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Herons, Egrets, and Bitterns 281

should be considered for twice daily, 5% body weight (50 ml/kg), pre‐warmed, sterile, isotonic,
subcutaneous fluid injections, which may be discontinued when the bird is eating well.

Hatchlings

Hatchling birds should be offered small pieces of fish that have been soaked in water or elec-
trolyte solution and sprinkled with powdered calcium. It is very important for the fish to be
sliced diagonally, so that each sliver has two pointed ends. Young birds learn to navigate food
in their mouths by instinctively finding “head” and “tail” ends of food items, and only diago -
nally‐sliced fish slivers can substitute effectively for whole small fish. Hands should be dis -
guised in a sock or puppet of appropriate appearance to discourage habituation to humans.
Herons and egrets are less vulnerable to imprinting than many other species of birds, but they
are capable of it, so it is always best to err on the side of caution. Avoid chicks seeing human
hands associated with food. Birds should be offered food hourly throughout the day until they
begin self‐feeding.
The size of the fish pieces offered should correspond to the size of the hatchling. Small hatch-
lings should be offered small fish slivers, about the size of a 10 g smelt, sliced into four to six pieces.
At the other end of the size spectrum, Great Blue Heron and Great Egret chicks can eat whole 10 g
fish even at the hatchling stage. Snowy Egrets and the Black‐crowned Night‐Herons may be fed 5 g
fish halves at the hatchling stage and, as nestlings, will progress quickly to whole fish.
Hatchling herons and egrets do not gape and must have their mouths opened in order to be
fed. Often their mouths can be opened by the suggestive tap of a fish on the side of the beak.
Weaker, less active individuals may need to be force‐fed at first until they learn to respond to
the sight of fish.
As they become aware of their surroundings, nestlings will look to the cage floor for food left for
them by their parents. A food dish should therefore be left in the cage with young birds, to familiar-
ize them with the appearance of the food presentation. At feeding time, every effort should be
made to entice young birds to notice the fish dish that is in front of them and encourage them to
self‐feed. Fish slivers left in cages for free‐feeding should be presented in dishes 0.5 in. (1 cm) deep,
submerged in fresh water and covered with a light “snowfall” of calcium powder (Figure 17.4).
Young herons and egrets may begin self‐feeding at a remarkably early age, before their bodies are
covered with down. Do not underestimate the amounts they can eat – Black‐crowned Night‐
Herons in particular are voracious eaters that can eat their body weight per day in fish, distributed
across several feedings.

Nestlings­and Fledglings

Partially and fully feathered herons and egrets should be able to self‐feed. Nestlings can be intro-
duced to self‐feeding by having fish splashed in the dish in front of them (using a hemostat or
puppet), and by having fish tapped on the side of their beak and then splash‐dropped into the dish
when they open their mouths for it. Fish dishes should be checked frequently and refilled when
empty. There is no need to hesitate to graduate newly self‐feeding birds to whole fish as soon as
they will accept them.
It is important to perform follow‐up checks of a birds’ temperature if they ever appear sleepy or
fluffed up. Self‐feeding birds given a large meal of recently refrigerated fish may result in a drop in
body temperature as the bird warms up the meal it has just consumed, thus potentially increasing
the need for heat supplementation.