id ▁terrain ▁gradually ▁s lop es ▁down ▁to ▁the ▁Moz amb ique ▁Channel ▁and ▁mang ro ve ▁sw amps ▁along ▁the ▁coast . ▁ ▁Mad agas car ' s ▁highest ▁pe aks ▁rise ▁from ▁three ▁prominent ▁high land ▁mass ifs : ▁Mar om ok ot ro ▁ ▁in ▁the ▁Ts ar atan ana ▁Mass if ▁is ▁the ▁island ' s ▁highest ▁point , ▁followed ▁by ▁Bob y ▁Pe ak ▁ ▁in ▁the ▁And ring it ra ▁Mass if , ▁and ▁Ts ia f aj av ona ▁ ▁in ▁the ▁An kar atra ▁Mass if . ▁To ▁the ▁east , ▁the ▁Canal ▁des ▁P ang al anes ▁is ▁a ▁chain ▁of ▁man - made ▁and ▁natural ▁la kes ▁connected ▁by ▁can als ▁built ▁by ▁the ▁French ▁just ▁in land ▁from ▁the ▁east ▁coast ▁and ▁running ▁parallel ▁to ▁it ▁for ▁some ▁. ▁ ▁The ▁western ▁and ▁southern ▁sides , ▁which ▁lie ▁in ▁the ▁rain ▁shadow ▁of ▁the ▁central ▁high lands , ▁are ▁home ▁to ▁dry ▁decid uous ▁for ests , ▁sp iny ▁for ests , ▁and ▁desert s ▁and ▁x er ic ▁shr ub lands . ▁Due ▁to ▁their ▁lower ▁population ▁dens ities , ▁Mad agas car ' s ▁dry ▁decid uous ▁for ests ▁have ▁been ▁better ▁preserved ▁than ▁the ▁eastern ▁rain ▁for ests ▁or ▁the ▁original ▁wood lands ▁of ▁the ▁central ▁plate au . ▁The ▁western ▁coast ▁features ▁many ▁protected ▁har b ors , ▁but ▁sil ting ▁is ▁a ▁major ▁problem ▁caused ▁by ▁sed iment ▁from ▁the ▁high ▁levels ▁of ▁in land ▁er os