Wednesday, June 3, 2015

Banding Sanderlings

Two weeks ago now, I had the chance to join Dr. Christy Morrissey, a toxicologists from the University of Saskatchewan (of Songbird SOS fame!) and her grad student, Kristin and assistant Christina at their study site at Chaplin Lake, near Chaplin, SK.  Here the team catches Sanderlings, Red Knots and Semi-palmated Sandpipers. 
A view at dusk of the mist nets along the dyke.

Kristin is studying how heavy industrial pollutants affect how shorebirds are able to build up fat reserves which they need to make their long flights from South America to the Arctic.  Shorebirds across the world are experiencing pretty alarming populations declines and one idea is that they are not able to put on enough fat to 1) make the journey at all or 2) reach the breeding ground in such poor body condition that their reproductive success is significantly impacted.

Banding Sanderlings is not for the faint of heart or I should say not for those who like their sleep... This is because Sanderlings have fantastic eyesight and can see the mist nets that are used to capture them during the day, therefore banding occurs at night!  So out we went at dusk to the dykes on Chaplin Lake where the team had their nets set up.
A Sanderling with white flag, P28, with orange band on lower left leg.  I learned shorebirds can easily get leg cramps, so while handling the birds you try to let the legs dangle instead of holding them against your hand.

Our first night we captured 8 Sanderlings and 1 Semi-palmated Sandpiper.  The second night we caught 18 Sanderling, with 12 being caught between 3 and 4:30 am.  Once out of the net the birds are banded with an aluminum band on their upper left left leg. Then an orange color band goes on their lower left leg.  Lastly, a small plastic flag, goes on the birds upper right leg.  The flag the team uses is white with black coding.
The nano tag, white flag, and orange band to be put on a Sanderling.  You can see a piece of pencil lead right above the white flag.

Because shorebirds can travel so far (Red Knots over winter at the very south tip of South America and breeding in the Arctic!) a great deal of coordination goes on amongst sandpiper banders.  If a bird is banded in Canada and the bander puts on a flag, then that flag must be white.  The significance of the bands' placement can be more complex, as with this project, where birds get an orange color band on the lower left leg as well which means the bird was banded at Chaplin Lake in 2015.  

One of the last things team does before the Sanderling is released is a nano tag is glued to its back and feathers.  This nano tag sends out a radio-signal that can be detected with a traditional receiver.  However, the team has deployed 3 receiver towers around Chaplin Lake, as well as 2 towers at Reed Lake, and 1 at Old Wives Lake.  These receivers have a mile or two sensitivity and automatically detect the nano tags when they are in range.  Using this equipment the team will be able to know exactly how long it is taking the birds to put on their fat reserves to make the final stretch to the high Arctic!  The nano tag only weighs 0.6 grams compared to the 45-90 gram bird (depending on the fat reserve!).  So they are less than 1% of their weight.
A pair of Sanderlings all processed.  You can barely see the nano tag wire coming off the birds back.
What perhaps makes this project even more exciting, is the fact that Christy and her team went down to Texas earlier in May this year and captured Sanderlings and Red Knots that are presumed to come north through Chaplin.  If the tagged birds from Texas arrive at Chaplin Lake, the towers will record the radio frequency from the transmitters and the team will know who has arrived and exactly when and for exactly how long they stay.  I talked with Christy this week and she said so far a few of the birds tagged in Texas had arrived at Chaplin!!

The nano tags only have battery for about 65 days, and will fall off the bird once they moult their back feathers, so they are not designed to stay on for very long.  Once the birds leave Chaplin, there are only 2 more towers north, one along Nelson River and one at James Bay.

However, there are lots of towers in Ontario and along the eastern side of the continent.  Interestingly, Sanderlings flying north in the spring stop at Chaplin to refuel, but during the fall they do not come to Chaplin, instead they swing east and follow the east coast as they make their way to South America (some will stay in North America all winter).  So perhaps if one of the tags decides to really hold out for battery life, they could be detected on their migration south.

Additionally, birders can watch for these little bands on these little birds, along the coast in the fall.  If you can see a white flag (upper right), aluminum (upper left), and orange band (lower left), then you know the bird was banded in Chaplin in 2015.  

If you do see a banded shorebird you can report your sighting to, which is a site that is specifically dedicated to banded shorebirds.  If by chance you find a banded Sanderling and find this post, I would love to hear from you!

I had a blast banding shorebirds and am grateful for the opportunity to tag along with Christy and her team.  
The last Sanderling we banded on Saturday morning. 

 An unusual wear in the tertials of this bird, possibly suggesting a Second Year bird, which would be unusual as SY birds do not breed and typically remain on the wintering grounds.  

The view at dawn after a long night of Sanderling banding!

1 comment:

Christy said...

Thanks Jared for the super post! It was really great you could come help out this year. Hope you can come again!