{"id":7338,"date":"2026-01-31T06:03:59","date_gmt":"2026-01-31T04:03:59","guid":{"rendered":"https:\/\/www.schooler.org.ua\/uk-uasvalbardski-bili-vedmedi-ne-vidpovidajut-ochikuvannjam-naprochud\/"},"modified":"2026-01-31T06:03:59","modified_gmt":"2026-01-31T04:03:59","slug":"uk-uasvalbardski-bili-vedmedi-ne-vidpovidajut-ochikuvannjam-naprochud","status":"publish","type":"post","link":"https:\/\/www.schooler.org.ua\/cs\/uk-uasvalbardski-bili-vedmedi-ne-vidpovidajut-ochikuvannjam-naprochud\/","title":{"rendered":"Svalbard Polar Bears Defy Expectations: P\u0159ekvapiv\u011b stabiln\u00ed populace"},"content":{"rendered":"

Navzdory alarmuj\u00edc\u00edm glob\u00e1ln\u00edm trend\u016fm v \u00fabytku ledn\u00edch medv\u011bd\u016f populace v norsk\u00e9m souostrov\u00ed Svalbard nejen p\u0159e\u017e\u00edvaj\u00ed, ale zlep\u0161uj\u00ed se<\/em> v rychle se m\u011bn\u00edc\u00edch podm\u00ednk\u00e1ch. V\u00fdsledky, ned\u00e1vno zve\u0159ejn\u011bn\u00e9 ve Scientific Reports<\/em>, zd\u016fraz\u0148uj\u00ed jedine\u010dnou situaci, ve kter\u00e9 medv\u011bdi udr\u017euj\u00ed, a dokonce zvy\u0161uj\u00ed z\u00e1soby tuku, navzdory zna\u010dn\u00e9mu \u00fabytku mo\u0159sk\u00e9ho ledu. To vyvol\u00e1v\u00e1 kritick\u00e9 ot\u00e1zky o tom, jak se n\u011bkter\u00e9 populace mohou p\u0159izp\u016fsobit a co to znamen\u00e1 pro budoucnost tohoto ikonick\u00e9ho druhu. <\/p>\n

\u0160picbersk\u00fd paradox<\/h3>\n

Svalbard, kter\u00fd se nach\u00e1z\u00ed mezi Norskem a severn\u00edm p\u00f3lem, je vzd\u00e1len\u00e1 oblast, kter\u00e1 \u010del\u00ed zrychluj\u00edc\u00edmu se arktick\u00e9mu oteplov\u00e1n\u00ed. Teploty v okoln\u00edm Barentsov\u011b mo\u0159i vzrostly a\u017e o 2 \u00b0C (3,6 \u00b0F) za desetilet\u00ed<\/em> od roku 1980. Na rozd\u00edl od jin\u00fdch oblast\u00ed, kde po\u010dty ledn\u00edch medv\u011bd\u016f prudce klesaj\u00ed, z\u016fst\u00e1v\u00e1 populace \u0160picberk\u016f, odhadovan\u00e1 na p\u0159ibli\u017en\u011b 3 000, pozoruhodn\u011b stabiln\u00ed. Tato stabilita je obzvl\u00e1\u0161t\u011b pozoruhodn\u00e1 vzhledem k tomu, \u017ee celosv\u011btov\u011b \u010del\u00ed ledn\u00ed medv\u011bdi p\u0159edpokl\u00e1dan\u00e9mu riziku vyhynut\u00ed ze dvou t\u0159etin do roku 2050 v d\u016fsledku ztr\u00e1ty p\u0159irozen\u00e9ho prost\u0159ed\u00ed. <\/p>\n

Co definuje udr\u017eitelnost?<\/h3>\n

V\u011bdci z Norsk\u00e9ho pol\u00e1rn\u00edho institutu analyzovali t\u00e9m\u011b\u0159 t\u0159i desetilet\u00ed dat (1992\u20132019) o 770 dosp\u011bl\u00fdch ledn\u00edch medv\u011bdech a hodnotili jejich index t\u011blesn\u00e9 hmotnosti (BMI) spolu s po\u010dtem dn\u016f bez ledu. Data odhalila kontraintuitivn\u00ed trend: jak ub\u00fdvalo mo\u0159sk\u00e9ho ledu, z\u00e1soby tuku u medv\u011bd\u016f se po roce 2000 zv\u011bt\u0161ily<\/em>. <\/p>\n

Zd\u00e1 se, \u017ee tato odolnost je zp\u016fsobena n\u011bkolika faktory jedine\u010dn\u00fdmi pro Svalbard:<\/p>\n

    \n
  • Nedostatek loveck\u00e9ho tlaku:<\/strong> Ledn\u00ed medv\u011bdi jsou v t\u00e9to oblasti chr\u00e1n\u011bni p\u0159ed lovem od roku 1973, co\u017e eliminuje velkou hrozbu. <\/li>\n
  • Omezen\u00e1 konkurence:<\/strong> Medv\u011bdi \u010del\u00ed minim\u00e1ln\u00ed konkurenci ostatn\u00edch suchozemsk\u00fdch pred\u00e1tor\u016f. <\/li>\n
  • Alternativn\u00ed zdroje potravy:<\/strong> Svalbard je domovem prosperuj\u00edc\u00edch populac\u00ed sob\u016f a mro\u017e\u016f, kter\u00e9 poskytuj\u00ed alternativn\u00ed ko\u0159ist, kdy\u017e je tuleni nedostatek. <\/li>\n
  • Koncentrovan\u00e9 populace tule\u0148\u016f:<\/strong> Ub\u00fdvaj\u00edc\u00ed mo\u0159sk\u00fd led m\u016f\u017ee vytla\u010dit tule\u0148e krou\u017ekovit\u00e9ho do men\u0161\u00edch oblast\u00ed, co\u017e medv\u011bd\u016fm usnadn\u00ed lov. <\/li>\n<\/ul>\n

    Limity adaptace<\/h3>\n

    P\u0159esto\u017ee se medv\u011bd\u016fm Svalbard\u016fm v sou\u010dasnosti da\u0159\u00ed l\u00e9pe, ne\u017e se o\u010dek\u00e1valo, v\u00fdzkumn\u00edci varuj\u00ed, \u017ee tato odolnost m\u00e1 pravd\u011bpodobn\u011b sv\u00e9 meze. Dal\u0161\u00ed \u00fabytek mo\u0159sk\u00e9ho ledu by mohl p\u0159inutit medv\u011bdy cestovat na dlouh\u00e9 vzd\u00e1lenosti, aby dos\u00e1hli lovi\u0161\u0165, co\u017e by zv\u00fd\u0161ilo v\u00fddaje na energii a potenci\u00e1ln\u011b by zvr\u00e1tilo sou\u010dasn\u00e9 zisky. Tento jev ji\u017e byl pozorov\u00e1n u jin\u00fdch bojuj\u00edc\u00edch populac\u00ed ledn\u00edch medv\u011bd\u016f. <\/p>\n

    \n

    \u201eAbychom pochopili, jak se populace vyrovn\u00e1v\u00e1, je t\u0159eba ji prostudovat,\u201c \u0159\u00edk\u00e1 ekolog ledn\u00edch medv\u011bd\u016f Jon Ars. “Nem\u016f\u017eete extrapolovat z\u00e1v\u011bry z jin\u00fdch region\u016f, kde m\u016f\u017ee b\u00fdt situace \u00fapln\u011b jin\u00e1.” <\/p>\n<\/blockquote>\n

    V\u011bt\u0161\u00ed obr\u00e1zek<\/h3>\n

    P\u0159\u00edpad Svalbard ukazuje, \u017ee adaptace ledn\u00edch medv\u011bd\u016f je heterogenn\u00ed. N\u011bkter\u00e9 populace mohou pod tlakem vykazovat neo\u010dek\u00e1vanou odolnost, zat\u00edmco jin\u00e9 budou nad\u00e1le klesat. Dlouhodob\u00e9 sledov\u00e1n\u00ed je z\u00e1sadn\u00ed pro pochopen\u00ed t\u011bchto rozd\u00edl\u016f a p\u0159edpov\u00edd\u00e1n\u00ed budoucnosti tohoto druhu v rychle se m\u011bn\u00edc\u00ed Arktid\u011b. <\/p>\n

    Tato zji\u0161t\u011bn\u00ed podtrhuj\u00ed nal\u00e9havost \u0159e\u0161en\u00ed zm\u011bny klimatu, i kdy\u017e odhaluj\u00ed slo\u017eit\u00e9 a \u010dasto p\u0159ekvapiv\u00e9 zp\u016fsoby, kter\u00fdmi m\u016f\u017ee divok\u00e1 zv\u011b\u0159 reagovat na environment\u00e1ln\u00ed stres.<\/p>\n","protected":false},"excerpt":{"rendered":"

    Navzdory alarmuj\u00edc\u00edm glob\u00e1ln\u00edm trend\u016fm v \u00fabytku ledn\u00edch medv\u011bd\u016f populace v norsk\u00e9m souostrov\u00ed Svalbard nejen p\u0159e\u017e\u00edvaj\u00ed, ale zlep\u0161uj\u00ed se v rychle se m\u011bn\u00edc\u00edch podm\u00ednk\u00e1ch. V\u00fdsledky, ned\u00e1vno zve\u0159ejn\u011bn\u00e9 ve Scientific Reports, zd\u016fraz\u0148uj\u00ed jedine\u010dnou situaci, ve kter\u00e9 medv\u011bdi udr\u017euj\u00ed, a dokonce zvy\u0161uj\u00ed z\u00e1soby tuku, navzdory zna\u010dn\u00e9mu \u00fabytku mo\u0159sk\u00e9ho ledu. To vyvol\u00e1v\u00e1 kritick\u00e9 ot\u00e1zky o tom, jak se n\u011bkter\u00e9 […]<\/p>\n","protected":false},"author":1,"featured_media":7337,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"tdm_status":"","tdm_grid_status":""},"categories":[1],"tags":[],"wpm_language_slugs":[],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/posts\/7338"}],"collection":[{"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/comments?post=7338"}],"version-history":[{"count":0,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/posts\/7338\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/media\/7337"}],"wp:attachment":[{"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/media?parent=7338"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/categories?post=7338"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/tags?post=7338"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}