February 15, 2017

Dock fouling creatures disappearing in SF Bay as salinity hits new lows

Note to iNat dock-foulers: Due to heavy rains, salinity in the SF Bay is presently at record lows, the lowest numbers since 1986 (I think).

Today I was in Redwood City, where salinity has dropped to just 13 psu (Practical Salinity Units). For comparison, the SF Bay is normally around 20-25 psu during the winter, and the coastal ocean is around 33 psu. At the Marine Science Institute (Redwood City) dock, there was almost none of the normal 'mobile life' (mollusks, polychaetes, crustaceans, fish) -- these were the only three species for an hour of looking. The sessile creatures (tunicates, hydroids, bivalves) looked awful as well. And of course everything was covered in silty gunk. One MSI staffer mentioned increased numbers of dead leopard sharks washed ashore (and distressed sharks circling aimlessly). For their own aquariums, MSI has temporarily stopped collecting on the outer coast and is attempting to slowly acclimate their existing creatures to lower salinity levels (they normally pump in SF Bay water for their tanks).

If anyone's available to check other "Inside" SF Bay dock-fouling locations, it would be interesting to see what's survived there. Take along a hydrometer if you have one!

It will be interesting to see when/how the SF Bay creatures recover after the storms.

Posted on February 15, 2017 23:05 by anudibranchmom anudibranchmom | 3 comments | Leave a comment

October 07, 2014

No nudibranchs at Berkeley Marina or Emeryville Marina public boat ramps

Both locations were a bust nudibranch-wise today.

Berkeley was warm, possibly too warm near the surface. Lots of green fluffy algaes looked promising but no joy. Some Ulva, but not much. Mainly sponges and tunicates.

Emeryville was very warm as well. The docks may have been scraped recently (I don't know how fast it grows back), but there was a lot of that cloudy/dirty brown algae coating everything.

Posted on October 07, 2014 05:01 by anudibranchmom anudibranchmom | 0 comments | Leave a comment