UCamryn Allen, usosayensi ku-National Oceanic and Atmospheric Administration eHawaii, wenza ucwaningo ekuqaleni komsebenzi wakhe wokulandelela ukukhulelwa kumakoala esebenzisa amahomoni. Wabe eseqala ukusebenzisa izindlela ezifanayo ukuze asize abacwaningi akanye nabo banqume ngokushesha ubulili bomfudu wasolwandle.
Ngeke ukwazi ukubona ukuthi ufudu luyini ngokulubuka nje. Ukuze uthole impendulo enembile, i-laparoscopy ivame ukudingeka - ukuhlolwa kwezitho zangaphakathi zofudu kusetshenziswa ikhamera encane efakwe emzimbeni. U-Allen uthole ukuthi anganquma kanjani ubulili bezimfudu esebenzisa amasampula egazi, okwenza kwaba lula kakhulu ukuhlola ubulili benani elikhulu lezimfudu.
Ubulili bofudu oluchanyuselwe eqandeni bunqunywa izinga lokushisa lesihlabathi lapho amaqanda angcwatshwa khona. Futhi njengoba ukushintsha kwesimo sezulu kushayela amazinga okushisa emhlabeni wonke, abacwaningi abazange bamangale ukuthola izimfudu eziningi zasolwandle zesifazane.
Kodwa lapho u-Allen ebona imiphumela yocwaningo lwakhe e-Australia's Rhine Island - indawo enkulu futhi ebaluleke kakhulu yokuzalela izimfudu zasolwandle eziluhlaza ePacific - wabona ukuthi isimo sasibucayi kangakanani. Izinga lokushisa lesihlabathi lapho lenyuka kakhulu kangangokuba inani lezimfudu zezinsikazi laqala ukudlula inani labesilisa ngesilinganiso esingu-116:1.
Amathuba anciphile okusinda
Sekukonke, izinhlobo eziyisi-7 zezimfudu zihlala olwandle lwezindawo ezipholile nezishisayo, futhi impilo yazo ihlale igcwele izingozi, futhi ukufudumala kwembulunga yonke okubangelwa umsebenzi womuntu kuye kwanzima nakakhulu.
Izimfudu zasolwandle zizalela amaqanda azo ogwini olunesihlabathi, futhi izimfudu eziningi ezincane azichanyuseli nokuchanyuselwa. Amaqanda angabulawa amagciwane, ambiwe izilwane zasendle, noma achotshozwe ezinye izimfudu ezimba izidleke ezintsha. Zona lezi zimfudu ezikwazile ukugqashula emagobolondweni azo antekenteke kuzofanele zifike olwandle, zibeke engcupheni yokubanjwa yinqe noma i-raccoon - kanti izinhlanzi, izinkalankala nezinye izilwane zasolwandle ezilambile zibalindile emanzini. I-1% kuphela yamaphuphu ofudu lwasolwandle achanyuselwa asinda aze abe madala.
Izimfudu ezikhulile nazo zibhekana nezilwane ezidla ezinye zemvelo ezifana noshaka we-tiger, ama-jaguar kanye nemikhomo ebulalayo.
Nokho, kwakungabantu abanciphisa kakhulu amathuba ezimfudu zasolwandle ukuze ziphile.
Emabhishi lapho izimfudu zihlala khona, abantu bakha izindlu. Abantu bantshontsha amaqanda ezidlekeni bawadayise emakethe, babulale izimfudu ezindala ukuze bathole inyama nesikhumba, okusetshenziselwa ukwenza amabhuzu nezikhwama. Ngamagobolondo ofudu, abantu benza amasongo, izibuko, amakamu namabhokisi obucwebe. Izimfudu ziwela emanetheni ezikebhe zokudoba futhi zife ngaphansi kwezinsimbi zemikhumbi emikhulu.
Njengamanje, izinhlobo eziyisithupha kweziyisikhombisa zezimfudu zasolwandle zibhekwa njengezisengozini. Mayelana nezinhlobo zesikhombisa - ufudu oluluhlaza lwase-Australia - ososayensi bamane bengenalo ulwazi olwanele lokunquma ukuthi siyini isimo salo.
Ucwaningo olusha - ithemba elisha?
Kolunye ucwaningo, u-Allen wathola ukuthi endaweni encane yezimfudu zasolwandle eziluhlaza ngaphandle kwaseSan Diego, izihlabathi ezifudumalayo zandisa inani labesifazane lisuka ku-65% laya ku-78%. Ukuthambekela okufanayo kuye kwaphawulwa ezixukwini zezimfudu zasolwandle okuthiwa ama-loggerhead kusukela eNtshonalanga Afrika kuya eFlorida.
Kodwa akekho owake wahlola izimfudu eziningi noma eziningi eSiQhingini SaseRhine. Ngemva kokwenza ucwaningo kulesi sifunda, u-Allen noJensen benza iziphetho ezibalulekile.
Izimfudu ezindala ezachanyuselwa emaqandeni eminyakeni engu-30-40 edlule nazo zaziyizinsikazi, kodwa ngesilinganiso esingu-6:1 kuphela. Kodwa izimfudu ezincane zizalwe ngaphezu kwama-20% abesifazane okungenani iminyaka engu-99 edlule. Ubufakazi bokuthi ukunyuka kwamazinga okushisa bekuyimbangela yiqiniso lokuthi endaweni yaseBrisbane e-Australia, lapho izihlabathi zipholile khona, abesifazane badlula abesilisa ngesilinganiso nje esingu-2:1.
Okunye ukuhlola eFlorida kwathola ukuthi izinga lokushisa liyisici esisodwa nje. Uma izihlabathi zimanzi futhi zipholile, abesilisa abaningi bayazalwa, futhi uma izihlabathi zishisa futhi zomile, kuzalwa abesifazane abaningi.
Ithemba liphinde lanikezwa wucwaningo olusha olwenziwe ngonyaka odlule.
Ukusimama kwesikhathi eside?
Izimfudu zasolwandle zikhona ngendlela eyodwa iminyaka engaphezu kwezigidi ezingu-100, zisinda enkathini yeqhwa ngisho nokushabalala kwama-dinosaurs. Ngokunokwenzeka, baye basungula izindlela eziningi zokusinda, okuvele ukuthi enye yazo, engashintsha indlela abashada ngayo.
Esebenzisa ukuhlolwa kofuzo ukutadisha iqembu elincane lezimfudu ezisengozini yokushabalala e-El Salvador, umcwaningi wofudu u-Alexander Gaos, esebenzisana no-Allen, wathola ukuthi izimfudu zasolwandle zesilisa zihlangana nezinsikazi eziningi, cishe ngama-85% abesifazane enzalweni yazo.
“Sithole ukuthi leli qhinga lisetshenziswa kubantu abancane, abasengozini, abancipha kakhulu,” kusho uGaos. "Sicabanga ukuthi bebesabela nje ekutheni abesifazane bebenokuncane ukukhetha."
Ingabe kungenzeka ukuthi lokhu kuziphatha kunxephezela ukuzalwa kwabesifazane abaningi? Akunakwenzeka ukusho ngokuqinisekile, kodwa iqiniso lokuthi ukuziphatha okunjalo kungenzeka lisha kubacwaningi.
Phakathi naleso sikhathi, abanye abacwaningi abaqapha i-Dutch Caribbean bathole ukuthi ukunikeza umthunzi owengeziwe ovela emaqabunga esundu emabhishi afulelayo kupholisa isihlabathi ngokuphawulekayo. Lokhu kungasiza kakhulu ekulweni nenkinga yamanje yesilinganiso sobulili sezimfudu zasolwandle.
Ekugcineni, abacwaningi bathola idatha entsha ikhuthaza. Izimfudu zasolwandle zingase zibe uhlobo olukwazi ukuqina kunalokho obekucatshangwa ngaphambilini.
“Singase silahlekelwe abantu abambalwa, kodwa izimfudu zasolwandle azisoze zaphela nya,” kuphetha u-Allen.
Kodwa kubalulekile ukuqonda ukuthi izimfudu zingadinga usizo oluthe xaxa kithina bantu.