Bayou-Diversity (30 December 2018) At the very mouth of the Mississippi River there is a small island that once served as the headquarters of Delta National Wildlife Refuge. A surplus fire tower was erected on the site in order that the wardens might watch for poachers in the vast flounder-flat marshes of the delta. A friend who worked there once told me that for several years the tower was deemed unsafe and off-limits for a couple of months each winter. It wasn't because of high winds or lightning storms that the 100' tower was condemned but rather the presence of birds that some people called Tiger Owls. This backwoods moniker was attached to great horned owls by people knowledgeable of their innate fierceness. Great horned owls are found across most of North and Central America and a large part of South America. Indeed in many areas they are the apex predators of the skies.
Great horned owls are found throughout Louisiana but are not as common as the smaller barred owls and diminutive screech owls. They can stand almost two feet tall with a wingspan greater than four feet. Mottled and striped in brown streaks with large yellow eyes, they are named for two prominent ear tufts. Their calls are low, haunting hoots that mean business when they are defending territory.
Great horned owls use keen senses of sight and hearing to hunt their prey – almost always at night. Formidable talons coupled with modified flight feathers for silent approach make them stealth predators of darkness. Their list of prey includes rabbits, squirrels, skunks, armadillos, reptiles, other birds, and even young foxes and coyotes. In many places they were once considered outlaw birds because of their habit of occasionally killing poultry. The fact that they also consumed untold numbers of destructive rodents was not considered. Old Louisiana hunting regulations stated that they "may be killed at any time." Now they are rigidly protected by Federal and State laws.
Adults generally have no natural predators, and most mortality is now human-related. Owls are killed by collisions with cars, buildings, and power lines. Less frequently they are still poisoned, trapped and shot.
In Louisiana, nesting begins in December or January, among the earliest of all birds. They do not build nests per se but rather use abandoned hawk, crow, or squirrel nests to lay their two or three eggs. When suitable nests of other species are not available to confiscate they will use large tree cavities or, as in this case, a fire tower in the marsh. At this critical time in their life cycle they are most fierce and will defend their nest "like tigers" even from well-intentioned game wardens. (Adapted from “Bayou-Diversity 2: Nature & People in the Louisiana Bayou Country,” LSU Press)