Norfolk/VA Beach MINEX Vessel Surveys
HDR Environmental, Operations and Construction, Inc.

Dataset credit

The U.S. Navy Marine Species Monitoring Program

Contacts

RoleNameOrganization 
Primary contact Amy Engelhaupt HDR Inc.
Primary contact Dan Engelhaupt HDR, Inc.
Data entry Ei Fujioka Duke University

Citation

Abstract

A combination of visual line-transect survey, photo-identification (photo-ID), and automated acoustic monitoring methods was used to gather important baseline information on the occurrence, distribution, and density of marine mammals near Naval Station Norfolk (NSN) and adjacent areas. The study area was designed to cover areas where United States Navy activity is substantial, including Chesapeake Bay waters near NSN and Joint Expeditionary Base Little Creek-Fort Story, as well as a Mine Exercise (MINEX) Area (W-50) in the Atlantic Ocean off the coast of Virginia Beach, Virginia. Sixty-one line-transect surveys were completed in two zones (INSHORE and MINEX) between August 2012 and August 2015, with 6,550 kilometers (km) and 349.6 hours completed on-effort. The majority of sightings were of bottlenose dolphins (Tursiops truncatus), although humpback whales (Megaptera novaeangliae), harbor porpoises (Phocoena phocoena), and short-beaked common dolphins (Delphinus delphis) were also sighted in the study area on occasion. In addition, loggerhead sea turtles (Caretta caretta), leatherback sea turtles (Dermochelys coriacea), and a Kemp’s ridley sea turtle (Lepidochelys kempii) were sighted during surveys. Conventional line-transect analysis of bottlenose dolphin sightings showed both spatial and seasonal variation in density and abundance, with greatest density in the INSHORE zone during fall months. Densities in the INSHORE zone were calculated as 3.88 individuals per square kilometer (km2) (abundance[N]=1,203) in fall, 0.63 individuals per km2 (N=195) in winter, 1.00 individuals per km2 (N=311) in spring, and 3.55 individuals per km2 (N=1,101) in summer. Densities in the MINEX zone were calculated as 2.14 individuals per km2 (N=1,277) in fall, 0.06 individuals per km2 (N=37) in winter, 1.53 individuals per km2 (N=913) in spring, and 1.39 individuals per km2 (N=829) in summer. Twenty-seven photo-ID surveys were completed, and a photo-ID catalog was created using photos taken during both dedicated photo-ID and line-transect surveys through May 2014; it contains 878 identified individuals to date. Subsequent photos will continue to be added and analyzed. One hundred ten individuals were re-sighted; however, most re-sightings were less than 4 months and 30 km apart. Additional survey effort and further analysis will be required before any clear movement patterns can be determined. C-POD acoustic data-loggers were initially deployed at four sites throughout the study area to cover areas of high United States Navy activity. Bottlenose dolphins were detected in each deployment location during all deployments from August 2012 to December 2015. Though deployments did not provide consistent coverage in all seasons for all sites due to loss of gear, results from two deployment sites nearest to NSN showed a greater level of occurrence during fall months, and a diel pattern of occurrence with increased detections during nighttime hours for three deployment sites.

Purpose

The HDR Marine Species Monitoring (MSM) Team was tasked to initiate a monitoring project in coastal waters around NSN, JEB-LC, JEB-FS, and the Virginia Beach waterfront, including the VACAPES MINEX W-50 training area. The main objective is to provide quantitative data and information on the seasonal occurrence, distribution, and density of marine mammals. Effort was dedicated to working with local researchers and employing proven marine mammal monitoring and research techniques to accomplish the following:

1. Conduct monthly systematic line-transect surveys to determine distribution of marine mammals in the vicinity of NSN, JEB-LC, JEB-FS, and the MINEX W-50 area.

2. Conduct monthly photo-identification (photo-ID) surveys during summer months to determine the site fidelity and distributional patterns of marine mammals utilizing the areas listed above.

3. Supplement visual surveys by deploying and retrieving four C-POD acoustic recording devices to monitor for dolphin echolocation clicks in specific locations.

Supplemental information

[2019-08-27] New data were appended and some columns with empty values were removed. The dataset name is changed by dropping the time period part.

[2014-11-25] Attributes were reorganized so that they meet provider's data schema and effort data (tracklines) were added.

The project is on-going and more data will be added
periodically.
The sighting coordinates represent the locations of the animals (not the vessel platform) calculated from reticle and bearing.

This dataset includes a subset of the data collection for the Norfolk-VABeach Vessel surveys.
Other data of the collection are available in the following datasets:
Norfolk/VA Beach Inshore Vessel Surveys Nov 2012- Nov 2013
Norfolk/VA Beach Photo-ID Surveys Aug 2012-Sep 2013

All the US Navy-funded survey datasets are found in the OBIS-SEAMAP US Navy page.

References

Attributes

Overview

Attributes described below represent those in the original dataset provided by the provider.
Only minimum required attributes are visible and downlodable online. Other attributes may be obtained upon provider's permission unless otherwise noted below.

This section explains attributes included in the original dataset. OBIS-SEAMAP restricts the attributes available to the public to date/time, lat/lon and species names/counts only. Should you need other attributes described here, you are encouraged to contact the data provider.

Attributes in dataset provided

Attribute (table column)Description
oidoid for internal use
bearingBearing
bearingabsTrue (not magnetic) bearing to sighting. Calculated from relative bearing and platform bearing. degrees
beaufortscaleBeaufort sea state (0-12)
behaviorInitial behavioral state of the animal or group when first observed. Examples: Travel, Mill, Rest
countcalvesThe number of calves in the sighting
counttotbestThe best estimate of the number of animals in the sighting
counttotmaxThe highest estimate of the number of animals in the sighting
counttotminThe lowest estimate of the number of animals in the sighting
cueThe sighting cue that initially drew the observers attention
depthsoundingDepth as determined in situ via sounding in meters
distsightThe radial distance to the animal
distsightperpThe perpendicular distance to the animal from the trackline
effortstatusThe effort status of the platform. Options: On-effort (systematic), on-effort (focal follow), on-effort (circling), on-effort (random), off-effort (connector lines), off-effort (transiting), off-effort (other)
glareleftThe amount of glare (0-100%) on the left (port) side of the platform. Refers to glare from 0 to 90 degrees, or viewshed for which observer is reponsible (percent).
glarerightThe amount of glare (0-100%) on the right (starboard) side of the platform. Refers to glare from 270-360 degrees, or viewshed for which observer is reponsible (percent).
headingplatmagneticHeading of the observation platform relative to magnetic North in degrees
headingplattrueHeading of the observation platform relative to true North in degrees
latanimalLatitude of animals in decimal degrees
latplatformThe latitude of the platform in decimal degrees
legnumberA unique identifier for the leg associated with the survey
longanimalLongitude of animals in decimal degrees
longplatformThe Longitude of the platform in decimal degrees
observerThe name of the observer who first sighted the animal
observerleftName of the observer on the left (port) side of the platform
observerrightName of the observer on the right (starboard) side of the platform
oceanThe ocean where the survey took place (Pacific, Atlantic, Indian, etc.)
percentcloudcoverCloud cover as represented by a percentage (percent)
photoframesThe photo frames used for the sighting; or total frames taken
photogapherName of the photographer
photosWere photos taken as part of the sighting? (Y/N)
picPilot in command
platformdedIndicates if the survey was a dedicated marine mammal survey, or if data was gathered opportunistically from a platform on a different mission (Y/N)
platformspeedSpeed of the platform at the time of the sighting in knots
platformtypeType of survey platform (e.g., "aerial", "vessel")
rangecomplexThe Range complex (or complexes) associated with the survey (JAX, SOCAL, Cherry Point, etc.)
reactioninitThe type of reaction at the initial time of the sighting relative to the observation platform
recorderName of the person recording data
datetimeDate and time of the sighting at local time zone
datetimeutcDate and Time together in one cell value (UTC)
sightingnotesNotes field to capture information not covered by existing attributes or other information of interest
sightingnumberThe sighting number for the particular survey day
spcsnmcomCommon name of the sighted species. Output should be singular (e.g. bottlenose dolphin)
spcsnmsciScientific name
sp_tsnTaxonomic Serial Number added by OBIS-SEAMAP
surveyidA survey identifier consisting of data collector, range complex, platform, year, month, and day. (Data Collector/Source)_(Range Complex)_(Platform Type or Details)_(Year)(Month)(Day) (eg. SES_SOCAL_Aerial_20120417)
surveypointA waypoint taken along a trackline OR a start/end point for a trackline
swellSwell height in ft
vertangleorreticleReticle or declination angle in degrees
visibilityThe estimated distance at which an animal could potentially be sighted in km
contractContract code
geomGeometry field added by OBIS-SEAMAP
OBIS-SEAMAP ID1072
Seabirds0
Marine mammals91
Sea turtles84
Rays and sharks0
Other species0
Non spatial0
Non species0
Total175
Date, Begin2012-08-08
Date, End2015-08-01
Temporal prec.111111
Latitude36.61 - 36.94
Longitude-75.96 - -75.57
Coord. prec.5 decimal digits
PlatformBoat
Data typeAnimal sighting
EffortYES (ID: 1202)
Traveled (km)4,692
Effort hours238
Contr. throughNavy
Registered2013-12-04
Updated2019-08-29
StatusPublished
Sharing policy CC-BY (All)
Also availalbe from iOBIS
See metadata in static HTML
See metadata in FGDC XML
See download history / statistics
1