Wood Storks at Baytown Nature Center

October 1, 2022 ~ The Baytown Nature Center is a 450-acre peninsula along the eastern shore of the Houston Ship Channel where over 315 different species of birds have been observed. It has long stretches of hardwood trees, coastal prairie, natural coastlines, and lots of tiny fresh or brackish water lakes, bays and inlets where birds can shelter and feed. And it has a sobering history of destruction, and recovery.

Baytown Nature Center, east of Houston, Texas, from Google Maps

The nature center is established on land reclaimed from what was an elegant 1930’s subdivision called Brownwood, full of executive homes, swimming pools, pink tile bathrooms. Between 1943 and 1973 so much oil and water had been pumped from shallow wells by the booming cities and industry along the Gulf Coast that hundreds of square miles of land subsided, anywhere from 6 inches to over 9 feet. There’s more on the story from the Lone Star Groundwater Conservation district  here, and at Linda Murdock’s blog, here.

Baytown Nature Center at site of ghost Brownwood subdivision, from Google Maps

After repeated flooding, Brownwood was finally condemned, the dilapidated buildings removed, tough Texas weeds breaking through the once-paved streets, and hardy native vegetation taking over the lawns and gardens. In 1995 the Baytown Nature Center was established where the subdivision once stood, the remnants of neighborhood streets now providing broad walkways into the woods and marshes.

Juvenile Wood Stork, hiding among the White Ibis and Snowy Ibis
1/2500 sec. f/5.6 ISO 500
Nikon D850 with Nikkor 500mm f/5.6E PF ED VR
(Click on any image to enlarge in a new window; close that window to return here.)

On this day, I was introduced to another bird new to me, hiding in plain sight in the flock of white ibis, herons and egrets fishing in an inlet. I almost drove right past this little group of a dozen white birds, thinking Nothing new to see here.

Statuesque Wood Stork beside diminutive Snowy Egret
1/2500 sec. f/5.6 ISO 500
Nikon D850 with Nikkor 500mm f/5.6E PF ED VR

Whoa, baby. That giant is a Wood Stork, Mycteria americana. His fluffy head and neck are a dead give-away: this is a juvenile. He absolutely dwarfs the Snowy Egret in the foreground. He stands about 3 feet tall, and doesn’t have a long neck to stretch up like the Snowy, who is approximately 14 inches tall at the shoulder.

Juvenile Wood Stork hunting in the fresh-water inlet
1/1250 sec. f/9 ISO 1250
Nikon D850 with Nikkor 500mm f/5.6E PF ED VR

A juvenile’s bill is also still a bit orange-colored, not having fully seasoned to the mature drift-wood-gray of adulthood. He was calm and deliberate as he waded among the bobbing White Ibis and scrappy Snowy Egrets which are always in motion. You can see him again in the banner photo above as he paused at the mouth of the inlet, regarding me quietly.

Juvenile Wood Stork flying through flock of other white water birds
1/2500 sec. f/5.6 ISO 500
Nikon D850 with Nikkor 500mm f/5.6E PF ED VR

Then he took off, barely clearing the surface, his powerful wings stroking the air while the smaller white birds whirled around him. An adult has a wingspan of 60 – 68 inches. He passed low-and-slow across a small bay, then perched in a naked skeleton tree. I quickly drove around the little bay searching for a vantage point where I might get a shot, but he was over 500 feet away; good for watching, but not for photography.

Comparing size and markings of black-and-white birds, courtesy of the ICF

White with black trim is a fairly common plumage pattern on large birds. This graphic from the ICF (International Crane Foundation) shows useful comparisons of size, shape, and placement of black accents, between the Wood Stork and other large water birds of North America.

Ken Kaufman, of Audubon.org, explains that white feathers contain no pigment, while black feathers contain melanin. The melanin makes black feathers stronger and more wear-resistant than white, but also heavier than white, which is why so many light-colored or white birds have dark or black wing-tips or, like the Wood Stork, a full set of black primaries.

Wood Stork range map, courtesy of All About Birds

The Wood Stork is the only native stork in North America. Those we see here along the upper Texas Gulf Coast migrate south only far enough to avoid our chilly winters and occasional frosts (not all the way to Argentina), southward along the Central American coast to join the year-round populations in Central America or northern South America for their breeding season. They typically leave Texas in October, so I was lucky to spot them. They roost in colonies of roughly 500 to 5000 birds in isolated groves of tall strong trees rising out of shallow standing water, and feed in fresh water 4-6 inches deep.

Immature Wood Storks in late afternoon shadows
1/1250 sec. f/9 ISO 1250
Nikon D850 with Nikkor 500mm f/5.6E PF ED VR

Late in the afternoon, I retraced my steps to check on the inlet again. There were MOAR storks! The light was poor, the blazing sun sinking towards the horizon almost directly behind the birds, but I persevered. There were now two adults and four juvenile storks in the little group. These two juveniles strode in lock-step past the ever-present egrets. All those black flight feathers and tail feathers are hidden below a cascade of upper-wing white feathers when their wings are folded.

Pair of adult Wood Storks behind tall marsh grass in late afternoon
1/2500 sec. f/5.6 ISO 640
Nikon D850 with Nikkor 500mm f/5.6E PF ED VR

The adult males are roughly 20 percent larger than the females, but otherwise look the same. The adults have a rough bare head and neck. The juveniles lose all the feathers on their head and neck by their third year, and typically start breeding in their 4th year. Wood Storks are monogamous during a single mating season, but then go their own ways, pairing with different birds in the next breeding season. Given the way these two stayed close together, and appeared to be shepherding at least two of the juveniles, I suspect this is a mated pair, and will probably remain together until their migration to their breeding grounds.

Adult Wood Stork (facing right) and juvenile (facing left)
1/1250 sec. f/9 ISO 1250
Nikon D850 with Nikkor 500mm f/5.6E PF ED VR

I don’t know whether the young birds I saw were first or second-year birds, or whether all of the juveniles were related to the adults. Clutches typically have from one to five eggs, but to fledge four chicks would be a major accomplishment.

 Similar to the behavior I’ve observed in Sandhill Cranes, the storks kept lining up in synchronized arrangements, either all facing the same way, or all facing in exactly opposite directions. This is probably a useful survival technique, putting multiple eyes on as much of their surroundings as possible.

Adult Wood Stork’s bill snaps shut in reflexive action
1/2500 sec. f/9 ISO 1250
Nikon D850 with Nikkor 500mm f/5.6E PF ED VR

The Wood Storks feed using tactolocation, a groping behavior. They swish their partially open bill from side to side through shallow water. When they contact prey, their bill reflexively snaps shut and they swallow their prey whole. This is the fastest known reflexive action among vertebrates.

Fuzzy-headed juvenile Wood Storks
1/2500 sec. f/9 ISO 1250
Nikon D850 with Nikkor 500mm f/5.6E PF ED VR

Though highly populous in South America, the Wood Stork was placed on the Federal Endangered Species list by the US Government in 1984 due to habitat loss in the Florida Everglades (early flood management was focused on keeping the water level constant, rather than letting the marsh get inundated, then dry) and a resulting 90% decline in bird population there. Through years of successful conservation and recovery, the Wood Stork’s status in the US was upgraded from Endangered to merely Threatened in 2014. Efforts continue to balance the wet/dry cycle needed by the storks with the water and land management needs of growing human populations.

The Florida Fish and Wildlife Conservation Commission has this to say about their hunting grounds:

“Locating prey using tactile location allows storks to forage in muddy water but requires a relatively high prey density to be effective. Thus, storks tend to forage in wetlands that have long annual wet periods followed by drying conditions to concentrate prey during the spring and early summer months for successful breeding seasons.”

And, I guess this is one of those glass-half-full situations: our ongoing Texas rain shortage throughout the watersheds of the San Jacinto River Basin is shrinking fresh water lakes and bays, including the little inlet where I found the Wood Storks. The shrinkage concentrates the fish, amphibians and other water invertebrates, providing a bounty for the storks. Eat well, guys, and stay safe.