It shall be the duty of each district attorney in this state and county prosecuting attorney in each county to prosecute and defend, for the state, in all courts of the county or counties in his district or county, all causes, criminal or civil, arising under the provisions of this chapter, or any law or regulation for the protection of wild animals, birds or fish, in which the state may be a party or may be interested or concerned. Circuit judges shall give the grand juries, when organized, the provisions of the laws relating to wild animals, birds and fish strictly in charge and shall urge strict inquiry into all violations thereof.