The best Earthquake warning system I have had experience was chickens. I believe the ones responsible for the warning were a rare breed of chickens called Black Astralops or Black Astralopes. (I have seen it spelled both ways.)
Quite a few people have insisted that this breed does not exist because they assume that I must be misspelling the name of another breed called Black Astralorps. Those are an Australian breed and may be related to the Black Astralopes. They look similar, but are not exactly the same.
All of my 4 Black Astralope hens had spurs that were bigger than some roosters I have seen. All of those hens were enthusiastic about using their spurs in the right situations, so they are pretty tough birds when they feel the need to be.
I babied my Black Astralope hens a lot, so they were very cuddley with me and any people they were properly introduced to. I could hardly believe the change that came over them when they felt the flock, or eggs needed to be protected from my dogs, for example.
I had a couple of other breeds of chickens as well, but I never did like them much. They were not nearly as smart and interesting as the Black Astralopes.
There were earthquakes in the area before I got the Black Astralopes and the other kinds of hens never reacted to them ahead of time.
The first big earthquake after I got the Black Astralopes was different.
In the morning of the day of the earthquake all of my hens disappeared from their yard. I saw the empty yard and ran out to see what was going on. I had ideas of a chicken thief or horde of raccoons or dogs making off with the whole flock.
I looked in the coop. There all the chickens were, sitting on their roosts and in their nesting boxes. It was bright daylight, so they were not being faked out by no sun.
I tried picking one of the Black Astralopes up and carrying her out into the yard. She squirmed and squawked until she I let her go and she ran back into the coop with the rest of them.
The chickens mostly stayed in their coop for the rest of the day. The earthquake came in the early evening. The chickens came out for a little while after the quake before they went back to bed for the night.
The chickens roosted in daylight again before another big earthquake, so it was not a coincidence.
That was many years ago and those chickens are long gone. I do not know if it was a particular talent of that set of Black Astralope hens or not. As soon as I have a place to put them, I want more Black Astralopes, however. I live in an earthquake prone area. I will take all the possible warning I can get.