Giwar Ruwa - haƙiƙa ce ta gaske, ko hatimi ba tare da kunnuwa ba, mambobi ne na ɓangaren yanki. Waɗannan halittu ne masu ban mamaki: manya masu ƙiba tare da hanci, mata masu ban sha'awa waɗanda da alama suna murmushi koyaushe, da kyawawan pla cuban withasa masu tsananin sha'awa.
Asalin jinsin da bayanin
Photo: Giwar hatimin
Hatimin giwar shine mai nitsewa a cikin teku, matafiyi mai nisa, dabba mai yunwa na tsawan lokaci. Hannun giwaye na ban mamaki ne, sun haɗu a kan ƙasa don haihuwa, mata da narkar da jiki, amma su kaɗai ne a cikin teku. Ana sanya manyan buƙatu akan bayyanar su don ci gaba da tseren su. Bincike ya nuna cewa hatimin giwaye 'ya'yan dolphin ne da na platypus ko na dolphin da na koala.
Bidiyo: Sefan giwa
Gaskiya mai ban sha'awa: Wadannan manyan finafinan ba a ba wa suna tambarin giwa saboda girman su. Sun samo sunansu ne daga muzzles masu zafin nama wanda suke kama da giwar giwa.
Tarihin bunkasar mulkin mallaka na giwayen giwaye ya fara ne a ranar 25 ga Nuwamba, 1990, lokacin da aka ƙidaya mutane ɗari biyu daga waɗannan dabbobin a cikin wani ƙaramin mashigar ruwa ta kudu na hasumiyar Piedras Blancas. A cikin bazarar 1991, kusan like 400 aka bred. Haihuwar farko ta kasance a cikin watan Janairun 1992. Mulkin mallaka ya yi girma sosai. A cikin 1993, an haifi kusan yara 50. A cikin 1995, an haifi wasu yara 600. Fashewar jama'a ya ci gaba. Zuwa 1996, yawan yaran da aka haifa sun karu zuwa kusan 1,000, kuma mulkin mallaka ya fadada har zuwa rairayin bakin teku tare da babbar hanyar bakin teku. Mulkin mallaka ya ci gaba da faɗaɗawa a yau. A shekarar 2015, akwai tambarin giwaye 10,000.
Bayyanar abubuwa da fasali
Hoto: Yaya tambarin giwa yake
Hannun giwaye dabbobi ne masu ma'amala na dangin Phocidae. Hatimin giwar arewacin yana da launin rawaya ko launin toka-launin ruwan kasa, yayin da hatimin giwar na kudu mai launin shuɗi-shuɗi. Nau'in kudancin yana da lokacin zubar da jini mai yawa, yayin da manyan wurare na gashi da fata suka faɗi. Maza na duka jinsunan sun kai kimanin mita 6.5 (ƙafa 21) a tsayi kuma suna da nauyin kilogram 3,530 (7,780 lb) kuma sun fi mata girma sosai, waɗanda wani lokacin sukan kai mita 3.5 kuma suna da nauyin 900.
Alamun giwaye sun kai saurin 23.2 km / h. Mafi yawan nau'in dabbobin da suka wanzu a rayuwa sune hatimin giwar kudu. Maza na iya zama sama da mita 6 tsayi kuma nauyinsu ya kai tan 4.5. Hannun teku suna da faɗi, zagaye fuska da manyan idanu. Ana haihuwar 'Ya'ya tare da baƙar fata mai ɗorawa a yaye (kwanaki 28), an maye gurbinsu da santsi, launin ruwan toka mai launin shuɗi. A tsawon shekara, gashin zai canza launin azurfa zuwa launin ruwan kasa.
Hannun giwayen mata suna haihuwa a karon farko kusan shekara 4, duk da cewa jeri daga shekaru 2 zuwa 6. Mata ana ɗaukarsu manyanta ne tun suna da shekaru 6. Maza sun isa balaga a kusan shekara 4 lokacin da hanci ya fara girma. Hanci halayyar jima'i ce ta sakandare, kamar gemu ta mutum, kuma tana iya kaiwa tsayi mai ban mamaki na rabin mita. Maza sun isa balaga ta jiki kusan shekaru 9 da haihuwa. Babban shekarun kiwo shine shekaru 9-12. Hannun giwayen Arewa suna rayuwa kimanin shekaru 9, yayin da giwayen kudanci ke rayuwa shekaru 20 zuwa 22.
Mutane suna zubar da gashi da fata koyaushe, amma hatta giwayen suna wucewa ta cikin wani mummunan bala'i, inda dukkanin layin epidermis ɗin tare da gashin da aka haɗe suke mannewa a wani lokaci a lokaci. Dalilin wannan ƙazamar molt shine mafi yawan lokacinsu a cikin teku cikin ruwan sanyi mai zurfi. A lokacin nutsewar, ana zubar da jini daga fatar. Wannan yana taimaka musu wajen kiyaye kuzari da rashin zafin jiki. Dabbobi na ninkaya a ƙasa yayin narkar da su, saboda jini na iya zagayawa cikin fata don taimakawa girma da sabon fatar epidermis da gashi.
A ina ne giwayen hatimin ke rayuwa?
Hotuna: Katin Giwar Kudancin
Akwai hatimin giwa iri biyu:
- arewa;
- kudu.
Ana samun tambarin giwayen Arewa a cikin Tekun Arewacin Pacific daga Baja California, Mexico zuwa Tekun Alaska da Tsubirin Aleutian. A lokacin kiwonsu, suna rayuwa ne a bakin rairayin bakin teku a tsibirin da ke gabar teku da kuma wurare da yawa a cikin babban yankin. Sauran shekara, ban da lokutan ɓarna, raƙuman giwayen suna zaune a nesa da teku (har zuwa kilomita 8,000), galibi suna nitsewa sama da mita 1,500 ƙasa da saman teku.
Hannun giwayen Kudancin (Mirounga leonina) suna zaune a cikin yankin Antarctic da kuma ruwan Antartika masu sanyi. An rarraba su ko'ina cikin Tekun Kudancin da ke kusa da Antarctica da kuma a mafi yawan tsibirin tsibiri. Jama'a suna mai da hankali ne kan Tsibirin Antipodes da Tsibirin Campbell. A lokacin sanyi, galibi suna ziyartar tsibirin Auckland, Antipodes da Snares, ba sau da yawa tsibirin Chatham da wasu lokuta manyan yankuna daban-daban. A wasu lokutan hatimai giwayen na kudanci suna ziyartar yankunan bakin teku na babban yankin New Zealand.
A cikin babban yankin, suna iya zama a yankin na tsawon watanni, suna ba mutane dama su lura da dabbobin da yawanci suke rayuwa a cikin ruwa. Alheri da saurin irin waɗannan manyan dabbobi masu shayarwa na iya zama abin birgewa, kuma hatimin samari na iya zama da wasa sosai.
Gaskiya mai ban sha'awa: Ba kamar sauran dabbobi masu shayarwa na teku ba (kamar su whales da dugongs), hatta giwayen ba cikakkun halittun ruwa bane: suna fitowa daga cikin ruwa don hutawa, narkakkiyar aure, da haihuwa, kuma suna haihuwar ƙuruciya.
Me hatimin giwa yake ci?
Hoto: Hatimin giwar mata
Hatunan giwaye masu cin nama ne. Hannun giwayen kudu masu farautar teku ne kuma suna cinye mafi yawan lokacinsu a cikin teku. Suna ciyar da abinci akan kifi, squid ko wasu kifayen da ake samu a cikin ruwan Antarctic. Suna zuwa bakin teku ne kawai don kiwo da narkar da jiki. Suna shafe sauran shekara suna ciyarwa a cikin teku, inda suka huta, suna iyo a saman kuma suna nutso don neman babban kifi da kifi. Yayinda suke cikin teku, galibi ana ɗauke su daga wuraren kiwo, kuma suna iya yin tafiya mai nisa sosai tsakanin lokutan da aka yi amfani da su a ƙasa.
An yi imanin cewa mata da maza suna ciyar da ganima daban. Abincin mata yawanci squid ne, yayin da abincin maza ya bambanta, ya ƙunshi ƙananan kifaye, haskoki da sauran kifin na ƙasa. Don neman abinci, maza suna tafiya tare da gandun daji na duniya zuwa Tekun Alaska. Mata suna zuwa arewa da yamma zuwa cikin buɗewar teku. Hatimin giwaye yana yin wannan ƙaura sau biyu a shekara, kuma yana dawowa cikin rookery.
Alamu na giwaye suna ƙaura don neman abinci, suna yin watanni a cikin teku, kuma galibi suna nitsewa cikin neman abinci. A lokacin hunturu, suna komawa cikin rudanin su don haifuwa da haihuwa. Kodayake hatimin giwayen mata da na mata suna ciyar da lokaci a cikin teku, amma hanyoyinsu na ƙaura da halaye na ciyarwa sun bambanta: maza suna bin wata hanya madaidaiciya, farauta tare da sashin ƙasa da abinci a farfajiyar tekun, yayin da mata ke canza hanyoyinsu don neman abin farauta da farauta mafi yawa a cikin teku. Rashin samun karin haske, giwayen giwayen suna amfani da idanuwansu da bakinsu don jin motsin da ke kusa.
Fasali na ɗabi'a da salon rayuwa
Photo: Seal giwa a yanayi
Alamun giwaye suna zuwa bakin teku suna kafa yankuna na aan watanni kaɗan a shekara don haihuwa, haifuwa, da narkar da jiki. Sauran shekara, yankuna sun watse, kuma mutane suna amfani da mafi yawan lokacinsu don neman abinci, tafiyar dubban mil mil da zurfin zurfafawa. Yayin da tambarin giwaye ke cikin teku don neman abinci, sai suka nitse zuwa zurfin zurfafawa.
Galibi suna nitsewa zuwa zurfin kusan mita 1,500. Matsakaicin lokacin nutsewa shine mintuna 20, amma zasu iya nitsewa na awa ɗaya ko fiye. Lokacin da giwayen giwayen suka zo saman, sai su kwashe mintuna 2-4 kawai a kan ƙasa kafin su sake nutsewa - kuma su ci gaba da wannan aikin nutsar awanni 24 a rana.
A kan ƙasa, hatiman giwaye galibi ana barin su ba tare da ruwa ba na dogon lokaci. Don gujewa bushewar jiki, kodar su na iya samar da fitsari mai karfi, wanda ke dauke da karin shara da karancin ruwa a kowane digo. Rookery wuri ne mai yawan hayaniya a lokacin kiwo, yayin da maza ke yin kuwwa, 'yayan suna ihu don ciyarwa, kuma mata suna jayayya da junan su akan kyakkyawan wurin da yaran. Gurnani, zugar ciki, bel, ɓoke, kururuwa, kururuwa da hayaniyar maza suna haɗuwa don ƙirƙirar rawar muryar hatimin giwa.
Tsarin zamantakewa da haifuwa
Hotuna: Jaririn Giwar Giwa
Hatimin giwar kudu, kamar hatimin giwar arewa, yana hayayyafa da narkar da ƙasa, amma masu hibernates a cikin teku, mai yiwuwa kusa da kankara. Hannun giwayen Kudancin kan hayayyafa a kan ƙasa amma suna yin hunturu a cikin ruwan Antarctic mai sanyi kusa da kankara Antarctic. Nau'in arewacin ba ya yin ƙaura yayin haifuwa. Lokacin da lokacin kiwo ya isa, hatta giwayen maza suna ayyanawa da kare yankuna kuma su zama masu faɗa da juna.
Suna tattara mata 40 zuwa 50 na mata, waɗanda suka fi girma girma fiye da manyan abokan aikinsu. Maza suna fada da juna don ikon mallakar jima'i. Wasu rikice-rikice suna ƙarewa da ruri da tashin hankali, amma wasu da yawa sun rikide zuwa faɗa mai zafi da jini.
Lokacin kiwo yana farawa a ƙarshen Nuwamba. Mata suna fara zuwa a tsakiyar Disamba kuma suna ci gaba da zuwa har tsakiyar Fabrairu. Haihuwar farko ana yin ta ne kusa da ranar Kirsimeti, amma yawancin haihuwar galibi ana yin ta ne a cikin makonni biyu na ƙarshe na Janairu. Mata sun kasance a rairayin bakin teku na kimanin makonni biyar daga lokacin da suka zo bakin teku. Abin mamaki, maza suna zama a bakin rairayin har tsawon kwanaki 100.
Lokacin ciyar da madara, mata ba sa cin abinci - uwa da yaro suna raye da kuzarin da aka tara a wadataccen kitsenta. Dukansu maza da mata sun rasa kusan 1/3 na nauyinsu a lokacin kiwo. Mata suna haihuwa sau ɗaya a kowace shekara bayan watanni 11 na ciki.
Gaskiya mai ban sha'awa: Lokacin da mace ta haihu, madarar da take asirinta tana da kusan 12% mai kiba. Makonni biyu bayan haka, wannan lambar ya ƙaru zuwa sama da 50%, yana ba wa ruwa mai kama da pudding. Idan aka kwatanta, madarar shanu ta ƙunshi mai kashi 3.5% kawai.
Abokan gaba na giwayen giwaye
Photo: Giwar hatimin
Manyan giwayen kudancin ba su da 'yan magabta, daga cikinsu:
- kifayen kifi whale, waɗanda ke iya farautar yara da tsofaffin hatimi;
- tambarin damisa, wanda wani lokaci yakan kai wa yara hari kuma ya kashe su;
- wasu manyan kifaye.
Hakanan ana iya ɗaukar membobin yawan su yayin kiwo kuma a matsayin abokan hamayyar giwayen giwaye. Alamu na giwaye suna haifar da kurege a ciki wanda babba ko haruffa ke kewaye da mata. A gefen harem, matan beta suna jira da fatan samun damar haduwa. Suna taimaka wa alpha namiji ya riƙe maza mafi rinjaye. Fada tsakanin maza na iya zama lamari na zub da jini, tare da mazaje da ke tashi tsaye da naɗa juna da juna, suna sarewa da manyan haƙoran canine.
Hannun giwaye suna amfani da haƙoransu yayin faɗa don yaye wuyan abokan hamayya. Manyan maza na iya yin mummunan rauni sakamakon faɗa tare da wasu mazan a lokacin kiwo. Yaƙe-yaƙe tsakanin manyan maza da masu ƙalubalantar na iya zama tsayi, na jini da tsananin zafin rai, kuma wanda ya kayar yakan ji rauni sosai. Koyaya, ba duk arangama ke ƙarewa da yaƙi ba. Wasu lokuta ya ishe su su hau duwawunsu na baya, su jefa kawunansu, su nuna girman hancinsu da barazanar mai karfi don tsoratar da mafi yawan masu adawa. Amma idan fadace-fadace suka faru, da wuya ya mutu.
Yawan jama'a da matsayin jinsin
Hoto: Yaya like giwayen giwaye
Dukkanin nau'ikan hatimin giwaye an yi farautar su saboda kitsensu kuma kusan an shafe su gaba ɗaya a cikin karni na 19. Koyaya, a karkashin kariyar doka, sannu a hankali lambobinsu suna ƙaruwa, kuma ba a fuskantar barazanar rayuwarsu. A cikin 1880s, hatta giwayen arewacin an yi zaton sun ƙare, saboda an yi farautar jinsunan biyu ta bakin mahauta don su sami kitsen da ke ƙarƙashinsu, wanda yake na biyu ne kawai da kitsen kifin whale a cikin inganci. Wani karamin rukuni na hatimin giwaye 20-100 waɗanda aka zana a tsibirin Guadalupe, kusa da Baja California, sun sami mummunan sakamako na farautar hatimi.
Karewar ta farko ta Mexico sannan kuma daga Amurka, koyaushe suna faɗaɗa yawan su. An kiyaye su ta Dokar Kare Dabba ta Mamiki ta 1972, suna fadada kewayonsu daga tsibirai masu nisa kuma a halin yanzu suna mallakar zababbun rairayin bakin teku na kasa kamar Piedras Blancas, a kudancin Big Sur, kusa da San Simeon. Adadin da aka kiyasta yawan hatta giwaye a shekara ta 1999 ya kusan 150,000.
Gaskiya mai ban sha'awa: Alamun giwaye namun daji ne kuma bai kamata a tunkaresu ba. Ba su da tabbas kuma suna iya haifar da babbar illa ga mutane, musamman a lokacin kiwo. Sa hannun ɗan adam na iya tilasta hatimi don amfani da kuzarin da suke buƙata don rayuwa. Kubiyoni suna iya rabuwa da iyayensu mata, wanda hakan yakan haifar da mutuwar su. Hukumar Kula da Masunta ta Kasa, hukumar tarayya da ke da alhakin aiwatar da Dokar Kare Dabbobin Dabbobin Ruwa, ta ba da shawarar a zauna lafiya mai nisan mita 15 zuwa 30.
Giwar Ruwa Dabba ne mai ban mamaki. Suna da girma da girma a ƙasa, amma suna da kyau a ruwa: zasu iya nitsewa zuwa zurfin kilomita 2 kuma su riƙe numfashin su a cikin ruwa har zuwa awanni 2. Alamun giwaye suna yawo a cikin tekun gaba ɗaya kuma suna iya iyo mai nisa don neman abinci. Suna gwagwarmaya don samun wuri a cikin rana, amma mafi ƙarfin hali ne kawai ke cimma burinsu.
Ranar bugawa: 07/31/2019
Ranar da aka sabunta: 01.08.2019 a 8:56
