Social resilience is an essential aspect of sustainability in environmental management, especially in poor resource-dependent communities. To better understand the dynamics of social resilience, we have conducted a primarily qualitative study of communities dependent on hilsa fishing in two coastal villages in southern Bangladesh. This study applies concepts of social-ecological system (SES), social resilience and co-management in outlining our qualitative data and framing its interpretation. Our findings show that while the establishment of hilsa sanctuary areas has enhanced the previously low ecological sustainability of local small-scale fishing, the management of this program has challenged the social resilience of hilsa fishers by creating new inequalities in the distribution of power and privilege, in terms of the ways in which seasonal fishing bans are enforced and compensation for income loss during the ban periods is distributed. Based on our findings, we suggest specific measures for strengthening social resilience at the local level, including building community networks, developing community infrastructures, updating existing rules and regulations, providing alternative means of generating income for fishers during the crisis periods (e.g. natural disasters and fishing ban periods) and more active sharing of responsibility between stakeholders and government for management of the hilsa fishery. These findings are also applicable to understanding the issues beyond rules and regulations that co-management arrangements need to address in order to be successful and to enhancing the function of co-management arrangements in improving social resilience within resource-dependent communities.