What is a feral pigeon?
A feral pigeon is the name given to interbreeding groups of stock doves and rock doves. The groups inhabit areas near man, for example town centres or industrial complexes, and are reliant on him for food and shelter. The habits of these birds mean that they are unlikely to move more that 10 miles from their home site and are not seen in areas where man would usually hunt for food. What do we mean when we say surface radiation was as high as 1.4 millisieverts per hour? Radiation dose to man is measured in units called “Sieverts”. This is equivalent to a large dose of radiation and so sub-units are used, these are millisievert (mSv). The units are also used to evaluate the rate at which the dose is delivered, so a dose rate may be measured in millisieverts per hour. This dose rate is high for the general public, whose dose limit is 1 mSv per year. This may be compared to the average natural background for the UK of 2.6 mSv per year. In this case the radiation dose rate detected at the s
