The Global X Uranium ETF (NYSEArca: URA) and the Market Vectors Uranium+Nuclear Enrgy ETF (NYSEArca: NLR), the two largest nuclear energy and uranium ETFs on the market, have seen their share of tough times since the Fukushima nuclear disaster in Japan more than two years ago.

Following that tragedy, even historically cheap uranium prices and news that emerging markets like China, India, the Middle East and Eastern Europe would still continue their nuclear programs did little to help URA and NLR.

The pair surged in July on speculation that victory by Japanese Prime Minister Shinzo Abe’s Liberal Democratic Party in elections that decided control of Japan’s upper house parliament could spark increased nuclear power use in Japan. Those headlines sent shares of USEC (NYSE: USU), URA’s third-largest holding, soaring and lead to rumors of intense short-covering. [Uranium ETF in Epic Stealth Rally]

However, as quickly as NLR and URA soared in July, the gains evaporated. URA is now just 4.8% above its 52-week low. NLR has been better in recent weeks and some are maintaining a bullish view of the nuclear energy sector. [Nuclear ETFs and the Japan Disaster]

“Investor flows in the main exchange traded products (ETPs) that track uranium have held up despite poor performance this year. Investors appear to be playing a long term game. In the short term, governments are selling their uranium supplies thanks to nuclear weapon disarmament leading to a flood of supply acting as a drag on the price. But, when this has passed through the system and more countries embrace nuclear power the price should better reflect that actual scarcity of this commodity,” according to Markit.

The research firm notes the “net asset value (NAV) performance of the largest ETP, the Global X Uranium ETF (URA) has declined almost a fifth. Despite this, it has posted fund inflows of $11.9m, increasing total assets under management (AUM) to $122.5m. Perhaps in recognition of this, short sellers have covered their positions, from the annual high of 1.7% of the total shares on loan in May to just 0.25%, while the share price tracks multi-year lows.”