Which species is threatening the natural wildlife on the galapagos islands?

Galapagos islands are groups of island in the pacific ocean that are known to have a wide range of  native animals such as giant tortoise that found no where else on earth. These native animals helped Darwin in the development of the theory of natural significance which attributes to the biological significance of the Galapagos islands. Human species is a threat to the natural wildlife on these islands mainly due to poaching and destruction of natural forests that destroys habitat and also impacts negatively on biological diversity of living organisms.

1.989×10^30 kg is the weight of the sun.

Could you elaborate?