Auckland Zoo keeper Deja Rivera writes about her time in Samoa, searching for the critically endangered manumea
In collaboration with Rebecca Stirnemann (Project Coordinator for the Manumea project) and Moira Pryde (Department of Conservation scientist) and funded by the Auckland Zoo Conservation Fund, I was involved in research trying to determine the population size and distribution of manumea throughout Samoa.
This involved the deployment of over 70 sound recorders, each at least 500 metres apart, across various survey sites on the two main islands of Samoa, Upolu and Savaii. Once deployed, the sound recorders were left to record simultaneously for two weeks.
The main criteria for the survey sites was large tracts of forest, of which few remain in Samoa. The majority of Samoa's remaining forests are disturbed by human activity such as logging and the introduction pest flora and fauna species.
Each site was also surveyed for quality of forest by answering the following questions for each sound recorder deployed: Is it primary or secondary forest? Are there any native fruiting trees that are a food source for pigeons such as Maota (Dysoxylum maota) or Mãmãlava (Planchonella samoensis)? Are there signs of introduced pests such as pig rooting and presence of trees like Pulu Vao (African rubber) and Fa'apasī (African tulip)?
All of the sites were surveyed by foot and required traversing very steep terrain with dense vegetation in extremely hot weather. A typical day of surveying would consist of us hiking about 8 to 10 kilometres in 30 degree heat, which doesn't sound like a lot of ground covered, but we only averaged about 1km/hr! I can honestly say, I never sweated so much in my entire life and was completely astounded by the optimism, agility and machete skills of our local guides in these conditions.
Many of the younger guides took a great interest in helping us deploy the sound recorders and learning how to use the GPS units. Although, none of the locals really needed them as they were all able to navigate their forest like the back of their hand, often following the marked track to a T without even referencing the GPS.
Sadly, during the three weeks we spent deploying sound recorders, I never actually saw a manumea and only heard it call a few times, which could in part be due to very few of the surveyed sites having large tracts of primary forest abundant with native fruiting trees. Instead, most of the sites were highly fragmented and predominantly secondary forest riddled with introduced pests.
These preliminary findings show the impact habitat loss and degradation is having on this critically endangered bird. Thankfully, one of the villages we worked with, Falease'ela, is acutely aware of the need to restore Samoa's natural environment. The village has formed the Falease'ela Environment Protection Society (FEPS) and are using funds provided by GEF (Global Environment Fund) Small Grants Programme to plant native trees in the watershed area that will ultimately provide more habitat for Samoa's native birds.
In conjunction with FEPS, local couple, Olsen and Jane Va'afusuaga, have founded "Lalotalie ECAT Ventures", an Eco-Cultural Adventure Tourism venture that educates visitors about the village's conservation initiatives while providing guided tours up the Liua le Vai o Sina River.