Fish Ecology and Fisheries Chapter 23 Fish Ecology and Fisheries Dodds & Whiles ©2010 Elsevier, Inc.

FIGURE 23.1 A large pike (Esox lucius). (Photograph courtesy of Chris Guy). ©2010 Elsevier, Inc.

FIGURE 23.2 The proportion of total samples containing various numbers of fish species from tropical and temperate streams. The total numbers of samples were 204 in the tropical streams and 815 in the temperate streams. (After Matthews, 1998). ©2010 Elsevier, Inc.

FIGURE 23.3 Number of fish species as a function of distance from headwaters in the Kali Gandaki River, Nepal. Statistical analysis of the data suggests that the number of fish species increases with river distance up to about 300 km. (Data from David Edds). ©2010 Elsevier, Inc.

FIGURE 23.4 Number of piscivorous species as a function of number of prey species from 178 fish assemblages in eastern North America. The dashed line denotes a 1:1 relationship. Note that more predatory than prey species occur in only one case. (After Matthews, 1998). ©2010 Elsevier, Inc.

FIGURE 23.5 Conceptual model of energy requirements for survival, growth, and reproduction as a function of an environmental gradient. If 100% or more of the available energy is required for survival, the fish will not survive. If the sum of energy required for survival and growth exceeds 100%, the fish will not grow, and if the sum of energy for survival, growth, and reproduction is less than 100%, the fish can reproduce. ©2010 Elsevier, Inc.

FIGURE 23.6 Conceptual illustration of fishery types in temperate lakes with summer stratification as a function of temperature and trophic status. ©2010 Elsevier, Inc.

FIGURE 23.7 Growth of channel catfish (Ictalurus punctatus) on four carbohydrate sources as a function of protein content of food. (Data from Simco and Cross, 1966). ©2010 Elsevier, Inc.

FIGURE 23.8 Effect of predator (Oreochromis mariae) on the rate at which a stickleback (Gasterosteus aculeatus) consumes prey (Tubifex). This experiment included an adjacent fish cage that could hold the predator, and worms were placed in tubes at various distances from the adjacent cage. The stickleback had to enter the tube and lose sight of the predator to take a worm. With no predator, the worms were taken from all tubes equally. With the predator, the sticklebacks preferred to feed as far away from the predator as possible. (Modified from Milinski, 1993). ©2010 Elsevier, Inc.

FIGURE 23.9 The number of bluegill (Lepomis macrochirus) at each length and (B) the relationship between length and wet weight for fish taken by electrofishing from Pottawatomie State Fishing Lake, Kansas, on September 29, 1999. ©2010 Elsevier, Inc.

FIGURE 23.10 A fin ray from a river carp sucker (Carpiodes carpio) showing growth rings. (Photograph courtesy of Chris Guy). ©2010 Elsevier, Inc.

FIGURE 23.11 William Ricker. ©2010 Elsevier, Inc.

FIGURE 23.12 Global production of selected freshwater organisms by aquaculture in 1989; note the log scale on the y axis. (Data from Stickney, 1994). ©2010 Elsevier, Inc.