In the film, the island people have many items depicting hares. At the begging we see a chocolate hare in the candy shop as well as a little girl that is drawing a hare. When Howie says rabbit, he is corrected and told it is a hare, not a rabbit.
We also see a hare later in the film when Howie goes to exhume what he was told is Rowan’s body. When he opens the casket all he finds is a dead hare. When looking at possible explanations and symbolic meanings of hares, I found that there are some Pagan sects that regard hares as a symbol of foolishness or trickery. This ties into them fooling Howie on several occasions like getting him to come to the island to search for Rowan, tricking him into thinking they were going to sacrifice Rowan, and having dress as the fool before the sacrifice.
Hare Information Received From: http://homepages.uwp.edu/martinm0/Spring2007/167/symbolism_of_rabbits_and_har.htm