This paper adapted the modified dynamic deterrence model to investigate factors affecting compliance with mesh size regulation. the reduced form of this model is tested based on data from the Jebel Aulia Reservoir (JAR) in Khartoum State, Sudan. Factors that determine noncompliance with mesh size regulations were analysed, using the Tobit model. The results showed that the main determinants of noncompliance are poverty and weak and inefficient institutions. This has induced a sudden increase in violation that has led to desperate fishery situations. Young fishers are more likely to violate these regulations, and the study finds that deterrence and social variables are both important determinants of noncompliance with mesh-size regulation. A regime of self enforcement to manage this resource is not possible due to various factors, such as low levels of education, lack of proper knowledge about regulations, and the low skills and lack of ability of administration and of the funding needed to implement such a regime. The study therefore suggests a co-management regime given that co-management increases the awareness of fishing communities about the need for sustainable management of fishery resources and in this turn helps to reduce violation. More than half of the surveyed fishers believed that this regime is suitable for them to achieve sustainable fishery resource.