Effects of access restrictions and stocking on small water body fisheries in Laos

Abstract

Four different management regimes were identified in small water bodies in Laos: open-access fisheries, both with and without stocking of exotics (mainly Nile tilapia Oreochromis niloticus); community fisheries with restricted access and regular stocking; and fisheries rented out to corporate entities, based on indigenous stocks only. These regimes represent all possible combinations of the two management measures, access (open/restricted) and stocking of exotic species (no/yes) and a test fishing experiment assessed their effects on stock abundance, richness and diversity. The combination of access restrictions and stocking had a strong positive effect on total standing stocks. Stocks of indigenous fish were significantly increased by access restrictions, while stocking of exotics had no effect on indigenous standing stocks. Community fisheries targeted large sizes of exotic species while reducing the exploitation of smaller size groups, which accounted for much of the indigenous stocks. This suggests that stocking can promote active effort regulation and reduce the exploitation of natural stocks. Data on yields and effort were too limited to allow the use of inferential statistics, but indicated that community fisheries were exploited with much lower effort and gave lower yields than open access fisheries, while providing higher returns to fishing effort. This suggests that active management is effective in increasing standing stocks and the efficiency of exploitation, but does not necessarily increase yields unless optimal management regimes can be identified and implemented by the management institutions. No significant effects on wild stock richness or diversity were detected in the test fishing experiment, but wide confidence limits indicated a low statistical power of the test and therefore no definitive conclusions could be drawn. 1998 The Fisheries Society of the British Isles

Production trends, monetary returns and benefit sharing protocols from the extensive aquaculture practice of culture-based fisheries in rural communities in Lao PDR

“…Rural communities in Laos have embraced CBF as a useful activity for augmenting their food fish needs and household incomes, directly and/or indirectly (also see Lorenzen et al, 1998a;Garaway et al, 2006). It is important to note that in the present case, CBF activities have been sustained over five to six cycles, and there is an increasing number of communities adopting CBF to augment their income and wellbeing.…”

A social science perspective on stock enhancement outcomes: Lessons learned from inland fisheries in southern Lao PDR

“…An example of the framework is presented in Fig. 1, and applications to stock enhancement are given by Hartmann (1995); Middendorp et al (1996); Lorenzen and Garaway (1998); Garaway (1999) and Lorenzen et al (2001).…”

“…This includes, the extent to which the technology is taken up (Pushpalatha, 2001) as well as total yields (Hartmann, 1995;Lorenzen et al, 1998;Garaway, 1999;Garaway et al, 2001), recapture rates (Viet et al, 2001) and, as mentioned above, benefits going to different groups of resource users. Unexpected outcomes can occur for a number of reasons.…”

Responsible Approach to Marine Stock Enhancement: An Update

“…While some enhancement initiatives have increased yields, generated economic and social benefits, and helped create better fisheries management institutions, only a few such 'success stories' have been documented in the scientific literature (Pinkerton, 1994;Lorenzen et al, 1998;Drummond, 2004;Uki, 2006;Garaway, 2006;Becker et al, 2008). Overall, the contribution of enhancements to global fisheries production has remained small, at below 2% of the global total (Lorenzen et al, 2001).…”

“…Outcomes of enhancement are determined by interacting, biological, and human dimensions of the fishery system into which they enter and are evaluated against a broad set of criteria. Enhancement 'success stories' often show how positive outcomes are dependent on matching enhancements to fisheries characteristics, transforming governance arrangements, and seeking ways in which enhancement can add value to other management approaches (Pinkerton, 1994;Lorenzen et al, 1998;Drummond, 2004;Uki, 2006;Garaway, 2006;Becker et al, 2008). Conversely, many enhancements have failed not or not only for technical reasons, but because they did not address management issues in the fishery (e.g., sometimes enhancements are developed for lightly exploited stocks or stocks of little fisheries interest), or inadvertently caused problematic responses (such as an increase in fishing effort on already overfished stocks).…”