For many years, my favourite artist has been Claude Monet, so I never expected that looking at something in nature that evokes thoughts of his brushstrokes could possibly cause me so much frustration.  As the summer progresses here in the Carden Plains in Ontario , the days have gotten hotter and more humid.  Many people are thrilled, but those of us who spend days looking through scopes and binoculars are not among that group.  Looking through my scope at maximum magnification, desperately trying to discern the colour combination of the bands on tiny wild loggerhead shrike legs is already incredibly frustrating (Was that white over silver bands on the left leg? Maybe it was light blue instead of white and the sun’s glare just made it look white… Oh no, it moved and now it looks like that is its right leg… but what are the bands on the left?) In this heat, objects viewed at a distance blur and shimmer in the haze, appearing almost like the strokes of an impressionist artist’s paintbrush.  The first time that thought popped into my head I knew I would never look at a Monet painting the same way again.  I love impressionism in art, but I prefer realism through my scope and bins.

A stainless steel ID band being attached to a juvenile shrike

Things at the ranch have been proceeding at such a break-neck pace that they barely feel real.  Our first six clutches of juvenile eastern loggerhead shrike have been brought to the site from their breeding facilities, acclimatized to their surroundings (enclosures just like those seen in the video by Napanee biologist, Nicole), proven that they are capable hunters of live mice and insects, and been released.  Before release, all shrikes are equipped with one stainless steel ID band with a numeric code that can be tracked if the bird is recaptured, just like a standard bird band (except that most normal bands are aluminum which shrike can easily remove with their powerful beaks).  At this time, measurements are taken including their weight.  The shrike’s weight ensures that each bird has been successfully hunting prey, but it also allows us to determine which additional tracking technique will be applied to that bird.  Birds under a set weight limit are given a unique combination of three colour bands which, in addition to the standard band, allow us to identify each individual shrike.  Birds over that weight limit are given an even more exciting tracking system – a radio-tag harness which emits transmissions to nearby Motus towers every few seconds.

The shrike in front shows off its blue breast stripes. Behind, you can see a radio transmitter dangling just below the second bird’s tail.

These harnesses are incredibly light, but we are very cautious that they are not heavier than 3% of the shrike’s body weight to ensure that there is no impact on the bird.  The recommended limit is 5%, but we are even more cautious, as the well-being of each shrike is always the utmost priority.  We also apply a unique colouring to the feathers of each bird before they are released, as bands are not easily visible and the radio-tagged birds cannot be distinguished without looking at the serial number on their one band, an impossible feat without catching the bird.  This colouration fades within a week or two and allows us to track which juveniles remain onsite during the week or so following release.

We soft release the conservation-bred shrike, which is also called “hacking”.  While the juveniles are in their enclosures, we put a small portion of mealworms on the inside shelf of the release door at every meal which gets them used to coming to this area.  On the morning of release, we put their normal insect diet in large containers outside of the enclosure, open the release door, and put their usual bowl of mealworms on the shelf outside of the enclosure instead of inside.  We then monitor from a distance for at least an hour or when the last bird has exited the enclosure, whichever comes first.  If there are some birds that have not left by the end of an hour, we leave and return two hours later to monitor if any are still in the enclosure, repeated as many times as necessary until all have exited and the door can be closed.

Samantha opening a release door and placing mealworms on the outer shelf to lure out reluctant juveniles

Each clutch of birds has distinct personalities.  Some are loud, or inquisitive, or cautious, or any combination of traits.  The first shrikes we released all exited in under an hour.  These birds had been noisy and constantly watching and interacting with the wild birds in the field.  The second group released were a bit more cautious, staying in the covered portion of their enclosure and very aware of human presence.  On their release day, there were many false starts with birds exiting the enclosure, hopping on top and looking down at their siblings, anxiously trying to find a way back inside their former home.  The world must have seemed very large and intimidating to these birds, but after just over an hour, all but one had exited.  This one showed absolutely no interest in leaving its cozy corner, so we left in hopes that it would exit without us nearby.  There was a short rain shower before Samantha went back to check on them two hours later and she was disappointed to see that not only had that last bird stayed inside, three more shrike had joined it including one from the first release group!  They all left eventually, and the third release group departed at a pace somewhere in between the first and second groups.

Lead Biologist, Hazel Wheeler, installing a Motus tower on a volunteer’s chimney.

After release, we provide food in containers outside of the shrike enclosures, gradually decreasing the frequency to encourage the birds to move offsite and find their own hunting grounds.  Two of the colour-banded juveniles have been seen at nearby sites since their release.  I am eagerly awaiting my first sighting of a radio-tagged release bird, but soon we will have data from the radio towers that they pass, revealing their dispersal across the region and ultimately their migration south.  We are currently housing our fourth and fifth groups of juveniles which will be released shortly to make room for even more shrikes.  All going well, this year may have a record number of juveniles released including several clutches from our partners at the Smithsonian Biodiversity Conservation Institute in Virginia which should be arriving shortly.  Only time and the help of Motus will reveal whether these birds return to Ontario next breeding season or stay further south…  I, for one, can’t wait!

-Alisa Samuelson, LoyaltyOne Young Conservation Leader, 2017.

 

Juvenile shrikes’ first taste of freedom