Animal migrations

Abstract

Migracije životinja su kretanja pojedinih životinja na relativno velike udaljenosti, obično na sezonskoj osnovi. Migracija je pojava koju dijele gotovo sve vrste životinja, ribe, sisavci, ptice, pa i ljudi. Teško je pronaći neku životinjsku vrstu koja to ne čini, pa čak i u nekim razvojnim stadijima dok još ne dosegnu razinu odrasle jedinke. Životinje putuju u sve krajeve svijeta kako bi pronašle hranu ili pogodnije klimatske uvjete za svoj opstanak. Ovaj primarni instinkt za preživljavanjem i produljenjem vrste tjera ih na teške i veoma dugačke putove. Jedini razlog za migracije je taj što prednosti udaljenog putovanja višestruko nadmašuju uloženi trud i gubitke koji se dogode na putovanju. Ptice su jedna od tri skupine životinja koja je razvila sposobnost aktivnog leta. Ptice su poznate po svojim dnevnim, godišnjim ili sezonskim migracijama. U radu su opisane anatomske i fiziološke prilagodbe ptica na let te prilagodbe ponašanja za vrijeme migracija.Animal migration is the movement of individual animals over relatively long distances, usually on a seasonal basis. Migration is a phenomenon shared by virtually all species of animals, fish, mammals, birds, and even humans. It is difficult to find an animal species that does not do it, even in some developmental stages, until it reaches the adulthood. Animals all over the world travel to find food or better climactic conditions for their survival. This primary instinct for survival and prolongation of the species is what drives them to difficult and very long journeys. The only reason for migration is that the benefits of distance travel are many times greater than the efforts and losses that occur on the journey. Birds are one of three groups of animals that have developed the ability of an active flight. Birds are known for their daily, annually or seasonal migrations. The paper describes anatomical and physiological adaptations of bird’s flight and behavioural adaptation during migrations