In the last trading session, U.S. stocks ended on a weak note due to banking concerns and weak China data. Among the top ETFs, (SPY Quick QuoteSPY - Free Report) lost 1.2% and (DIA Quick QuoteDIA - Free Report) shed 1%, while (QQQ Quick QuoteQQQ - Free Report) moved lower by 1% in the last trading session.

Two more specialized ETFs are worth noting, as both saw trading volume that was far outside of normal. In fact, both these funds experienced volume levels that were more than double their average for the most recent trading session. This could make these ETFs the ones to watch out for in the days ahead to see if this trend of extra interest continues.

(PXE Quick QuotePXE - Free Report) : Volume 4.18 Times Average

This energy ETF was in the spotlight as around 224,000 shares moved hands compared with an average of 55,000 shares a day. We also saw some price movement, as PXE declined 1.9% in the last session.

The move was largely due to a decline in oil price that had a big impact on energy ETFs like the ones we find in this ETF portfolio. PXE has gained 12.7% over the past month and has a Zacks ETF Rank #3 (Hold) with a High risk outlook.

(IYY Quick QuoteIYY - Free Report) : Volume 2.94 Times Average

This large-cap ETF was under the microscope as nearly 115,000 moved hands. This compared with an average trading volume of roughly 41,000 shares and came as IYY shed 1.1% in the last trading session.

The movement can largely be blamed on market decline. IYY has shed 0.6% in a month and has a Zacks ETF Rank #2 (Buy) with a Medium risk outlook.