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Plastic pollution in the marine ecosystem and their sources have been widely investigated, however some parts of the world remain under studied. Herein, we report on plastic pollution in the Namibian marine ecosystem, based on data collected by fisheries observers between 2003 and 2020 during commercial fishing activities. A total of 79 plastic pollution incidents were reported between 2003 and 2020, which consisted of unspecified non-biodegradable objects (55.7%), unspecified plastic items (25.3%), fishing gear (8.9%), plastic bottles (5.0%), plastic gloves (1.3%) and single-use plastic bags (3.8%). We found no significant Pearson correlation between the number of disposal incidents and the fisheries observer coverage (r = 0.3254, df = 14, p = 0.2187). The spatial analysis in the disposal of non-biodegradable objects show a fair distribution along the Namibian coast with more concentrations around latitude 18⁰S, 22⁰S, and 26⁰S. We conclude that fishing vessels are important marine-based sources of plastic pollution, highlighting a continuous need to raise awareness over the fishing industry, in particular seafarers, on plastic use and management. The study expands the plastic pollution knowledge by quantifying incidents of plastic pollution, plastic litter composition, and identifying spatial distribution in the Namibian waters, thus, to the best of our knowledge, represents a baseline for studies on marine plastic pollution in this oceanic region. Identifying sources of marine plastic litter and providing a spatial picture is a step closer to develop and implement specific regulatory tools to combat marine pollution. [ABSTRACT FROM AUTHOR]

• Neoliberal rollbacks contributed to the privatization of the fisheries observer industry. • Private observer provider companies operate with little government oversight. • Fishing quotas enroll scientific data collection in private property regimes. • The socioeconomic impacts of quota monitoring are unevenly distributed. • Fisheries observation is used to fix the failures of capitalism and neoliberal policy. This article examines fisheries observation and monitoring programs as sites for the neoliberalization of science and the expansion of rights-based management. Rights-based management strategies are argued to avert the tragedy of the commons and yield sustainable commercial fisheries. Individual fishing quotas are a popular but contentious rights-based management tool, that is thought to privatize access to fisheries resources. For quotas to be effective, they require constant monitoring and surveillance to ensure compliance. The task of quota monitoring has fallen to fisheries observers––biologists that accompany commercial fishing trips and collect fisheries data. In this paper I draw from work in science and technology studies (STS) and political ecology, bridging scholarship on the neoliberalization of science and nature. Analyzing archival documents and interview data, I examine the history of the U.S. observer program then narrow focus to the U.S. West Coast Groundfish Observer Program as a case study. Through this analysis, I make two central arguments. First, fisheries observation and monitoring programs have undergone a shift to privatization and are thus important, and to-date understudied, sites of neoliberalization in fisheries science and management. Second, fisheries observation and monitoring programs have been restructured to resolve the inherent shortcomings of both capitalism and neoliberal fisheries policy. I highlight the impacts of restructuring on fishermen and the fisheries observation program more broadly, demonstrating that observation and data collection programs reproduce and reinforce neoliberal governance regimes. I conclude by discussing the ontological and epistemological implications of subsuming environmental monitoring and data collection under neoliberal governance. [ABSTRACT FROM AUTHOR]

Sea turtle bycatch has been documented in the large-mesh gillnet fishery that targets flounder in estuarine waters of North Carolina (NC). However, only portions of the fishery operated under Endangered Species Act Incidental Take Permits and had regular observer coverage to determine the occurrence and extent of sea turtle bycatch. From June through November 2009, an Alternative Platform Observer Program (APOP) was initiated in southeastern Carteret County, NC, to document turtle entanglements. Observers covered 1.6% of the total number of large-mesh gillnet trips reported (1.1% of landings) and documented turtle bycatch (n=22) on 36% of the observed trips (12 of 33). Most turtles were recovered alive (n=15), and all interactions occurred in June, July, and August. Bycaught sea turtle species included 12 greens (Chelonia mydas), 5 Kemp’s ridleys (Lepidochelys kempii), and 5 loggerheads (Caretta caretta). Hauls with bycaught turtles in June had a significantly greater mean string length than those without bycatch (P=0.02), but despite the institution of regulations limiting string length, no difference was found in mean string length overall before (June) and after (July-November) regulations went into effect. Documented turtle bycatch in this area supports the need for observer coverage across the entire spatio-temporal scope of the fishery at levels necessary for robust bycatch estimates. Representative observer data across longer time series can inform managers where and when bycatch risks are greatest and help in developing mitigation measures that decrease bycatch risk while reducing negative economic impacts on the fishers. [ABSTRACT FROM AUTHOR]

Abstract: Obtaining a representative estimate of discard mortality for population and ecosystem assessments is very challenging. This can only rarely be done directly by recovering tagged discarded individuals. Instead, semi-quantitative measures of individual fish vitality or physical condition, obtained by onboard observers prior to discarding, can be used. Such vitality measures can be a good indicator of discard mortality, and by virtue of the data collection method, should also reflect the condition of discards throughout the fishery. Furthermore, vitality can be predicted using covariates known to affect discard mortality, allowing for a more general assessment. We argue that a representative mortality rate can be estimated using the product of at least two probabilities: that of belonging to a particular vitality class, conditional on the factors experienced during capture and catch handling; and the probability of surviving the event, conditional on pre-release vitality. Here we estimate mortalities for five fish taxa captured in southern Gulf of St. Lawrence fisheries. The conditional survival probabilities were obtained using survival analysis of data from experiments in which fish were captured using commercial fishing methods and held to assess short-term mortality (2–3 days). The analysis included a mixture model with a fraction of unaffected individuals, which appears appropriate for data from bycatch mortality studies. Based on this study and the mechanistic interpretation of the mixture model, short-term monitoring of discard mortality may be sufficient to characterize longer term impacts in a number of taxa. [Copyright &y& Elsevier]

Using catch data collected by fishery observers from the otter trawl fleet, we describe changes in the winter distribution of cod on the Newfoundland–Labrador Shelf between 1980 and 1992. We determined the relative abundance of cod in three areas of winter aggregation: south-east of Hamilton Bank, south-east of Belle Isle Bank and south-east of Funk Island Bank. The principal finding was that the cod, during their reproductive period, exhibited significant changes in distribution and behaviour, well before the stock showed signs of collapse. There were three indicators of these changes. First, there was a progressive disappearance of fish from the north with time. Most of the biomass was located in the Hamilton Bank area before 1984. By 1989, most of the fish were found at the Belle Isle Bank and south-east of Funk Island Bank locations and by 1991, only to the south (Funk Island Bank). Second, movements of the prespawning/spawning schools became more limited. Compared with the extensive along-shelf migrations, often covering distances of about 100 km, observed in earlier years, the fish schools after 1989 exhibited less movement to the north. Density of fish in the schools was highest in 1990. By 1991, the schools remained nearly stationary around 49°30′N, near the southern end of their distribution. Third, the schools spread over an increasingly greater range of depths. The greatest density of fish as reflected by high catch rates was generally observed no deeper than 600 m between 1980 and 1988. By 1989–1990, substantial catch rates were observed as deep as 1100 m, particularly to the north although catches continued to be considerable at the shallower depths. These changes in distribution and behaviour were generally coincident with the occurrence of anomalously cold ocean temperatures and heavy ice conditions, but no direct link between these changes and the environment was evident. [ABSTRACT FROM PUBLISHER]