What problems are experienced by fresh water and marine fish in there habitats and how they overcome it

ANSWER:

Problem faced include; habitat loss and degradation, disease outbreak, invasive species, pollution, over‐exploitation/overfishing, climate change etc.

EXPLANATION:

Problem:

Habitat loss and degradation, disease outbreak, invasive species, pollution, over‐exploitation/overfishing, and climate change are notable problems experienced by freshwater and marine fishes.

Solution:

Anthropogenic activities and stressors that rapidly threaten freshwater and marine fishes are curbed through legislation and other means to prevent extinction of fishes.

Through conservation programs that plans for individual species to more species of entire faunas of a particular location also boost population size and prevent hunting of threatened or endangered species in both realms.

Overtime, genetically modified fishes which can develop resistance to diseases are introduced to the realm.

Moreso, waste channels through which pollutants gets into the water bodies are well-treated for safety of fishes.

your answer is "the 1950's"