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Distribution Mapping and Analysis Portal

The NOAA Fisheries Distribution Mapping and Analysis Portal (DisMAP) provides easy access to information to track and understand distributions of marine species in the U.S. Marine Ecosystems. Launch the portal to explore, visualize and interact with information on marine species distributions.

Launch Portal

What’s in the Portal?

DisMAP provides access to distribution information for more than 800 marine species caught in NOAA Fisheries bottom trawl surveys in five regions in the United States (Northeast, Southeast, Gulf of Mexico, West Coast, and Alaska). In this first version of the portal all species distribution products are derived from NOAA Fisheries regional bottom trawl survey data. They do not take into account alternative sources of fisheries data such as long-line, plankton, video, or fishery-dependent surveys. Because of this, distribution products are not available for the Pacific Islands or Caribbean regions at this time as those regions do not have bottom-trawl surveys; however incorporating these additional data sources is an area of interest for future releases.

The portal provides information on three key indicators used to track and explore shifts in species distributions:

  • Distribution of biomass in space and time (i.e., distribution surface)
  • Center of biomass
  • Range limits

The distribution surface provides information on how much of the species is expected to be present at any given location within a particular area of interest. This surface forms the basis for the calculation of the other two indicators. The center of biomass (centroid or center of gravity) is a common way to represent the central location (latitude, longitude, or depth) of a population. It is calculated as the biomass-weighted average location (latitude, longitude, or depth) of the population. Tracking this indicator through time provides information on the direction (north vs. south, deeper vs. shallower) in which the population is moving. Tracking changes in range limits is also a useful indicator of species distribution shifts. Range limits are the edges of a species distribution; for instance, the northern most and southernmost latitudes at which the species is found. Changes in range limits, particularly the difference between the northern and southern range limits, can indicate if a population is undergoing range expansions (increasing distance between range limits) or contractions (decreasing distance between range limits).

Explore the Modules

Single species distributions Icon

Single species distributions

Explore visual and numerical representation of several key metrics that define a species range and distribution of individual species over time.

Multispecies Overlap & Interactions Icon

Multispecies Overlap & Interactions:

Under development

Species Shifts & Human Interactions Icon

Species Shifts & Human Interactions

Under development

Regional Summaries Icon

Regional Summaries

Explore how communities have changed at the regional level (e.g. species richness) over time

Data Download Icon

Data Download

Under Development

Disclaimer & Citation

The information provided by DisMAP is intended for information purposes only. The DisMAP managers and developers are not liable for errors in the data. While every effort has been made to ensure the quality of the contributed data, DisMAP cannot guarantee the accuracy of the products and is not responsible for any adverse result based on use of the information or data presented.

NOAA Fisheries. . DisMAP data records. Retrieved from . Accessed .