Filters: Tags: fisheries (X)1,683 results (99ms)
Reliable detection of nonnative alleles is crucial for the conservation of sensitive native fish populations at risk of introgression. Typically, nonnative alleles in a population are detected through the analysis of genetic markers in a sample of individuals. Here we show that common assumptions associated with such analyses yield substantial overestimates of the likelihood of detecting nonnative alleles. We present a revised equation to estimate the likelihood of detecting nonnative alleles in a population with a given level of admixture. The new equation incorporates the effects of the genotypic structure of the sampled population and shows that conventional methods overestimate the likelihood of detection, especially...
No abstract available.
Fluvial geomorphology of the alluvial valley of the Lower Mississippi River reveals a fascinating history. A prominent occupant of the valley was the Ohio River, estimated to have flowed 25,000 years ago over western Tennessee and Mississippi to join the Mississippi River north of Baton Rouge, Louisiana, 750–800 km south of the present confluence. Over time, shifts in the Mississippi and Ohio rivers toward their contemporary positions have left a legacy of abandoned paleochannels supportive of unique fish assemblages. Relative to channels abandoned in the last 500 years, paleochannels exhibit harsher environmental conditions characteristic of hypereutrophic lakes and support tolerant fish assemblages. Considering...
A refined electrofishing technique for collecting Silver Carp: Implications for management. Supporting data
The table provides all fish collected using two different electrofishing methods at Illinois River sites in 2012 and 2013. Length and weights were taken on most species and gender was taken from Silver Carp. Fishes were categorized whether they were netters (caught by nets) or jumpers (jumped in the boat while sampling) and only netters were used in analyses. Large numbers of shad were collected in 2013 and an additional spreadsheet includes abundance data in an aggregated form for those sites. The data is not sensitive/classified and there are no legal restrictions on who may obtain or use the data.
This part of DS 781 presents data for 2-m and 5-m bathymetry and shaded-relief maps of Offshore of Monterey map area, California. The raster data file is included in "BathymetryHS_2m_OffshoreMonterey.zip," which is accessible from http://dx.doi.org/10.3133/ofr20161110. The 2-m and 5-m bathymetry and shaded-relief maps of Offshore of Monterey map area, California, was generated from acoustic bathymetry data collected by California State University, Monterey Bay (CSUMB) and by Monterey Bay Aquarium Research Institute (MBARI), as well as from bathymetric lidar data collected by the U.S. Army Corps of Engineers, Joint Airborne Lidar Bathymetry Center of Expertise (JALBTCX). Acoustic mapping was completed between 1998...
FISHERY MANAGEMENT PLAN FOR THE DOLPHIN AND WAHOO FISHERY OF THE ATLANTIC, CARIBBEAN, AND GULF OF MEXICO.
Robustness of supercritical fluid extraction (SFE) in environmental studies: analysis of chlorinated pollutants in tissues from the osprey (pandion haliaetus) and several fish species
North America's crayfish fauna is diverse, ecologically important, and highly threatened. Unfortunately, up-to-date information is scarce, hindering conservation and management efforts. In Pennsylvania and nearby states, recent efforts allowed us to determine the conservation status of several native crayfishes and develop management strategies for those species. Due to rarity and proximity to urban centers and introduced (exotic) crayfishes, Cambarus (Puncticambarus) sp., an undescribed member of the Cambarus acuminatus complex, is critically imperiled in Pennsylvania and possibly range-wide. Orconectes limosus is more widespread; however, recent population losses have been substantial, especially in Pennsylvania...
At-sea distribution of shy albatrosses Diomedea cauta cauta derived from records of band recoveries and colour-marked birds
Harmonizing the International Undertaking on Plant Genetic Resources for Food and Agriculture with the Convention on Biological Diversity