ic opter ▁shooting , ▁and ▁must ering ▁and ▁tra pping . ▁None ▁of ▁the ▁methods ▁provide ▁complete ▁freedom ▁from ▁suffering ▁for ▁the ▁horses , ▁and ▁the ▁cost ▁of ▁each ▁is ▁very ▁high . ▁The ▁costs ▁include ▁those ▁that ▁are ▁economic , ▁such ▁as ▁research , ▁equipment ▁purch ases , ▁and ▁labour ▁exp end it ures , ▁as ▁well ▁as ▁moral ▁concerns ▁over ▁the ▁w elf are ▁of ▁the ▁horses . ▁As ▁a ▁result , ▁more ▁effective ▁and ▁efficient ▁means ▁of ▁control ▁have ▁been ▁called ▁for . ▁ ▁F ert ility ▁control ▁is ▁a ▁non - le th al ▁method ▁of ▁population ▁management ▁that ▁is ▁usually ▁viewed ▁as ▁the ▁most ▁hum ane ▁treatment , ▁and ▁its ▁use ▁is ▁supported ▁by ▁the ▁R SP CA . ▁While ▁it ▁appears ▁as ▁though ▁these ▁treat ments ▁are ▁effective ▁in ▁the ▁bre eding ▁season ▁immediately ▁following ▁injection , ▁the ▁last ing ▁effects ▁are ▁deb ated . ▁Because ▁it ▁is ▁cost ly ▁and ▁difficult ▁to ▁treat ▁animals ▁repeatedly , ▁this ▁method , ▁despite ▁being ▁ideal , ▁is ▁not ▁widely ▁implemented . ▁ ▁Sho oting ▁by ▁trained ▁marks men ▁is ▁considered ▁to ▁be ▁the ▁most ▁practical ▁method ▁of ▁control ▁due ▁to ▁its ▁effect iveness . ▁The ▁NS W ▁Department ▁of ▁Primary ▁Indust ries ▁believe ▁shooting ▁is ▁the ▁preferred ▁method ▁of ▁population ▁control ▁as ▁it ▁does ▁not ▁subject ▁the ▁horses ▁to ▁the ▁str esses ▁of ▁must ering , ▁y arding , ▁and ▁long - distance ▁transport ation , ▁all ▁of ▁which ▁are ▁related ▁to ▁' capt ure ▁and ▁removal ' ▁methods