I think that William Blake summed up the reverence of the tiger in his poem of the same name:- "Tiger, Tiger, burning bright, in the forests of the night, what immortal hand or eye, could frame thy fearful symmetry?". In this case the tiger and everything else within the painting has been used as a heavy symbolism to its religiously connected title.
To truly understanding this painting (in my humble opinion) you really need to understand what a Pieta is.
Famously Michelangelo created one of the most beautiful Pietas which I have written about previously and you can read about it here
A Pieta, is a religious depiction of the virgin Mary cradling the dead body of Jesus. This is one of three iconic poses for the sorrow of Mary used by artists in the christian realms. The others being Mater Dolorosa (Mother of Sorrows) and Satbat Mater (here stands the mother).
Wittfooth cleverly interprets the image of the Pieta to something stoic with his use of animals.
The tiger representing Mary, also being the symbol of a leader carefully cradles the heron lying dead in its paws. The heron, along with being the symbol of Jesus also represents gracefulness and elegance. The tigers expression is that of displeasure with its ears laid backwards. Surrounding the front of the car are pink roses, representative of gratitude, appreciations and gentleness, almost a thank you for the herons sacrifice. From the car window grow poppies, these have been used to represent death and being at peace, while in the distance a faint heron flies off, almost ghost like.
There is something to be said for the car that the tiger is lay on. This is a decaying model of current society with the death of a dying religious belief lay on top of it (again only my opinion, I don't wish to spark a topical debate about the relevance of christianity in the modern society).
In other pieces of Wittfooth art, he presents to his audiences an almost post apocalyptic world where smaller animals represent creep and linger around burning forests and building, where the larger animals appear to be much calmer in their actions, and while Pieta II follows his theme of animals based in the midst of a beautiful decay, the piece has a resonance of the title which echoes its religious origins.