This is not the only reason for the dramatic fall in the number of swiftlets. Mining in caves, destruction of the rain forests, and collection of guano have also disturbed the birds 'habitat; all of these have been a blow to the existence of the swiftlet.
金絲燕銳減的原因其實不只一端，當地政府在石灰洞採礦、熱帶雨林的破壞，和收集鳥糞干擾了燕子的作息等等理由，都對金絲燕的生存造成衝擊。