▁M ating ▁pairs ▁often ▁stay ▁int act ▁even ▁though ▁the ▁male ▁and ▁female ▁are ▁apart ▁for ▁long ▁periods ▁of ▁time ▁over ▁the ▁summer ▁during ▁mol ting ▁times . ▁The ▁pair ▁then ▁reun ites ▁at ▁winter ing ▁areas . ▁ ▁In ▁I cel and ▁the ▁bird ▁is ▁known ▁as ▁h ús ö nd ▁( house - du ck ); ▁it ▁is ▁a ▁common ▁species ▁of ▁the ▁Lake ▁M ý vat n ▁in ▁the ▁north ▁of ▁the ▁country . ▁ ▁Be havior ▁They ▁are ▁mig rat ory ▁and ▁most ▁winter ▁in ▁protected ▁coast al ▁waters ▁or ▁open ▁in land ▁waters . ▁Bar row ' s ▁golden ey e , ▁along ▁with ▁many ▁other ▁species ▁of ▁sea ▁du cks , ▁rely ▁on ▁urban ized , ▁coast al ▁est u aries ▁as ▁important ▁places ▁on ▁their ▁migration ▁patterns . ▁These ▁est u aries ▁provide ▁excellent ▁winter ing ▁and ▁stopping ▁places ▁during ▁the ▁du cks ' ▁migration . ▁It ▁is ▁an ▁extremely ▁rare ▁v agrant ▁to ▁western ▁Europe ▁and ▁to ▁southern ▁North ▁America . ▁ ▁These ▁div ing ▁birds ▁for age ▁under water . ▁They ▁eat ▁aqu atic ▁insect s , ▁cr ust ace ans ▁and ▁p ond ▁veget ation . ▁The ▁main ▁st ap les ▁of ▁the ▁bird ' s ▁di et ▁are ▁Gam mar us ▁ocean icus ▁and ▁Cal li op ius ▁la e vi us cul us , ▁which ▁are ▁both ▁marine ▁cr ust ace ans . ▁A ▁large ▁part ▁of ▁their ▁di et ▁consists ▁of ▁muss els ▁and ▁g ast rop ods . ▁