And the stork, the heron after her kind, and the lapwing, and the bat. (Leviticus 11:19)
Herons belong to the Family of Herons, Bitterns and Egrets called Ardeidae. There are 72 different types of Bitterns and Egrets, but most the species are the Herons. When the Bible says “after her kind” they are referring to that whole family of birds.
The herons are long-legged freshwater and coastal birds in the family Ardeidae, (some are called “egrets” or “bitterns” instead of “heron”). Within Ardeidae, all members of the genera Botaurus and Ixobrychus are referred to as “bitterns”, and Zigzag Heron or Zigzag Bittern. However, egrets are not a separate group from the herons, and tend to be named differently because they are mainly white and/or have decorative plumes. Although egrets have the same build as the larger herons, they tend to be smaller.
Although herons look like birds in some other families, such as the storks, ibises, spoonbills and cranes, they differ from these in flying with their necks retracted, not outstretched.
Bill usually straight and sharply pointed; lores naked; head feathered; tarsus with transverse scales; middle toe-nail pectinate or with a comblike edge. (From Color Key to North American Birds, by Frank M. Chapman)
The herons are medium to large sized birds with long legs and necks. The smallest species is usually considered the Little Bittern, which can measure under 12 in (30 cm) in length, although all the species in the Ixobrychus genus are small and many broadly overlap in size. The largest species of heron is the Goliath Heron, which stand up to 60 in (152 cm) tall. The necks are able to kink in an s-shape, due to the modified shape of the sixth vertebrae. The neck is able to retract and extend, and is retracted during flight, unlike most other long-necked birds. The neck is longer in the day herons than the night herons and bitterns. The legs are long and strong and in almost every species are unfeathered. In flight the legs and feet are held backward. The feet of herons have long thin toes, with three forward pointing ones and one going backward.
The bill is generally long and harpoon like. It can vary from extremely fine, as in the Agami Heron, to thick as in the Grey Heron. The most atypical bill is owned by the Boat-billed Heron, which has a broad thick bill. The bill, as well as other bare parts of the body, is usually yellow, black or brown coloured, although this colour can vary during the breeding season. The wings are broad and long, with 10-11 primaries primaries feathers (the Boat-billed Heron has only nine), 15-20 secondaries and 12 rectrices (10 in the bitterns). The feathers of the herons are soft and the plumage is usually blue, black, brown, grey or white, and can often be strikingly complex.
the stork, the heron of any kind; the hoopoe and the bat. (Deuteronomy 14:18 ESV)
The Herons listed in Leviticus 11 and Deuteronomy 14 were on a list of birds that were not to be eaten.