Research on blue whales near shipping lanes off California after spate of deaths.

08/09/2008 09:10:32 September 2008. At least five blue whales were killed in the autumn of 2007, probably as a result of ship strikes in the southern California area. Three of these animals were discovered in the vicinity of the Santa Barbara Channel. This level of mortality was far higher than had been seen previously, and there may well have been additional deaths of animals that did not wash up; if so, these deaths could be significant to this endangered species.

Cascadia Research, in collaboration with Scripps Institution of Oceanography and with the support of the Channel Islands National Marine Sanctuary and National Marine Fisheries Service, initiated research in 2008 on some of the factors possibly responsible for this mortality.

In August 2008 they began conducting small-boat surveys examining blue whale distribution and behaviour in and around the shipping lanes in the Santa Barbara Channel. They have been able to gather extensive information on the behaviour and movements of whales in the shipping lanes through 7 deployments of two types of suction-cup tags (two dual deployments of both types of tags), all on whales in and near the shipping lanes.

The two tags were the Bprobe acoustic tag and Wildlife Computers Mk10 Fastlock GPS tag. The tags provide an overlapping set of data (depth, temperature, etc.), with the Bprobe providing acoustics and animal body position and orientation and the Mk10 providing for the first time frequent GPS positions of the whale.

Observations and the data from these tags will help address several key objectives:
1. Gather data on the behaviour of blue whales in the shipping lanes including documenting their specific feeding and diving pattern in this area.
2. The GPS tag with over 30 hours on one animal provided detailed movement patterns of the whales present in the shipping lanes in the day and throughout the night (something that could not be done previously). This represents the first successful tag deployments of this Fastlock GPS technology on whales.
3. There were at least three close approaches to whales by ships (less than 1 nautical mile) including one to less than 200m of the tagged whales. Other passages probably occurred and the combination of archived AIS data and the tag data should allow an examination of the evidence of any behavioural reaction.

More about Cascadia research. http://www.cascadiaresearch.org/