Intermarket Weekly
The Oil n' Gold website had an interesting commentary about intermarket activity in October. They say there's an inverse correlation between gold stocks and bond market prices. Very probably you will see ETF activity in some very liquid area of trade on the long side and short on illiquid stocks.
Nobody singles out GBN.V specifically, though there is a relentless arbitrage in the price in the absence of buyers of the stock. The money thus raised has to go into a rising trend, such as bonds thus explaining the constant pressure on small cap stocks.

Oil And Gold
To be a little more sure, you can compare the weekly chart of GBN.V with the rises and falls in the TLT since Dec. 2008. Note the similar number of weeks in a bottoming process circled in green:

supersize: http://www.flickr.com/photos/11747277@N07/6321363710/sizes/l/in/photostream/
stockcharts.com
-F6