Umjikelezo wokuphila omangalisayo wesalmon

Ama-salmon ayizinhlanzi ezidume kakhulu ngokwenza imisebenzi eminingi phakathi nomjikelezo wabo wokuphila okhangayo futhi oyingqayizivele. Cishe wonke umuntu wake wezwa uhambo oludumile lwe-salmon lokukhiqiza kabusha. Yilokhu okwenza le nhlanzi ikhetheke futhi ihluke, ngoba kuyisibonelo sokumelana nokuzimisela izilwane ezingaba nakho ngenxa yemvelo yokuzala nokusinda.

Ngabe ufuna ukwazi imininingwane eminingi nge umjikelezo wempilo salmon namalukuluku akho?

Umlando we-salmon

Ama-salmon angawohlobo lohlobo I-Oncorhynchus nasemndenini wama-salmonid. Ziyizinhlanzi ezingama-anadromous, okusho ukuthi ukuthuthuka endaweni yasolwandle bese uhlala emanzini amasha. Bayakwazi ukuhlala kuzo zombili izinhlobo zokugxila kasawoti. Indawo yayo yokusatshalaliswa isenyakatho yePacific Ocean nezinhlobo ezithile eziseduze neGulf of Mexico.

Usuku lapho u-salmon wokuqala avele khona emhlabeni wethu alukaziwa kahle, kepha kuyaziwa kancane ukuthi bangabakwaqembu le-teleost fish nokuthi lezi zazibusa olwandle ngesikhathi seCretaceous. Lokhu kubuyela emuva esikhathini lapho ama-dinosaurs ahlala khona cishe eminyakeni eyizigidi ezingama-135 edlule. Kusukela lapho, i-salmon ibe nomjikelezo wokuphila okhetheke kakhulu uma kuqhathaniswa nezinye izinhlanzi. Phakathi kohambo olude lweminyaka eyizigidi ezingama-60, zonke izingcingo zisabalale kuyo yonke iplanethi futhi zathola izinqubo ezihluke kakhulu zokuvela komunye nomunye.

Phakathi nale nqubo yokuziphendukela kwemvelo, ama-salmon akhethe ukuhlala emanzini abandayo nomoya-mpilo wasenyakatho. Ososayensi bazamile ukuqonda izizathu eziholela ekutheni i-salmon ibuyele emuva ekuzaleni, abakaze bakwazi ukuthola iziphetho ngakho.

Umjikelezo wempilo we-salmon

Ukuzalwa

AmaSalmon aqanduselwa emaqandeni awo emifuleni yamanzi angenasawoti. Imvamisa, kuba ekwindla lapho insikazi neyeduna bebeka amaqanda emifuleni ukuze awavundise esidlekeni esakhiwe ngohlaka. Ngemuva kwezinyanga ezimbalwa zokufukamela, amaqanda achanyuselwa kanye nefry salmon achamisele. Bahlala amasonto ambalwa egwadule lapho bethola khona amakhono okubhukuda. Lapho kufika intwasahlobo futhi amazinga okushisa enyuka, kuba nomthelela ekuguqukeni kwezimo zemvelo ezithanda ukufunda kwamazinyane, ashiya amatshe futhi aqale impilo yawo yokuzimela.

Kunochwepheshe abaningi abacwaninga umjikelezo wempilo we-salmon futhi, ngaphezu kwakho konke, lesi sigaba sempilo yabo, ngoba kwenziwa umzamo wokuchaza ukuthi isalmon yazi kanjani ukuthi kufanele babuyele emfuleni ongumama bayozala.

ukuphila

Lapho gazinga likhulu futhi lizimele ngokwengeziwe, bayabhukuda begudla umfula baze bathululele olwandle. Lapho belapho, bayabhukuda futhi bazulazule olwandle ngezikhathi eziguquguqukayo ngokuya nge-salmon ngayinye. Ngalesi sikhathi bathola ukudla nendawo yokuhlala. Uma isikhathi sesidlulile futhi njengoba sebekhulile, isalmon izama ukubuyela endaweni abazalelwa kuyo ukuzala nokuzala. Vele, le ndlela ngokusobala impela iyisisekelo. Ake ucabange ukuthi kufanele babhukude babuyele emuva ngale ndlela emfuleni abazalelwe kuwo. Ngokusobala akuwona wonke ama-salmon asinda ukutshela le ndaba. Indlela eya emfuleni kanina igcwele ubunzima nezingozi.

Buyela emfuleni ongumama

Lapho befika emlonyeni womama ongumfula baqala ukukhuphuka ngamaqembu uma amanzi engenasiyaluyalu kakhulu futhi uma kwenzeka emfuleni omkhulu kakhulu ezinye izinhlobo zikwenza zilandelana. Ngesikhathi sokukhuphuka emfuleni kufanele bavike ama-eddies amanzi, amadwala amakhulu, amabhere nezinye izilwane ezidlayo, izihlahla eziphakathi komfula, ukungcoliswa kweziqukathi namapulasitiki, futhi konke lokhu kuphambene nesikhathi samanje. Zonke lezi zithiyo zidala isimo esibi emzimbeni we-salmon ezenza ukubukeka kwazo konakele uma kuqhathaniswa nangesikhathi behlala ezilwandle.

Ukuzala

Lapho sebekwazile ukukhuphuka ngomfula wonke, bafika endaweni lapho bezalwa khona. Yindawo efanayo lapho bazalela khona kanye nawo wonke amadlozi abo. Kule ndawo bayaqhubeka nokuhlala baze bavuthwe ngokocansi futhi bazale. Uma sezilungele ukuya ocansini ukuzala, insikazi iyabhukuda eduze kwezansi nemifula ukwakha isidleke samatshe lapho izobeka khona amaqanda. Ngenkathi insikazi isakha isidleke, owesilisa uxosha amanye amaduna akhangwa insikazi.

Insikazi isebenzisa umsila wayo ukuyizulisa futhi yakhe isidleke esiphakathi kwamasentimitha angama-40 kuya kwangama-50. Kwesinye isikhathi, njengoba amanye amaduna ezama ukungena esidlekeni esakhiwa yinsikazi, insikazi iba nodlame ukuxosha abangena ngaphakathi. Lokhu kwakhiwa kwesidleke kuthatha amahora ambalwa, kusukela Insikazi ikhetha futhi ijoyine amatshe abonakala efaneleke kakhulu ukwakha "imbeleko" lapho kuzobe kuzalwa khona isalmon entsha. Ngaphezu kwalokho, zingakha izidleke ezifika kwezinhlanu ngenkathi zihlola ikhwalithi nokujula kwazo.

Uma sebazakhile izidleke, insikazi ivumela owesilisa ukuba ame eduze kwakhe ukuze, ngasikhathi sinye, insikazi ikhiphe amaqanda nowesilisa isidoda. Ngale ndlela kwenzeka ukukhulelwa. Lapho amanzi ephuma oketshezini oluyisidoda, insikazi ibuka amaqanda ezansi kwesidleke bese igijimela ukuwavala ngenkathi ishikisha umsila wayo njengefeni. Le nhlangano yenziwa ngaphandle kokuthinta noma iliphi itshe futhi kwenzelwa ukudala umsinga ohambisa amaqanda kugwadule ukugwema ukulimala nokuthi avikelwe kahle.

Njengoba isenzo siphela esidlekeni esisodwa, sakha esilandelayo. Kwilinye ngalinye kufakwa phakathi kwamaqanda ayi-500 kuya kwayi-1000. Ngezinsuku ezilandelayo uyazimboza ukuze azivikele aze afe.

Kubaluleke kakhulu ukuthi lesi sigaba sokugcina sihambe kahle ukuze gazinga elisha likhule. Kungakho ukungcoliswa komhlaba nokuguqulwa kwabantu emifuleni kuyizinto ezenza kube nzima kakhulu ukuthi ama-salmon akhiqize. Njengoba kushiwo ngaphambili, ososayensi bafuna izizathu zokuthi kungani i-salmon izalela kuphela emfuleni womama hhayi kwenye indawo. Kuze kube usuku abukho ubufakazi obutholakele ukuthi kungani. Kucatshangwa ukuthi bane-receptors ohlelweni lwemizwa olusebenzisa izimo zemvelo abebehlala kuzo "njengezikhumbuzo" zokubuyela lapho ukuzobeletha izizukulwane ezizayo.