The risks posed by aliens are a hot topic for consideration in many international meetings. As an industry we possibly move more individuals of more species around the world than any other. Thus potentially we may face greater scrutiny than our economic size would otherwise dictate.
Aliens are any species that is moved out of their natural range.
When this happens there are a number of possible outcomes. The individuals transferred just die. This could be because of a number of reasons for instance the habitat may be entirely unsuitable or the number of specimens introduced are insufficient to create a successful breeding colony. The species may colonise the area to which it has been introduced but not spread any further. The species thrives and rapidly colonises a wide area.