If you didn’t know better you would think that all of the CEF preferreds where on a trading halt.
Obviously everyone holding them is plenty happy to just hold on as volume heading toward mid-day are a tiny fraction of the normal volumes (at least per Google Finance which is sometimes lacking in accuracy).
Here is the list right now of the Gabelli issues (not including Ellsworth and Bancroft which are also Gabelli issues).
The 3rd column from the right shows the percentage of average daily volume.
Just as I look at this I note GRX-B has taken a 85 cent fall with a bit more volume–but it is now callable.
The entire list of volumes on preferreds is here.