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This Semipalmated Sandpiper chick is from a different nest, but serves as a reminder of how fragile these birds are at the beginning. Only a couple months after looking like this, AHU's chicks will embark on a journey of their own, potentially even exceeding the 25,000km round-trip annual migration of their mother.

This Semipalmated Sandpiper chick is from a different nest, but serves as a reminder of how fragile these birds are at the beginning. Only a couple months after looking like this, AHU’s chicks will embark on a journey of their own, potentially even exceeding the 25,000 km round-trip annual migration of their mother.

 

Every now and then, something happens that is so unlikely that you are left wondering at how small our big world is. Last year, this happened up here while we were out doing routine nest checks and came across a Semipalmated Sandpiper sporting a blue flag as opposed to the normal green. It was a Brazilian banded bird with the code KKL that was one of 1,250 banded that year by New Jersey Audubon in Brazil. With a worldwide population estimate of 2.25 million, that makes the chances of seeing one of those around 1 in 1,800. Up here we only see 100-200 Semipalmated Sandpipers a year. The odds are definitely stacked against us, but apparently not too severely to stop us from seeing one.

KKL, our first Brazilian bird (photographed 2012) on his territory. He never appeared to find a mate, and did not return in 2013 that we could determine. Hopefully wherever he is he is having better breeding success.

KKL, our first Brazilian bird (photographed 2012) on his territory. He never appeared to find a mate, and did not return in 2013 that we could determine. Hopefully wherever he is he is having better breeding success.

 

Sadly, this year our blue-flagged friend did not come back, despite intensive searching of the territory from last year and every researcher checking each bird we came across just in case. It turns out that we didn’t need KKL this year, however, because we had an even more amazing stroke of luck. After checking on nests and searching for new ones on July 4th, I got back to our data tent and found that Scott was already back after doing his work. I asked how his day was, and it seemed pretty standard until he casually dropped the bomb, “Oh, and I discovered a Brazilian banded bird on a nest we had already found… and it’s not KKL.” My mind totally blown, I immediately raced out and got some photos of the bird, confirming the letters on the flag as the same ones that Scott had earlier read: AHU – our exceedingly unlikely new guest.

Our celebrity in all her glory, defying the odds! Very satisfying to have a Brazilian bird with a nest this year after the sad fate of KKL's breeding attempt in 2012.

Our celebrity in all her glory, defying the odds! Very satisfying to have a Brazilian bird with a nest this year after the sad fate of KKL’s breeding attempt in 2012.

 

Assuming that this bird was banded by the same person who captured KKL, a shorebird researcher by the name of David Mizrahi, I sent an email off to him with a photo of the bird and received a prompt response including all that we know about AHU. She was initially banded on Jan 22, 2012, as a bird that hatched in 2011 or earlier, making her at least three years old this year. Based on the length of AHU’s bill (19.2mm) and the fact that she is part of the breeding population here at the Canning River, we can definitively tell that she is a female since her bill is longer than 17.5mm. Both KKL and AHU travel about 12,500km one way each spring and fall from Maranhão state, Brazil (1°26’50.44″S, 45° 9’17.40″W) to the Arctic and back.

 

AHU’s nest currently has three eggs in it, two of which are showing signs of hatching – small cracks spiderwebbing out from a central location as the chick inside begins to chip its way out of the eggshell. In less than a day, the chicks should break through and carefully remove the tops of the eggs, crawling out into the nest cup. Within several hours, they will be able to walk and will likely be out and about with AHU and her mate in short order.

AHU's nest only contains three eggs, an unusual occurrence as compared to the standard four. Two of them are primed to hatch, and will likely do so in the next 24 hours.

AHU’s nest only contains three eggs, an unusual occurrence as compared to the standard four. Two of them are primed to hatch, and will likely do so in the next 24 hours.

 

So what are the chances of having two of the 1,250 banded birds from January 2012 occur at the same exact study area in northern Alaska? Apparently pretty good. It raises a lot of questions though, some of which we could have answers to in a little over a year. Having only one banded bird here was just an amazing fluke, but having two suggests that many of our Semipalmated Sandpipers here at the Canning, or at least some, go to northeastern Brazil for the winter. According to David Mizrahi, close to 100 of his banded birds have been resighted, some on migration in the central Unites States, and some on the breeding grounds like the two here. Interestingly enough, the 300-400 Semipalmated Sandpipers that we have banded here over the past four years have never been seen elsewhere by anyone.

 

This season we are putting out technology that should hopefully give us more than just two data points to piece together this puzzle. This year, we placed 29 geolocators on Semipalmated Sandpipers. The geolocators are small leg-mounted dataloggers that have an accurate clock in them and record light levels. When you know what time it is when the sun rises and sets and the length of the days and nights, you can determine a rough latitude and longitude. Unfortunately, you have to recapture the bird and remove the geolocator to get the data that it has collected. So we put these instruments on, wait for the following breeding season and hopefully find the nests of the same birds here next year! Many other breeding season research camps like this one are putting geolocators on Semipalmated Sandpipers this season as well. With all of the data combined, hopefully next year we should be able to learn more about where different parts of the overall Semipalmated Sandpiper population go at different parts of the year.

This is one of the geolocators, shown here next to the tip of a mechanical pencil for size. These sit on the upper leg of the bird, in the same location as the flags above on KKL and AHU. The side shown here is the light sensor, and faces outwards to collect data for a year after deployment.

This is one of the geolocators, shown here next to the tip of a mechanical pencil for size. These sit on the upper leg of the bird, in the same location as the flags above on KKL and AHU. The side shown here is the light sensor, and faces outwards to collect data for a year after deployment.

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