SCIENTIFIC NAME:
Egretta tricolor
OTHER NAMES:
Louisiana heron
STATUS:
Breeder. Fairly common to common in all seasons in Gulf Coast region. Rare during spring, summer, and fall inland. MODERATE CONSERVATION CONCERN.
DESCRIPTION:
The tricolored heron is a fairly large wading bird with a wing span of 36 to 38 inches and overall length of 22 to 26 inches. The male and female weigh approximately 14 and 12 ounces, respectively. These birds present no sexual dimorphism. Both sexes look alike other than body weight. Tricoloreds have two different color phases during the breeding and non-breeding seasons. During the breeding season, the tricolored heron has a blue bill with black tip and pink legs, both of which turn yellow during the non-breeding season. Their body has a dark bluish gray color during both breeding and non-breeding seasons. Its belly and underwing covert feathers are a contrasting white. As with most herons, this bird has both long legs and neck. It carries its neck in an s-shaped pattern during flight and while on the ground.
Juvenile tricolored herons have a color pattern similar to adults. However, they have a rufous or reddish brown color to their necks and shoulder area on their wings. Their legs and bill are yellow, the back is bluish gray, and belly is white.
DISTRIBUTION:
Tricolored herons are found in the southern and eastern coastal areas of North America, from Maine to Texas with populations on both eastern and western Mexico and Baja California. Coastal areas of Central America, the West Indies, South America, and Peru around the northern Pacific coast also have populations of the tricolored heron.
HABITAT:
The tricolored heron is found in marshy areas as well as shallow pools that are open and tends to be very territorial and solitary. However, they can be found in mixed colonies during the breeding season or when roosting.
FEEDING HABITS:
Herons preys upon small animals associated with wetland habitats, such as small fish, shrimp, tadpoles, insects, reptiles, and amphibians. While feeding, the tricolored heron can be seen standing in shallow water searching for food. Once prey is spotted, the heron tends to run toward it with wings open. This technique is not the only one used by this heron. It tends to change its stalking tactics in order to capture its favored prey.
LIFE HISTORY AND ECOLOGY:
The tricolored heron breeding season takes place during the first of March, at a period of time when water levels are usually low. This is critical because prey will be concentrated in small pools of water and will allow the adults to acquire food without exerting excessive energy. This conserved energy can be focused on the survival of the offspring. Also, it helps the young birds when they begin to forage on their own because it makes it easier for them to find and capture food.
The tricolored heron is a monogamous breeder. This means that males will mate with only one female and females will mate with only one male. Once a mate is chosen, the male picks a suitable nesting site and nest construction begins. Both the male and female are equally involved in the nest building process. The nest is built of sticks and can be found in trees or on a bed of reeds. Once the nest is built, the female will lay two to seven blue to blue-green eggs. Incubation will last approximately 21 days. Hatching takes place over a period of several days with the first hatchling having a better chance of survival than the second hatchling and so forth. After all of the chicks have hatched, it will take them around 35 days to fledge, or start to fly. Once fledged, the young herons will be on their own.
REFERENCES
Imhof, T. A. 1976. Alabama Birds. U of Alabama Press. Tuscaloosa, Al. 94-95pp
Sibley, D. A. 2003. The Sibley Field Guide to Birds of Eastern North America. Alfred A. Knopf Press. New York, NY. 53pp.
AUTHOR:
Griff Johnson, Wildlife Biologist, Alabama Division of Wildlife and Freshwater Fisheries
