Kogin dolphin Karamar dabba ce ta dabbobi wacce ke cikin tsarin kayyakin halittar dabbobi. Masana kimiyya a yau sun kaskantar da kifayen kogin a matsayin nau'ikan halittu da ke cikin hatsari saboda yawan jama'a ya ragu a cikin 'yan shekarun nan sakamakon gurbacewar muhalli.
An rarraba kifayen dolphin a bakin kogi da kuma bakin teku na Asiya da Kudancin Amurka. A yau, kifayen dolphin suna rayuwa ne a iyakantattun sassan tafkin Yangtze, Mekong, Indus, Ganges, Amazon da Orinoco da kuma bakin teku na Asiya da Kudancin Amurka.
Asalin jinsin da bayanin
Hotuna: Kogin Dolphin
Masana burbushin halittu sunyi wani bincike wanda zai iya bayyanawa game da magabatan kifayen kogin, duk da cewa asalinsu ya bar tambayoyi da yawa. Kakanninsa na iya barin teku don samun ruwa mai kyau lokacin da hauhawar teku ta buɗe sabbin wuraren zama kimanin shekaru miliyan 6 da suka gabata.
A cikin 2011, masu bincike sun gano burbushin halittar dolphin na ruwa wanda kwatancen jikin mutum ya nuna yana da kusanci sosai da dabbar Amazon. An gano ragowar a wani wuri kusa da gabar tekun Caribbean na Panama. Abubuwan da aka kiyaye wadanda bazasu ɓace ba sun haɗa da ƙwanƙwasa kai, ƙananan muƙamuƙi, da haƙori da yawa. Sauran burbushin da ke cikin duwatsun da ke kewaye sun taimaki masana kimiyya sun rage shekarun dabbar dolphin zuwa kewayon miliyan 5.8 zuwa miliyan 6.1.
Bidiyo: Kogin Dolphin
Ana kiranta Isthminia panamensis, cakuda ne da sunan kifin yau na dolphin na Amazon da kuma wurin da aka sami sabon nau'in, dabbar dolfin ta kai kimanin mita 2.85 a tsayi. Siffar kan santimita 36, wacce take kallon madaidaiciya maimakon ta ɗan sauka ƙasa kamar dabbobin dolphin na zamani, ya nuna cewa dabba mai shayarwa ta shafe mafi yawan lokacin ta a cikin teku kuma wataƙila ta ci kifi, masana kimiyya sun ce.
Dangane da yanayin halittar burbushin halittu, Isthminia ko dai dangi ne na kusa ko kakanni na dabbar dolphin ta zamani. Hakanan mai ma'ana shine ka'idar cewa jinsin da aka samo asalinsa ne na tsoho kuma har yanzu ba a gano dolphin kogin da ya komo teku ba.
Bayyanar abubuwa da fasali
Photo: Kogin dabbar dabbar
A halin yanzu akwai nau'ikan kogin dolphin guda huɗu:
- Dabbar dolfin ta kogin Amazon dabba ce mai ƙarfi mai ƙanƙan da idanu da ƙaramin bakin bakin ciki, mai ɗan lankwasa zuwa ƙarshen. Su kaɗai ne haƙun haƙuran haƙori waɗanda haƙoransu suka bambanta a cikin muƙamuƙi, gaban shine fasalin mai sauƙin sauƙi na yau da kullun, yayin da aka yi niyyar baya don taimakawa wajen murƙushe abubuwan farauta. Ramin mai kama da jinjirin wata yana gefen hagu na tsakiyar kai a kai, wuya yana da sassauci sosai saboda kashin wuyan wuyan mahaifa da ba a gauraya ba kuma yana da fadi a fili. Dolphin na Amazon yana da ƙarancin ƙarancin dorsal. Abubuwan ƙafafun suna triangular, wide kuma suna da m tips. Oneayan halayen mafi ban sha'awa na wannan nau'in shine launinsa daga fari / launin toka zuwa ruwan hoda. Wasu mutane, duk da haka, suna da ruwan hoda mai haske;
- Baiji dolphin ruwa ne da ke rayuwa a Kogin Yangtze kawai. Wannan nau'in launin shuɗi ne mai launin shuɗi ko launin toka da fari a gefen iska. Hakanan yana da ƙananan, fin fes, mai tsawo, bakin da aka ɗauke, da ƙananan idanu da aka girke bisa kan sa. Saboda rashin gani sosai da kuma ambaliyar ruwan Kogin Yangtze, Baiji ya dogara da sauti don sadarwa;
- Ganges na Ganges yana da ƙarfi da sassauƙa tare da ƙananan ƙwanƙolin triangular. Weights har zuwa 150 kg. Yaran yara suna launin ruwan kasa a lokacin haihuwa kuma suna canza launin launin toka a cikin girma tare da fata mai laushi da gashi. Mata sun fi maza girma. Matsakaicin tsayin mace ya kai mita 2.67, na namiji kuma ya kai mita 2.12. Mata na kai wa ga girma ga jima’i tun suna da shekaru 10-12, yayin da maza ke girma a baya;
- An san kifin doli na La Plata saboda bakinsa mai tsayi, wanda ake ɗauka mafi girman sanannun dabbobin dolphin. A matsakaici, wakilan wannan nau'in sun kai mita 1.5 a tsayi kuma suna da nauyin kilogram 50. Finarshen dorsal yana da siffar mai kusurwa uku tare da gefen zagaye. Dangane da launi, waɗannan dolphins suna da launin launin ruwan kasa mai launin toka-toka tare da launi mai launi a ciki.
Ina dolphins na kogi ke rayuwa?
Hotuna: Pink River Dolphin
Ana samun kifin dolphin na Amazon a cikin rafin Orinoco da Amazon, a cikin tushen rafuka, rafinsu da tafkuna, kodayake a wasu wurare an iyakance kewayon ta da ci gaban da kuma gina madatsun ruwa. A lokacin damina, matsugunan sun fadada zuwa dazuzzuka da ambaliyar ruwa.
Baiji, wanda aka fi sani da Yangtze Delta Dolphin na kasar Sin, dolphin mai ruwa ne. Baiji yawanci yana haɗuwa biyu-biyu kuma yana iya haɗuwa a cikin manyan rukunin zamantakewar mutane daga 10 zuwa 16 mutane. Suna cin abinci a kan ƙananan ƙananan kifin ruwa, suna amfani da dogon bakinsu dan kaɗan don bincika laka kogin China.
WWF-Indiya ta gano wuraren zama mafi kyau a wurare 9 a cikin rafuka 8 don yawan kogin Ganges na kogin Ganges kuma saboda haka ayyukan kiyaye fifiko. Waɗannan sun haɗa da: Babban Ganga (Bridghat zuwa Narora) a Uttar Pradesh (wanda ake zargi da suna Ramsar Sanctuary), Kogin Chambal (har zuwa nisan kilomita 10 na tsabtar Tsubirin Dajin Chambal) a Madhya Pradesh da Uttar Pradesh, Gagra da Kogin Gandak a cikin Uttar Pradesh da jihar Bihar, Ganga kogi, daga Varanasi zuwa Patna a Uttar Pradesh da Bihar, Son da Kogin na Bihar, Kogin Brahamaputra a yankin Sadia (tsaunukan Arunachal Pradesh) da Dhubri (iyakar Bangladesh), Kulse da kuma masarautar Brahamaputra.
Ana samun dolphin na La Plata a cikin ruwan gabar tekun Atlantika a kudu maso gabashin Kudancin Amurka. Wasu daga cikin yankuna da suka fi dacewa wanda za'a iya samun su sun hada da gabar tekun Argentina, Brazil, da Uruguay. Ba a sami wani muhimmin nazari game da ƙaura ba, duk da haka ƙananan bayanan dabbar dolphin suna ba da shawara mai ƙarfi cewa ƙaura ba ta faruwa a wajen yankin yankin bakinsu.
Menene kifin dabbar dolfin yake ci?
Photo: Freshwater Dabbar ruwa
Kamar sauran dabbobin ruwa, nau'ikan kogin suna cin abincin kifi. Abincin su ya kunshi kusan nau'in 50 na kananan kifin ruwa. Dabbobin dolphin sau da yawa suna farauta ta hanyar dogayen bakinsu, masu ɗan kaɗan a murƙushe a tsakanin rassan bishiyoyin da ke baje a kan gado.
Duk dabbobin dolphin suna samun abinci ta amfani da echolocation ko sonar. Wannan hanyar sadarwar tana da mahimmanci musamman ga kifayen dolphin lokacin farauta, saboda iya gani a cikin wuraren zama masu duhu ba shi da kyau. Kogin dolphin yana gano kifin ta hanyar tura kararraki mai karfin gaske daga kambin kansa. Lokacin da wadannan raƙuman ruwa masu sauti suka isa kifin, sai su koma ga dolphin, wanda ke hango su ta cikin dogon kashin kashin baya, wanda yake kusan kamar eriya. Dabbar dolfin sai tayi iyo ta kamo kifin.
Yawancin kifin da ke cikin abincin kogin dolphin suna da ƙoshin gaske idan aka kwatanta da kifin teku. Dayawa suna da tsayayyun jikin, kusan "masu sulke", wasu ma harma suna kare kansu da kaifi, da kaifi mai tsayi. Amma ba za a iya kwatanta wannan kariya da ƙarfin muƙamuƙin dabbar dolphin mai ɗanɗano da haƙoran "makamai" ba. An tsara haƙoran da ke gaban muƙamuƙi don hudawa da riƙe ma kifin kifi mafi wahala; hakoran da ke baya suna samar da kayan aiki mai kyau da rashin jin kai.
Da zaran an kamo kifin an murkushe shi, dabbar dolfin ta hadiye shi ba tare da tauna ba. Daga baya, zai iya tofa ƙasusuwan kashin baya da sauran ɓangarorin ganimar ganima. Abubuwan da aka lura sun nuna cewa ciyarwar ta yadu, yana nuna cewa wasu dabbobin dolphin na iya farauta tare don neman abinci.
Fasali na ɗabi'a da salon rayuwa
Hotuna: Kogin Dolphin
Dabbobin dolphins halittu ne masu kirki waɗanda suka rayu a cikin ruwa mai tsawan ƙarni da yawa. Galibi ana ganin su kaɗai ko kuma a nau'i biyu a lokacin saduwa, waɗannan dabbobin dolphin sau da yawa sukan taru a rukunin mutane 10 zuwa 15 lokacin da isasshen abin farauta. Kamar sauran nau'ikan, waɗannan dabbobin dolphin suna bacci da ido ɗaya a buɗe.
Yawanci, waɗannan halittu masu jinkirin ninkaya ne, kuma galibi suna da damuwa. Kogin dolphins suna aiki tun sanyin safiya har zuwa dare. Suna numfasawa ta amfani da fincinansu da bakinsu a lokaci guda.
Ba safai ake ganin dabbobin dolphin suna tsalle a saman ruwan ba. Koyaya, misali, dolphins na Amazon yawanci suna iyo sama da ƙasa. Dalilin wannan halin har yanzu ba a sani ba. An yi imanin cewa yawan kumatun waɗannan kifayen dolphin suna yin cikas ga hangen nesan su, saboda haka ne dolphins din suke juyowa don ganin gindin.
Tsarin zamantakewa da haifuwa
Hoto: Dabbar dabbar dabba
Kogin dolphin sau da yawa suna wasa tare. Wannan sanannen hali ne ga dabbobin kifin kifi. Koyaya, masana kimiyya daga baya sun gano cewa maza ne kawai ke wasa yayin lokacin saduwa. Idan dolphin mace ta balaga, za ta iya jan hankalin namiji ne kawai. Don haka, akwai gasa mai yawa tsakanin maza. A wasansu na wasa, wasu lokuta sukan jefa shuke-shuke na ruwa a kusa dasu. Mafi kyawun 'yan wasan maza suna karɓar kulawa sosai daga mata.
Ba da dadewa ba, ya zama cewa dabbobin dolphin suna rayuwa su kadai a mafi yawan lokuta. Mata na balaga tun suna shekara bakwai. Lokacin daukar ciki (lokacin daga daukar ciki zuwa haihuwa) yana dauke da watanni 9 zuwa 10.
Kodayake kiwo na iya faruwa a kowane lokaci na shekara, watannin farko sun fi wadata. Koyaya, haihuwar da ke faruwa a karkashin ruwa masana kimiyya ba su taɓa lura da ita ba. Nan da nan bayan haihuwa, wasu mata suna tura ɗan maraƙin saman ruwan don ya fara numfashi.
Bayan haihuwa, mace na iya ci gaba da shayar da ɗan maraƙin har na tsawon watanni 12, kodayake abubuwan lura sun nuna cewa, a matsakaita, dolphin yawanci yakan rabu da mahaifiyarsa bayan onlyan watanni kawai. Matsakaicin lokacin rayuwar dabbobin dolphins shekaru 30 ne.
Abokan gaba na dabbobin dolphins
Hoto: Kogin Kogin Sin
Babban barazanar da ake yi wa kogin dolphin shi ne farauta, inda ake amfani da dabbobi ko dai a matsayin tarko ko kuma masunta na kallonsu a matsayin masu gasa. Sauran barazanar da ke tattare da jinsin sun hada da fallasa dan adam, shiga cikin kayan kamun kifi, karancin abinci, da gurbataccen sinadarai. Kogin dolphin suna cikin haɗari akan Lissafin IUCN.
Kogin dolphins na fuskantar barazanar gaske ta hanyar gurɓata mahalli da gurɓataccen yanayi, lalata bishiyoyi, gina madatsar ruwa da sauran lamuran ɓarnata. Gurbatar sinadarai daga birane, sharar masana'antu da aikin gona da kwararar ruwa yana raunana garkuwar jikin kifin dabbobin dolphin, yana barin dabbobi cikin saukin kamuwa da cututtuka.
Tasirin amo yana tsangwama tare da ikon kewayawa. Yin sare dazuzzuka na rage yawan kifaye a cikin rafuka, yana hana kifin dolphin babban abincinsu. Haka kuma sare daji yana canza yanayin ruwan sama, wanda kan haifar da faduwar matakan ruwa a koguna. Matakin faduwar ruwa yana jan kifin dolphin a cikin tafkunan bushewa. Gandun dajin da dillalan dutsen ke kai tsaye kai tsaye tare da koguna.
Fiye da kamun kifi ya haifar da raguwar wadatar fauna a cikin koguna da tekuna, yana sanya dabbobin dolphin cikin gasa kai tsaye da mutane don abinci. Ana kama kifayen dolphin sau da yawa cikin raga da kogin kifi ko kuma mamakin abubuwan fashewar da ake amfani da su don kama kifi.
Yawan jama'a da matsayin jinsin
Hotuna: Kogin Dolphin
Duk dabbobin dolphins suna amfani da tsarin sauye-sauye na zamani don gano abokan tarayya da farauta. A da, kifayen dolphin da mutane sun kasance tare cikin lumana tare da kogin Mekong, Ganges, Yangtze da Amazon. Mutane a al'adance suna raba kifi da ruwan kogi tare da dabbobin dolphin kuma sun haɗa dabbobin dolphin a cikin tatsuniyoyi da labarai. Waɗannan imanin na gargajiya sun taimaka wa dabbobin dolphin sun rayu. Koyaya, a yau wasu mutane ba sa bin abin da aka hana a cutar da dabbobin dolphin da kashe dabbobi da yawa.
Dam da sauran lamuran lalata a cikin koguna suna shafar kifin dolphins, yana rage yawan kifi da matakan oxygen. Madatsun ruwa galibi suna rage gudana ta hanyar ɗebo ruwa mai kyau a magudanan ruwa da magudanan ruwa. Hakanan madatsun ruwa sun raba yawan kogin dolphin zuwa kananan kungiyoyi da kebanta da jinsinsu wadanda suka zama masu matukar saurin halaka.
Dams suna canza yanayin, suna tilasta koguna yin manyan canje-canje. Wannan lamarin yana rage yiwuwar samuwar wuraren da aka fi so don dabbobin dolphins. Tsarin lalacewa kamar tashoshin yin famfo da ayyukan ban ruwa suna yin mummunan tasiri ga mazaunin kogin kifayen ruwa kuma yana shafar ikon dabbobi na haifuwa da rayuwa.
Koyaya, duk da cewa mutane suna sane da halin da dabbobin dolphin suke ciki kuma suna kokarin kiyayewa, yawan dabbobi na ci gaba da raguwa a duniya. A lokuta da yawa, ragin yana da mahimmanci. Wasu mutane sun rasa bambancin kwayoyin da ake buƙata don tsira daga barazanar gajere da ta dogon lokaci, gami da canjin yanayi da ƙarancin ganima.
Kariyar kogin dolphin
Hotuna: Kogin Red Dolphin Red Book
Kogin dolphins na kan hanyar bacewa, musamman saboda ayyukan mutane. An kiyasta cewa dabbobi kusan 5,000 ne suka zauna a Kogin Yangtze a shekarun 1950, 300 a tsakiyar 1980s, sannan dabbobi 13 ne kawai aka gani a binciken a ƙarshen shekarun 1990. A shekarar 2006, wata kungiyar masana kimiyya ta kasa da kasa ta sanar da cewa wannan nau'in kifin na kogin kasar Sin “ya mutu,” saboda ba a ga kifayen dolphin a yayin binciken makonni 6 na kogin Yangtze baki daya ba.
Ana ɗaukar matakan kariya dabbar dolphin tare da rafuka da bakin teku a duniya. Kokarin kiyayewa ya hada da ayyukan bincike, sake matsuguni da kiwon dabbobi, da dokoki kan kisan kai da cutar dabbobi.
Ana gudanar da bincike na kimiyya, sake matsuguni da kiwo cikin bayi a cikin jeji da bayan. Masu binciken sun kirkiro yanayi da kuma kayan adana kayan kwalliyar dabbobin dolphin. An kafa Yankunan Kogin Dolphin don Kogin Amazon da koguna da kuma tsattsauran ra'ayi a Asiya. Ana gudanar da ayyukan al'umma don inganta hanyoyin ci gaba mai dorewa ga kamun kifi da haɓaka shirye-shiryen kiyaye gida wanda zai ba mutane da dabbobin dolphin damar raba albarkatun kogi. Dokokin ƙasa da na ƙasa sun kuma hana kisa ko cutar dabbobin dolphin a kogin duniya.
Yawan kogin dolphin a halin yanzu yana kunshe da adadi mai yawa na dabbobi, wanda ke iyakance ikon haifuwa da juriya da irin waɗannan abubuwa na mace-mace kamar lalata mahalli. Kogin dolphin ya sa yawancin masu kula da muhalli suka yi kira da a hada karfi da karfe a kasashen duniya don ganin an kubutar da dabbobin dolphin daga bacewa domin gudanar da ayyukan mutane ta hanyar koguna. Duk waɗannan ayyukan dole ne don mutane da namun daji na cikin ruwa su iya zama cikin lumana.
Ranar bugawa: 21.04.2019
Ranar sabuntawa: 19.09.2019 a 22:13
