Recently, critical projects were developed using wireless sensor network (WSN) such as medical and military projects. Performing reliable communication in WSN is extremely important for such projects. To be able to perform reliable communication, packet loss must be minimal. Packet loss, energy and latency are the most serious problems for transport protocols. In this paper, reliable, energy- and delay-sensitive transport layer protocol (ALORT) has been developed for WSN. The proposed protocol provides optimum reliability, optimum packet latency, minimum energy cost and high packet delivery ratio by changing loss recovery mechanism (LRM) according to channel error rates. ALORT algorithm is compared with PSFQ and DTC in terms of packet delivery ratio, end-to-end latency and energy cost by MIXIM framework in OMNET++. ALORT algorithm reduces energy cost and end-to-end latency and increases packet delivery ratio.