The use of mosquito nets in fisheries: A global perspective

Abstract

Free or subsidised mosquito net (MN) distribution has been an increasingly important tool in efforts to combat malaria in recent decades throughout the developing world, making great strides towards eradicating this hugely detrimental disease. However, there has been increasing concern in the natural resource management and healthcare communities over alternative use of MNs, particularly in artisanal fisheries where it has been suggested they pose a threat to sustainability of fish stocks. So far, little evidence has been presented as to the global prevalence and characteristics of MN fishing, limiting global management initiatives and incentives for action across disciplines. We conducted a rapid global assessment of mosquito net fishing (MNF) observations from expert witnesses living and/or working in malarial zones using an internet survey. MNF was found to be a broadly pan-tropical activity, particularly prevalent in sub-Saharan Africa. MNF is conducted using a variety of deployment methods and scales including seine nets, scoop/dip nets, set nets and traps. MNF was witnessed in a broad range of marine and freshwater habitats and was seen to exploit a wide range of taxa, with capture of juvenile fish reported in more than half of responses. Perceived drivers of MNF were closely related to poverty, revealing potentially complex and arguably detrimental livelihood and food security implications which we discuss in light of current literature and management paradigms. The key policies likely to influence future impacts of MNF are in health, regarding net distribution, and natural resource management regarding restrictions on use. We outline critical directions for research and highlight the need for a collaborative, interdisciplinary approach to development of both localised and broad-scale policy.

Identifying potential causes of fish declines through local ecological knowledge of fishers in the Ganga River, eastern Bihar, India

“…The overwhelming response-that destructive fishing and excessive harvests of fish were the primary cause of decline for many species-illustrated this well. This perception of mosquito nets has also been encountered in other regions of Africa and Asia (Bush et al, 2017;Short, Gurung, Rowcliffe, Hill, & Milner-Gulland, 2018), but there is no demonstrated link between their use and observed declines in fish abundance and sizes (Bush et al, 2017). Impacts of different levels and types of fishing on small-scale riverine fisheries need to be investigated along with environmental variability (Abbott & Campbell, 2009).…”

Achieving net benefits: A road map for cross-sectoral policy development in response to the unintended use of mosquito nets as fishing gear

“…Aims of the paper The use of mosquito nets as fishing gear (equipment) has caused increasing alarm and grown in global prevalence for at least the past ten years across developing nations, with limited individual and no concerted policy responses from the relevant management sectors. The potential negative impacts of the activity are increasingly recognised to span the domains of public health, food and nutrition security, biodiversity conservation and sustainable development (Short et al, 2018).…”

“…The control of harmful fishing practices is justifiably the remit of national fisheries ministries. Currently, national policies towards MNF largely focus on enforcement of gear bans under mesh-size regulations (or sometimes MNF-specific legislation) which may be harmful to particularly vulnerable groups (Short et al, 2018). Enforcement of fisheries laws in the regions of concern is often severely limited by a lack of capacity and funding.…”

“…Reports of the alternative use of MNs as fishing gear, used to actively target fish in water columns and living on substrates, began to emerge in the early 2000s (Srivastava, Sarkar & Patiyal, 2002;Jiddawi & Öhman, 2002), coinciding with the advent of mass distribution efforts. The practice appears to have increased exponentially ever since and prevalence of MN fishing has recently been posited as far broader and more frequent than previously appreciated at the global level (Short et al, 2018). Although there have been numerous reports of Mosquito Net Fishing (MNF) in the media, little empirical investigation has been conducted, save for a handful of localised case studies; some of which present the issue as negligible in terms of scale and impact on anti-malarial efforts, and others which suggest it is a significant and growing problem particularly in terms of fishery sustainability (McLean et al, 2014;Bush et al, 2016;Eisele, Thwing & Keating, 2011;Minakawa et al, 2008).…”

“…In reality, this is not a 'new' or 'emerging' activity, though evidence shows expansion. Some may have been engaging in the activity for more than a decade, for some it is likely key to bridging seasonal starvation periods (Short et al, 2018;Abbott & Campbell, 2009) and providing the aforementioned critical micronutrients. For others MNF is likely to be an adaptive response to social and environmental change including desertification and political instability or conflict (McLean et al, 2014).…”