Adoption and consequences of new light-fishing technology (LEDs) on Lake Tanganyika, East Africa

Abstract

Maintaining sustainable fisheries requires understanding the influence of technological advances on catch efficiency, as technological creep can ultimately contribute to increased efficiency. Fisheries using light sources for attraction could be widely impacted by the shift to light emitting diode (LED) light systems. We studied the transition from kerosene lanterns to LED lamps in Lake Tanganyika, East Africa, examining factors that led to adoption as well as the impact of the new light sources on fish catch and composition. We used a combination of field experiments with catch assessments, fisher surveys, underwater light spectra measurements, and cost assessments to evaluate the impact of switching from kerosene to LED lamps. Overall, we found a very rapid rate of adoption of homemade outdoor LED light systems in Lake Tanganyika. Most of the batteries used to power these lamps were charged from the city power grid, rather than photovoltaic cells, although the potential exists for a reduction in greenhouse gas emissions. The LED light spectra was distinct from the kerosene light and penetrated much deeper into the water column. Regardless of light type, most of the fish caught within the two dominant species were below maturity. Although the LED lamps were associated with a slight increase in catch, environmental factors, particularly distance offshore, were generally more important in determining fish catch size and composition. The main advantages of the LED lamps were the lower operating costs and their robustness in bad weather. Thus, the primary effect of the use of battery-powered LED lighting systems to attract fish in Lake Tanganyika appears to reduce economic costs and increasing efficiency. However, overall the lake’s fishery remains vulnerable to overfishing.

Application of light-emitting diodes (LEDs) fishing lights to improve catch rates of small-scale trammel net fishery in the Yellow Sea, China

“…The high exploitation rates of stocks would affect energy and material flow characteristics of ecosystems and damage ecosystem balance. Previous studies have demonstrated that the lack of regulations on fishing activities and the control of technological advancements could lead to the overexploitation of stocks and damage the service function of ecosystem (Mgana et al, 2019;Ricci et al, 2022). In coastal China, MOA has formulated and organized a series of management and conservation measures for rational exploitation of the commercial species.…”

Local perceptions on the state of the pelagic fisheries and fisheries management in Uvira, Lake Tanganyika, DR Congo

“…They do not attribute changes in catches to an increase in fishing effort, but to outdated gear, and to a switch to less bright lights to attract the fish. Note that recent research however, showed that the new LED lights were more efficient, so should lead to an increase in catch-rates (Mgana et al, 2019). The discrepancy between this finding and the experience of the fishermen merits to be examined.…”

Benefits and Risks of the Technological Creep of LED Light Technologies Applied to the Purse Seine Fishery

“…LED performance in terms of environmental impact, energy consumption rates, and fuel costs is much more advantageous than those of other lamps, thanks to its maximum illumination power combined with minimum energy consumption, long lifespan, high efficiency, better chromatic performance, and reduced environmental impact [ 25 , 26 , 27 ]. Other applications of LED technology have been tested for the fisheries in African lakes with similar results [ 28 , 29 ].…”