Bakha wachinsalu (aka bakha wamutu wofiira waku America, Latin - Aythya americana) ndi wa banja la bakha, dongosolo la Anseriformes.
Kutuluka kwa Canvas kufalikira.
Bakha wapamadzi amapezeka m'mapiri a kumpoto kwa America, kuphatikiza United States kuchokera ku Colorado ndi Nevada, Northern British Columbia, Alberta, Saskatchewan, Manitoba, Yukon, ndi Central Alaska. M'zaka zaposachedwa, zafalikira kumpoto. Kuchuluka kwa nyengo yozizira kumachitika m'malo ochokera kunyanja ya Pacific Kumpoto chakumadzulo, kumwera kwa Great Lakes, komanso kumwera mpaka ku Florida, Mexico ndi California. Magulu akulu kwambiri achisanu amapezeka ku Lake St. Clair, Detroit River komanso kum'mawa kwa Lake Erie, Puget Sound, San Francisco Bay, Mississippi Delta, Chesapeake Bay, ndi Carrituck.
Imvani mawu akusambira.
Malo okhathamira.
Pakati pa nyengo yobereketsa, ma diving a canvas amapezeka m'malo okhala ndi madzi ang'onoang'ono, pomwe pano pang'onopang'ono. Amakhazikika m'malo okhala ndi nyanja zing'onozing'ono ndi mayiwe, m'madambo okhala ndiudzu wobiriwira monga mphalapala, mabango, ndi mabango. Nthawi yosamukira komanso m'nyengo yozizira, amakhala m'malo amadzi okhala ndi chakudya chambiri, m'kamwa mwa mitsinje, nyanja zazikulu, magombe am'mbali mwa nyanja, komanso madera amtsinje waukulu. Ali m'njira, amaima m'minda ndi m'mayiwe osefukira.
Zizindikiro zakunja kwazitsulo.
Ma diving a Canvas ndi "olemekezeka" enieni pakati pa abakha, adalandira tanthauzo loterolo chifukwa cha mawonekedwe awo okongola. Awa ndi abakha akulu kwambiri pamadzi. Amuna amakhala okulirapo pang'ono kuposa akazi, kuyambira 51 mpaka 56 cm kutalika. Amalemera magalamu 863 mpaka 1.589. Akazi omwe ali ndi kutalika kwa thupi kuyambira 48 mpaka 52 cm komanso kulemera kwa 908 mpaka 1.543 g.
Ma dothi a Canvas amasiyana ndi mitundu ina ya abakha osati kukula kwake kokha, komanso mawonekedwe awo ataliatali, osaya, mutu woboola pakati, womwe umakhala pakhosi lalitali. Amuna mu nthenga zoswana, omwe samasintha kwanthawi yayitali, amakhala ndi mutu ndi khosi lofiirira. Chifuwacho ndi chakuda, mapiko oyera, mbali ndi mimba. Nthenga zokwezeka pamwamba ndi mchira ndizakuda. Miyendo ndi yakuda imvi ndipo mlomowo ndi wakuda. Akazi ndi ofatsa, koma ofanana ndi amuna. Mutu ndi khosi zili zofiirira. Mapiko, mapiko, ndi mimba ndizoyera kapena zotuwa, pomwe mchira ndi chifuwa ndi zofiirira. Ma diving achichepere amakhala ndi nthenga zofiirira.
Kuberekanso kwa zadothi.
Kusambira pamadzi kumapanga awiriawiri panthawi yakusunthira masika ndipo nthawi zambiri amakhala ndi okwatirana nthawi yachilimwe, ngakhale nthawi zina amuna amakwatirana ndi akazi ena. Pakati pa chibwenzi, chachikazi chimazunguliridwa ndi amuna atatu mpaka asanu ndi atatu. Amakopa chachikazi, amatambasula khosi lawo, ndikuponya mutu wawo kutsogolo, kenako amatembenuzira mutu wawo kumbuyo.
Mkazi amasankha malo obisalira omwewo chaka chilichonse. Madera oyikira mazira adatsimikizika kumapeto kwa Epulo, koma nsonga yayikulu imapezeka mu Meyi - Juni. Mbalame ziwiri zimakhala ndi ana amodzi pachaka, ngakhale abakha amaberekanso ngati ana oyamba awonongedwa. Zisa zimamangidwa mu zomera zomwe zikungotuluka pamwamba pamadzi, ngakhale nthawi zina zimamanga zisa kumtunda pafupi ndi madzi. Akazi amaikira mazira 5 mpaka 11 osalala, elliptical, obiriwira.
Mu clutch, kutengera dera, pali mazira 6 mpaka 8 pachisa chilichonse, koma nthawi zina makamaka chifukwa cha parasitism ya chisa. Makulitsidwe amatenga masiku 24 mpaka 29. Achinyamata osiyanasiyana amatha kusambira ndikupeza chakudya nthawi yomweyo. Mkazi akaona kuti nyama yolusa ili pafupi ndi ana, amasambira mwakachetechete kuti asokoneze chidwi chake. Bakha amachenjeza anapiye aang'ono ndi mawu kuti azikhala ndi nthawi yobisala m'nkhalango zowirira. Kunja kwa nyengo yoswana, mbalame zimapanga magulu akuluakulu, omwe amathandiza kupewa zowononga. Komabe, mpaka 60% ya anapiye amafa.
Anapiye amakwaniritsa zaka 56 mpaka 68 zakubadwa.
Akazi amamanga zisa kuchokera ku zomera ndi nthenga. Amuna amateteza mwamphamvu malo awo ndi zisa zawo, makamaka sabata yoyamba mutangoyamba kumene. Kenako amakhala nthawi yocheperako pafupi ndi chisa. Zazikazi zimachoka pachisa pamodzi ndi anawo pasanathe maola 24 kuchokera anapiyewo atatuluka ndikupita kumalo osungira okulirapo okhala ndi masamba ochuluka omwe akutuluka.
Amakhala ndi ankhandwe mpaka atasamuka ndikuwateteza kwa adani. Ma diving Canvas amakhala m'malo awo achilengedwe kwa zaka zoposa 22 ndi miyezi 7. Chakumapeto kwa Ogasiti kapena koyambirira kwa Seputembala, abakha achichepere amapanga magulu kuti akonzekere kusamuka. Zimaswana chaka chamawa.
Kupulumuka kwapachaka kwamadzimadzi achikulire kukuyerekeza 82% ya amuna ndi 69% ya akazi. Nthawi zambiri, abakha amaphedwa ndi kusaka, kugundana, poizoni wa tizilombo komanso nthawi yozizira.
Makhalidwe amachitidwe olowera pamadzi.
Ma diving a Canvas amakhala akugwira masana. Ndi mbalame zomwe zimakonda kucheza ndipo zimasuntha nyengo yakwana zitaswana. Amayendetsa gulu laulere lopangidwa ndi V mwachangu mpaka 90 km / h. Asananyamuke, amafalikira pamadzi. Abakhawa ndi osambira othandiza komanso amphamvu, miyendo yawo ili kumbuyo kwa thupi. Amakhala mpaka 20% ya nthawi yawo pamadzi ndikusambira pansi kupitirira mamita 9. Amakhala pansi pamadzi kwa masekondi 10 mpaka 20. Malo obereketsa amasintha kukula kwake panthawi yoswana. Malo obereketsawa amakhala mahekitala 73 asanaikidwe mazira, kenako amatambalala mpaka mahekitala 150 asanaikidwe, kenako amachepera mpaka mahekitala 25 mazira atayikidwa kale.
Kudyetsa pamadontho.
Ma diving a Canvas ndi mbalame zodabwitsa. M'nyengo yozizira komanso yosamuka, amadya zomera zam'madzi kuphatikiza masamba, mizu, ma tubers ndi ma rhizomes. Amadya ma gastropods ang'onoang'ono komanso ma bivalve molluscs nthawi. Nthawi yoswana, amadya nkhono, mphutsi za caddis ndi nymphs za agulugufe ndi mayflies, mphutsi za udzudzu - mabelu. Kunja kwa nyengo yoswana, ma diving amalowa m'magulu a mbalame mpaka 1000 makamaka m'mawa ndi madzulo. Abakha awa osambira pamadzi amatenga chakudya posambira pamadzi kapena kugwira nyama yomwe ili pamwamba pamadzi kapena mlengalenga.
Malo osungira zadothi.
Ma diving Canvas ndiotetezedwa, otetezedwa ngati mitundu yosamukira ku United States, Mexico ndi Canada. Mitunduyi sikhala ndi ziwopsezo zazikulu pamanambala ake. Komabe, kuchuluka kwa mbalame kumachepa chifukwa chowombera, kuwononga malo, kuwonongeka kwa chilengedwe komanso kuwombana ndi magalimoto kapena zinthu zoyimirira.
Kusaka nthawi yophukira kumakhala ndi mphamvu yayikulu pakusamuka kwa mbalame. Mu 1999, pafupifupi 87,000 anaphedwa ku United States. Ma diving a Canvas amathanso kutenga poizoni omwe amapezeka mumadontho. Izi ndizowona makamaka m'malo omwe ali ndi mafakitale ambiri monga Detroit River. Mitundu Yosasamala Yoyesedwa ndi IUCN.
