Great Blue Heron & Diet

Ardea herodias, known as the Great Blue Heron, is the largest heron in North America. In the Florida Keys and the Caribbean, there is a white morph of Ardea herodias known as the Great White Heron, which was formerly considered a different species. Likewise, a white-headed morph called the Wurdermann's Heron was once considered a separate species, but now is lumped in with Ardea herodias. These magnificent, long-legged, long-necked wading birds are common to marshes, wetlands, salt ponds, mangroves and sea shores, and their diet consists of smaller creatures normally found in these ecosystems.

  1. Great Blue Heron's Diet

    • The Great Blue Heron and its morphs are opportunistic feeders. They hunt by standing perfectly still in salt or fresh water for long periods of time, grabbing anything that swims within range of a quick thrust of the dagger-like bill. Though the heron's diet is mainly fish and crustaceans, Great Blues may be seen walking slowly through marshes or meadows, scarfing up insects, lizards, small snakes, frogs, mice or even turtles or birds in their path. Herons are rarely seen drinking; generally, they get all the hydration they need through their food.

    Feeding the Great Blue Heron in Captivity

    • In a zoo or long-term rehabilitation setting, Great Blue Herons most easily adapt to eating a variety of live or frozen whole fish from salt or fresh water. Obtain small whole fish such as thread herring, capelin and smelt readily from bait or zoo supply stores; captive herons usually accept these. The Key West Wildlife Center offers its permanently disabled display herons and Great Blue Herons in rehabilitation a variety of frozen fish: 10 to 15 fish twice daily from a shallow bowl or tub of water. The birds take the fish directly from the bowl or tub, imitating their natural hunting technique. This also insures that the birds get enough moisture from the wet fish to keep hydrated. However, a long-term diet of frozen fish may cause thiamine deficiency, which can be remedied with vitamin supplements or non-frozen foods. For example, the Hamilton Zoo in New Zealand offers its large herons a smaller amount of frozen fish along with a "heron mix" of minced horsemeat, trout pellets and chick starter crumble, plus vitamins daily.