Haber Subjunctive

Question

One of the questions testing the present subjunctive of haber is:

Los pájaros irán donde ________comida.

With the correct answer being haya.

I understand the subjunctive being used in cases of hope, desire etc but I don't understand why it is used in this case rather than 'hay'.

Thanks.

Answer

Hola Martin
When we there is no certainty we use the subjunctive. I could use both the indicative and the subjunctive here:
Los pájaros irán donde HAY comida. 
In this case, the speaker know that the birds are going to a place where [he knows for sure] there is food. (certainty= indicative)
Los pájaros irán donde HAYA comida. 
Here, using the subjunctive, we need to assume that the speaker doesn't know whether there is or not food in that place. There is no certainty. 
I hope this helps,
Inma

Answer

Thanks Inma. That explains it perfectly. I was thinking only of the first case where there was certainty of food being there.

Answer

There is no uncertainty in this sentence or even implied by this sentence.  This is a statement of fact or something believed to be a statement of fact and I really think "Hay" is the better answer.  None of the usual trigger phrases are present, either.  I see what was meant about the birds going to a place where they think there is food which adds uncertainty but if that was so, the birds would just go somewhere else until they found food so there really is not any uncertainty about this at all. If the wording was something like "the birds to to where they think there is food" then it would be subjunctive.

Answer

Hola LloydI think you misunderstood about the notion of uncertainty. It is the speaker, not the birds, who expresses that certainty or uncertainty about places where there is food or there "might" be food.

Answer

Hey Lloyd, it's also about how the word "donde" can itself be a subjunctive trigger.  It depends on whether we know the specific place that "donde" refers to or whether the place is unknown.  (I remember reading about this somewhere on Kwiziq but it's tricky to look up links when you're using a phone).