A tale of eyes nearly bigger than a stomach
I try to get in some nature when and where I can. A recent errand run below found me at a favorite wetland “go-to”, the Walden and Sawhill Ponds open space trails. I was on my way out when I happened upon this juvenile (as noted by the dappled feather pattern of its neck) great blue heron standing at the edge of the reeds. Not having seen much photo-worthy activity on my walk, I decided to try and capture a few quick portraits in the fading light before calling it a night. What happened next was both impressive and quite comical to observe.
Great blue herons are predatory birds who live exclusively around water. While their diet is generally pescatarian (fish eating), they also hunt all kinds of animals from snakes, reptiles and lizards to rodents and even other small birds. They spend up to 90% of their waking hours patiently waiting for or stalking prey. While this youngster was seemingly providing an idyllic pose in evening light, it was intent on a mission to find some dinner before dark.
As I crouched on the bank of the pond taking photos and trying not to startle the bird and cause it to depart, it turned sharply from its pose and went into an alert state. These birds have stunning eyesight capabilities, considered about 3 times more effectively detailed than humans. Their eyes function like a telephoto lens allowing them to visually “zoom in” on a target and determine distance even through the distortions of water. Dinner was lurking just below the surface, and this bird was on a mission.
This alert state of hunting often has them very slowly wading towards their prey, with head often cocked at an angle to aid them in avoiding light glare on the water’s surface. While their moves are typically cautious and calculated, this bird wasn’t wasting any time (ah, the impatience of youth…). It very quickly (in a relative way) made its way from its initial peaceful perch over to a better position near its quarry. With only a very brief hesitation to calculate its attack, it seized the opportunity and plunged its head in for the kill.
While smaller prey might have herons utilizing a “catching” technique, larger animals require a more brutal approach in the way of using their bills to stab. This allows them to more effectively disable their meal, as wings are no help when it comes to managing and maneuvering a meal for devouring. Without the ability to “peck at” their food like a smaller-billed bird might do, they must swallow their prey whole, and a larger catch should ideally be mostly immobile.
When the heron finally drew its head out of the water from its attacking plunge, I was astounded at its prize. A carp that was larger than the bird’s head was apparently too distracted by its meal of pond vegetation and hadn’t noticed the rapid moves of its hunter. As seen in the image, the stabbing technique was absolutely necessary (the end of the lower bill seen protruding from the fish’s head).
Typically, a meal will be devoured quite rapidly after a catch, but this youngster seemed to display both great pride at its catch, as well as a bit of confusion as to how it should proceed. It spent the first few post-kill minutes strutting about the water as if showing off the prize to whomever might be watching. A few times it dipped the fish back into the water and I chuckled at the thought that maybe the kid was trying to keep it alive so as to be able to show it off longer.
Eventually the heron carried the fresh-water “whale” over to a rocky shoal near the shore and placed it on the rocks. It then proceeded to pace back and forth, coming at the fish from various angles, looking to be quite confused as to how it might undertake eating such a massive catch. Often these birds will pick up and flip around their prey to position it head-first for ease of swallowing. It appeared as though the flipping around part was far too big of an undertaking with the giant catch, and the poor bird just didn’t know how it would make that head-first swallow happen from the ground.
For the next 10 minutes or so the bird struggled to work out its culinary puzzle. A few times the youngster picked the fish up and carried it back into the water, my thought being that it might be easier to gain the head if the fish was floating. These attempts were to no avail, and after carrying the catch back to the shoal I wondered if it might just quit and go find another fish. Not wanting him to give up, I quietly cheered the youth on with its attempts, laughing at the comical drama.
After nearly 20 minutes it finally committed. Sadly, I wasn’t provided with a view of the initial swallow as its back was turned to me in the rapidly fading light. It did turn before the final gulp, displaying a grotesquely engorged and carp-shaped neck. I gave it a hardy huzzah, then clamored my way up to the trail and back to the car with many thanks and giggles at the performance.
The next day I had to return to the same area and, with a little bit more light left than the previous evening, decided to go back with hopes of more action. After enjoying another heron’s successful hunts, I came upon my young friend out in the middle of the same pond where it had been victorious the night before. It didn’t appear to be in any mood to hunt, and I wondered if it had even made any attempts to fly. Herons consume 1-2 pounds of fish per day (20-40% of their own weight), and I imagine the previous evening’s meal was holding it over quite well. Before continuing my walk, I gave it a brief greeting and short prayer for a quick recovery from its inevitable indigestion.
Originally published in The Mountain-Ear
