▁infl ux ▁of ▁Thor ough bre d ▁imports , ▁mostly ▁from ▁England . ▁R ough ly ▁ 3 , 5 0 0 ▁horses ▁were ▁living ▁in ▁Australia ▁by ▁ 1 8 2 0 , ▁and ▁this ▁number ▁had ▁grown ▁to ▁ 1 6 0 , 0 0 0 ▁by ▁ 1 8 5 0 , ▁largely ▁due ▁to ▁natural ▁increase . ▁The ▁long ▁journey ▁by ▁sea ▁from ▁England , ▁Europe , ▁and ▁Asia ▁meant ▁that ▁only ▁the ▁strong est ▁horses ▁surv ived ▁the ▁trip , ▁making ▁for ▁a ▁particularly ▁health y ▁and ▁strong ▁Australian ▁stock , ▁which ▁a ided ▁in ▁their ▁ability ▁to ▁fl our ish . ▁ ▁Origin ▁of ▁fer al ▁her ds ▁ ▁H ors es ▁were ▁likely ▁conf ined ▁primarily ▁to ▁the ▁Sydney ▁region ▁until ▁the ▁early ▁ 1 9 th ▁century , ▁when ▁sett lers ▁first ▁crossed ▁the ▁Blue ▁Mountains ▁and ▁opened ▁expansion ▁in land . ▁H ors es ▁were ▁required ▁for ▁travel , ▁and ▁for ▁cattle ▁and ▁sheep ▁dro ving ▁as ▁the ▁past oral ▁industry ▁grew . ▁The ▁first ▁report ▁of ▁an ▁escaped ▁horse ▁is ▁in ▁ 1 8 0 4 , ▁and ▁by ▁the ▁ 1 8 4 0 s ▁some ▁horses ▁had ▁escaped ▁from ▁settled ▁regions ▁of ▁Australia . ▁It ▁is ▁likely ▁that ▁some ▁escaped ▁because ▁f ences ▁were ▁not ▁properly ▁installed , ▁when ▁f ences ▁existed ▁at ▁all , ▁but ▁it ▁is ▁believed ▁that ▁most ▁Australian ▁horses ▁became ▁fer al ▁because ▁they ▁were ▁released ▁into ▁the ▁wild ▁and ▁left ▁to ▁f end ▁for ▁themselves .