Herons of the night

James Dorsey looks at the odd lifestyle of the night heron. From the Spring 2010 issue of Coast&Kayak Magazine. Read the entire magazine online.

by James Dorsey

If you put in for an early morning paddle, while the first ripples of light streak the morning sky, you may see them heading home.

The night herons, as their name implies, have spent the dark hours hunting, and now they descend upon the marina, nesting in the date palms and covering boats like so many watchmen – silent sentinels who will sit immobile until the next sunset.

Nycticorax nycticorax, more commonly known as the night heron, takes its scientific name from the Greek for ‘night raven,’ a reference to its nocturnal hunting habits and also for the croaking call of the black crowned night heron, the best known of the three night heron species.

This bird ranges across North America and south along coastal Mexico, and can be found in specific locations in Central America and the Caribbean. They are numerous along the Southern California coast but can be found in a variety of wetlands including rivers and swamps. They are often in close proximity to their larger cousin, the great blue heron.

I usually pass long lines of them, sitting with their full bellies, watching me with large curious eyes as I glide past on my way to paddle open waters. But I keep my distance. Young herons tend to projectile vomit or deliberately target an intruder for defecation when startled. Young ’uns can be very aggressive towards a paddler when they think you have invaded their space, so a hat is a must!

Adults are gorgeous with a stout neck and build and short legs, standing about two feet tall. Their torso is mostly white or a light gray with a black or dark gray back, but it is their eyes that set them apart. The eye is large and round with a permanent mascara encircling it. It ranges from dark orange to deep red with a jet black iris in the center. It is the massive tally of rods and cones that give their eye this color and allows them to be, along with the owl, the perfect night predator, allowing them to see much like the military does with night vision goggles.

Juveniles are mostly a mottled gray to brown color and reach their mature plumage after about three years.

The dramatic black and white adult coloring combined with a big red eye and bright yellow legs makes this seabird a worthy candidate for a photographer.

Mating begins with the male walking around with head lowered, snapping his mandible to make loud clicking sounds. He might even dress up the act by carrying a stick around to show off his muscles. This is followed by bobbing his head up and down and simultaneously making a snap and hiss sound to attract females. The male night heron is so macho he will reject the first few ladies who show any interest, gradually and begrudgingly allowing one to enter his space once he knows he is the center of attention.

The new blissful couple will bill, coo and preen each other while their legs turn pink in color. Mating usually begins a day after this ceremony in or near the nest.

Night herons tend to nest colonially and the male will begin by claiming an old unused nest or building a platform of twigs that is lined with grass and roots. Sometimes this will be in a tree, but if it is an area light on predators they will just as readily settle for a ground nest. He will then collect twigs to present to the female who now takes over the design of the dream home by intertwining the branches into a snug shelter, while hubby continues to bring her building materials.

When the newlyweds are settled in and four to five days have passed since bonding, a single egg will be laid, with siblings following in two day intervals until three to five eggs fill the nest. After a four week incubation served by both parents, the new hatchlings will tentatively begin to leave the nest at about two weeks old, and by week six will be falling out of tree tops, while frantically flapping their young wings in abortive crash landings. By eight weeks, they are hunting on their own. Curiously, night herons do not seem to recognize their own prodigy and will care for any hatchlings that enter their nest or they may find in an unoccupied one.

Their main diet is fish, but being opportunistic feeders they will also dine on worms, insects, leeches, small eels and any other creepy crawlies that come their way. Even though they have a sharpened bill, like their much larger cousins, the great blue, the night heron catches prey in its beak rather than spearing it and they employ a technique in which they stick their bill into the water and vibrate it rapidly. Some biologists believe this attracts small fish, but that is only a theory. Also, like their larger cousins, they will shuffle their feet through shallow waters to stir up the bottom and reveal any possible meal hiding there.

I could find no accurate populations studies to tell how the species is doing in their fight against a polluted earth, but can only rely on personal observation over the years in my own area that tells me their numbers seem to be increasing, if only slightly.

My most memorable encounter with this creature happened about five years ago no more than 100 yards off shore, just past the breaker line. I was paddling out into a big rolling sea when a young night heron crash landed on my deck, got his feet caught under my bungee and took a header over the side while getting more and more entangled with my deck gear.

I did not want to touch it so I watched while it flopped about for a minute before extricating his foot then righted himself and just sat there, huffing and puffing, while glaring at me, obviously displeased that the log he had chosen to crash on happened to be occupied. I could only guess that junior had gotten disoriented and ventured out to sea, which these birds never do on purpose, and needed a breather before the final push for shore, and I happened to be the only landing pad around.

Once he caught his breath he took a mighty poop all over my deck and flew off.

I will always remember that as a great paddling day.

James Dorsey’s website is www.jamesdorsey.com

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