Green Herons are stocky birds with relatively short, orange legs compared to other herons. Overall
length is 16-18 inches long. Sexes are similarly colored but females are smaller, duller, and lighter. The adults have a greenish black cap and back and dark colored bills. The wings are green and blue cast with gray underparts. One would not describe their vocal range to include song but call rendered as skow, skeow, peu-ah, or skyow.
 |
| Green Heron |
GREEN HERON DISTRIBUTION AND MIGRATION
Green Heron breeding range covers most of central and eastern United States. They winter around the Gulf of Mexico where there is suitable habitat for feeding. Western coastal populations are smaller but they are expanding their breeding and wintering range.
Green Heron migrate north in late winter or early spring usually at night and in flocks. They arrive earlier than other Herons and researchers speculate that this is possible because Green Herons will feed in twilight and this provides a longer feeding time period in the short days of early spring.
 |
| Green Heron |
GREEN HERON HABITAT AND FOOD HABITS. This bird is found foraging in any type of freshwater to marine environment throughout its breeding range. The species is most conspicuous during dusk and dawn, and if anything these birds are nocturnal rather than diurnal, preferring to retreate to sheltered areas in daytime. They feed actively during the day, however, if hungry or provisioning young. Shore-living individuals adapt to the rhythm of the tides. They mainly eat small fish, frogs and aquatic arthropods, but may take any invertebrate or vertebrate prey they can catch, including such animals like leeches and mice. Green Herons are intolerant of other birds - including conspecifics - when feeding and are not seen to forage in groups.
They typically stand still on shore or in shallow water or perch upon branches and await prey. Sometimes they drop food, insects, or other small objects on the water's surface to attract fish, making them one of the few known tool-using species.They prefer densely wooded swamps for nesting. Green Herons will even feed in open water when food is plentiful. Green Heron primarily eat fish but their diet also includes invertebrates depending on availability. Herons hunt by luring prey with a variety of bait and then they use their bill to grab or spear it.
 |
| Green Heron |
GREEN HERON BREEDING. Evidence from studies indicate Green Heron are monogamous but there is a high degree of extra pair mating. More data is needed to determine if they are truly monogamous. Males perform a series of courtship displays and they defend territory aggressively. Green Heron are social intermediates between solitary and colonial nesting herons.
GREEN HERON NESTING. Nests building strategies include new construction, refurbished old nests, or new construction on top of old heron nests. Males select the nest site and initiate construction. After mating, the male gathers nest material for the female who completes the nest. Egg laying dates vary because of the large breeding range but it’s generally later in northern latitudes. The hen will lay 3-5 pale green to bluish eggs and both the male and female incubate for 19-21 days. Both parents feed and brood the chicks.
GREEN HERON STATUS. BBS data reveals that overall populations slightly decreased in the United States but this included increased western populations and decreased eastern populations.14 We observed Green Heron with some breeding evidence at 21% of sample units and this included 11% Possible, 7% Probable, and 3% Confirmed records.
GREEN HERON CONSERVATION. Management has not been a major focus because Green Heron populations overall are stable. Conservation should be addressed to wetland management since these birds depend on them. Green Heron have proven adaptable to constructed or enhanced habitat.4 We observed breeding evidence at restored wetlands and at excavated ponds at the golf course.
