Common Ground Device
Tribbles are likely to be first encountered by the player as a loot drop item (like the standard 'dotson' variety tribble shown in the icon above). They originated from Iota Geminorum IV and are a non-intelligent life form. They are equippable in a Device slot. "Standard" tribbles provide an out of combat bonus to hitpoint recovery rate. They are not a consumable item and can be used indefinitely. The standard loot drop tribbles are just the tip of the proverbial tribble iceberg, however...
(see the Tribble Breeding Chart at the base of this page for the rest of that iceberg)
"Using" a Tribble
Just as they did in the episode "The Trouble with Tribbles" in Star Trek TOS, tribbles in STO multiply. Quickly. And easily. All that's required for tribbles to breed is for a tribble and an item of food to be present in the same location. This location can be in a player's inventory, or bank vault - or even the Device power bar. Each newly created tribble replaces one food item. Depending on the type of tribble, and the type of food it consumes, offspring may be "standard" tribbles (i.e. the same as loot drop tribbles)...or they might be one of the rarer special varieties!
Rarer foodstuffs (i.e. 64% and 72% hit point foods as opposed to that available from the ship's Replicator) are what produce these rarer tribble forms. Such rare tribbles are much sought after because they confer long lasting (60 minutes) minor buffs to Damage Resistance, Damage dealt, or Health Regeneration - and in some cases, even two buffs simultaneously.
Tribbles all share a common species name : Polygeminus grex.
Each tribble variant also has a subspecies name (shown by right clicking the tribble and selecting info) e.g. Polygeminus grex stahl, Polygeminus grex mattson. Every named subspecies has a unique appearance. 25 tribble subspecies are known to exist, with evidence for a 26th as yet unimplemented variant.
All tribble subspecies can be bred by players, with the exception of Tribble of Borg and Polygeminus grex rivera which is a special triple buff tribble only available with certain purchases of STO.
Tribble Breeding Chart
The following chart lists the 24 breedable tribbles in the game arranged by breeding generation, along with selected lists of foodstuffs required to produce them. As can be seen, the occurrence of any given tribble subspecies is not random, and is in fact directly determined by which type of food is fed to any given tribble type.
e.g. having a Deangelo tribble and 1 unit of Romulan Ale in your inventory will always produce a Mattson tribble
What the chart does not show is the consequences of feeding buff-level tribbles with incorrect, or lower quality foods : this tends to produce "throwbacks" to lower order tribbles and can therefore be ignored for the purposes of this chart which is intended to show only those breeding paths necessary to produce the various buff tribble subspecies.
Also omitted from the chart is Polygeminus grex rivera, the special triple buff tribble (bonus item included with certain purchases of STO). Those lucky enough to already own a Rivera, however, might be interested to know that is capable of producing all of the 5th Generation tribbles listed below, and from exactly the same food given to the 4th generation tribbles on the chart (e.g. Rivera + Blood Wine = Deangelo, and Rivera + Vulcan Spice Tea = Stacy, just as with the Henry and Nix subspecies respectively).