General Posters/Press/Software/

General Posters

Press Releases

Software and Data

  • R-package for survey design analysis – PC fileUnix file. This package contains all of the functions for stratified random surveys developed for NEFSC by Stephen Smith in 2006 plus functions for post-stratification and domain estimates. Documentation is available using the R help() facility available for all packages once the package is installed
  • Generation of GIS layers for Nantucket and Georges Bank closed areas – GIS Data (zip), Layers (zip), Files (.docx) and ASCII Data. Space delimited ASCII with self explanatory headers. Each station represents the same area, given the domain of the survey (about 29.4 km2.)

Technologies and Techniques

Dameron-Kubiak Dredge: A fundamental challenge in marine benthic ecology and fishery assessment is to quantitatively collect small infaunal (within the sediment) target species that have non-uniform distribution and/or low mean density (number per unit area). Clams are a prime example of such a species. Previously available sampling gear was either grabs or cores that are limited in sample area and thus had high statistical probability of missing target species with low density; or lined dredges capable of covering large areas (integrating density) but with high retention of accompanying sediment and damage to the target species. The lined dredge also presented non-trivial challenges in deployment and retrieval in that a sediment-filled dredge can weigh several tons, thus challenging winches and creating the opportunity for marginal safety conditions for on-deck crew. SCeMFiS industry members designed and fabricated a research dredge with variable bar spacing (ability to change target size of species under examination) and in situ sample washing capability (wash sediment from the sample as it is collected on the sea floor). The dredge design was finalized between March and May 2014, fabricated in May-July 2014, and tested at sea in August 2014. The dredge performance exceeded expectations, providing high sample retention with little sample damage in a very safe and tractable operating environment. The dredge was tested on two fishery target species – surfclams and ocean quahogs – and proved to be comparable in retention efficiency to previously used lined dredges but with greater ease of use and far less retention of sediment. Increased retention also demonstrated heretofore undescribed localized high densities of pre-recruit-to-fishery-size clams – a positive demonstration of sustainable management success. The dredge was named the Dameron-Kubiak dredge after its designer (Captain T. Dameron) and lead fabricator (Mr. Kubiak) The new dredge was employed as a standard selectivity and juvenile survey dredge in the 2015 NEFSC survey and is anticipated to be a primary survey tool indefinitely into the future.


Theses and Dissertations