GPS signal, she winged her way over the eastern outskirts of Panama City at an altitude of 80 meters (250') .
Panama can be incredibly hot and humid. And, as I think about it, it is possible that this may be the warmest area that she will encounter on her migration north. The heat and humidity may have something to do with the relatively short distance that she traveled today.
Arena eventually roosted in the forest overlooking a large lake – Madden Lake. She slept about 20 miles east of the Panama Canal and just south of the Caribbean Sea. I wish I could see exactly what her roost looked like. Was it a tree, cliff, power tower, antenna or what?
We don't think about this much but here she is, dropping out of the sky, looking for a safe place to sleep. She is in a new location, a new habitat, new environmental conditions, new sounds, new predators, new types of trees. And she has to select a roost where she will be safe at night. Maybe the best analogy for us to think about would be arriving in an entirely new country at dusk and trying to find a safe place to stay.
She also has to avoid an entirely new host of predators, many of them arboreal. We're talking everything from snakes and owls to Jaguars. This is one of the reasons that biologists consider migration to be so "expensive". It costs the bird energy to make the long migration and it also exposes them to a much greater risk, as you can understand by imagining Arena tucking up into some giant tree.
In contrast, the peregrines living here in my home town of Seattle (47 N. latitude) don't migrate. They remain here all year and so they are not exposed to the same dangers and costs as Arena.
Her flight path has continued to trend to the northwest but if she wants to migrate up through Central America, she will have to alter her course today. I expect that she will back-track and fly WSW from here. Now let's see what she really does....
21 April, 2007
Roosting on a drainpipe
We received an e-mail today from a friend of Christian in Antofagasta named Mario Quiroz. He sent this picture of an adult female peregrine perched on a drainpipe on his condominium. She is sitting just outside of the window of his son's room. This is a typical roost, or nighttime perch, and demonstrates how much peregrines have adapted to cities in South America. I have seen the exact same type of perch used in both Ecuador and Peru. It is the perfect diameter for their feet, it is located at a safe and inaccessible point high up on a building, it is sheltered from the wind, and it has a great vantage point for hunting.When the team was in Antofagasta in late February, Christian took us to this site after dinner but the falcon was sleeping elsewhere that evening.
April 21st update
Arena covered 263 km (164 miles) yesterday and officially left South America. She continued to fly well into Panama and the signal shows that she was still migrating after 5 PM local time. You can see that location where she was about a mile offshore and still heading north.
She has made her "decision" to continue migrating up through Central America, at least for awhile, at this point.
If you have never been there, Panama is shaped a bit like a crescent moon on its side. It is actually situated on an east-west axis, not north-south as many people expect. To continue flying north, Arena will actually have to fly west for a bit.
Let's see if she continues flying up the coastline or does a short-cut across the Pacific to the Pearl Islands.
Linda has left the coastal terrace and moved up into the high country of the Andes. She roosted on a ridgeline above a river valley last night. If you have Google Earth, zoom in to this area and you will see why she is there. It is covered with high altitude lakes and ponds. This is very open country and is ideal habitat for peregrines to hunt. These abundant water sources support high populations of prey species. It is likely that some are migrating north with the falcons. Click on some the blue circle icons to see photographs of this remarkable area.
The transmitters are confirming that the high country or Puna area of Peru seems to be quite important for migrating peregrines.
Seven has returned to the coastal route and is moving north at an accelerated rate. He is near Ecuador and should arrive there today.
She has made her "decision" to continue migrating up through Central America, at least for awhile, at this point.
If you have never been there, Panama is shaped a bit like a crescent moon on its side. It is actually situated on an east-west axis, not north-south as many people expect. To continue flying north, Arena will actually have to fly west for a bit.
Let's see if she continues flying up the coastline or does a short-cut across the Pacific to the Pearl Islands.
Linda has left the coastal terrace and moved up into the high country of the Andes. She roosted on a ridgeline above a river valley last night. If you have Google Earth, zoom in to this area and you will see why she is there. It is covered with high altitude lakes and ponds. This is very open country and is ideal habitat for peregrines to hunt. These abundant water sources support high populations of prey species. It is likely that some are migrating north with the falcons. Click on some the blue circle icons to see photographs of this remarkable area.
The transmitters are confirming that the high country or Puna area of Peru seems to be quite important for migrating peregrines.
Seven has returned to the coastal route and is moving north at an accelerated rate. He is near Ecuador and should arrive there today.
20 April, 2007
Arena and Sparrow King
Arena arrived back on the coast of Colombia after an impressive over-water crossing. We can't be certain exactly where she made her landfall but even a minimum distance (a 90 degree turn east from her last oceanic point) would be 131 miles. She may have gone as far as 170 miles over the ocean but we can't be certain because of the limited number of signals.
We are watching closely as she approaches Panama. We expect that this will be one of her first major "decision points" en route north. The next week or so is particularly critical in forecasting her destination.
Will she continue up the west coast of Central America? Will she veer to the east through Colombia? If she travels through Central America, will she jump off at the Yucatan and head for the east coast of the US? Will she proceed up through Padre Island, Texas, as so many spring migrant peregrines do? And if so, where does she go from there?
We are all awaiting the next signals from today. They should be here this afternoon.
Sparrow King is moving north like a rocket. He is now in Ecuador, and may have spent the night near Guayaquil. This is the home of Nancy Hilgert, the leading peregrine expert in Ecuador. She has documented many peregrines "wintering" in her city over the years. She described how peregrines there hunt bats over the city in the evening and I had the pleasure of observing this behavior several times. The falcons simply fly out over the Rio Guayas and, seemingly without effort, grab the bats out of the air.
Sparrow king continues to outpace the other adult male, Seven, by a large margin.
Don McCall has put together the following stats comparing the migrations of Arena and Sparrow King. Keep in mind that Arena began moving 9 days before Sparrow King.
We are watching closely as she approaches Panama. We expect that this will be one of her first major "decision points" en route north. The next week or so is particularly critical in forecasting her destination.
Will she continue up the west coast of Central America? Will she veer to the east through Colombia? If she travels through Central America, will she jump off at the Yucatan and head for the east coast of the US? Will she proceed up through Padre Island, Texas, as so many spring migrant peregrines do? And if so, where does she go from there?
We are all awaiting the next signals from today. They should be here this afternoon.
Sparrow King is moving north like a rocket. He is now in Ecuador, and may have spent the night near Guayaquil. This is the home of Nancy Hilgert, the leading peregrine expert in Ecuador. She has documented many peregrines "wintering" in her city over the years. She described how peregrines there hunt bats over the city in the evening and I had the pleasure of observing this behavior several times. The falcons simply fly out over the Rio Guayas and, seemingly without effort, grab the bats out of the air.
Sparrow king continues to outpace the other adult male, Seven, by a large margin.
Don McCall has put together the following stats comparing the migrations of Arena and Sparrow King. Keep in mind that Arena began moving 9 days before Sparrow King.
Days migrating | Distance | Avg. per day | |
Arena | 18 | 4,337 km | 241 km |
Sparrow | 9 | 2,722 km | 302 km |
19 April, 2007
April 18th update on 4 migrating falcons
Four of the radio-tagged falcons are migrating at this time, 2 adult females (Arena and Linda) and two adult males (Seven and Sparrow King). One adult female (La Serena) and two immature females (Houdini and Coquimba) still remain on their austral ranges.
Arena
Arena continues to move north at a steady pace. She has now passed over the equator and left the southern hemisphere behind. She entered Colombia still following the coastal route. Don comments that she probably had a good opportunity to see the volcanic eruption that took place there yesterday.
She has migrated through four countries so far with all of the Central American countries coming up soon. We are anticipating her arrival in Panama with great interest. This country is a major crossroads for all raptors migrating to and from South America. It is here that we may first be able to forecast her general route north.
At this point, no one knows where she nests. We suspect it will be in the Arctic but we don't know for certain at this time.
As she approaches Panama, she will either continue up through the funnel of Central America or she will veer east out into the Caribbean Islands. We tend to think that the Caribbean route will indicate an easterly orientation (e.g. Greenland) and a Central American route could lead to western Canada or Alaska.
Of course, she does not know all of this and will choose to go wherever she wants.
Arena spent the night on Isla Gorgona, approximately 30 km offshore of the Colombian coast. This island was a former penal colony but was recently converted into a park by the Colombian government. It is famous for its subtropical forests, coral reefs and poisonous snakes. Tourists can go there by boat or plane but travel on the island is pretty much restricted. Here is a quote from the web...
"There are several species of poisonous snakes on the island. Walking to playa Blanca and further is only allowed with guide and rubber boots (You can rent them at restaurant for COP$7000). After 5pm the it's advisable to wear rubber boots as well and use torches."
Think I'll pass on a visit.
This morning Arena flew directly north out over the Pacific Ocean. How does she know where to go? Our last signal shows her flying at 50 km/h about 50 km offshore, enroute to Panama. Does this commitment to a western route indicate she will continue west when she hits the US?
The over-water distance from Gorgona to the peninsula west of Panama City is about 330 miles. She could conceivably cover this distance but I think that it is more likely that she will put into shore somewhere in Colombia. It is always fun to speculate. Now let's see what she really does.
Remarkable bird and a great teacher...
Linda
Linda is now approaching the Peruvian border. She covered 312 km yesterday and is seriously migrating at this time. As we expected, she is following the coastal route.
Seven
Seven has moved back up into the Andes on his migration north. He has passed by Lima and continues to move north at high elevation. There are many lakes and rivers in this region with abundant prey for a migrant falcon.
Sparrow King
Sparrow King is moving at a much faster rate than Seven and is still following the coastal route. He should arrive in Ecuador soon.
Arena
Arena continues to move north at a steady pace. She has now passed over the equator and left the southern hemisphere behind. She entered Colombia still following the coastal route. Don comments that she probably had a good opportunity to see the volcanic eruption that took place there yesterday.
She has migrated through four countries so far with all of the Central American countries coming up soon. We are anticipating her arrival in Panama with great interest. This country is a major crossroads for all raptors migrating to and from South America. It is here that we may first be able to forecast her general route north.
At this point, no one knows where she nests. We suspect it will be in the Arctic but we don't know for certain at this time.
As she approaches Panama, she will either continue up through the funnel of Central America or she will veer east out into the Caribbean Islands. We tend to think that the Caribbean route will indicate an easterly orientation (e.g. Greenland) and a Central American route could lead to western Canada or Alaska.
Of course, she does not know all of this and will choose to go wherever she wants.
Arena spent the night on Isla Gorgona, approximately 30 km offshore of the Colombian coast. This island was a former penal colony but was recently converted into a park by the Colombian government. It is famous for its subtropical forests, coral reefs and poisonous snakes. Tourists can go there by boat or plane but travel on the island is pretty much restricted. Here is a quote from the web...
"There are several species of poisonous snakes on the island. Walking to playa Blanca and further is only allowed with guide and rubber boots (You can rent them at restaurant for COP$7000). After 5pm the it's advisable to wear rubber boots as well and use torches."
Think I'll pass on a visit.
This morning Arena flew directly north out over the Pacific Ocean. How does she know where to go? Our last signal shows her flying at 50 km/h about 50 km offshore, enroute to Panama. Does this commitment to a western route indicate she will continue west when she hits the US?
The over-water distance from Gorgona to the peninsula west of Panama City is about 330 miles. She could conceivably cover this distance but I think that it is more likely that she will put into shore somewhere in Colombia. It is always fun to speculate. Now let's see what she really does.
Remarkable bird and a great teacher...
Linda
Linda is now approaching the Peruvian border. She covered 312 km yesterday and is seriously migrating at this time. As we expected, she is following the coastal route.
Seven
Seven has moved back up into the Andes on his migration north. He has passed by Lima and continues to move north at high elevation. There are many lakes and rivers in this region with abundant prey for a migrant falcon.
Sparrow King
Sparrow King is moving at a much faster rate than Seven and is still following the coastal route. He should arrive in Ecuador soon.
17 April, 2007
Differences in transmitters
Please remember that the data for the two males comes from standard PTT transmitters. These units are programmed to send out signals every two to three days and are not as accurate as the GPS PTTs on the five females. As a result, it can appear as if the two males are following routes and traveling distances that do not represent their true paths.
For example, Lindsay Oaks pointed out to me today that it appears on the map as if Sparrow King did an over-water crossing from Chile to Peru. The lines connecting his points suggest that to be true. However, because of the PTT characteristics, we cannot say exactly which routes either male is selecting on the way north, but only where a particular male was at the time of a signal. In short, the lines connecting the male points may be misleading.
In contrast, the five female GPS units normally produce three signals per day that are accurate to within plus or minus 20 meters of the transmitter. In all cases the lines connecting the dots may not reflect reality.
For example, Lindsay Oaks pointed out to me today that it appears on the map as if Sparrow King did an over-water crossing from Chile to Peru. The lines connecting his points suggest that to be true. However, because of the PTT characteristics, we cannot say exactly which routes either male is selecting on the way north, but only where a particular male was at the time of a signal. In short, the lines connecting the male points may be misleading.
In contrast, the five female GPS units normally produce three signals per day that are accurate to within plus or minus 20 meters of the transmitter. In all cases the lines connecting the dots may not reflect reality.
16 April, 2007
"Arena" is flying fast
Don McCall reports that Arena is moving hard. She covered 322 miles today and is almost halfway across Ecuador. This is a record for her thus far. Must be feeling that migratory urge....
It appears that Arena flew well out over the Pacific Ocean today and across the Gulf of Guayaquil. It looks like she passed relatively close to my old study area at Salinas. In speaking with peregrine expert Nancy Hilgert on the phone today in Ecuador, she thought that Arena might go through Salinas. Looks like she was correct. I had expected the Arena to fly up the central valley of Ecuador along the Rio Guayaquil but she did a bit of an over-water dog-leg instead. These GPS units are SO TOTALLY COOL!
Mark Prostor noticed that when Arena flew across the Gulf of Guayaquil about 50 miles offshore, the data tag read that she was flying at 2,000' AMSL (above mean sea level) at 40 MPH.
From her last signal around 3 PM Ecuador time, she appears to have been flying over an assemblage of commercial shrimp ponds at the west end of the Bahia de Caraquez (check out the Google Earth photos of the beaches to the west). In Ecuador, these ponds support high numbers of shorebirds which forage and roost along the margins of the impoundments. Arena might have been hunting after her record flight.
She is currently in an area of heavy mangrove trees which begin at the southern boundary of Ecuador. The last signal (11 PM local time) from Arena indicates that she roosted at an inland tropical forest site among the coastal hills of Ecuador. It seems likely that this is the first time she has roosted in a forest since the fall migration last year, probably in October. At any rate, she successfully made it through the Atacama Desert once again.
It appears that Arena flew well out over the Pacific Ocean today and across the Gulf of Guayaquil. It looks like she passed relatively close to my old study area at Salinas. In speaking with peregrine expert Nancy Hilgert on the phone today in Ecuador, she thought that Arena might go through Salinas. Looks like she was correct. I had expected the Arena to fly up the central valley of Ecuador along the Rio Guayaquil but she did a bit of an over-water dog-leg instead. These GPS units are SO TOTALLY COOL!
Mark Prostor noticed that when Arena flew across the Gulf of Guayaquil about 50 miles offshore, the data tag read that she was flying at 2,000' AMSL (above mean sea level) at 40 MPH.
From her last signal around 3 PM Ecuador time, she appears to have been flying over an assemblage of commercial shrimp ponds at the west end of the Bahia de Caraquez (check out the Google Earth photos of the beaches to the west). In Ecuador, these ponds support high numbers of shorebirds which forage and roost along the margins of the impoundments. Arena might have been hunting after her record flight.
She is currently in an area of heavy mangrove trees which begin at the southern boundary of Ecuador. The last signal (11 PM local time) from Arena indicates that she roosted at an inland tropical forest site among the coastal hills of Ecuador. It seems likely that this is the first time she has roosted in a forest since the fall migration last year, probably in October. At any rate, she successfully made it through the Atacama Desert once again.
Linda has started her migration
Our fourth peregrine, the adult female named "Linda", left the Antofagasta area this afternoon and flew 84 miles north. It appears that she is now migrating. We caught her hunting at the same location and on the same day as Sparrow King.
Linda appears to have roosted in the desert 80 miles north of her capture site in Antofagasta. Her last signal was received at 0100 local time. This also strongly suggests that she is moving north. Her first day's movement is very different from Arena who flew 300 miles + on that first flight. Perhaps they started north at different times of the day.
It is not difficult to imagine that someday, the way technology is advancing, we will be able to get signals from migrant peregrines on an hourly basis.
Linda appears to have roosted in the desert 80 miles north of her capture site in Antofagasta. Her last signal was received at 0100 local time. This also strongly suggests that she is moving north. Her first day's movement is very different from Arena who flew 300 miles + on that first flight. Perhaps they started north at different times of the day.
It is not difficult to imagine that someday, the way technology is advancing, we will be able to get signals from migrant peregrines on an hourly basis.
A bit more on "Seven"
The PTT signals indicate that Seven has moved down from the high Andes and is back on the coast of Chile. He is in the rugged desert area south of Arica. This region is known for its many earthquakes and has several deeply-cut river canyons along the coastal terrace. Zoom in on the river canyon just north of the coastal town of Pisagua (just west of the last fix). You can see where the Pan-Am highway crosses the canyon well upstream from the coast.
We don't know why Seven returned to the Pacific coast but we should be able to see if he continues along this route.
Little is known about the migration of peregrine tiercels, or males, especially the ones "wintering" in South America. We are most interested to see how much, if any, their behavior varies from the females. Since we are dealing with PTTs, we can't get the same precise fixes as the GPS females but we are still able to obtain some idea of their movements.
Although Seven "wintered" much further south and even left earlier than the other male, Sparrow King, he is not progressing north as rapidly. The comparisons of these two males continues to be fascinating and instructive to us.
Our web guys, Don, Mark and Pat will be happy when and if more of the females start north as it is challenging to extrapolate accurate data from the PTT signals. The GPS data are hard to beat."
We don't know why Seven returned to the Pacific coast but we should be able to see if he continues along this route.
Little is known about the migration of peregrine tiercels, or males, especially the ones "wintering" in South America. We are most interested to see how much, if any, their behavior varies from the females. Since we are dealing with PTTs, we can't get the same precise fixes as the GPS females but we are still able to obtain some idea of their movements.
Although Seven "wintered" much further south and even left earlier than the other male, Sparrow King, he is not progressing north as rapidly. The comparisons of these two males continues to be fascinating and instructive to us.
Our web guys, Don, Mark and Pat will be happy when and if more of the females start north as it is challenging to extrapolate accurate data from the PTT signals. The GPS data are hard to beat."
Some comments about Arena
Arena is now approaching Ecuador. She will soon be crossing the equator, the geographic midpoint of our planet.
She is also leaving the familiar Atacama Desert where she has been living for the last five months. She has been existing in an extremely dry desert habitat with lots of sunshine, open ground for hunting, abundant prey and little in the way of energetic requirements because of the heat.
Now she will be entering a tropical forest environment where everything will be different, rainfall, humidity, vegetation, new (and vulnerable) roost sites and prey species to some extent. She is going to be moving through most of the Central American countries before arriving in Mexico and the United States.
So things are going to change rapidly for her as she progresses north. You can see the shift in vegetation (brown to green) on the Google Earth maps beginning at the border.
The last of the Atacama exists on a remarkable peninsula west of Guayaquil at Salinas. I had the privilege to work on peregrines there in the late 1980's and found that it was loaded with "wintering" peregrines from the north. We identified over 20 individual falcons and encountered "winter pair behavior" in most of them. We observed adult males and females perching together, hunting together, and sharing kills but never copulation. The question has always been could these be the same pairs from the Arctic or are they pairs of convenience? We hope to answer these questions in the future through the use of these wonderful GPS transmitters.
She is also leaving the familiar Atacama Desert where she has been living for the last five months. She has been existing in an extremely dry desert habitat with lots of sunshine, open ground for hunting, abundant prey and little in the way of energetic requirements because of the heat.
Now she will be entering a tropical forest environment where everything will be different, rainfall, humidity, vegetation, new (and vulnerable) roost sites and prey species to some extent. She is going to be moving through most of the Central American countries before arriving in Mexico and the United States.
So things are going to change rapidly for her as she progresses north. You can see the shift in vegetation (brown to green) on the Google Earth maps beginning at the border.
The last of the Atacama exists on a remarkable peninsula west of Guayaquil at Salinas. I had the privilege to work on peregrines there in the late 1980's and found that it was loaded with "wintering" peregrines from the north. We identified over 20 individual falcons and encountered "winter pair behavior" in most of them. We observed adult males and females perching together, hunting together, and sharing kills but never copulation. The question has always been could these be the same pairs from the Arctic or are they pairs of convenience? We hope to answer these questions in the future through the use of these wonderful GPS transmitters.
Yes, Sparrow King is migrating
Don McCall has confirmed that the second adult male peregrine, Sparrow King, is migrating north at this time.
Yesterday, he was in the vicinity of the internationally famous Nazca Lines south of Lima. Several hundred geo-glyphs were created between 200 BC and 700 AD by the indigenous Nazca people and depict a variety of animals (birds, insects and humans) and geometric shapes. If you click on the Google Earth symbols (blue circles with a cross), you can see many of them drawn onto the surface of the ground.
It is ironic that many centuries ago people went to such a tremendous amount of effort to create these remarkable symbols without knowing that centuries later, thousands of people all over the world would be looking at them via satellite photos from space.
Yesterday, he was in the vicinity of the internationally famous Nazca Lines south of Lima. Several hundred geo-glyphs were created between 200 BC and 700 AD by the indigenous Nazca people and depict a variety of animals (birds, insects and humans) and geometric shapes. If you click on the Google Earth symbols (blue circles with a cross), you can see many of them drawn onto the surface of the ground.
It is ironic that many centuries ago people went to such a tremendous amount of effort to create these remarkable symbols without knowing that centuries later, thousands of people all over the world would be looking at them via satellite photos from space.
15 April, 2007
Is Sparrow King on the move?
We received a good signal from the second adult male, Sparrow King, on the 13th of April. It indicated that he had uncharacteristically flown north about 23 miles from his capture site at Antofagasta. We thought this might be the start of his migration but weren’t certain.
Today, we have obtained several new fixes from his PTT. Remember that the male PTT units only send a signal every two or three days and that they lack a GPS chip. To save on weight, they are simply not as accurate as the other transmitters.
The quality of today’s signal data is not the best. The last six signals have been category “0”. The most accurate signals are “3’s”. The 0 category indicates that we have obtained signals from only 2 satellites rather than three or more, so the accuracy can be limited.
What is exciting, however, is that all three of the last signals are from the Nazca area of Peru, around 700 miles north of Antofagasta via the coastal dogleg route! (see map)
We would be more skeptical if we had only one signal from there but to get 3 from the same general area is more tantalizing. If they are accurate (still a very big IF at this point), then this male has flown 700 miles in two days, a remarkable feat. We want to get some more category 3 signals before we can be certain of his location.
We are putting this information on the web now because we wanted to show everyone that sometimes we are confronted with uncertainty in our work. It is not all cut and dried, at least not with PTTs. This is typical of field biology. At the same time this could be an exciting start to his migration and we wanted to alert everyone of this possibility.
Arena, for example, moved over 300 miles on her first day, so 700 miles is not out of the realm of possibility for the male, just very impressive.
However, to be on the safe side, let’s wait until we get a really good fix before we state this as a fact. So remain a bit skeptical and stay tuned…
Today, we have obtained several new fixes from his PTT. Remember that the male PTT units only send a signal every two or three days and that they lack a GPS chip. To save on weight, they are simply not as accurate as the other transmitters.
The quality of today’s signal data is not the best. The last six signals have been category “0”. The most accurate signals are “3’s”. The 0 category indicates that we have obtained signals from only 2 satellites rather than three or more, so the accuracy can be limited.
What is exciting, however, is that all three of the last signals are from the Nazca area of Peru, around 700 miles north of Antofagasta via the coastal dogleg route! (see map)
We would be more skeptical if we had only one signal from there but to get 3 from the same general area is more tantalizing. If they are accurate (still a very big IF at this point), then this male has flown 700 miles in two days, a remarkable feat. We want to get some more category 3 signals before we can be certain of his location.
We are putting this information on the web now because we wanted to show everyone that sometimes we are confronted with uncertainty in our work. It is not all cut and dried, at least not with PTTs. This is typical of field biology. At the same time this could be an exciting start to his migration and we wanted to alert everyone of this possibility.
Arena, for example, moved over 300 miles on her first day, so 700 miles is not out of the realm of possibility for the male, just very impressive.
However, to be on the safe side, let’s wait until we get a really good fix before we state this as a fact. So remain a bit skeptical and stay tuned…
12 April, 2007
"Seven" and "Arena" are both migrating now
We hope that you are enjoying the falcon migration as much as we are. As peregrine biologists, it is gratifying for us to see where these birds are going, especially in such detail. A lot of people have wanted to learn more about this movement in South America for a very long time. And, as several of you have commented, we did not expect to live long enough to see this happen.
Because of the “marriage” of two recent technologies, miniaturized GPS satellite transmitters and Internet-based satellite imagery maps, we are discovering details about peregrines that have not been possible before. For the team, it is a privilege to witness this.
This is the first time that such detailed GPS data has been available for arctic peregrines traveling between South and North America.
Arena
Arena was the first tagged falcon to begin migrating north. She departed on 2 April 2007 and her first flight extended just over 300 miles north to Antofagasta. We had not expected such an “energetic” first flight. We figured she would slowly work her way into it and increase her distances each day as she got in shape. But that first flight has been the longest so far. She got off to a good start.
Her route has generally followed the Pacific coastline north. However, as several of you have noticed, she often migrated well inland from the shoreline. We thought she would stay right along the beaches to take advantage of the shorebird and seabird populations for food. But it is likely that the onshore Pacific winds are aiding and influencing her inland flights as they flow across the coastal terrace and up into the Andean foothills.
Christian Gonzalez identified her first stopover point (roost) as Hornitos, a beach known to support large numbers of Sanderlings. He has observed peregrines there before.
Later Arena flew past some northern Chile geo-glyphs etched into the desert sands.
If you have not noticed, Google Earth displays these little blue circle/cross icons. If you click on them, you will see a picture of the area, including some of these glyphs. Some of these shots are remarkable and we strongly suggest that you check them out. It provides an excellent “feel’ for the area. In order to see these features of Google Earth you have to turn on certain layers (this is on the lower left side of the screen) - the image at right shows the layers we think you might want to turn on.
Christian comments that he has visited many of these inland areas of Chile and that most are loaded with pigeons, doves and passerines.
Arena passed into Peru along the coast near Tacna, an area that Tom Maechtle and I had trapped back in the 1980’s. We caught 23 peregrines during that trip to Peru and so we know that the peregrine density along this coast is high.
In the Atacama Desert of Peru, most of the human activity and settlements are associated with the major river drainages extending down from the Andes. You can clearly see this via Google Earth. These drainages funnel the melting snow waters which support the local agriculture. Cotton was a major crop when we were there in the past.
As in the Chilean Atacama, these settlements support high numbers of prey species including Rock Pigeons and a variety of doves and passerines. Shorebirds are always present along the beaches.
As Arena varied her route between coast and inland, she passed over the Pan-American Highway several times. It is visible as the main road roughly paralleling the shoreline.
It is becoming clear that this falcon migrates in a series of starts and stops. She may stay at one location for over a day, perhaps feeding, resting and augmenting her fat reserves. Her flight north is not a daily process.
We alerted our peregrine colleague, Oscar Beingolea of Lima, Peru, that Arena was on her way north and he has been providing a lot of comments along the way. For example, those long assemblages of white buildings that many of you are seeing are chicken farms, providing meat to the Lima markets. As Oscar explained to us many years ago, these are always excellent places to see peregrines. The readily available supply of bird food attracts prey species of all types which in turn attracts the falcons.
Just before flying over Lima, Arena apparently slept on a headland along the seacoast at the famous town of Pucusana. This is a major fishing (and tourist) village just south of Lima. I encourage you all to zoom in to see the flotilla of boats in the harbor. Check out the picture icons to have a look at this beautiful town.
Last time I was there with Oscar, a Belgian cetologist that I met had just described a new species of beaked whale that occurred offshore from this area.
As an example of this remarkable Google Earth technology, I’d like to point out something. From the roost site dot at Pucusana (south of Lima), look just south a hundred meters or so and you will see a deep cut extending north into the headland. There are actually two. Follow the right cut east (right) and if you zoom in closely, you can see that it has formed a sea-cave that goes underground and comes out on the other side in a small, foaming bay in town. Very cool!
Anyway, Arena continues her migration north and we expect her to arrive in Ecuador and leave the Atacama Desert soon.
Seven
Today (12 April), we received word from Don McCall that our second bird, the adult male named Seven, had started to migrate north.
It is important to note at this stage that the two male peregrines we tagged (Seven and Sparrow King) have a different type of transmitter than the females. Both males have standard PTT backpacks that do not have the GPS feature. Hence their locations will be less accurate. Since male peregrines are smaller than the females, Mike McGrady and Keith Bildstein wisely decided to have us put these smaller radios on the two males.
These two PTT units are programmed to send out signals every three days only, explaining why the tracking results will be quite different for the males.
Seven moved north sometime between the morning of 9 April and evening of 11 April. Over that period of time, he migrated 600 miles north up into the heart of the Andes Mountains in Argentina, an area known as the altiplano. He flew to a “salar” (desert salt-pan) located over 10,000 feet in elevation.
What is more remarkable is that when the first backpack PTT satellite transmitters were applied to Peregrine Falcons in 1992 by Skip Ambrose in Alaska and Bill Seegar at Assateague Island, only one adult female made it all the way to South America. She was the first known “deep peregrine”. She migrated all the way to Argentina and spent her “winter” at the exact same salar where Seven went. What are the odds?
Incidentally, if you go north northeast along this salar (it looks like a lake on Google Earth), there are two circle icons that have pictures. The northernmost picture shows just how remarkably beautiful this area is…check it out if you possibly can.
Christian has spent time at this location (Salar de Antofalla). He comments that these high elevation salars generally have a few fresh-water springs. Wherever water occurs, there are large flocks of birds that are drawn to them. They concentrate in high numbers at these sites and are quite vulnerable to peregrine attack. Bird species include Baird's Sandpipers, Black-winged Doves, Sierra Finches and Wilson’s Phalaropes.
So it appears that Seven may follow the crest of the Andes north. Only time will tell. Stay tuned and enjoy.
We are alerting our friends and colleagues in Central America that these birds are en route north. If you have friends there, we invite you to share this adventure with them. You can send them a link to the blog (http://frgroup.frg.org) or to the main tracking page (http://www.frg.org/SC_PEFA.htm) where they can see the latest news, at the top left of the page, or find links to all of the birds we are tracking, further down on the page.
Bud
Because of the “marriage” of two recent technologies, miniaturized GPS satellite transmitters and Internet-based satellite imagery maps, we are discovering details about peregrines that have not been possible before. For the team, it is a privilege to witness this.
This is the first time that such detailed GPS data has been available for arctic peregrines traveling between South and North America.
Arena
Arena was the first tagged falcon to begin migrating north. She departed on 2 April 2007 and her first flight extended just over 300 miles north to Antofagasta. We had not expected such an “energetic” first flight. We figured she would slowly work her way into it and increase her distances each day as she got in shape. But that first flight has been the longest so far. She got off to a good start.
Her route has generally followed the Pacific coastline north. However, as several of you have noticed, she often migrated well inland from the shoreline. We thought she would stay right along the beaches to take advantage of the shorebird and seabird populations for food. But it is likely that the onshore Pacific winds are aiding and influencing her inland flights as they flow across the coastal terrace and up into the Andean foothills.
Christian Gonzalez identified her first stopover point (roost) as Hornitos, a beach known to support large numbers of Sanderlings. He has observed peregrines there before.
Later Arena flew past some northern Chile geo-glyphs etched into the desert sands.
If you have not noticed, Google Earth displays these little blue circle/cross icons. If you click on them, you will see a picture of the area, including some of these glyphs. Some of these shots are remarkable and we strongly suggest that you check them out. It provides an excellent “feel’ for the area. In order to see these features of Google Earth you have to turn on certain layers (this is on the lower left side of the screen) - the image at right shows the layers we think you might want to turn on.Christian comments that he has visited many of these inland areas of Chile and that most are loaded with pigeons, doves and passerines.
Arena passed into Peru along the coast near Tacna, an area that Tom Maechtle and I had trapped back in the 1980’s. We caught 23 peregrines during that trip to Peru and so we know that the peregrine density along this coast is high.
In the Atacama Desert of Peru, most of the human activity and settlements are associated with the major river drainages extending down from the Andes. You can clearly see this via Google Earth. These drainages funnel the melting snow waters which support the local agriculture. Cotton was a major crop when we were there in the past.
As in the Chilean Atacama, these settlements support high numbers of prey species including Rock Pigeons and a variety of doves and passerines. Shorebirds are always present along the beaches.
As Arena varied her route between coast and inland, she passed over the Pan-American Highway several times. It is visible as the main road roughly paralleling the shoreline.
It is becoming clear that this falcon migrates in a series of starts and stops. She may stay at one location for over a day, perhaps feeding, resting and augmenting her fat reserves. Her flight north is not a daily process.
We alerted our peregrine colleague, Oscar Beingolea of Lima, Peru, that Arena was on her way north and he has been providing a lot of comments along the way. For example, those long assemblages of white buildings that many of you are seeing are chicken farms, providing meat to the Lima markets. As Oscar explained to us many years ago, these are always excellent places to see peregrines. The readily available supply of bird food attracts prey species of all types which in turn attracts the falcons.
Just before flying over Lima, Arena apparently slept on a headland along the seacoast at the famous town of Pucusana. This is a major fishing (and tourist) village just south of Lima. I encourage you all to zoom in to see the flotilla of boats in the harbor. Check out the picture icons to have a look at this beautiful town.
Last time I was there with Oscar, a Belgian cetologist that I met had just described a new species of beaked whale that occurred offshore from this area.
As an example of this remarkable Google Earth technology, I’d like to point out something. From the roost site dot at Pucusana (south of Lima), look just south a hundred meters or so and you will see a deep cut extending north into the headland. There are actually two. Follow the right cut east (right) and if you zoom in closely, you can see that it has formed a sea-cave that goes underground and comes out on the other side in a small, foaming bay in town. Very cool!
Anyway, Arena continues her migration north and we expect her to arrive in Ecuador and leave the Atacama Desert soon.
Seven
Today (12 April), we received word from Don McCall that our second bird, the adult male named Seven, had started to migrate north.
It is important to note at this stage that the two male peregrines we tagged (Seven and Sparrow King) have a different type of transmitter than the females. Both males have standard PTT backpacks that do not have the GPS feature. Hence their locations will be less accurate. Since male peregrines are smaller than the females, Mike McGrady and Keith Bildstein wisely decided to have us put these smaller radios on the two males.
These two PTT units are programmed to send out signals every three days only, explaining why the tracking results will be quite different for the males.
Seven moved north sometime between the morning of 9 April and evening of 11 April. Over that period of time, he migrated 600 miles north up into the heart of the Andes Mountains in Argentina, an area known as the altiplano. He flew to a “salar” (desert salt-pan) located over 10,000 feet in elevation.
What is more remarkable is that when the first backpack PTT satellite transmitters were applied to Peregrine Falcons in 1992 by Skip Ambrose in Alaska and Bill Seegar at Assateague Island, only one adult female made it all the way to South America. She was the first known “deep peregrine”. She migrated all the way to Argentina and spent her “winter” at the exact same salar where Seven went. What are the odds?
Incidentally, if you go north northeast along this salar (it looks like a lake on Google Earth), there are two circle icons that have pictures. The northernmost picture shows just how remarkably beautiful this area is…check it out if you possibly can.
Christian has spent time at this location (Salar de Antofalla). He comments that these high elevation salars generally have a few fresh-water springs. Wherever water occurs, there are large flocks of birds that are drawn to them. They concentrate in high numbers at these sites and are quite vulnerable to peregrine attack. Bird species include Baird's Sandpipers, Black-winged Doves, Sierra Finches and Wilson’s Phalaropes.
So it appears that Seven may follow the crest of the Andes north. Only time will tell. Stay tuned and enjoy.
We are alerting our friends and colleagues in Central America that these birds are en route north. If you have friends there, we invite you to share this adventure with them. You can send them a link to the blog (http://frgroup.frg.org) or to the main tracking page (http://www.frg.org/SC_PEFA.htm) where they can see the latest news, at the top left of the page, or find links to all of the birds we are tracking, further down on the page.
Bud
05 April, 2007
"Arena" has started her northward migration
"Arena", the first bird we tagged, has started to migrate.From February 26th, when we attached the transmitter, until April 1st, she remained within an area roughly 50km x 20km near the town of Caldera, Chile, as illustrated in this screen shot taken from our web site. The one line that disappears out of the top of the image is her path northward as she started her migration.
On April 2nd the satellite data showed she has traveled about 480km in the previous 24 hours. She remained in that area one day, then on April 4th she flew roughly 260km further north in 8 hours (this is the latest data point so far). This is about 80km SE of Iquique, Chile.
The Google map on our web site will show you all the points to date.
Interesting places she has been
One interesting observation from the satellite data: she is currently —April 4th—near some rather impressive prehistoric petroglyphs at Pintados. There are some nice photographs of these on the Google Earth community pages.
Also of note: before she migrated, she spent some time on a small island* off the coast at Bahia Copiapo. The transmitter data shows she was on the island on 5 different days between March 5th and March 19th, but only during daylight – presumably this was one of her hunting grounds, with her night roosts being on the mainland.
* if you don't have Google Earth installed you can download it from Google Earth web site
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