The population is decreasing since the human population is increasing dramatically. As the human population increases, the demand for fish and seafood also increases since humans eat seafood and fish. As the demand for fish increases, fishermen fish for these snappers more often and in bigger loads. Snappers cant reproduce faster than these fishermen are hunting for them and so the population decreases
If you're a carrier, you're a heterozygote...So let's say S is normal allele and s is diseased allele, then you'd be Ss. Someone with sickle cell anemia would be ss (homozygous recessive)
