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We used a Beverton–Holt equilibrium yield model to predict the effects of four different length limits (203, 229, 254, and 279 mm) on harvest of black crappies Pomoxis nigromaculatus and white crappies P. annularis in Weiss Lake, Alabama. The current 254‐mm length limit took effect in 1990, and we wanted to assess length limits with more recent data. We documented angler harvest and catch rates before and after the initiation of the size limit. Size structure, growth, and total mortality were estimated for fish collected with trap nets and by electrofishing. Growth was above average compared with other reservoirs in the state with fish reaching 254 mm in about 2.4 years. Estimates of total annual mortality ranged from 51% to 64% and annual exploitation was 33%, but because of uncertainty, a wide range of fishing and natural mortality rates were incorporated into the simulations. Three years after the length limit took effect, angler harvest and catch of crappies increased two–four fold and the size structure of the population was skewed towards smaller fish. However, recruitment indices showed production of strong year‐classes in the 1990s, compared with weak year‐classes in the 1980s, which confounded interpretation of creel and size structure data and the effects of the length limit. Modeling indicated higher harvest in weight would be achieved with a 254‐mm size limit only if conditional natural mortality was less than 35%. Yield benefits were comparable or decreased at higher length limits when conditional natural mortality rates were higher than 35%. We predicted substantially reduced numbers harvested at progressively higher natural mortality rates and increased length limits. The 254‐mm minimum length limit for crappies in Weiss Lake appeared to provide potential benefits to the fishery. Yield (in weight) would increase because conditional natural mortality was probably less than 35%; however, the actual numbers of fish that anglers could keep would be reduced.

Summary Weight–length relationships are presented for 63 fish species sampled with a commercial trawl vessel at depths ranging from 28 to 370 m between February 2005 and April 2006 in Saros Bay, Turkey. Saros Bay was closed to trawl fishery in 2000, thus, most of the demersal fish species sampled were relatively undisturbed.

The stomach contents of juvenile sharpsnout seabream, Diplodus puntazzo, and juvenile two-banded seabream, Diplodus vulgaris, were investigated in order to determine feeding habits and diet overlap among them. Fish were collected from October 2008 to August 2009 using a beach seine net from the Çanakkale coasts of Turkey. A total of 129 juvenile D. puntazzo (ranging from 13 mm to 77 mm total length) and 951 D. vulgaris (ranging from 15 mm to 97 mm total length) were collected during the sampling periods in the study area. The stomach content analyses showed that the diet of both species mainly comprised copepods and amphipods. In addition, algae were found in the stomach contents. No significant differences were found between the feeding habits of juvenile D. vulgaris and D. puntazzo (ANOSIM; global R statistic = -0.0158; P > 0.05). An important overlap in the diet calculated using the Schoener index was recorded as 0.75 for D. puntazzo and D. vulgaris. Consequently, there was a significant diet overlap and competition for available resources among the feeding habits of D. vulgaris and D. puntazzo in juvenile periods.

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