Perplexed is a good word to describe the feeling around the whale house these days. It is mid-September and right whale numbers are still unusually low. Below is an e-mail
Amy Knowlton sent to the NEAq team last week that expresses our frustrations but also suggests possible reasons for the low numbers we are seeing in the Bay this year.
Hi all,
I just checked the database for RW defecation - this August is the only August on record (except for 1984-1993 when perhaps we weren't so careful at documenting this?) that there have been no defecations witnessed in BOF, much less many right whales at all! But it does make one wonder what is up. For those of you not here, we did get out yesterday (Sept 9)
and found 3 RW's and 2 sperm whales. One of the RW's (adult male EG#1227) was upcalling and then headpushing and gunshotting (
click to hear incredible audio of right whale sound production)
. Thorny, another adult male EG#1032, seemed to be approaching EG#1227 though they never joined up. The third whale was found around N44 31.0 and W66 32.0 and was booking southwest at a good clip and impossible to work.
Is it sperm whales or lack of food or both? Erghh
A.
Several theories have been suggested to explain the low number of whales in the Bay this year. We've discussed in previous blog entries that
sperm whale 'clicks' may be driving right whales out of the Bay. Secondly, food resources (copepods) may be limited or even dispersed from the deep water basins which typically aggregate copepods in dense concentrations making feeding more efficient. The lack of observed right whale defecations may suggest insufficient food consumption however it is highly speculative given the overall low frequency of right whale sightings.
NEAq team members discuss surveying different right whale habitats outside of the BOF.
We were able to survey this past Monday (Sept 13) but only came across two whales (M/C - EG#3360 and 2010CalfOf3360) and they were also heading southwest out of the Bay. At a team meeting yesterday we discussed moving our survey efforts to areas outside of the Bay where there have been reliable right whale sightings this year. A considerable amount of planning, preparation and cooperative weather is necessary to do this but it will be worth it if we're able to find any sort of right whale aggregations.
We'll update asap of any shift in our survey efforts. It should be quite an adventure.
Zach
i hope that u will find out why there are less right whales in the bay.
ReplyDeletedo you know why the right whales don't like the sound of the sperm whales
ReplyDelete