DISL-Carmichael-Estes-001-2016
English
DISL Data Management
Data Management Specialist
101 Bienville Boulevard
Dauphin Island
AL
36528
metadata@disl.org
2016-04-22
ISO 19115:2003/19139
1.0
American Horseshoe Crab Abundance in the Northern Central Gulf of Mexico in 2012-2013
2013-08-20
Sightings of American horseshoe crab, Limulus polyphemus, during shoreline surveys conducted in late spring and summer in 2012 and 2013. The study area was in the northern Gulf of Mexico extending from Fort Morgan peninsula of the Alabama coast west to Horn Island off the Mississippi coast, which covers a total distance from east to west of about 60 km. Live crabs, dead crabs, and molts are included.
The purpose of this project was to evaluate suitable habitat for the American horseshoe crab along the Mississippi – Alabama coast and to provide baseline data for the development of a habitat suitability model. The north central Gulf of Mexico barrier islands and shorelines provide habitat for horseshoe crabs. This region has food supply and beach attributes that are known to support some crabs and are consistent with known habitat characteristics elsewhere.
DISL: Carmichael Lab
Ruth Carmichael
Dauphin Island Sea Lab
251-861-2141 x7555
101 Bienville Boulevard
Dauphin Island
Alabama
36528
rcarmichael@disl.org
Maury Estes
University of Alabama in Huntsville
256-961-7735
320 Sparkman Drive
Huntsville
Alabama
35805
maury.estes@nsstc.uah.edu
Fig1_studyarea_manuscript2.png
Study area including locations of barrier islands, Mobile and Mississippi river watershed discharges. Location of the four survey site transects for horseshoe crab surveys (red stars with each star representing a transect).
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American horseshoe crab
Limulus polyphemus
abundance
presence absence
shoreline survey
Dauphin Island Sea Lab
DISL
Dauphin Island
Fort Morgan Peninsula
Petit Bois Island
Horn Island
Alabama
Mississippi
north central Gulf of Mexico
Acknowledgment of the Dauphin Island Sea Lab (DISL) and Alabama A&M University is required in products developed from these data, and such acknowledgment as is standard for citation and legal practices for data source is expected by users of these data. Users should be aware that comparison with other data sets for the same area from other time periods may be inaccurate due to inconsistencies resulting from changes in mapping conventions, data collection, and computer processes over time. The distributor shall not be liable for improper or incorrect use of these data, based on the description of appropriate/inappropriate uses described in the metadata document. These data are not legal documents and are not to be used as such.
English
biota
inlandWaters
oceans
2012-05-21
2013-08-20
-88.75416
-87.96343
30.2
30.25214
true
HSC Data Collection Template - GOM - me - RHC
American Horseshoe Crab Abundance in the Northern Central Gulf of Mexico in 2012-2013 - Feature Catalogue
2016-04-22
Baseline data were collected for numbers of live horseshoe crabs, molts and carcasses. Field surveys were conducted from May to August at two-week intervals in 2012 and monthly intervals in 2013 to coincide with full and new moon phases. Surveys were conducted during the daytime with +/- two hours of high tide. No nighttime surveys were performed due to safety and related boat and volunteer logistics. Four sites with three 2 km transects each were surveyed, including a 2 km control transect on the seaward site of each site. The protocol for field surveys was to walk the water line and search for live crabs, carcasses and molts on the beach area and/or in the water as far as visibility allowed form the water line (~5 m). Each specimen found was classified as live, molt or carcass, the general location of land or water noted, and GPS coordinates noted. All molts and carcasses found were marked with paint and discarded in the dunes or marsh areas off the primary beach to avoid double counting. Live animals were released moving away from the direction of the survey to avoid double counting during the same survey, and sparse numbers of live animals made it easy to avoid double counting.