A murder of crows?

I love the subset of collective nouns known as the terms of venery. These are collective nouns specific to a particular group of animals. Some of the more inventive examples are: a murder of crows, a crash of rhinos, a mischief of mice, and a puddling of ducks (specifically swimming ducks).

Is there a standard for these group names and is there a central reference for them as with other zoological taxonomy? I can see in the Wikipedia articles that the practice has its origins in Medieval Hunting tradition, but the Kangaroo (Mob), for instance would have been unknown at that time, so how do new collections come into being?

If you have interest in this subject, James Lipton's An Exaltation of Larks is the chief reference work.

What you'll learn is that there are usually two (and sometimes three) group nouns for animals and birds. There will be a term of venery of a classical nature, often coined by hunters or gamekeepers (a murder of crows, an unkindness of ravens, a parliament of owls) and a general term used by laypersons (flock, herd).

Expert English users will be familiar with both sets, and general users will have a vague sense that there are such terms, but know very few of them.

Apparently the original source from which most of these names came is the Book of St. Albans, originally published around 1480.

Wikipedia states that:

A modern collection is James Lipton, An Exaltation of Larks, Penguin Books, 1968, ISBN 0-670-30044-6.

There is certainly no “standard” — no equivalent to L'Académie française — to regulate these matters! They are just phrases that catch on because they meet a need, or because people like the sound of them, or in the same way that clichés turn into idioms.

Most are lost in antiquity, of course, but I can shed some light on mob of kangaroos. In Australian English, mob is a general word for any kind of flock, herd or drove, so when writers needed a collective noun for kangaroos mob was the obvious choice.

New collective nouns arise all the time. From the metonym panel we get panel of experts. From the rare usage of shower to mean contemptible person or people we get shower of bastards.