se ki ri , ▁I j aw ▁( or ▁I zon ) ▁and ▁U kw u ani ▁groups ▁in ▁D elta ▁State ; ▁the ▁B ini , ▁Es an , A uch i , Es ako , oral , ig ara ▁and ▁Af en mai ▁in ▁E do ▁State ; ▁and ▁the ▁Y or uba ▁( I la je ) ▁in ▁O nd o ▁State . ▁Their ▁liv elihood s ▁are ▁primarily ▁based ▁on ▁fish ing ▁and ▁far ming . ▁History ▁has ▁it ▁that ▁the ▁Western ▁Niger ▁was ▁controlled ▁by ▁chief s ▁of ▁the ▁four ▁primary ▁eth nic ▁groups ▁the ▁It se ki ri , ▁Is oko , ▁I j aw , ▁and ▁Ur h ob o ▁with ▁whom ▁the ▁British ▁government ▁had ▁to ▁sign ▁separate ▁" T re aties ▁of ▁Prote ction " ▁in ▁their ▁formation ▁of ▁" Pro te ctor ates " ▁that ▁later ▁became ▁southern ▁Niger ia . ▁ ▁Central ▁Niger ▁D elta ▁Central ▁Niger ▁D elta ▁consists ▁of ▁the ▁central ▁section ▁of ▁coast al ▁South - S outh ▁Niger ia ▁which ▁includes ▁Bay els a , ▁R ivers , ▁Ab ia ▁and ▁Im o ▁States . ▁The ▁Central ▁Niger ▁D elta ▁region ▁has ▁the ▁I j aw ▁( including ▁the ▁Nem be - Br ass , ▁Og bia , ▁Kal ab ari ▁people , ▁I ban i ▁of ▁Op ob o ▁& ▁Bon ny , ▁Ab ua , ▁Ok ri ka , ▁Eng en ni ▁and ▁And oni ▁cl ans ), ▁the ▁Og oni ▁People ▁( K h ana