explains the differences between Haiku and Senryu. Kathy Lippard Cobb wrote the information and included samples of each. She states that senryu deals with human nature, satire, humor, and political issues. Debates about what is or is not senryu is confusing. When poets submit a poem that could be haiku or senryu, they often let the editor decide which it is. The two forms are similar structurally but different in tone.
See Cobb’s article for more detail and examples.