Gray Whales Count annual survey of northbound migration in Santa Barbara Channel, California 2011-2012

Keywords: Occurrence, Observation, Occurrence,Land-based,Sightings,annual survey,gray whale migration,marine mammals
Temporal coverage: 2011/2012

Original provider:
Michael H Smith, Gray Whales Count

Dataset credits:
Gray Whales Count

Abstract:
We have defined Gray Whales Count as a research and education project, in which observers (Counters) on land monitor the passage of gray whales (<i>Eschrichtius robustus</i>) migrating northbound through the nearshore of the Santa Barbara Channel, along a corridor extending approximately 3 nautical miles (nm) from shore. Each annual survey is approximately 100 consecutive days from early February though mid-May. (2011 was 105 days; 2012 was 98 days.) Conditions permitting, each survey-day begins at 9 AM and ends usually at 5 PM.

Our survey site is Counter Point on the
Coal Oil Point Reserve in Goleta, California, USA, with GPS coordinates, 34˚24.434'N, 119˚52.701'W. The coastline runs east-west, with northbound whales traveling west, left to right across our Point towards Point Conception. We are able to track across 200 degrees from 80˚ to 280˚ magnetic. Unfortunately, facing east, south, and west, observers also track the sun across the day.

The observation team consists of from one to five Counters, including the Project Coordinator, up to two Supervisors, and up to two Observers. Supervisor shifts are four hours; Observer shifts are two hours; and the Project Coordinator is usually on-site all day. The Project Coordinator and/or a Supervisor is always on Counter Point.

Purpose:
The goals of the research are to estimate the number of gray whales and gray-whale calves migrating northbound through our corridor and to share our data to complement similar sampling-studies along the California coast. Goals of education are to teach the process of scientific research to Counters and to give them the opportunity to conduct a meaningful study, to experience marine mammals in their environment, and to share this process and their enthusiasm with the public through outreach and various media, especially the internet.

Supplemental information:
Sighting locations were calculated using the bearing and distance from the survey site (34˚24.434'N, 119˚52.701'W). Points are the first location sighted, though tracking information was recorded. When calves were sighted, they were included in the total count.
In 2011, we made note of Off-Effort sightings of anything (marine mammals and vessels). In 2012 only Off-Effort sightings of northbound Gray whales were included in the raw data. We do not include Off-Effort data when creating an estimate of the Gray whales in migration. We do keep them in the record of sightings.
It is rare for us to be able to distinguish species for Common dolphins: <i>Delphinus capensis</i> (Long-beaked) or <i>Delphinus delpus</i> (Short-beaked). Occasionally they will come close enough and with the conditions good enough, and we may get an image that will determine species.
Northbound and southbound Gray whales are the same species, but migrating in different directions. Our targets are northbound Gray whales.
There are many California sea lions in our area, in the water close to shore, traveling offshore, resting on buoys, and occasionally on the sand, sick or injured. We do not usually enter sightings of California sea lions, except if they are sick or injured and onshore or they are in exceptionally large groups or involved in a vessel interaction.
This dataset was first published with 2011 data only and was updated with 2012 data later.