A wind turbine blade includes an upper shell member and a lower shell member defining an internal cavity therebetween. The shell members are joined with a bond paste along bond lines at the leading edge and trailing edge of the blade. A seal member is disposed between the upper and lower shell members at a designed width of the bond line along at least one of the trailing or leading edges. The seal member has a configuration such that excess flowable bond paste is prevented from migrating past the seal member and into the internal cavity upon mating the upper and lower shell members in assembly of the blade.