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In May 2015, 74 line transects in three different habitat types (plantation, mixed crops, urban) were surveyed on Upolu and Savai’i islands, Samoa, with an aim of estimating the population size, density and distribution of two invasive bird species, Common Myna (Acridotheres tristis) and Jungle Myna (Acridotheres fuscus). Based on the available literature, the surveyed habitats were identified as preferred foraging habitat for the two myna species. The three habitats make up 24.9% of Samoa’s land area. Survey data were analysed using the Distance program. It was estimated that the population of myna birds occurring in the plantation, mixed crops and urban habitats of Samoa is approximately 158,995 (+- 29,588). Approximately 130,030 (+- 19,837) myna were estimated to live on Upolu and 28,968 (+- 9,751) on Savai’i, across the three habitat types. Survey results also revealed that both species show a significant preference for urban habitat. Jungle Myna were estimated to be the most numerous (population estimate: 133,925 +-24,321), occurring on both islands and in all surveyed habitat types. Jungle Myna seem to have saturated the urban habitat available in Upolu and therefore have proceeded to colonise plantations and mixed crops adjacent to urban areas. Common Myna (population estimate: 23,367 +- 7,612), having reached the shores of Samoa ca. 20 years later than Jungle Myna, show highest density in urban environments. They are concentrated in the north-west section of Upolu, with only a few individuals observed on the east coast of Savai’i.

Dugong dugon are the last extant species in the Family Dugongidae and are listed as Vulnerable to extinction by the IUCN Red List. The dugong population is believed to be in decline globally. Throughout its range, relic populations remain and are separated by large areas where populations have disappeared (Marsh & Lefebvre 1994). The degree of the decline of numbers or fragmentation of its range is not known for any country. For many countries the only information available is from incidental sightings, drownings and anecdotal information. The Pacific region supports the world's largest remaining population of dugongs (Marsh et al. 2002). Dugong occur in most of Melanesia, Papua New Guinea (PNG), the northeast and east coasts of Australia and as far east as Vanuatu.. The current status of dugongs is unknown throughout the region (Marsh et al. 2002) and information on dugong distribution and abundance is outdated or non-existent. It is likely that dugongs are widely distributed in small numbers in much of PNG. the Solomon Islands and Vanuatu and that larger numbers occur in the Papua New Guinea waters of Torres Strait. Marsh et al. (2002) states that their reliance on relatively shallow water seagrass beds for food, limits the ability of dugongs to travel between islands and continents that are separated by extensive areas of deep water. For this reason, many island populations become essentially isolated, making these populations especially vulnerable to extinction.