But BDO partner and natural resources specialist Bruce Gordon said the BDO Explorer Quarterly Cash Update showed some bright spots.

"This quarter's update points to a continuation of the tough conditions we've seen over the last year or two for junior explorers," he said.

"The median spend on exploration activity fell 27% from the December 2013 to March 2014 quarters, which is the largest periodic decrease since we started looking at these trends.

"Also concerning is that since the June 2013 quarter, the percentage of companies ceasing exploration expenditure has consistently risen from about 7% to 10%."

Gordon said companies were using the tough times to get themselves into a better financial position by raising capital or reducing costs.

Still, only 58% of companies had enough cash to cover more than two quarters of net operating expenditure, though that was up from 54%.

And 94% of the companies that had two quarters or less of cash in the December quarter still only had two quarters or less of available cash in the March quarter.

"In addition, more than three quarters (76%) of explorers now have cash reserves sufficient to maintain administrative expenditure for more than two quarters, indicating greater financial capacity to operate for an extended period," BDO corporate finance partner Dan Taylor said.

The number of companies with cash to cover only one quarter fell from 27% to 26%, or 220 explorers.

About 40% of junior explorers raised cash in the March quarter, including 123 that managed to raise more than $A1 million.

Gordon said BDO was keeping a close eye on those companies to see if the funds were being used for exploration or "lifestyle purposes".

Leading the raisings was Tigers Realm Coal, which raised $56 million for its Russian projects.

The report looked at 856 mining, oil and gas explorers.