Climate change: A pointer to increased small-scale fisher drowning deaths

food security and livelihoods of about 40 million people living in its basin [30, 31]. The intro- duction of non-native Nile perch into Lake Victoria in the 1960s precipitated rapid growth that brought migration, infrastructure development, and fish international export markets to lakeshore communities beginning in earnest by the 1980s [32–34]. The more recent decline of the Nile perch fishery has given way to expanding fishing effort to harvest omena [35]. We focus our study in the Kenyan side of Lake Victoria (Fig 1) where the lake provides for at least 76% of national fish catches and 0.4% of the country’s GDP according to official fisher- ies statistics [37], with estimates suggesting this may be a substantial undervaluing of the fish- ery [38]. The fishery in Lake Victoria provides direct employment to at least 48,000 fishers within Kenya’s sector of the lake [30]. Sampling and data collection This study utilized secondary data from the 2020 Lake Victoria Frame Survey to design the sampling strategy [30]. The Frame Survey is a biennial census-based approach in which fishing effort data (fishers/crew, vessels, and gears) is collected on all operators in designated fish land- ing sites. The survey also collects supplementary fishing information such as fishing trip dynamics, gear operation and socio-demographic information on fishers and landing facilities. The Frame Survey 2020 included a specific question on the number of fishers that had drowned within each landing site in the year 2020. The Frame Survey results indicate there

were 268 incidents of fisher drowning across 83 landing sites in Kenya. While the frame survey had statistics on drowning incidents, it did not provide information on the socio-demographic profile and occupational dynamics of the victims. This study intended to examine drowning incidents to better understand opportunities for designing appropriate mitigation strategies. We surveyed 43 out of the 83 landing sites in the Frame Survey (Fig 1) from September 4th, 2021, to November 3rd, 2021. Beach Management Units (BMUs), the smallest fisheries’ admin- istrative units, are responsible for registering fishers and keeping written records in the landing sites. Within each county and sub-county, we selected the Beach Management Units (BMUs) reporting the largest number of drowning deaths on the Frame Survey. We sought to capture incidents across a range of BMUs in different sub-counties. We detected duplicate fatal drown- ing incidents in the Frame Survey figures, where BMUs that were geographically close to each other sometimes both counted the same fisher death. We also detected figures that include incidents of fishers who perished over a longer time period outside the study time frame on the Frame Survey (12 months prior to the survey). We targeted incidents linked only to BMUs where reliable reports about the deceased fishers and the circumstances surrounding their deaths were available. Two data tools were designed to collect data: a semi-structured verbal autopsy question- naire and a key informant interview guide. At each BMU, we requested the written record of

any fisher drowning deaths that occurred over a period of twelve months (July 2020 –June 2021; the year preceding the Frame Survey). For each identified death, the verbal autopsy ques- tionnaire was administered to the BMU member who was familiar with the circumstances of the incident. A verbal autopsy is a tool to collect information about probable causes of death in populations lacking adequate civil registration system with medical certification of cause of death [39–41]. Applications of verbal autopsy are not limited to gathering of data on popula- tion cause-of-death structure, but also include exploration of disease outbreaks and risk fac- tors, and investigation of the effectiveness of public health interventions [42–44]. To capture information about fisher drowning death risk factors, our verbal autopsy consisted of four main sections: questions about the person reviewing the incident, characteristics of the deceased (e.g., age, education level, fishing experience), specifics of the incident, and other key PLOS ONE Climate change and small-scale fisher drowning deaths PLOS ONE | https://doi.org/10.1371/journal.pone.0302397 May 22, 2024 4 / 16