Release techniques for marine fishes

Proper release of marine fishes has become increasingly important to anglers. The use of fisheries management tools such as size limits, bag limits and closed seasons as well as stronger conservation ethics have resulted in more and more fish being released. In order to maintain healthy fish populations, each angler is responsible for fishing legally, carefully handling fish that are hooked and releasing fish that are not harvested so they can spawn or perhaps be caught again. (PDF contains 4 pages.)

A Biogeographic Assessment off North/Central California: To Support the Joint Management Plan Review for Cordell Bank, Gulf of the Farallones, and Monterey Bay National Marine Sanctuaries: Phase I - Marine Fishes, Birds and Mammals.

In the spring of 2001, NOAA’s National Marine Sanctuary Program (NMSP) and National Centers for Coastal Ocean Science (NCCOS), in consultation with the National Marine Fisheries Service (NMFS), launched a 24-month effort to define and assess biogeographic patterns of selected marine species found within and adjacent to the boundaries of three west coast National Marine Sanctuaries. These sanctuaries, Monterey Bay, Gulf of the Farallones, and Cordell Bank are conducting a joint review process to update sanctuary management plans. The management plans for these sanctuaries have not been updated for over ten years and the status of the natural resources and their management issues in and around the sanctuaries may have changed. In addition, significant accomplishments in research and resource assessments have been made within the region. Thus, it is important to incorporate new and expanding knowledge into the revised management plans for these Sanctuaries.

Field Guide to Nonindigenous Marine Fishes of Florida

The purpose of this field guide is to provide information on nonindigenous (i.e., non-native) fishes that have been observed in Florida’s marine waters. Introductions of non-native marine fishes into Florida’s waters could be intentional or unintentional, and are likely from a variety of sources, including aquarium releases, escape from aquaculture, loss due to extreme weather events (e.g., flooding from hurricanes), and possibly transfer with ballast water or hull-fouling. Presently the lionfishes (Pterois volitans and P. miles) are the only non-native marine fish species known to be established along the coast of Florida. All other marine fishes in this guide (except the euryhaline species, see below) have infrequent occurrences, occur singly or in small groups, and have not yet become self-sustaining populations. Aquarium releases are one of the major pathways whereby nonindigenous fishes gain access to new environments (Ruiz et al. 1997; Fuller et al. 1999). Most of the nonindigenous marine fishes found in Florida’s waters are thought to be aquarium fishes that either were illegally released into the ocean or escaped captivity (e.g., during severe storm/flooding events). Indeed, south Florida is a hotspot for nonindigenous marine aquarium fishes (Semmens et al. 2004). Increased public awareness of the problems caused by released or escaped aquarium fishes may aid in stemming the frequency of releases. For example, HabitattitudeTM (www.habitattitude.net) is a national public awareness and partnership campaign that encourages aquarists and water gardeners to prevent the release of unwanted aquarium plants, fish and other animals. It prompts hobbyists to adopt alternative actions when dealing with these aquatic plants and animals. (PDF file contains 133 pages.)

A histopathologic evaluation of gross lesions excised from commercially important North Altantic marine fishes

Histopathologic studies of lesions found in commercially important North Atlantic marine fishes are uncommon. As part of a comprehensive Northeast Fisheries Center program ("Ocean Pulse") to evaluate environmental and resource health on the U.S. Continental Shelf from Cape Hatteras to Nova Scotia, grossly visible lesions of the gills, integument, muscle, and viscera of primarily bottom-dwelling fishes were excised and examined using light microscopy. Several gadid and pleuronectid fishes accounted for most of the lesions observed. Most pathological examinations were incidental to samples taken for age and growth determination and evaluation of predator/prey relationships. Several gadids, with either gill, heart, or spleen lesions, were sampled more intensively. Gill lesions principally affected gadids and were caused by either microsporidans or an unidentified oocyte-like cell. The majority of gastrointestinal lesions consisted of encapsulated or encysted larval worms or microsporidan-induced cysts. Few heart lesions were found. Integumental lesioos included ulcers, lymphocystis, and trematode metacercariae. Liver lesions almost always consisted of encapsulated or encysted larval helminths. Necrotic granulomata were seen in muscle and microsporidan-induced granulomata in spleen. Although not numerous, histologically interesting lesions were noted in integument, heart, liver, spleen, and muscle of several fish species. Histologic study of tissues excised from a variety of demersal and pelagic fishes from the eastern North Atlantic (France, Germany, Spain) revealed assorted integumental, renal, hepatic, and splenic lesions. Small sample size and non-random sampling precluded obtaining a meaningful quantitative estimate of the prevalence of the observed lesions in the population at risk; however, a useful census has been made of the types of lesions present in commercially important marine fishes. (PDF file contains 20 pages.)

Advances in methods for determining fecundity: application of the new methods to some marine fishes

Estimation of individual egg production (realized fecundity) is a key step either to understand the stock and recruit relationship or to carry out fisheries-independent assessment of spawning stock biomass using egg production methods. Many fish are highly fecund and their ovaries may weigh over a kilogram; therefore the work time can be consuming and require large quantities of toxic fixative. Recently it has been shown for Atlantic cod (Gadus morhua) that image analysis can automate fecundity determination using a power equation that links follicles per gram ovary to the mean vitellogenic follicular diameter (the autodiametric method). In this article we demonstrate the precision of the autodiametric method applied to a range of species with different spawning strategies during maturation and spawning. A new method using a solid displacement pipette to remove quantitative fecundity samples (25, 50, 100, and 200 milligram [mg]) is evaluated, as are the underlying assumptions to effectively fix and subsample the ovary. Finally, we demonstrate the interpretation of dispersed formaldehyde-fixed ovarian samples (whole mounts) to assess the presence of atretic and postovulatory follicles to replace labor intensive histology. These results can be used to estimate down regulation (production of atretic follicles) of fecundity during maturation.

Length-weight relationships of commercially important marine fishes and shellfishes of the southern coast of Karnataka, India

The parameters of the length-weight relationship of the form W = aLb are presented for 51 species of commercially important marine fishes and shellfishes caught along the southern coast of Karnataka, India. Samples from commercial (trawl, purse seines, gill nets) and artisanal gears were taken during August 1999 to May 2001. The ‘b’ value ranged between 1.942 and 3.616 with a mean of 2.80, standard deviation of 0.32, and mode of 3.

Diet composition and food habits of demersal and pelagic marine fishes from Terengganu waters, east coast of Peninsular Malaysia

Fish stomachs from 18 demersal and pelagic fishes from the coast of Terengganu in Malaysia were examined. The components of the fishes’ diets varied in number, weight, and their frequency of occurrence. The major food items in the stomachs of each species were determined using an Index of Relative Importance. A conceptual food web structure indicates that fish species in the study area can be classified into three predatory groups: (1) predators on largely planktivorous or pelagic species; (2) predators on largely benthophagous or demersal species; and (3) mixed feeders that consume both pelagic and demersal species.

Length-weight relationships of marine fishes from the central Brazilian coast

Parameters of the length-weight relationship are presented for 85 fish species from the marine and estuarine regions of the central Brazilian coast (latitude 13° to 23° S). Three different methods were used. A non-linear iterative process using the quasi-Newton algorithm yielded a better fit for all data sets analyzed. The length-weight allometry coefficient b estimated from standard length data tended to be lower than from total length data. The difference between these estimates was significant for some species.

Length-weight relationships of Cuban marine fishes

A total of 140 sets of parameters (a and b) of the length-weight relationships (LWR) of the form W=aL super(b) are presented for fishes caught in Cuban waters. These parameters cover 94 species of fish belonging to 43 families. Most of the parameters were compiled from 107 sets of published and unpublished studies. Twenty-five sets of parameters were from personal communications through colleagues in Cuba, while the remaining eight sets were estimated by the authors from unpublished data.

Length-weight relationship of marine fishes from southern Brazil

The relationship between length (L) and weight (W) was estimated for 80 species belonging to 50 families of marine fishes from the shelf and upper slope of southern Brazil (lat. 28°S - 34°S). Sample sizes (n) for different species ranged from 11 to 14 741 specimens collected from commercial landings and research surveys. The fit of the equations (W=aLb) with a and b parameters estimated from regular and functional regression (of log-transformed weight and length data) as well as from a non-linear iterative process using the quasi-Newton algorithm were compared. The non-linear method gave the most accurate estimates in terms of residual sum of squares. Differences were less than 2.3% for n>500 compared with predictive regressions and 1.5% compared with functional regressions. No difference was observed between both predictive and functional regressions. Determination coefficients (r2) increased with sample size, and the highest r2 were obtained for 50fishes.

Vital statistics of marine fishes of Vanuatu

Vital statistics are presented for 38 marine species of Vanuatu based on previous studies conducted in the area, with parameters describing growth (6 species, 13 sets of parameters), mortality (estimates of M for 6 species), length-weight relationship (32 species), and reproduction (length at first maturity for 26 species, months of reproduction for 18 species). The species covered belong mainly to the family Lutjanidae.

Growth parameters of marine fishes in Cuban waters

A total of 73 sets of growth parameters for 34 species belonging to 12 families of marine fish caught in Cuban waters are presented. These parameters are compiled from existing studies (58 sets) or derived from data obtained in the original literature (15 sets).

Comparison of Standard Length, Fork Length, and Total Length for Measuring West Coast Marine Fishes

Measurements of adult marine fishes on the U.S. west coast are usually made using one of three methods: standard length, fork length, or total length. Each method has advantages and disadvantages. In this paper we attempt to determine whether one method is faster and/or more reliable than the other methods. We found that all three methods were comparable. There was no appreciable difference in the time it took to measure fish using the different methods. Fork length had the most reproducible results; however, it had the highest level of bias between researchers. We therefore suggest that selection of measurement type be based on what other researchers have used for the species under study. The best improvement in measurement reliability probably occurs by adequate training of personnel and not type of measurement used.