SIO Southern California HARPs Acoustic Dolphin Detections 2005-2007

These data were analyzed by Melissa Soldevilla. This research project was funded by F. Stone and E. Young through CNO-N45.

High-frequency Acoustic Recording Packages (HARPs) were deployed at six locations in the Southern California Bight between August 2005 and January 2008 to examine diel, seasonal, and annual patterns of occurrence and distribution. Long term spectral averages (LTSAs) were examined by eye for the presence of echolocation click bouts from Risso's dolphins and Pacific white-sided dolphins. Click bouts were identified to species by a trained analyst based on their spectral characteristics (described in Soldevilla et al 2008). Observations represent presence in one-hour time bins (#obs) and are quantified as the number of one-minute time bins with clicks present. Two click types, A and B, were identified for Pacific white-sided dolphins, which show spatial and temporal segregation in occurrence. HARP recording schedules varied across deployments and include continuous recording, 1/2, 1/3, and 1/4 duty cycles in which 5 minutes were recorded followed by 5, 10, and 15 minutes off, respectively. Effort data is also available in one-hour time bins and includes the number of minutes with recording effort per hour.

The goal of this work was to monitor occurrence of acoustically active cetaceans in the Southern California Bight and develop predictive models of habitat. The data presented here are based on echolocation clicks of Risso's dolphins and Pacific white-sided dolphins.

Times are in GMT.

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.
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
oid	OBIS-SEAMAP Dataset ID
obs_date	Date of observation GMT
obs_time	Time of observation GMT (in 1 hour increments)
obs_count	Number of minutes with clicks present
latitude	Instrument Latitude
longitude	Instrument Longitude
mean_depth	Instrument Depth (m)
depth_st_dev	Depth standard deviation (m) (varied across deployments)
sp_tsn	Species ID code
sp_obs	Species observered and call type
site_id	Site ID code