New Female at Burlington Lift Bridge

May 24, 2016 - Burlington - Lift Bridge

Tracy Simpson Reports:

At first it was only a suspicion follewed by a report of something different at the bridge this year and so Bruce and I decided to take a trip down to try and confirm adult identities.

Normally the Lift Bridge is one of the earliest (if not the first) nest site in southern Ontario to hatch young, either hatching just before MEC or right in step with that site   This year the clutch size of 5 eggs coupled with the continued incubation at this late stage (at least late for the bridge) raised a few eyebrows.  We started making plans to check in on Cirrus and McKenzie as this was not the norm for them. A few days ago I received a report from local watchers that we’re seeing a female banded black over red, not black over green as Cirrus is.  Yesterday Bruce and I set out to try and get some answers.

When we arrived at the bridge we found McKenzie on the Hamilton tower of the bridge lounging in the shade while keeping an eye on the box.  Several lifts occurred while we were watching him but he didn’t make a move nor hunt.  It was two hours before he took off of that ledge and at no time did he take food to the box.  We are pretty confident that we have no hatch as of yet.

At around 4pm I was looking up at the nest box when out like a bullet came the female.  She flew straight towards the Hamilton tower and then did a full 90 degree drop and dive at something just out of our sight.  McKenzie joined her at this and when the two pulled out of their drop, he flew straight to the nest box and disappeared while she flew up to the Hamilton hydro tower.  We turned our scopes on her but she didn’t stay long.  It was long enough however to confirm that she is banded black over red on her left leg with a silver USFW band on her right; this was not Cirrus.  We did get a partial read of the band but all we can conclude with certainty is that this is a new female.

She left the tower and flew over to the harbour side of the Burlington Skyway where we lost sight of her for over an hour.  She was definitely on a hunt.  The next time we saw her she was bombing up the canal and had lined up a cormorant.  In an incredible show of pure nastiness, she drove the cormorant head first straight into the canal waters, skimming the surface as she banked up.  Focused, determined, fearless and on fire is how I would describe her entire time in our view.  She flew off and landed in the tower again looking for more things to line up and dispatch.  It wasn’t long before she was once again out of our view.  In all of the looks we did get of her, she appeared to be in full adult plumage with strong barring throughout her bib and chest.  If she would have sat still long enough we could have had more of a view but she was clearly on a mission.

This years nesting season has certainly been one of great change.  The Burlington Lift Bridge is now the fourth confirmed site with an adult changeover as young up and coming birds fight for the rights to an established nest site.  We are unsure when this change took place or where Cirrus is now.  We can only hope that she is safe.  We will continue to work on a full identification of this new female as we await their first hatch.