Christopher Newport University bottlenose dolphin sightings in Virginia estuaries 2000-2006

Andrew DiMatteo, US Navy

Dataset credit

Kevin Foss, Christopher Newport University;
U.S. Department of the Navy


Primary contact Andrew DiMatteo US Dept. of the Navy Naval Facilities Engineering Command Atlantic
Data entry Connie Kot


DiMatteo, A. 2014. Christopher Newport University bottlenose dolphin sightings in Virginia estuaries 2000-2006. Data downloaded from OBIS-SEAMAP ( on yyyy-mm-dd.


The Elizabeth River is bounded almost totally by industrial, urban, suburban, commercial shipping and military facilities. Tidal in nature, the river has low flow, resulting in heavy contamination loads. The population studied is the Northern Migratory Stock of the US Atlantic coast, appearing in this area from May through November. Standard small boat, focal group follow, passive observation techniques were used, along with photography of individuals. Data on location, group size estimates, activities observed and relevant environmental observations were recorded every five minutes. The dolphins appear as individuals or pairs in April and May, with group size increasing in June to a peak mean of 29 animals sighted per encounter. Group size then decreases in October and November. Probability of encountering dolphins ranges from 0% during the winter and early spring to over 80% in July, tapering off towards fall. Activity patterns show greatest diversity in July and August, with travel constituting the main activity early and late. Despite a peak of births in the area in May-June, there is little mating until July, with the incidence of sexual activity peaking in September.


To better understand the seasonality and behavior of bottlenose dolphins in the lower Chesapeake Bay.

Data were originally collected by Mr. Kevin Foss at Christopher Newport University during field seasons from 2000-2006. Data were subsequently acquired by the U.S. Navy in 2013.

Supplemental information

[2015-03-24] A few records had a wrong animal count of zero. The value is replaced with a blank representing species presence only.

These data are the result of small boat transects with focal group follows, so that sightings were recorded at regular intervals. Therefore, there may be sightings of the same individuals at different times.

Records that originally estimated a range for the number of adults were attributed with the median number to be conservative.

Three records on land were excluded.


Foss, K.M. and J.R. Reed. 2006. Utilization of urbanized estuaries by northern migratory coastal stock of bottlenose dolphins, Tursiops truncatus in Virginia, USA. Poster Presentation.



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

Attributes in dataset

Attribute (table column)Description
oidUnique ID (created by OBIS-SEAMAP)
recidRecord ID (created by OBIS-SEAMAP
encounterEncounter number
sp_obsSpecies observed
sp_tsnSpecies ISTS TSN
obs_dateDate of observation
obs_timeTime of observation
latitudeLatitude of observation
longitudeLongitude of observation
adultsEstimated number of adults
neonatesEstimated number of neonates
obs_countTotal number of animals observed
t1T (Movement code)
slow_tSlow t (Movement code)
mM (Movement code)
socialSocial (Activity code)
ff (Activity code)
fafa (Activity code)
deep_faDeep fa (Activity code)
dddd (Activity code)
cc (Individual actions code)
tsts (Individual actions code)
tptp (Individual actions code)
friskingfrisking (Individual actions code)
bb (Individual actions code)
fbfb (Individual actions code)
njnj (Individual actions code)
watertempWater Temperature (degrees F)
tideTide code
comments1Comments (originally from provider
time_outTime out
notesNotes for when the original estimated number of adults was recorded as a range, and the median was used.
geomGeometry field added by OBIS-SEAMAP
Marine mammals998
Sea turtles0
Rays and sharks0
Other species0
Non spatial0
Non species0
Date, Begin2000-07-10
Date, End2006-07-25
Temporal prec.111110
Latitude36.75 - 36.98
Longitude-76.46 - -76.11
Coord. prec.6 decimal digits
Data typeAnimal sighting
EffortYES (ID: 1075)
Traveled (km)352
Effort hours80
Contr. through
Sharing policy CC-BY-NC (Minimum)
Shared with OBIS
GBIF (via DOI)
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