9/5/10

#14 Right Whale Numbers Still Low

R/V Nereid on a calm day in the Bay of Fundy

Despite our initial excitement after our survey on August 27 that suggested the right whales had arrived into the Bay of Fundy after a slow start, it appears that this influx of animals was short-lived. After three days of extensive surveys using two boats on August 29, 30, and 31, only ~17 individuals were sighted. Few of these individuals matched the ~18 whales sighted by the Nereid on August 27 yet the area surveyed over those latter days in August certainly included the area surveyed on the 27th. We are perplexed by the low numbers of right whales and what appears to be substantial movement by individuals in and out of the Bay. Last year during the month of August we saw at least 79 individuals not including calves of the year (data is still in progress). This year we have only had 32 individuals (not including calves) so the change is dramatic.

Though we don't know the reason for this reduced number, some ideas have come to mind. First, for the first time ever in our 30 years of surveys here, we appear to have a number of sperm whales sticking around in the Bay - as many as seven individuals were seen on August 29 by our two vessels. Also, whale watch boats in the area have been seeing them throughout the month. When we put our hydrophone in, the sound of clicking sperm whales was quite loud. It could be that right whales do not like this sound (see video below).



Audio clip of Sperm whale clicks recorded by Dr. Susan Parks (Environmental Acoustic Program, Penn State University) and her PhD student Jenny Tennenssen (Ecology Program, Penn State University) while on the R/V Callisto.
*Note - audio was dubbed to the video for visual effect, clicks can only be heard underwater.

Another possibility is that the food resource has not set up well this year and thus, the copepod density is not high enough for the right whales to stick around.

We are hoping that Hurricane Earl which passed through the region on Saturday morning could shift things around and entice the right whales back into the Bay. Once the seas and winds calm down, we will be heading back into the Bay to see who we find.

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