Answer if you read the book samurai's tale

What is the central idea in this advice from branch rickey to jackie robinson?  

Ineed ideas for this essay something easy that i can do does anyone have any ideas on what i should write on for this 100 points ! write a procedural essay with media that is 1 ½–2 pages in length. clearly state your topic, and include all steps necessary to complete the procedure. you will submit your prewriting and planning documents along with your essay.

How does the author introduces his idea of fish depletion in the first few pages of world without fish?