Just because something is cute and snugly does not mean it isn’t dangerous.
Nothing is better evidence of this then perhaps the most dangerous [fictional] invasive species:
A Tribble from Star Trek.
Tribbles are a purring ball of fur that snuggle and make people feel good, including Vulcans. The creatures were introduced in the Star Trek TOS episode Trouble with Tribbles; returned in the Animated Series episode More Tribbles, More Troubles; had cameos in Star Trek III: The Search for Spock and Star Trek Generations; and appeared again in the Star Trek: Deep Space 9 episode Trials and Tribble-ations.
An invasive species is an animal which is introduced into a completely new environment to the detriment of indigenous species. Examples include Zebra Muscles in the Great Lakes, Asian Carp, or Pythons in Florida.
The US Congress described the dangers caused by invasive species as follows:
When environmental conditions are favorable, nonindigenous species become established, may compete with or prey upon native species of plants, fish, and wildlife, may carry diseases or parasites that affect native species, and may disrupt the aquatic environment and economy of affected nearshore areas;
16 USCS section 4701(a)(2).
Tribbles lack the gross factor of Zebra Muscles or the terror of a 17 foot snake surprising a birthday party in Florida. While it is extremely unlikely Tribbles will play any role in Star Trek Into Darkness, Tribbles would pose a greater environmental threat to an entire planet than any of the current invasive species on Earth.
Tribbles are born pregnant and give birth when fed. While not as messy as getting a Gremlin wet, the mere introduction of a Tribble in an ecosystem would cause an immediate threat to the food supply and cause a Tribble population explosion. Even if hawks, alligators, lions, sharks and every predator on Earth developed a taste for Tribble, they would not be able to keep up with Tribble reproduction.
There would also be challenges in mobilizing Tribble slaughterhouses and the industrial capacity to keep up with the rate of reproduction.
The United States Government and States have fought invasive species a number of ways. One is prohibiting conduct that introduces the animals into the ecosystem, such as the discharge of untreated water in the ballast tanks of foreign cargo ships in US waters. Other “hands-on” remedies include adding rotenone (a fish kill agent) to waterways in fighting Asain carp.
The Klingons in Star Trek The Animated Series created a Tribble predator called a Glommer to hunt and eat Tribbles.
Klingons creating a creature to hunt an invasive species carried a fair amount of risk, because they were adding another animal to the environment.
While the Glommer could have been engineered to only eat Tribbles and die when the food supply was exhausted, such a plan is not comparable to adding rotenone to a lake to kill Asian carp. Simply put, there is risk in adding another animal to the mix.
However, the Klingons did send a fleet to destroy the Tribble homeworld (Referenced in Trials and Tribble-ations). This plan for Tribble-cide was more in line with a traditional “fish kill” to eliminate an invasive species…if the invasive species were as cute as baby seals.
One option is to outright prohibit ships bringing Tribbles to Earth, much like the United States Congress (and the Coast Guard) prohibiting ballast water from being discharged in US waters from international shipping.
This plan would require Star Fleet’s equivalent of the Coast Guard conducting vessel inspections of star ships in orbit prior to any cargo being sent to the service. There also might be a technical solution of programming transporters to not beam Tribbles to Earth.
Another option is to classify Tribbles as exotic pets that are dangerous wild animals (like a ferret with rabies) and order the animals destroyed. (See, Raynor v. Maryland Dep’t of Health & Mental Hygiene, 110 Md. App. 165, 182 (Md. Ct. Spec. App. 1996)).
The Federation most likely enacted laws prohibiting the introduction of Tribbles to Earth, unless they had been “neutered.” The evidence for this “middle-ground” regulation were 1) the Tribble cameo in Star Trek III on Earth in the bar where McCoy was attempting to book a flight to Genesis and 2) a child is seen with a Tribble when the Enterprise-D is crashing in Star Trek Generations. There was no evidence later in Star Trek III of a Tribble population explosion and remediation efforts or the Enterprise-D survivors cooking Tribbles for food while awaiting rescue.
Further evidence for the “altered” Tribbles theory comes from More Tribbles, More Troubles. Cyrano Jones poorly attempted to genetically alter Tribbles to not reproduce, which ultimately Dr. McCoy corrected to create “safe” Tribbles that reproduced at a much slower rate. While this logic is based on the lack of a Tribble population explosion, it is a logical deduction given the fact a Tribble was present on Earth without incident in Star Trek III: The Search for Spock or Star Trek Generations.