Wednesday, March 25, 2015

Where have all the heron gone?

by Nick Kotula, JRA Guest Contributor

Every year the swallows return to Capistrano.  Every winter the monarch butterfly returns to Mexico.  When a new iPhone comes out all of our old iPhones don’t work as well as they used to.  And at the beginning of spring the herons return to their nesting spot by Pipeline Rapids in Richmond, Virginia on the James River.  This is just how the world works.  Or so I thought.

You may or may not remember my reporting on the heronry (herons + rookery = heronry) in 2012 and again in 2013.  I’m not the only one who expected the return of these fantastic birds.  The City of Richmond has flags proclaiming the “Heron Rookery” and the James River Park System has signage explaining their mating and nesting habits at Pipeline Rapids.  Perhaps we were all naïve, because this year the herons did not return.

An active heronry in early February 2012.

Nothing but empty nests in late March of 2015.
I first went to check on the heronry in early February.  It was cold, and it had been even colder so I wrote off the lack of feathered friends as a wintry fluke.  Wouldn’t you have liked to stay south this winter?  Come the beginning of March, I began to have my doubts.  This week I went to check up one more time, and only found one solitary heron.

One is the loneliest number that you'll ever do.
When not in mating mode, the heron is a solitary and territorial creature.  After an hour spent on the rocks and the pipe at the rapids, I had to conclude that this was this singular heron’s territory, and there would be no nesting here this year.  The Richmond-Times Dispatch had written a piece earlier in the month about this, but I wanted proof and I refused to give up hope.  But a heronry is not a fast endeavor.  Courting is a complex process, even for herons.  Much like humans the heron males has to display his manly feathers, dance the man dance of his people, and lock bills with his intended.  The males then spend weeks collecting the stickiest sticks that they can find, building the perfect nest they can and then watching as their intended completely shows them how everything they did was wrong and does it themselves.  And don’t even get me started on the mating!

The point is this all takes time.  If it hasn’t happened yet, it’s not likely to happen.  Much like the Purple Martins (whose murmurations inspired a festival at the 17th Street Market in Richmond), the herons have found somewhere else to nest in 2015, and we may never really know why.

He's certainly not telling.
So what does this mean?  Well, on a positive note:  A heron with little heron mouths to feed typically consume about 4 times their body weight in fish per day.  Despite their large size, your typical heron only weighs about 5-6 lbs due to their hollow bones.  So that’s about 20 lbs of fish per day.  Adult shad weight between 3 to 8 lbs, for our purposes we’ll average this out at 6lbs.  That means every heron that is not here means an extra 3 (and some change) shad per day.  (The shad run through Pipeline was thought to be one of the primary reasons for the heronry, but they are known to eat other fish and also amphibians and even rodents!)  Multiply that 3 fish by the 100 or so herons that were usually there and you end up with a lot less competition for a lot more fish for those humans who enjoy that kind of thing.  (This all assumes that the herons are not nesting further downstream and catching them before they ever make their way to Pipeline.)  If the run is good again this year, fishermen should take delight.

And a good year for osprey!
Personally though, it just makes me sad.  The return of the herons was like seeing good friends who abandoned you for warmer climes during an absolutely miserable winter.  They were a sign of spring more potent to me than daffodils or tax forms.  While I’m glad to see one hunter holding down the fort (so to speak) I really hope next year sees a return of my winged brethren, otherwise those flags are going to look pretty daft.