The diagram on the left, derived from the Tree of Life web project, traces the lineage of our rookery birds. Only the branch of each family that leads to our birds is followed. There may be some surprises for the casual observer. Looking first at the three main “trunks” of the Class Aves, which includes all birds, we see that. compared to the egrets, the familiar waterbirds like ducks, geese, and swans are on a completely different “trunk” or subclass. They are much more closely related to chickens than they are to egrets.
The Neoaves, an incredibly diverse subclass that contains most bird species, includes an Order that is vaguely called “Water Birds”. This is the branch of the tree that leads to the herons. Note that, surprisingly, this branch does not include the cranes, which most people would say resemble herons in their long legs and necks, graceful stride, and general personality. Nevertheless, the Gruiformes are their own separate, ancient and fascinating tribe.
Following the branch to the “Water Birds” Order, we find the next branching point to be the Pelicaniformes Family. This makes sense as a line to the Heron cousins. Certainly more than Penguins would.
Finally, we come to the Pelicaniformes, in which all the the rookery birds are members in good standing.
Notice that our anhingas are very closely related to cormorants. You will see that both anhingas and their cormorant cousins dive for fish, then hold out their soaking wet wings to dry. This is because, unlike ducks, their feathers are not oiled to repel water.
Notice too that the ibises and herons are closely related branches. Hence our logo is eminently appropriate for an Heron and Egret Society.
You might now be asking yourself, where are the egrets?
There is a related very popular question, what is the difference between egrets and herons anyway?
The answer to this question is: no difference at all. Some Ardeidae have popular names that end with “heron” (like little blue heron, Egretta caerulea) and others end with “egret” (like snowy egret, Egretta thula). These popular names are quite inconsistent. For example, Audubon himself referred to the snowy egret as the snowy heron.