WHAT QUESTIONS ARE ANSWERED BY FIELD WORK? Fisheries Overview 1 The Fisheries Technician and Data Acquisition

Steps in Conducting a Fisheries Investigation Fisheries Overview 2 Review of relevant literature Assessing the environment to be sampled Sample the biota Sample the catch and harvest Determine how much to sample Determine what to collect Analyze the data & communicate results

Your Responsibilities as a Fisheries Technician Fisheries Overview 3 A sound understanding of how to operate all sampling equipment  Fisheries related  Oceanographic and chemistry related Meticulous data records Morally sound  Avoid misrepresentation and dishonesty  Fudging the data

Fisheries Examinations Fisheries Overview 4 Stock identification Abundance estimates Mortality rates Growth rates Fisheries recruitment

Stock Identification Fisheries Overview 5 Stock - a group of fish that can be treated as a single management unit  A single interbreeding population Population A Population B

Methodology for Stock Identification Fisheries Overview 6 Geographical analysis Spawning area analysis Catch per unit effort analysis Age composition analysis Tag and release Morphological and physiological analysis

Abundance Estimates Fisheries Overview 7 Using a standard gear unit  Catch per unit effort Correlation techniques Mark and recapture Mortality rates # Time Mortality Curve

Growth Rates Fisheries Overview 8 Useful in analyzing a population’s general health Critical in determining management tactics  Examination of ontogeny  Recreational size and bag limits

SEM Micrograph Compound Microscope

Growth Curves Fisheries Overview 10 Fish length Fish age X X X X X XX X X X X

Fisheries Recruitment Fisheries Overview 11 Recruitment - the number of new individuals added into a population  Spawning stock size  Environmental factors  Predation  Competition