Calculate CPUE

Calculate CPUE for the situations below. Choose a scale of effort that “makes sense” (and is neither too small nor too big). Show your work.

  1. Suppose that 67 Channel Catfish (Ictalurus punctatus) were caught in seven hoop nets set for only one night (each).
  2. Suppose that 337 Cisco (Coregonus artedi) were caught in 650 m of gillnet set for two nights.
  3. Suppose that 146 age-1 Yellow Perch (Perca flavescens) were caught in three trawl tows that lasted 7, 6, and 6 minutes, respectively.

 

Problems with CPUE Data

Read “Problems with cpue data” section in Maunder et al. (2006) and answer the questions below.

  1. Describe the conceptual relationship between CPUE and N? Define all symbols if you show the equation.
  2. Describe four things that cause q to change over time in a commercial fishery. [Don’t just list these items, provide a description.]