But these species are especially vulnerable to overfishing, since they are long-lived, slow to reach sexual maturity, have long gestation periods and a low fertility rate.
Kuid need liigid on ülepüügi suhtes eriti tundlikud, kuna nad on pika elueaga, saavutavad hilja suguküpsuse, on pika tiinuseaja ja madala sündimuse tasemega.