Faith can be defined as the belief that something exists or is going to happen without having any proof of it. This belief is the foundation of a great number of religions, but also many behaviors in the animal world.
The way that Christianity speaks of Jesus as the Lamb of God who takes away the sins of the world is more than sufficient evidence that this animal's symbolism in relation to faith is incredibly significant. The lamb has a strong presence in Christian symbolism as an animal used for sacrifices.
The dove is undoubtedly the animal that is most closely related to faith, from the moment when this bird appeared to the Virgin Mary when she became pregnant. Since everyone knows how children are made, there is no doubt that the dove symbolizes the faith that God found a different way.
The camel is another animal that can be linked to faith. It spends much of its life in hostile environments, and only after a long walk through the desert can it access food and water. Camels need to have that faith that at the end of the journey they will have a reward, or else they will find it difficult to begin. In addition, it is an animal that also appears in the Old Testament, in stories such as that of the Magi of the East who travel to meet the God who has just been born.
It takes a lot of faith in your chances to be able to swim against the current and get to the highest point of the river. This is what salmon does. It never allows itself to be overcome by discouragement, and it symbolizes faith in your own strength despite having everything against you.
Similar to salmon, the goat also has faith that it will reach the top of the mountain. Otherwise it would not take the risk of climbing to such high heights with the possibility of losing its life. In this case what the goat symbolizes is not faith in a higher entity, but in achieving great goals.
The swallow is related to the proclamation of good news, and this annunciation is present in biblical texts as a proclamation of the coming of the Son of God. That is why the arrival of swallows is interpreted as a sign that positive things are going to happen. It gives us the faith that better times are coming.