▁depth . ▁ ▁Wh ales ▁and ▁some ▁other ▁large ▁marine ▁animals ▁feed ▁on ▁and ▁follow ▁large ▁aggreg ations ▁of ▁zo op l ank ton ▁for ▁su sten ance . ▁Based ▁on ▁simple ▁tro ph ic ▁structure , ▁this ▁would ▁mean ▁wh ales ▁and ▁other ▁large ▁zo op l ank ton ▁feed ers ▁can ▁be ▁found ▁at ▁higher ▁abund ance ▁around ▁areas ▁of ▁high ▁primary ▁production , ▁potentially ▁making ▁them ▁important ▁exp or ters ▁of ▁carbon ▁to ▁depth ▁through ▁food ▁falls . ▁Bi ological ▁p ump ▁models ▁indicate ▁that ▁a ▁large ▁amount ▁of ▁carbon ▁u pt ake ▁by ▁the ▁deep ▁sea ▁is ▁not ▁supplied ▁by ▁partic ulate ▁organ ic ▁carbon ▁( PO C ) ▁alone , ▁and ▁must ▁come ▁from ▁another ▁source . ▁Later al ▁ad ve ction ▁of ▁carbon , ▁especially ▁in ▁coast al ▁areas ▁cont ributes ▁to ▁this ▁def ic it ▁in ▁the ▁model , ▁but ▁food ▁falls ▁are ▁also ▁another ▁source ▁of ▁organ ic ▁carbon ▁for ▁the ▁deep ▁ocean . ▁Vari ous ▁percent ages ▁of ▁the ▁food ▁fall ▁contribution ▁to ▁the ▁total ▁carbon ▁flux ▁to ▁the ▁deep ▁ocean ▁have ▁been ▁hypoth es ized , ▁r anging ▁from ▁ 0 . 3 % ▁to ▁ 4 %. ▁ ▁There ▁is ▁growing ▁evidence ▁that ▁the ▁contribution ▁of ▁food ▁falls ▁to ▁the ▁deep ▁ocean ▁carbon ▁flux ▁is ▁larger ▁than ▁originally ▁proposed , ▁especially ▁on ▁the ▁local ▁scale ▁in ▁areas ▁of ▁high ▁primary ▁product ivity . ▁Unfortunately , ▁contributions ▁of ▁food ▁falls ▁to ▁the ▁bi ological ▁p ump ▁are ▁hard ▁to ▁measure ▁and ▁rely ▁on