fisher uwe krÜger blames the birds. he says they're taking all the fish.archers at the thÜnen institue in rostock suspect a lack of oxygen. they set up a research area in the baltic. they wanted to find out how much oxygen there is in the water and how high the temperatures rise. a few months later, they had the data they needed. program director christopher zimmermann says the results are devastating. >> from june we were under the critical concentrations and from august, there just wasn't any oxygen there. that might be an error, but you can see that the oxygen concentration is getting lower and lower. the start of august, it is at zero, and that doesn't change. >> massive summer algal blooms are the problem. when the algae die, they drop to the seabed and are broken down by oxygen-consuming bacteria. this creates zones that can no longer support life, called dead zones. >> cod are being sandwiched between high temperatures near the surface and oxygen depletion down below. by august there's no space left. the upper water is too warm and the deeper water

fisher uwe krÜger blames the birds. he says they're taking all the fish.archers at the thÜnen institue in rostock suspect a lack of oxygen. they set up a research area in the baltic. they wanted to find out how much oxygen there is in the water and how high the temperatures rise. a few months later, they had the data they needed. program director christopher zimmermann says the results are devastating. >> from june we were under the critical concentrations and from august, there just wasn't any oxygen there. that might be an error, but you can see that the oxygen concentration is getting lower and lower. the start of august, it is at zero, and that doesn't change. >> massive summer algal blooms are the problem. when the algae die, they drop to the seabed and are broken down by oxygen-consuming bacteria. this creates zones that can no longer support life, called dead zones. >> cod are being sandwiched between high temperatures near the surface and oxygen depletion down below. by august there's no space left. the upper water is too warm and the deeper water