In Journey to the West, why do monsters always know the news of Tang Priest's master and apprentice?

There is a famous song with a famous lyric called "Your Majesty invites me to visit the mountains". What do you think Xiaoyao is doing patrolling the mountain?

Throughout the whole Journey to the West, the Tang Priest and his disciples encountered monsters in the following ways:

First, I accidentally ran to the monster's cave (at least under the monster's nose), including Wanzi Mountain, Pansi Cave (and the temple behind the centipede essence), Xiaoxitian and Qingniuguai. Except for Pansi Cave, most of them are disguised as temple pagodas to lure passers-by, but they can't be said to be aimed at Tang Priest and his party.

Second, when people reach the boundary, but there are demons nearby, they are removed. One characteristic of this kind of monster is that it doesn't intend to eat Tang Priest, such as Kannonji, Chechiguo, Jisai, Zhu Ziguo, Wuji, Nvguo, Bhikkhu, Jingpingfu, Yuhua, Tianzhu and so on, and this proportion is the most. Of course, there are also some places where there are no monsters at all. Let's count them in this range, such as armed clearance.

Third, there is no other way but to remove the monster obstacles in the places that must pass on the westbound road, such as Tongtianhe, Heishui River, Huoyan Mountain, Shituoling and Qijue Mountain. In fact, the cause of the Mount Qijue is the above category, but it also ends in this category.

Fourthly, as I said at the beginning, I was just passing by, but I was discovered by the monster-not the monster itself, but by the little demon below it while patrolling the mountains, such as Baihuling (Bai Gujing), Huang Fengling, Pingdingshan and Yin Wu Mountain. In particular, white and gold horns and silver horns, white didn't "think of eating the meat of Tang Priest" until Tang Priest came. There was only one painted picture of the Golden Horn and the Silver Horn, and he didn't go up until he caught Pig Bajie. They didn't know they had arrived until they met the Buddhist scriptures team. The old gentleman said that Guanyin seconded a Jinjiao and a silver horn, but do you think the dialogue between these two monsters looks like Guanyin arranged a task? This matter is in doubt.

Speaking of it, there are only two places on the monster road, Mountain No.1 and the bottomless pit. But do you think Hon Hai-er and the mousetrap are concentrating on waiting for the Tang Priest to take the bait? I am afraid not. Ambush makes no difference. Rat spirit ate some young monks and took the Tang Priest away.

There is also an alternative, that is, the true and false Monkey King. Liu er, the macaque is here to see you. This should be someone else's ability. They can hear it no matter how far away, so they heard the whereabouts of Tang Priest.

Then tell me, among these monsters that Tang Priest and his party met, besides Liu Er's macaque, who else knew their whereabouts long ago?