By By Greta McClain Feb 7, 2013 in Environment Reykjav - Officials in Iceland are blaming the deaths of tens of thousands of herring on low oxygen levels in the Kolgrafafjordur fjord. This is the second time a mass herring death has occurred this winter. On Wednesday, Johann Sigurjonsson, director of the institute, said the number of herring found dead is roughly equal to an entire fishing season worth of herring. He says the large herring population most likely depleted the oxygen in the shallow winter waters of the fjord. Officials believe as spring approaches, the danger to the herring population will decrease as the fish begin to spread out into other areas of the fjord. Robert Örn Stefánsson, biologist and director of the Natural History West, also visited the scene of the mass death. He told We walked about 2.5 km. way to the beach and it's like it was yesterday least there was continuous herring few miles and all this way as we walked. Regions of massive amounts. This was from a nearly continuous distribution up to a thick layer. Where the situation was worst man walked up to the knees in fresh herring. It was a very strong experience as well as sad. The The Icelandic economic minister said he has increased funding for monitoring of the area to see what can be done to prevent future incidents. Sigurjonsson told the We regard this as a serious event. We are investigating; we would like to find out if it is necessary to try to step in somehow. Officials with the Marine Research Institute of Iceland were on scene Monday to investigate the scale of the incident and attempt to determine a cause for the mass deaths. Experts are estimating approximately 25,000 to 30,000 tons of herring have died, similar to the number believed to have died in December due to insufficient oxygen levels.On Wednesday, Johann Sigurjonsson, director of the institute, said the number of herring found dead is roughly equal to an entire fishing season worth of herring. He says the large herring population most likely depleted the oxygen in the shallow winter waters of the fjord. Officials believe as spring approaches, the danger to the herring population will decrease as the fish begin to spread out into other areas of the fjord.Robert Örn Stefánsson, biologist and director of the Natural History West, also visited the scene of the mass death. He told Ruv The Iceland Review reports that school children from nearby Grundarfjörður collected between 25 and 30 tons of the dead herring to sell as animal fodder, worth nearly $2,000. Stefánsson estimated there were an additional 7 tons of fish still on shore. Visserijnieuws reports the the fish death results in a 7.2 million dollar loss in fishing revenue.The Icelandic economic minister said he has increased funding for monitoring of the area to see what can be done to prevent future incidents. Sigurjonsson told the Associated Press More about Herring, Fish, Iceland More news from Herring Fish Iceland