I agree with Jordan - it's present simple subjunctive. Basically, this means the main verb doesn't change at all. English speakers do use it - far more commonly than they'd admit - but as with other grammar forms explaining it is a different matter. You can understand "whether it be" as meaning "it doesn't matter whether it is a..." The first one looks far neater and clearer, don't you think? ;)

I believe that gramatically, whether it be... is actually using the subjunctive form of the present tense. Its really simple in english to use this tense actually. Coming from Chinese, this might be a difficult tense, but in speaking, you'll never need it. The point of the subjunctive tense is to express a bit of subjectivity. For example. indicative (regular speech) I was shopping. Subjunctive (grammar stuff useful for essays but generally not so important) If I were shopping... Its the same for I, you, he, we, they etc. Also, most native english speakers dont know how to use this tense properly.

You can use "whether it be" OR "whether it is" in any situation. They both mean the same thing. ^-^ BUT, you wouldn't say: "whether it is bird", you would say: "whether it is [a] bird". Even though I speak English, I'm not sure why there is a "be". hahaha (: Hope I helped! c:

"Whether it be bird..." is a little stilted and not something you would be likely to hear in conversation. "Whether bird, fish or beast... " is simply and would work just fine.