"Are they little birds?"
Translation:Jsou to malí ptáci?
No that is not possible. This is the "to je"/"je to" construction where you have "to je" followed by something. And that something can be of any gender. And if you also change the verb acording to the person and number, that something can be really anything.
To jsem já.
To jsi ty.
To je velký pták.
To jsou velcí ptáci.
It is always to.
Grammatically, this is a noun predicate noun. Czech always uses "to" here for the subject.
You use "ti" agreing with the noun "ptáci" as an attribute: ti ptáci, ti velcí ptáci.
You can use the attribute even in the predicate:
To jsou ti ptáci. (Those are those birds.)
To jsou ti velcí ptáci. (Those are those big birds.)