Importance of octopus fisheries in the Pacific
Globally, small-scale octopus fisheries have an estimated landed value of USD 2.3 billion, with a total annual catch of 88,000 tonnes (t) (Willer et al. 2023). In the Pacific, estimates for the production and value of these understudied fisheries are hard to find, but national studies provide examples emphasising their contribution. For example, an estimated 1,458 t of octopus was landed per year in Samoa between 1950 and 2010, 1,355 t of which was for subsistence (Lingard et al. 2012). In Fiji, 90 t of octopus are reported to be produced every year (FAO 2024) – a quantity that may be below actual catch figures due to the subsistence and unreported nature of many octopus fisheries. And, in American Samoa, Octopus cyanea makes up 5% by weight of all species caught for subsistence (Craig et al. 2008; Sauer et al. 2021).
Women play a crucial role in octopus fisheries (BatailleBenguigui 1988; Pinca et al. 2009; Williams 2015). In Fiji, 78% of women across 11 provinces were found to glean for invertebrates (Thomas et al. 2021) Additionally, in the region, women take part in gleaning more than other fishing activities (Williams 2015). Since women are more active in gleaning for invertebrates than men, any declines in health of invertebrate stocks, including octopus, are likely to disproportionately impact women’s livelihoods and their contributions to household income.
Despite the socio-economic contribution of octopus fisheries in the Pacific, knowledge of their stock statuses is limited (Gillett and Tauati 2018; Sauer et al. 2021). In this article, we intend to build understanding of octopus ecology, biology and identification. Furthermore, we outline protocols to measure octopus length, weight, sex, maturity status and age – all of which are variables required to create parameters needed in length-based stock assessments, working towards improved octopus fisheries management in the Pacific.
Octopus classification and distribution
Octopuses belong to the order Octopoda, globally comprising around 300 species. It shares the class Cephalopoda with squids, cuttlefishes, and nautiloids. A review by Loganimoce et al. (2023) reported that 23 species of octopus across 11 genera were documented from the tropical Pacific (Loganimoce et al. 2023). While not all species are important to fisheries, it is worth noting that some of these species are endemic to the region (Norman et al. 2005).
Octopuses are known to be fished in 19 Pacific Island countries and territories (Smith 1992; Dalzell et al. 1996; Haws 2006; Pasilio et al. 2013; Gillett and Tauati 2018; Gillett and Fong 2023; Loganimoce et al. 2023; FAO 2024), but only nine of these have octopus capture production reported in the FAO Fisheries and Aquaculture Yearbook between 2017 and 2021 (FAO 2024). No information could be found about modern octopus fisheries for Niue and Pitcairn, but there is historical evidence of octopus fishing activities in Niue (Ryan 1981).
Two species are known to be fished for food in the Pacific. The most widely fished species is the big blue or day octopus, Octopus cyanea, and to a lesser extent the white-striped or night octopus, Callistoctopus ornatus (Table 1; Loganimoce et al. 2023).
Although Octopus vulgaris is a commonly fished species in tropical to temperate waters globally (Sauer et al. 2021), Figure 2. O. cyanea on sale in Suva, Fiji. Image: © Pauline Bosserelle, SPC. it has only one recorded sighting in the Pacific islands (Koshida et al. 1986). Today, O. vulgaris is thought to be a species complex made up of at least six different cryptic species (Söller et al. 2000; Leite et al. 2008; Amor et al. 2015; G. Gleadall 2016). Of these six, Octopus sinensis and Octopus tetricus are found in the wider Pacific; they are also found in the Eastern China Sea (G. Gleadall 2016), and south-eastern Australia/northern New Zealand (Amor et al. 2017) respectively. The presence of species from the O. vulgaris complex in the Pacific cannot be ruled out completely as the cryptic nature of these animals leads to misidentification (Taylor et al. 2012).
To read the full article by Hannah Gilchrist, Indah Rufiati and Epeli Loganimoce, please check this link
