Four Dozen Predated in Two Years
(LIHUʻE) – Last week, researchers discovered the bodies of six endangered Hawaiian Petrels at a remote breeding colony in Hono o Na Pali Natural Area Reserve, Kauaʻi. All had been dragged from their breeding burrows by feral cats and partially eaten, including one incident that was caught on a monitoring camera.
“Unfortunately these incidents continue to happen with regularity on Kauaʻi,” said Dr André Raine, Project Co-ordinator for the Kauaʻi Endangered Seabird Recovery Project. “Feral cats are found all over our islands, even in the most remote and inaccessible regions. They are a significant threat to not only native seabirds, but a wide range of other endangered bird species.”
The Hawaiian Petrel is an endangered seabird found only in the Hawaiian Islands. Its populations have declined dramatically in recent years on Kauaʻi, where it faces a number of threats including being eaten by introduced predators such as cats. Several colonies of these birds are now being protected by seabird management projects, which includes the control of introduced predators.
“Introduced predator control projects are a vital part of seabird management, and have successfully decreased the number of introduced predators in remote seabird colonies in recent years” explained Dr. Raine. “However, as this incident shows, it only takes one cat to get into a colony, where it can then kill a large number of nesting birds in a very short period of time.”
Sheri Mann, the Kauaʻi Branch Chief for the DLNR Division of Forestry and Wildlife, commented, “Predator control efforts should be the last line of defense for these colonies. The fact that we have cats slipping through, highlights how dire the feral cat issue is on Kauaʻi and that control efforts solely in wilderness areas are not enough to fully deal with this problem. It will take a concerted effort by the island community as a whole to protect native species.”
Hawaiian Petrels come to Kauaʻi to breed from April to December and nest in burrows which they dig in the ground under native ferns and at the base of large trees such as o‘hia. At this time of year, they are incubating a single egg, and are extremely vulnerable to cats and other predators who can get into burrows to kill them.
“In the last two years, we have found the bodies of at least 48 endangered seabirds that were killed by feral cats and this represents just the tip of the iceberg,” explained Dr. Raine. “If we continue to have large numbers of feral cats roaming the landscape, the situation will only deteriorate for these beautiful and iconic birds. We can all help by encouraging responsible pet ownership, which includes keeping cats indoors and away from our native wildlife.”