What does "a threat of red ink at the bank" in the following context mean?
A deep chesty bawl echoes from rimrock to rimrock, rolls down the mountain, and fades into the far blackness of the night. It is an outburst of wild defiant sorrow, and of contempt for all the adversities of the world. Every living thing (and perhaps many a dead one as well) pays heed to that call. To the deer it is a reminder of the way of all flesh, to the pine a forecast of midnight scuffles and of blood upon the snow, to the coyote a promise of gleanings to come, to the cowman a threat of red ink at the bank, to the hunter a challenge of fang against bullet.
I know the meaning of "red ink". But in this context, it seems to me there is a metaphorical meaning to the bold part. Isn't it? Also, the meaning of "bank" here is confusing: is it something related to money or to land? The second is what first comes to mind because the text is about land and ecology.
I think the text is tricky. The writer is talking about land and environment thereby he tries to say what he intends to say through expressions which have a taste of environment. For example the "red line at the bank" seems to bring to mind the blood of cows killed by the wolf.
Also notice the meaning of "bank" in the context. If you take "bank" here to mean "the financial establishment", you cannot reject that it has at least a hint to the second meaning of "the land alongside or sloping down to a river or lake." Those who put the question on hold seem not to consider how delicate the text is.
2 paragraphs later in the text we read: "When she climbed the bank toward us and shook out her tail, we realized our error: it was a wolf." Here "bank" is used in the second sense. So, I say, the main thing the writer intend to say is, of course, that the sense the howl has for the cowman is losing money; but the writer at the same time wants to refer us to the cause of that money loosing, which is cows being killed by the wolf on the bank leaving red ink (blood).