Fish Wrangling

I have to admit that I don’t usually go out of my way to photograph Great Blue Herons. When I’m out walking with my camera and telephoto lens I’m often approached by people with asking me if I’m photographing either Bald Eagles or Great Blue Herons (or in their words -“cranes”) when I’m focusing on something a little more interesting or harder to photograph. Today I made an exception as I saw one doing something a little unusual and I just happened to be in the right place at the right time.

My 2 year old daughter and I were on one of the viewing platforms at the Courtenay Airpark Lagoon looking at Green-winged Teal when a Great Blue Heron (Ardea herodias) soared into view …

Great Blue Heron (Ardea herodias) Landing
A Great Blue Heron (Ardea herodias) coming in for a graceful landing.

… and landed directly in front of us. We had a perfect view of the bird as it posed for a couple of minutes at the most.

Great Blue Heron (Ardea herodias)
A beautiful Great Blue Heron (Ardea herodias), momentarily at rest.

But as quickly as it arrived, it launched into the air and flew 15 meters down the shore landed, and then took off again.

Great Blue Heron (Ardea herodias) in Flight
The Great Blue Heron (Ardea herodias) flew further down the shore and landed a short distance away.

I was trying to figure out exactly what it was doing and why. Great Blue Herons are the largest of the herons in North America and there didn’t seem to be any kind of predator (like a Bald Eagle or a dog) flushing it.

It was on its way back past the viewing platform that I realized what was going on.

A small flock of Common Mergansers (Mergus merganser) were cruising up and down the shoreline with their heads submerged and looking for fish.

Female Common Merganser (Mergus merganser)
A female Common Merganser (Mergus merganser), one of several in a flock that was fishing in the lagoon.
Male Common Merganser (Mergus merganser)
Male Common Mergansers (Mergus merganser) were part of the small mixed flock that the heron was following.

The heron was following the mergansers, touching down, and looking for any fish that were spooked by the flotilla. In essence the Common Mergansers were acting as fish wranglers and the Great Blue Heron was taking advantage of their ability to herd the fish! I’ve seen mixed feeding flocks of song birds but never anything like this..

The Airpark Lagoon in Courtenay on Vancouver Island is an excellent place to do some leisurely bird watching (and heron photography if you’re so inclined). The short loop around the lagoon is always interesting and there is usually a good mix of both water birds and song birds along the way. Check it out the next time you’re in Courtenay!

Do some more birdwatching and head on over to this week’s edition of I and the Bird hosted by the Twin Cities Naturalist.

I and the Bird