Killer whales occurrences in Venezuelan waters 1982-2008

Jaime Bolaños-Jiménez

Reported occurrences of the killer whale (Orcinus orca) off Venezuela are scarce. Eighteen records were opportunistically collected from April 1982 through January 2008. Bottom depth for the sightings was 10-1,500 m (mean = 444 + SD = 405; mode = 400, n = 18). Five records had available associated still photographs or video. Noteworthy was a videotaped attack by two killer whales on a leatherback turtle (Dermochelys coriacea). Group size ranged from 1-5 individuals (mean = 2.67 + SD = 1.57; mode = 1, n = 18). Adult males were present during 67% of reported sightings; females/juveniles were present in 61% (n = 12 and 11, respectively). Pictures of two male killer whales were sent to researchers in Brazil and the Bahamas for comparison purposes. Adult males were present in 92% of reported sightings. Females and juveniles were observed during 67% of reported sightings. 83% of the records were from December through May. There is currently not enough information to speculate on any seasonality to the occurrence of this species in Venezuelan waters.

The purpose of this work was to update information on killer whale occurrences in Venezuelan waters, on the basis of opportunistic sightings and/or pictures provided by non-professional observers.

A few records did not record day or day and month. For these records, month and day fields were filled with 1. A note was added to [remarks] field, which may be released upon the data provider's permission.

Overview

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.
All attributes are included in the downloadable file (CSV or ESRI File Geodatabase) for "Complete Set of Dataset".

Attributes in dataset

Attribute (table column)	Description
row_id	Row ID
obs_date	Sighting date. A few records did not record day part or month and day parts. If this is the case, a note was added to "remarks" field.
location	Location
latitude	Latitude in decimal degrees
longitude	Longitude in decimal degrees
depth	Depth in meters
sp_obs	Species observed (added by OBIS-SEAMAP)
sp_tsn	Taxonomic Serial Number by Integrated Taxonomic Information System
obs_count	Number of animals
male	Number of males in the group
female	Number of females or juveniles in the group
remarks	Remarks
observer	Observer or source
geom	definition not provided
oid	Unique ID number (generated by SEAMAP)