The nets are indiscriminate about what they catch. They entangle a wide variety of species, including mammals, birds, turtles, and undesired juvenile fish. The nets are not only expending the fish species but also other sea dwellers. Over 1,000 sea lions were killed in 1988 because of being caught in drift nets. The value of the catch is greatly reduced by the use of these nets.
Conventional methods bring a lot more value to the fish.
The nets are left for days, leaving the entangled fish to die and decay. When they are finally removed from the ocean they are found scaleless, eyeless, and sometimes in a mushy state. This makes their price at market greatly decrease. The imperishable net is make of nylon and does not circum to the effects of weathering. This is a problem for sea life that gets caught up in discarded web-like nets.