The Zebra Stalker is the common form of the Gray Stalker which appears earlier in the game. They typically attack in small groups and the others don't seem to spawn until Aya gets near them or another has been killed.
While they are cloaked, they cannot be targeted directly, but they are far from vulnerable and may still take damage if you target a weapon or spell at their last known position. Running near them will cause them to become visible and attack, which can be avoided.
Group attacks like Combustion or shotgun shells are effective. Keeping a single stalker on stun lock using a weapon with a moderate-to-high rate of fire will prevent it from attacking the player. Combat Light and Riot Grenades are among the most effective attacks, since they cause PARALYSIS
Compared to other Stalkers, they are far from dangerous...