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J.A. Buckel

Publications and source records attributed to J.A. Buckel.

4 recordsLinked to original sources

Prey selectivity and diet of striped bass in Western Albemarle Sound, North Carolina

We collected 1,399 striped bass Morone saxatilis from western Albemarle Sound, North Carolina, during May through October of 2002 and 2003 to characterize diet, prey type selectivity, and prey size selectivity. Herrings Alosa spp., Atlantic menhaden Brevoortia tyrannus, bay anchovy Anchoa mitchilli, silversides Menidia spp., and yellow perch Perca flavescens dominated the diets of age-1 striped bass, while Atlantic menhaden dominated the diets of older striped bass. Selectivity was calculated for three categories of striped bass (ages 1, 2, and 3 + [3-7]) based on fish prey collections from a 61-m beach seine and a 76-m purse seine. Striped bass of all ages primarily consumed fish prey regardless of the month or year. Each age category of striped bass selected for one or more species of prey from the suborder Clupeoidei. Age-1 striped bass selectivity of Alosa spp. generally increased with the progression of each sampling season, whereas selectivity for Atlantic menhaden, Menidia spp., and yellow perch decreased over time within each season. Striped bass of all ages displayed strong selection for Atlantic menhaden and strong selection against spiny-rayed fish prey. Striped bass displayed selection for specific prey, although the mechanisms responsible for selection appear to vary through time and may differ for different prey types. Striped bass either displayed neutral size selectivity or selected for relatively small prey. The mean and maximum sizes of fish prey increased with increases in striped bass size, but the minimum prey size changed little. Our results of seasonal and age-specific changes in selectivity will be valuable for modeling the impact of striped bass predation on resource prey species. ?? Copyright by the American Fisheries Society 2005.

Transactions of the American Fisheries Society

A combined telemetry - tag return approach to estimate fishing and natural mortality rates of an estuarine fish

A joint analysis of tag return and telemetry data should improve estimates of mortality rates for exploited fishes; however, the combined approach has thus far only been tested in terrestrial systems. We tagged subadult red drum (Sciaenops ocellatus) with conventional tags and ultrasonic transmitters over 3 years in coastal North Carolina, USA, to test the efficacy of the combined telemetry - tag return approach. There was a strong seasonal pattern to monthly fishing mortality rate (F) estimates from both conventional and telemetry tags; highest F values occurred in fall months and lowest levels occurred during winter. Although monthly F values were similar in pattern and magnitude between conventional tagging and telemetry, information on F in the combined model came primarily from conventional tags. The estimated natural mortality rate (M) in the combined model was low (estimated annual rate ?? standard error: 0.04 ?? 0.04) and was based primarily upon the telemetry approach. Using high-reward tagging, we estimated different tag reporting rates for state agency and university tagging programs. The combined telemetry - tag return approach can be an effective approach for estimating F and M as long as several key assumptions of the model are met.

Canadian Journal of Fisheries and Aquatic Sciences

Variation in movement patterns of red drum (Sciaenops ocellatus) inferred from conventional tagging and ultrasonic telemetry

We used 25 years of conventional tagging data (n=6173 recoveries) and 3 years of ultrasonic telemetry data (n=105 transmitters deployed) to examine movement rates and directional preferences of four age classes of red drum (Sciaenops ocellatus) in estuarine and coastal waters of North Carolina. Movement rates of conventionally tagged red drum were dependent on the age, region, and season of tagging. Age-1 and age-2 red drum tagged along the coast generally moved along the coast, whereas fish tagged in oligohaline waters far from the coast were primarily recovered in coastal regions in fall months. Adult (age-4+) red drum moved from overwintering grounds on the continental shelf through inlets into Pamlico Sound in spring and summer months and departed in fall. Few tagged red drum were recovered in adjacent states (0.6% of all recoveries); however, some adult red drum migrated seasonally from overwintering grounds in coastal North Carolina northward to Virginia in spring, returning in fall. Age-2 transmittertracked red drum displayed seasonal emigration from a small tributary, but upstream and downstream movements within the tributary were correlated with fluctuating salinity regimes and not season. Large-scale conventional tagging and ultrasonic telemetry programs can provide valuable insights into the complex movement patterns of estuarine fish.

North Carolina

Effects of a delayed onset of piscivory on the size of age-0 bluefish

Variation in advection or other physical forces may accelerate or delay arrival of young marine fishes into productive nearshore habitats, thereby affecting the length of the available growing season. The bluefish Pomatomus saltatrix is an oceanic spawner whose juvenile stages, upon entry into estuarine waters, become piscivorous and thereby experience greatly increased growth. Size attained during the growing season may therefore be determined by time of arrival into estuarine habitats. We exposed bluefish recently recruited to an estuary to three diet shift treatments in which test fish were fed adult brine shrimp Artemia sp. for 0 , 10, or 20 d before they were switched to piscine prey. Bluefish that had a delayed onset of piscivory were smaller after 40 d of growth, indicating that they did not fully compensate for prior periods of slow growth. These bluefish did exhibit immediate moderate growth compensation (about 6% over 10 d) resulting from increased consumption rates, but relatively low growth efficiencies prevented full recovery of their growth losses. Low growth efficiencies may have resulted from an induced developmental handicap or an energetic penalty for prolonged feeding on an Artemia diet. The timing of age - 0 bluefish recruitment into estuarine environments can have a lasting influence on size attained during the first growing season.

Transactions of the American Fisheries Society