Ulva Island, is part of Rakiura National Park and managed by the Department of Conservation as an open island sanctuary free of introduced predators. Rats were cleared off the Island during the 1990's.  

Public access is allowed during the daytime. Overnight camping is not allowed. A marine reserve established in 2004, ensures that approximately half of Ulva Island's coastline is protected.

Key conservation work on Ulva Island is based on predator control, as rat re-invasions from surrounding areas is an ongoing threat, and on rare occasions a deer may swim from nearby Stewart Island. 

Without browsing mammals the forest can reach and maintain its natural state and without introduced mammal predators, native and endemic birds can grow and thrive in a safe environment. Keeping introduced browsers and predators off the island is a major priority.  

Rare and threatened native bird releases and planting of native flora is aimed at continuing the richness of Ulva Island's biodiversity.

Birds released on Ulva Island, since the removal of rats include:

  • South Island saddleback
  • Stewart Island robin
  • Yellowhead (mohua)
  • Stewart Island rifleman

Kiwi were put on Ulva Island several decades ago and three years ago some of Ulva Island's kiwi were moved to Oban, Stewart Island and replacement birds put on Ulva Island from Mason Bay.

Rat Invasion July 2010

Of significant note, in July 2010 rats were found on Ulva Island and increased trapping in later months showed that rats were breeding. The Department of Conservation carried out aerial poisoning on 18th August 2011 and 20th September 2011. The poison drop, had an impact on the many rare and endangered birds on Ulva Island and it will take several years for the bird populations to reach levels experienced prior to the rat reinvasion and poison drop. Limited bird monitoring work was carried out by the University of Otago.

In April 2012, the Department of Conservation release 14 weka onto Ulva Island from nearby Bench Island to boost the population.