SWFSC Marine Mammal Survey, PODS 1993, Cruise 1509
NOAA Southwest Fisheries Science Center (SWFSC)

Dataset credit

Marine Mammal and Turtle Division, Southwest Fisheries Science Center, NMFS, NOAA


Primary contact Tim Gerrodette NOAA Southwest Fisheries Science Center
Data entry Benjamin Best Duke University



This 1993 line-transect survey was designed to make abundance estimates of the northern stock of common dolphin, Delphinus delphis, in the eastern Pacific. This stock of dolphin is taken in the tropical tuna fishery. The index of relative abundance for this stock, computed from sightings on tuna vessels, has declined substantially in the last decade. However, because tuna vessels cover only the southern portion of the stock's range, the declines in the index may be due to a northward shift in distribution, rather than an actual decline in abundance. The 1993 survey was designed to produce the first range-wide estimates of abundance for the northern common dolphin and its recently described congener, Delphinus capensis. This survey was conducted by the NOAA Southwest Fisheries Science Center aboard NOAA Ships McArthur and David Starr Jordan for a combined total of approximately 32,000 kilometers surveyed from late July to early November 1993. This dataset provides the time-date and geographical coordinates, by species/stock, of all cetaceans detected during the survey, as well as the daily and intra-daily start and end points of the line-transect survey by the NOAA Ship David Starr Jordan.


The primary objective of the cruise was to survey the area inhabited by the northern stock of common dolphins, and to make an estimate of its absolute abundance in order to assess the impact of the dolphins killed by the United States and international yellowfin tuna purse seine fleet in the eastern tropical Pacific.

Supplemental information

This dataset is supplemental to the following datasets:

SWFSC Marine Mammal Survey, PODS 1992, Cruise 1467

SWFSC Marine Mammal Survey, PODS 1992, Cruise 1468

SWFSC Marine Mammal Survey, PODS 1993, Cruise 1508

SWFSC Marine Mammal Survey, Delphinus 2009, Cruise 1640




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.

Attributes in dataset provided

Attribute (table column)Description
datasetdefinition not provided
linenodefinition not provided
cruisedefinition not provided
datedefinition not provided
timedefinition not provided
sightnodefinition not provided
spcodedefinition not provided
scientificdefinition not provided
commondefinition not provided
tsnSpecies ITIS TSN
latitudedefinition not provided
longitudedefinition not provided
schooldefinition not provided
excludeddefinition not provided
geomdefinition not provided
oidUnique ID number (generated by SEAMAP)
Marine mammals1,039
Sea turtles108
Rays and sharks0
Other species0
Non spatial0
Non species0
Date, Begin1993-07-29
Date, End1993-11-05
Temporal prec.111111
Latitude18.69 - 32.09
Longitude-120.10 - -105.50
Coord. prec.2 decimal digits
Data typeAnimal sighting
EffortYES (ID: 216)
Traveled (km)22,474
Effort hours2,383
Sharing policy CC-BY-NC (Minimum)
Also availalbe from iOBIS
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