Stellate sturgeon (Acipenser stellatus) yana ɗaya daga cikin manyan tsuntsaye, wanda aka sani da samar da caviar tare da beluga da sturgeon. Sevruga kuma ana kiranta da suna sturgeon saboda halayen faranti masu ƙyalli a jikinsa. An saka wannan kifin a matsayin mai hatsarin gaske. Sevruga ba zai iya jure ƙananan matakan oxygen ba, don haka ƙarin oxygenation a lokacin watannin bazara yana da mahimmanci a gare shi.
Asalin jinsin da bayanin
Hotuna: Sevryuga
Sunan da aka fi sani da wannan nau'in shine "tauraron tauraro". Sunan kimiyya "stellatus" kalma ce ta Latin mai ma'ana "an lullube ta cikin taurari." Wannan suna yana nufin fastoci masu siffar taurari da suka rufe jikin wannan dabbar.
Bidiyo: Sveruga
Sturgeon, wanda mai tauraron dan adam yake, yana daya daga cikin tsofaffin dangi na kifi mai cin nama, dan asalin karkara, mai sanyin jiki da na ruwa, tabkuna da gabar tekun Eurasia da Arewacin Amurka. An rarrabe su da tsawan jikinsu, rashin sikeli da manyan girma masu girma: sturgeons daga 2 zuwa 3 m suna da yawa, kuma wasu nau'ikan suna girma har zuwa 5.5 m. Yawancin sturgeons sune masu ba da abinci mai ƙarancin ƙyama, suna girma a sama kuma suna cin abinci a cikin kogin delta da bakin kogi. Yayin da wasu kuma gaba daya ruwan sha ne, 'yan kadan ne suka shiga cikin teku a waje da yankunan bakin teku.
Sevruga yana iyo a cikin ruwa mai ƙarancin yanayi, ruwan kwalliya da ruwan teku. Yana ciyar da kifi, molluscs, crustaceans da tsutsotsi. Ya fi zama a cikin tekun Bahar Maliya da na Caspian da kuma Tekun Azov. Mafi yawan jama'a suna cikin yankin Volga-Caspian. Akwai hanyoyi daban-daban guda biyu don wannan nau'in. Wasu kifayen suna bazuwa a lokacin hunturu wasu kuma a bazara.
Bayyanar abubuwa da fasali
Hotuna: Yaya sevruga yake?
Abubuwan da ke tattare da sturgeon sune kamar haka:
- tushe daga kwarangwal din ba kashin baya ba ne, amma cartilaginous notochord;
- fin dorsal nesa da kai;
- larvae suna ci gaba na tsawon lokaci, suna ciyar da abubuwan da ke cikin jakar kwai;
- hasken gaba na fin pectoral ƙaya ne;
- tare da jiki (a bayan baya, ciki, a tarnaƙi) akwai layuka na manyan maɓuɓɓugan maɓuɓɓuka. Tsakanin su, dabbar an rufe ta da ƙananan tarin fuka, granules.
Sevruga kifi ne mai daraja na kasuwanci. Yana da nau'i biyu - hunturu da bazara. Ya bambanta da duk sauran kifayen dangin sturgeon a cikin bayyanar. Wani fasali mai ban mamaki na tauraron tauraron ɗan adam hanci ne mai ɗauke da wuƙaƙe wanda ba a saba gani ba. Gaban wannan kifin ya shahara sosai, eriya mai santsi kuma mai santsi ba ta kai bakin, lebban ƙananan ba su da kyau sosai.
Jikin sturlate sturgeon, kamar hanci, yana da tsayi, a kowane gefe da bayanta an lullubeshi da ɓoyi, ana tazara da juna. Jikin wannan kifin ruwan kasa ne mai launin ruwan kasa-kasa tare da ɗan shuɗi mai ɗanɗano-baƙi a baya da gefuna tare da farin yadi a ciki.
Sevruga kifi ne mara kyau, wanda za'a iya rarrabe shi da bakinsa, wanda dogo ne, siriri kuma madaidaici. Garkuwa ta gefe ƙananan ne. Wadannan fasalulluka sun banbanta stargeon da sturgeon, wanda aka samo shi a cikin ruwan Finnish a cikin 'yan shekarun nan. Bayan bayan sturgeon mai duhu mai launin toka-kore ko launin ruwan kasa, ciki mai kodadde. Hanyoyin da ke gefe suna da haske. Sevruga ba shi da ƙarancin girma ga mafi yawan tsuru-tsuru. Matsakaicin nauyinta ya kai kimanin 7-10 kg, amma wasu mutane sun kai tsawon fiye da 2 m kuma nauyin 80 kg.
A ina ne tauraron tauraron dan adam ke rayuwa?
Hotuna: Sevruga a Rasha
Sevruga yana zaune ne a cikin Tekun Caspian, Azov, Black da kuma Aegean, daga inda yake shiga rafin, ciki har da Danube. Ba safai ake samun wannan nau'in a cikin Tsakiyar Tsakiyar da Danube ba, kawai lokaci-lokaci kifi kan yi ƙaura zuwa Komarno, Bratislava, Austria ko ma Jamus. Ana samun wannan nau'in a cikin adadi kaɗan a cikin Tekun Aegean da Adriatic, da kuma a cikin Tekun Aral, inda aka kawo shi daga Kogin Caspian a cikin 1933.
A yayin haifar da ƙaura, mashahurin mashahurin ya kuma shiga rafin na ofasan Danube, kamar su kogin Prut, Siret, Olt da Zhiul. A cikin Tsakiyar Danube, ta yi ƙaura zuwa Kogin Tisu (har zuwa Tokaj) da kuma zuwa ƙasan maɓuɓɓuganta, kogunan Maros da Körös, har zuwa bakin Kogin Zagyva, ƙananan ƙasan kogin Drava da Sava da bakin Kogin Morava.
Sakamakon tsari da toshewar kogi, yankin mashahurin tauraron dan adam a cikin ruwan tekun Caspian, Azov da Black ya ragu sosai. Yankin wuraren da aka samar da cibiyoyin ya ragu sosai, kuma hanyoyi da lokacin yin ƙaura sun canza. A halin yanzu, yawancin mutane a cikin Kogin Danube suna ƙaura ne kawai zuwa madatsun Gateofar ƙarfe.
Sevruga yawanci ana samunsa a cikin zurfin zurfin rairayin bakin teku da kuma a yankunan rafin kogi. Animalsananan dabbobi masu lanƙwasa sune tushen asalin abinci ga manya, kuma plankton yana taka muhimmiyar rawa wajen ciyarwa a farkon matakan larval.
Yanzu kun san inda mashahurin jaririn yake zaune. Bari mu bincika me kifin nan yake ci.
Menene tauraron tauraro ke ci?
Hotuna: Sevruga a cikin teku
Nau'ikan sturgeon guda bakwai da suka fi kowa, ciki har da sturlate stelgeon, malalar ƙura a cikin tabkuna da koguna, suna ciyarwa galibi akan kifin kifi, jatan lande, katantanwa, tsire-tsire, kwari na cikin ruwa, larvae, tsutsotsi da molluscs.
Gaskiya mai ban sha'awa: Sevruga na daina cin abinci da zarar ya fara yin ƙaura. Bayan haihuwa, da sauri ya komo teku, inda ya fara ciyarwa kuma.
Sevruga ƙwararrun masarufi ne a ƙasan saboda suna da eriya masu hankali a ƙasan hancin su don gano dabbobin ƙasa da dogon bakinsu mai girma don tsotse abincinsu. Yankin gastrointestinal na stellate sturgeons shima na musamman ne, saboda bangon ciki na pyloric suna hawan jini cikin kwayar cuta mai kama da ciki, hanjin tsofaffi suna da ruɓaɓɓen epithelium na aiki, kuma hanjin hanjinsu na baya ya zama bawul.
Stwararrun uran tsakar gida, waɗanda aka samo su a cikin tafkunan masu zaman kansu, suna buƙatar bitamin, mai, ma'adanai da aƙalla kashi 40% na furotin (mafi yawa daga naman kifi). Daga cikin bitamin masu narkewa mai narkewa, suna buƙatar bitamin A, D, E, da K. Su bitamin masu narkewa cikin ruwa sun haɗa da B1 (thiamine), B2 (riboflavin), B6, B5, B3 (niacin), B12, H, C (ascorbic acid), da folic acid.
Fasali na ɗabi'a da salon rayuwa
Photo: Stellate sturgeon kifi
Kodayake sturlate sturgeon shine tushen kiwon kifi a matsayin tushen ƙwai mai mahimmanci, amma akwai rashin cikakken sani game da ilimin halittu da halayyar wannan nau'in a cikin daji (kewayon gida, tarawa, zalunci, misali), da kuma fannoni da yawa na noma (tsokana, haɓaka mahalli) yanayi, damuwa da yanka). Rashin ilimi ba kawai yana wahalar da kimar yanayin lafiyarta sosai ba, har ma yana rikitar da kusan duk wani ci gaba na ci gabanta.
Daban-daban nau'ikan sturgeon suna filastik sosai dangane da halayyar ɗabi'a. Yawaitar yaduwar abubuwa suna faruwa yayin jinsin daya yana da rukunoni daban-daban wadanda suke zuriya a cikin tsarin kogi daya, wanda muke kira da "ninka sau biyu". Kungiyoyin spawning an bayyana su azaman bazara da tseren bazara.
An bayyana keɓaɓɓun ƙungiyoyi masu rarrafe don jinsin sturgeon da yawa a duniya. Hayayyafa iri biyu tana faruwa a yawancin jinsunan sturgeon na Eurasia. A cikin Tekun Black da Caspian akwai nau'ikan da yawa tare da bazara da jinsi na asali: beluga, Sturgeon na Rasha, ƙaya, stellate sturgeon, sterlet. Theungiyar bazara ta shiga cikin kogin yayin bazara tare da kusan manyan gonads da spawn jim kaɗan da shiga cikin kogin. Heungiyar heme ta shiga cikin kogin a lokaci guda ko kuma nan da nan bayan ƙungiyar bazara, amma tare da oocytes marasa girma.
Tsarin zamantakewa da haifuwa
Hotuna: Sevryugi daga littafin Red
Wannan nau'in ya samo asali ne a gabar kogunan da ambaliyar ruwan bazara suka yi ambaliyar kuma a saman dutsen mai tashar tashar mai saurin gudu. Qwai suna kwanciya a gadaje na duwatsu warwatse, tsakuwa da tsakuwa hade da gutsutsuren harsashi da yashi mara nauyi. Yanayin haɓaka mafi kyau duka sun haɗa da yawan kwararar ruwa da tsaunukan tsakuwa. Rage yawan gudu bayan haihuwa da ci gaban kwai na iya haifar da karuwar embryo. A cikin Kogin Danube, yaduwar yanayi yana faruwa ne daga Mayu zuwa Yuni a yanayin zafi da ya fara daga 17 zuwa 23 ° C. Ba a san abubuwa da yawa game da dabi'ar haihuwar wannan nau'in ba.
Bayan ƙyanƙyashe, ƙwayoyin lardin stellate ba kawai ƙananan ruwa da na tsakiya na ruwan kogin ba, har ma a saman. Suna yawo kai-tsaye, kuma ikonsu na motsawa yana ƙaruwa yayin ci gaba mai zuwa. Rarraba yara tare da Danube ya sami tasirin kayan abinci, na yanzu da hargitsi. Suna yin ƙaura zuwa ƙasa zuwa zurfin zurfin mita 4 zuwa 6. Tsawancin rayuwa a cikin kogin yana farawa daga Mayu zuwa Oktoba, kuma ciyarwa mai aiki yana farawa lokacin da tsutsa ta kai 18-20 mm.
Gaskiya mai ban sha'awa: Sevruga na iya kaiwa sama da mita 2 tsayi kuma matsakaicin shekaru na 35. Don maza da mata su girma, yana ɗaukar shekaru 6 da 10, bi da bi. Mata na iya yin ƙwai tsakanin 70,000 zuwa 430,000, ya danganta da girmansu.
Kamar sauran uran birge, stan birgima mai ƙarfi ya shiga Kogin Danube don yin baƙuwar haihuwa a mafi yawan shekara, amma akwai lokuta biyu masu tsayi. Wannan aikin yana farawa ne a watan Maris a yanayin zafin jiki na ruwa 8 zuwa 11 ° C, ya kai ƙarfinsa a watan Afrilu kuma ya ci gaba har zuwa Mayu. Na biyu, mafi tsananin ƙaura yana farawa a watan Agusta kuma yana ci gaba har zuwa Oktoba. Wannan nau'ikan ya fi son mazaunan dumi fiye da sauran 'yan dambu na Danube, kuma kwararar da take yi yana faruwa ne a yanayin zafi sama da na wadanda ke yaduwa yayin da wasu halittun ke gudun hijira.
Abokan gaba na ƙarfin sturgeon
Hotuna: Sevryuga
Makiyan sevruga mutane ne. Balagagge (shekaru 6-10) yana sa su zama masu saukin kamun kifi. An kiyasta cewa yawansu a cikin manyan kwantena ya ragu da kashi 70% a cikin karnin da ya gabata. A lokacin shekarun 1990, kamun kifin ya karu matuka saboda kamun kifi ba bisa ka'ida ba. Farauta a cikin Bashin Volga-Caspian kawai an kiyasta ya ninka sau 10 zuwa 12 na iyakar doka.
Tsarin kogin kwarara da kamun kifi sune manyan dalilan da suka haifar da raguwar ƙwararrun mashahurin ƙarfe a karni na 20. Kawai a cikin tafkin Volga-Caspian, farautar farauta ta ninka sau 10-12 fiye da kamun da doka ta yi. Irin wannan yanayin yana faruwa akan Kogin Amur. Fiye da kamun kifi da farauta ya haifar da raguwa sosai a cikin jimlar kama doka a cikin duniya kuma musamman a cikin babban kwarin tauraron tauraron dan adam - Tekun Caspian.
Caviar ba kwayayen ƙwayayen sturgeon ne. Ga katako mai yawa, caviar, wanda ake kira "baƙar lu'u lu'u lu'u", shine abincin abinci. Wasu manyan nau'ikan sturgeon na kasuwanci guda uku sun samar da caviar ta musamman: beluga, sturgeon (sturgeon Russia) da stellate sturgeon (sturgeon star). Launi da girman ƙwai ya dogara da nau'in da matakin balagar ƙwai.
A yau Iran da Rasha sune manyan masu fitar da caviar, kimanin kashi 80% daga cikin nau'ikan nau'ikan ɓarna uku ne ke samar da su a cikin Tekun Caspian: sturgeon na Rasha (20% na kasuwa), sturlate sturgeon (28%) da Persia sturgeon (29%). Hakanan, matsalolin sturgeon sturgeon suna haifar da gurɓataccen ruwa, madatsun ruwa, ɓarna da ɓarkewar raƙuman ruwa da mahalli, waɗanda ke shafar hanyoyin ƙaura da wuraren ciyarwa da kiwo.
Yawan jama'a da matsayin jinsin
Photo: Stellate sturgeon kifi
Sevruga koyaushe baƙon mazaunin tsakiyar da Danube ne kuma yanzu an hallakar da shi daga Danube na sama da ɓangaren Hungary-Slovak na Middle Danube, tunda mutane ƙalilan ne suke gudanar da ayyukansu ta hanyar rufe ƙofofin Gateofar ƙarfe. Misali na ƙarshe da aka sani daga Slovak ɗin an ɗauke shi daga Komarno a ranar 20 ga Fabrairu, 1926, kuma na ƙarshe daga ɓangaren Hungary an yi rajista a cikin Mojács a 1965.
A cewar littafin Red Book, an tsoratar da fitaccen jarumin ne sakamakon bacewar sa da yawaitar kamun kifi, farauta, gurbatar ruwa, toshewa da lalata kogunan ruwa da muhalli. Koyaya, bisa la'akari da abubuwan yau da kullun akan Danube, yana da kusan ƙarewa. Yanzun haka na yawan jama'ar, wanda ya wuce kima ta hanyar yawaitar kamun kifi a baya, da kuma ainihin wurin da aka samar da isar. Ana buƙatar ƙarin bincike don gudanar da matakan kiyayewa ga wannan nau'in.
Gaskiya mai ban sha'awa: An sami gawawwakin mashahurai 55,000 da suka mutu a Tekun Azov a shekarar 1990 sakamakon gurbatar yanayi. Ragowar 87% na kamunnin kasuwancin duniya yana nuni da raguwar yawan jinsin.
Sturgeon na daji (sturgeon na kowa, sturgeon na Atlantic, tsuntsun Baltic, Baturke mai tsutsa Turai) ba a yi masa kifi a bakin tekun Finland ba tun daga 1930s. Mafi yawan nau'ikan da zasu iya shiga teku a cikin Finland sune tsayayyun tauraruwa. Hakanan zasu iya ɓacewa yayin da samfuran da aka adana suka mutu. Sturgeons suna rayuwa na dogon lokaci, saboda haka wannan aikin zai ɗauki ɗan lokaci.
Kariyar Sevruga
Hotuna: Sevruga daga littafin Red
Kusan dukkan nau'o'in sturgeon ana lasafta su a cikin haɗari. Namarsu da ƙwai masu daraja sosai (wanda aka fi sani da suna caviar) sun haifar da kamun kifi da raguwar yawan sturgeon. Bunkasar kogi da gurbatar yanayi suma sun taimaka wajen raguwar mutane. Baƙon Baturen Turai, wanda ya taɓa zama sananne a Jamus, ya ɓace kimanin shekaru 100 da suka gabata. Ana tsammanin jinsin zai koma rafuka a cikin Jamus ta hanyar ayyukan sake shigar da su.
Manufofin Duniya na Yaki da Karewar Sturgeons sun bayyana manyan kwatancen aiki don kiyaye sturgeon na shekaru 5 masu zuwa.
Dabarar tana mai da hankali kan:
- Yaki da wuce gona da iri;
- maidowar mazaunin rayuwa;
- kiyaye jariran sturgeon;
- samar da sadarwa.
WWF ta tsunduma cikin ayyukan kiyaye gida a yankuna da kasashe daban-daban. Ayyuka na musamman na ƙasa sun haɗa da ayyuka a cikin Austria (bayani a cikin Jamusanci), Bulgaria (Bulgarian), Netherlands (Dutch), Romania (Romania), Rasha da Kogin Amur (Rashanci) da Ukraine (Ukrainian).
Bugu da kari, WWF yana aiki a cikin:
- da Kogin Danube tare da wani shiri na musamman don magance yawan amfani da mashahuri a cikin Danube;
- maido da ƙarin kogunan ruwa na St John River a Kanada.
Stellate sturgeon Yana daya daga cikin mahimman halittu a duniya. Waɗannan ƙattai na ruwa na fuskantar barazanar da yawa don rayuwarsu. Duk da cewa sun rayu a doron duniya na miliyoyin shekaru, amma a halin yanzu fitattun mashahuran na fuskantar barazanar kamun kifi da tsangwama ga mazauninsu. Sevruga na cikin haɗari
Ranar bugawa: 08/16/2019
Ranar da aka sabunta: 16.08.2019 a 21:38
