WHAT is a fish? Federal Parliament was to tackle the tricky issue.
Legislation being debated this week would amend quarantine laws to insert a definition of a fish.
The Agriculture, Fisheries and Forestry Legislation Amendment (Export Control and Quarantine) Bill 2006 was to define a fish as "an aquatic vertebrate or an aquatic invertebrate but not a mammal or a bird".
In other words, prawns and barramundi yes, whales and dolphins no.
A spokesman for Fisheries Minister Eric Abetz said the change was needed because fish had previously not been defined in law.
The definition is not the sole change being made in the legislation.
It also tightens controls on fish export lines and introduces penalties for people who fail to properly prepare fish for export.
And it provides a legal basis for the Commonwealth to recover quarantine service fees from other government agencies.