Just a few weeks ago, as I traveled from Marco Island to South Naples, there were very few birds to be seen in the canals along Collier Boulevard. Right around December 5th, I began to notice a Wood Stork or two.
A few days later, several more were noticed by yours truly, and a thought crossed my mind that maybe this will be a successful breeding season for these long-legged fishermen. Only time will tell over the next few months.
There only about 8,000 nesting pairs in the wild, down from a breeding population of nearly 20,000 pairs in the 1930s. Why the decline? Primarily it is loss of habitat and weather conditions. Nesting primarily occurred in the Everglades and the draining of the wetlands by the construction of levees, floodgates, canals, etc., altered the water flow in their feeding grounds which altered the amount of food available.
Wood Storks have a unique feeding technique that requires more prey in a smaller area than some other birds may need. After periods of heavy rain and/or flooding, the fish population will increase. As water levels recede when times become drier, a higher density of food is now available for the storks in a concentrated area.
They feed on small fish, about 1 to 6 inches in length, and capture their prey by a process known as “tacto-location” or “grope feeding.” Because of their long legs, they will enter an area of water about 5 to 10 inches deep. With their bill partially open they will probe, or sweep, an area back and forth until the bill touches a fish. It will then snap the mouth shut at an extreme rate of speed.
How fast? The response time of this natural reflex is 25 milliseconds, which makes it one of the fastest reflexes of any vertebrate on the planet! Capturing fish in this manner requires ideal conditions of, again, proper water depth and a concentration of fish in that area. If these conditions cannot be met, then enough food may not be available to sustain throughout a breeding season.
It is estimated that a nesting pair, feeding two chicks, needs about 430 pounds of fish for the breeding season. Therefore, conditions must be ideal from the start of the mating season until the end to assure the survival of the entire family. Last year, in Corkscrew Swamp Sanctuary, there was too much rain early in the season, making feeding areas too deep for the storks to catch fish. Although they will sometimes travel as far as 80 miles from their breeding grounds to obtain food, these wet conditions resulted in a poor mating season in Lee County.
On a brighter note, there were about 2 dozen Wood Storks at the Marsh Trail in Collier County on Wednesday, December 11th. The Marsh Trail is on U.S. 41, 3 miles south of San Marco Road. Adding these to the storks seen on the roadsides of Collier Boulevard, it’s been a good start for sightings this Fall.
Wood Storks in this area typically lay eggs as early as October, with the young taking flight in February or March. If the adult is riding thermal currents to feeding areas at this time, they probably won’t arrive at these areas until later in the day, since thermal currents don’t form well in the morning. Feeding opportunities could, again, be difficult or limited.
The storks themselves are quite large. They can grow to be 45 inches tall and sport a wingspan in excess of 60 inches. The plumage is white except for black outlines at the edge of the wings and a short black tail. There are no feathers on the head or near the black bill, earning them the nickname “Ironhead.” They have also been called the “Preacher Bird” because of the stance they take when resting, seemingly very solemn and still. Without facial feathering, the bird does have a face that only a mother could love.
Let’s hope that conditions are a proper mix of not too much water in the feeding areas and plenty of fish close to the nests. Being “Colonial” nesters, there are many birds in a small area vying for food. Alteration of waterways resulting in habitat loss is difficult enough for the indicator species. Mother Nature needs to be nice and give them the best chance possible for a great breeding season.
Bob is a Naturalist on the dolphin survey vessel Dolphin Explorer departing from Rose Marina, Marco Island. He is the author of 2 books, available locally, and a speaker at several venues throughout south Florida. Bob loves his wife very much!