Researchers estimate that numbers of storm petrels were once quite high on Kamaka Island, as a relatively large number of individuals were recovered from an archeological site on the island. However none have been seen on the island since 1922. Now, o<nly an estimated 250-1,000 mature individuals remain in the wild.<\/p>\n
Getting the birds to return required solving a serious problem: invasive rats that had driven the ground-nesting birds to local extinction by preying on their eggs, chicks and even adult birds.<\/p>\n
\u201cA majority of extinctions occur on islands with invasive species, rats as a primary cause,\u201d Sally Esposito, strategic communications director at Island Conservation, told Mongabay.<\/p>\n
Kamaka Island measures only 0.5 square kilometers (0.2 square miles), about the size of the Vatican City, and is uninhabited by humans. However, attempts to remove rats from the island failed in 2015, largely due to its steep and challenging terrain.<\/p>\n
In 2022, Island Conservation worked with ENVICO, an Aotearoa New Zealand-based drone company, to conduct more than 600 flights to spread rat poison across the island. As far as the team can tell from extensive surveying, the rats have been eradicated.<\/p>\n
Kamaka was an ideal location for this type of intervention, says Island Conservation, because it has very few land birds and no other small mammals that could be affected by the rodenticide. “No native species were harmed during the removal of invasive rats from Kamaka Island,\u201d Esposito said.<\/p>\n The conservation team also studied the birds\u2019 preferred habitat on Manui Island and used this knowledge to create optimal nesting conditions on Kamaka. The team installed solar-powered speakers playing recorded bird calls from the Manui colony and built \u201cluxury burrows\u201d equipped with cameras to monitor birds\u2019 activities.<\/p>\n \u201cWe\u2019re looking for ridge lines where they could access the site, and then we\u2019re also looking for certain vegetation characteristics,\u201d Wolf told Mongabay. \u201cYou want enough trees that are creating [ground] burrowing habitat, but at the same time making sure that there aren\u2019t too many trees that they can\u2019t access those sites.\u201d<\/p>\n The team also collected and planted native sedges and grasses while removing invasive trees to enhance nesting conditions.<\/p>\n Their monitoring equipment documented a gradual increase in storm petrel activity throughout this year. Initial sightings in April and May led to consistent visits a few months later, with the birds showing particular interest in the artificial nesting sites and areas near the acoustic equipment.<\/p>\n \u201cThe results of our social attraction efforts were quickly apparent,\u201d Thomas Ghestemme from the Ornithological Society of Polynesia (SOP MANU), a local organization that helped with the restoration efforts, said in a statement. \u201cPolynesian storm-petrels began visiting at the start of the nesting season and became regular visitors, while also spending time in the nest boxes.\u201d<\/p>\n However, actual nesting hasn\u2019t yet been confirmed. \u201cRight now, based on our review of all the camera trap data, we can\u2019t say how many individuals we had visiting the site. We can say how frequent they were coming,\u201d Wolf said. \u201cRight now, we\u2019ve only seen one at a time, so we know that they\u2019re coming relatively regularly during the breeding season.\u201d<\/p>\n Community involvement proved crucial to the project\u2019s success. \u201cWe are committed to working with the island communities that provide in-depth knowledge of these environments,\u201d Richard Griffiths, head of operations for the South and West Pacific at Island Conservation, said in a statement. \u201cWe simply could not have completed the Kamaka project without their time, skills, expertise, and relentless energy.\u201d<\/p>\n The project is part of the Island\u2013Ocean Connection Challenge, which aims to restore 40 island ecosystems by 2030.<\/p>\n Preventing extinctions has larger ecosystem benefits, Esposito said. \u201cThe return of nutrients from seabirds benefits the soil, which runs off to the marine environment and builds climate resilience, secures livelihoods, and human health.\u201d<\/p>\n