Doki na teku na Knysna
| Doki na teku na Knysna | |
|---|---|
 | |
| Conservation status | |
|
Invalid status IUCN3.1 :
| |
| Scientific classification | |
| Kingdom | Animalia |
| Phylum | Chordata (mul)  |
| Class | Actinopteri (mul) |
| Order | Syngnathiformes (mul) |
| Dangi | Syngnathidae (mul) |
| Genus | Hippocampus (mul)
|
| jinsi | Hippocampus capensis Boulenger, 1900
|
Knysna / ˈnaɪznə / seahorse ko Cape seahorse ( Hippocampus capensis ) nau'in kifi ne a cikin dangin Syngnathidae . Yana da yawa a gabar tekun kudu na Afirka ta Kudu, inda aka samo shi a cikin wuraren zama na ruwa guda uku kawai: bakin kogin Keurbooms a Plettenberg Bay, tafkin Knysna, da kuma ɓangaren estuarine na tsarin Swartvlei a Sedgefield . Iyakantaccen kewayon wannan dokin teku yana sanya shi cikin babban haɗarin ɓacewa.
Bayani
[gyara sashe | gyara masomin]
Dokin teku na Knysna ƙarami ne, mai laushi, wanda tsayinsa ya kai santimita 12. Launi yana da tasiri sosai daga yanayin da ke kewaye da shi da kuma yanayin wani mutum. Ya bambanta daga kore mai haske zuwa launin ruwan kasa (sau da yawa yana da tabo masu duhu) zuwa baƙi mai launin shuɗi. Jikin yana cikin jerin zoben ƙashi, hancin yana da ɗan gajere, kuma wuyansa yana da lanƙwasa mai santsi ba tare da kambi ba. Wutsiyar tana da ƙarfi kuma ana amfani da ita don kama abokin tarayya yayin soyayya ko kuma don ɗaure kifin a kan abin da aka yi amfani da shi.
Dokin teku na Knysna yana faruwa ne galibi a yankunan da ke da rufin ciyayi mai yawa (aƙalla kashi 75%), kuma yana da alaƙa da shuke-shuke guda biyar masu rinjaye a cikin ruwa: Zostera capensis, Caulerpa filiformis, Codium extricatum, Halophila ovalis da Ruppia cirrhosa . [1] Duk da cewa Keurbooms da Swartvlei estuaries suna da murfin shuke-shuke masu yawa, wuraren da aka shuka sun kai kusan kashi 11% ne kawai na tafkin Knysna. [1] Saboda haka, manyan wurare na zama a cikin wannan tsarin ba za su dace da H. capensis ba.
Kifin ya dace da yanayin estuarine kuma yana iya jure wa yanayi daban-daban na muhalli, kamar gishirin da ke tsakanin 1-59 ‰. [2]
Kiwo yana faruwa ne a lokacin bazara na Ostiraliya lokacin da yanayin zafi na ruwa ya kusan digiri 20 °C. Balagaggen jima'i yana kaiwa ga kimanin shekara ɗaya a shekara 65. tsawon mm na yau da kullun. [2]
Tsarin yawan jama'a
[gyara sashe | gyara masomin]Bayanan kwayoyin halitta daga yankin kula da mitochondrial sun nuna cewa, duk da cewa kowace al'umma uku ta Hippocampus capensis tana da haɗin haplotypes na musamman, babu wani tallafi ga hasashen cewa kowanne yana wakiltar wani nau'in halitta daban-daban. [3] An tabbatar da wannan binciken kwanan nan ta hanyar ƙarin bayanai masu canzawa na microsatellite . [4] Don haka babu wani dalili mai ƙarfi da zai sa a hana mutane su canza tsakanin magudanar ruwa, idan wannan ya zama dole. Ƙananan bambancin kwayoyin halitta a cikin magudanar ruwa ta Swartvlei yana nuna cewa wannan al'umma ta ware wani ɓangare daga sauran al'ummomi biyu. [4]
Girman yawan jama'a
[gyara sashe | gyara masomin]Bayanan ƙidayar jama'a daga 2002 da 2003 (WWF-SA) sun nuna cewa girman yawan jama'ar Hippocampus capensis a cikin Keurbooms da Swartvlei estuaries a wasu lokutan na iya wuce na babban tafkin Knysna. [5] Duk da haka, suna canzawa sosai. A cikin kogin Keurbooms, lokacin kwararar kogi mai ƙarfi na iya haifar da ɓacewar nau'in na ɗan lokaci, yana nuna cewa wannan kogin ba shi da yawan dokin teku na dindindin kuma yana ba da wurin zama kawai lokacin da yanayi ya yi kyau. [5] An sake gano Hippocampus capensis a cikin kogin a lokacin binciken da Gidauniyar ORCA ta gudanar kwanan nan, amma an kuma gano cewa wannan yawan jama'a ya ragu sakamakon ambaliyar ruwa a lokacin 2007 da 2011.
Manazarta
[gyara sashe | gyara masomin]- 1 2 Teske, P.R.; Lockyear, J.F.; Hecht, T.; Kaiser H. (2007). "Does the endangered Knysna seahorse, Hippocampus capensis, have a preference for aquatic vegetation type, cover or height?" (PDF). African Zoology. 42: 23–30. doi:10.3377/1562-7020(2007)42[23:dteksh]2.0.co;2.[permanent dead link]
- 1 2 Whitfield, A.K. (1995). "Threatened fishes of the world: Hippocampus capensis Boulenger, 1900 (Syngnathidae)". Environmental Biology of Fishes. 44 (4): 362. Bibcode:1995EnvBF..44..362W. doi:10.1007/bf00008251. S2CID 38433225.
- ↑ Teske, P.R.; Cherry, M.I.; Matthee, C.A. (2003). "Population genetics of the endangered Knysna seahorse, Hippocampus capensis" (PDF). Molecular Ecology. 12 (7): 1703–1715. Bibcode:2003MolEc..12.1703T. doi:10.1046/j.1365-294x.2003.01852.x. PMID 12803625. S2CID 37074742.[permanent dead link]
- 1 2 Mkare, T.K.; van Vuuren, B.J.; Teske, P.R. (2017). "Conservation implications of significant population differentiation in an endangered estuarine seahorse". Biodiversity and Conservation. 26 (6): 1275–1293. Bibcode:2017BiCon..26.1275M. doi:10.1007/s10531-017-1300-5. S2CID 24820130.
- 1 2 Lockyear, J.L.; Hecht, T.; Kaiser, H. & Teske, R.P. (2006). "The distribution and abundance of the endangered Knysna seahorse Hippocampus capensis (Pisces: Syngnathidae) in South African estuaries" (PDF). African Journal of Aquatic Science. 31 (2): 275–283. Bibcode:2006AfJAS..31..275L. doi:10.2989/16085910609503897. S2CID 84638117.[permanent dead link]