More Than a Fishery: Ark Clams (Piangua, Anadara spp.) as Cultural Keystones and Gendered Economic Lifelines in Coastal Tropics

Ark clam fisheries of Anadara tuberculosa and Anadara similis , locally known in Colombia as piangua , play a key role in supporting communities along their distribution. Nevertheless, piangua faces increasing social–ecological threats. This study investigates the cultural and economic role of piangua in Bahía Málaga, Colombia. Utilizing socioecological methods, the study analyzed livelihoods, gender disparities, and ecological perceptions of piangua in the community. This methodology included semistructured interviews ( n  = 48) and the estimation of both a cultural importance index (CII) and the Herfindahl–Hirschman economic diversification index (HHI), as well as an assessment of local perceptions of piangua threats and availability over recent decades. The results revealed piangua as culturally vital, where 56% of respondents scored CII values >0.6 (max 1.0), with women showing higher cultural attachment. Fifty-four percent of women relied on piangua as their primary income source; however, men earned twice the monthly income (US$363 vs. US$183 ) through other extractive activities. The HHI results indicated moderate-to-high income concentration (0.4–1.0, higher values indicate greater dependence on a single-income source). Although women engaged in multiple income activities, their livelihoods remained moderately to highly concentrated. Over 90% of respondents reported declining piangua harvests since the 1970s, identifying overexploitation and mangrove degradation as key threats. Piangua sustains cultural identity and livelihoods, but risks collapse without addressing current pressures through inclusive management that integrates local knowledge. Our approach identifies piangua as a cultural keystone species and key economic resource, offering a framework for conserving both biological and cultural diversity.