Energy-Efficient Multichannel MAC Protocol Design for Bursty Data Traffic in Underwater Sensor Networks How to reduce power consumption is a critical issue in underwater sensor networks (UWSNs) since sensor nodes have limited energy resource. Utilizing multiple channels and duty cycling may help conserve energy because transmission collisions and idle listening can be reduced. Bursty traffic is common in UWSN; however, we do not find satisfactory solutions that can deliver this type of traffic efficiently in a duty-cycled environment. In this paper, we propose a dynamic duty-cycled multiple-rendezvous multichannel medium access control (DMM-MAC) protocol that is suitable for transmitting bursty traffic in a duty-cycled UWSN. Built on top of multiple-rendezvous multichannel MAC (MM-MAC), a node running DMM-MAC needs only one modem. DMM-MAC can operate in a more realistic multihop environment, instead of a simplified single-hop network, without the information of relative distances or propagation delays to other nodes. Utilizing the proposed dynamic duty cycling mechanism, nodes running DMM-MAC can deliver bursty traffic efficiently. Simulation results verify that DMM-MAC conserves energy and enhances network performance when compared to MM-MAC.