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Bucardo Pyrenean Ibex

Tikėtina, kad pirmasis 2000-ųjų išnykimo įvykis Europoje, liūdna Pirėnų ožių (Capra pyrenaica pyrenaica) istorija yra galingas nuolat didėjančio rūšių nykimo visame pasaulyje dėl priežasčių, susijusių su žmogaus veikla, pavyzdys. Tačiau tai gali suteikti mums vertingos informacijos apie tai, ką reikėtų daryti (ar vengti), kad šis išnykimo sūkurys būtų sustabdytas.

Laña Paskutinis išgyvenęs Pirėnų ožkas

Laña, paskutinis išgyvenęs Pirėnų ožiukas, 2012 m. lapkričio 6 d. grįžo į Torla-Ordesą kaip žirgas gyvūnas po prieštaringai vertinamo bandymo klonuoti. Jos oda dabar eksponuojama Ordesos ir Monte Perdido nacionalinio parko lankytojų centre. Kreditas: Manolo Grasa

Šio Iberijos kalkių porūšio paplitimas apsiribojo Prancūzijos ir Ispanijos Pirėnų kalnais. Pirmasis jo paminėjimas oficialiame rašytiniame dokumente, datuojamas 1767 m., jau minimas kaip itin retas. Kaip ir daugelis kitų kalnų ožkų, ji buvo beveik sumedžiota iki išnykimo, kol 1913 m. buvo uždrausta žudyti. Nei nacionalinio parko įsteigimas (Ordesa ir Monte Perdido), nei išsaugojimo projektas, finansuojamas iš Europos LIFE programos, negalėjo sustabdyti Pirėnų nykimo. Ibex galiausiai oficialiai patvirtintas 2000 m. sausio 6 d.

Tačiau šio charizmatiško gyvūno istorija tuo nesibaigė – prieštaringai vertinama klonavimo programa buvo pradėta akimirksniu be jokio mokslinio susitarimo ar regioninių aplinkosaugos nevyriausybinių organizacijų paramos, teigdama, kad išnykimas įmanomas net ir nesant tolesnių veiksmų.[{“ attribute=““>DNA studies.

To find out more about the drivers of its extinction, an international team composed of 7 nationalities built a database of all known museum specimens and reconstructed the demographic history of the Pyrenean Ibex based on DNA evidence. Their research is published in the open-access, peer-reviewed journal Zoosystematics and Evolution.

The research found that after a population expansion between 14,000 and 29,000 years ago (which is quite recent from a genetic point of view), a significant loss of genetic diversity followed between approximately 15,000 and 7,500 years BP, and continued until present. By that time, the Pyrenean Ibex also lived outside the Pyrenean mountain chain, but, gradually, its distribution was reduced to only one valley in the Ordesa National Park in the Spanish Pyrenees.

Ordesa Valley Hunting Party

The adventures of the British hunter E.N. Buxton were published in 1893. This engraving represents a hunting party in the Ordesa Valley (Spanish Pyrenees).

Written sources confirm hunting of the Pyrenean Ibex from as early as the 14th century, and during the 19th and 20th century it became a common target for trophy hunters. Undoubtedly, hunting played an important role in reducing its population numbers and distribution area, but it is not possible — with the information currently available — to pinpoint it as the straw that broke the camel’s back. Infectious diseases that originate from livestock (for instance, those caused by the bluetongue virus, BTV, and sarcopses) are capable of decimating other subspecies of Iberian Ibex in extremely short periods of time.

While the relative contribution of various factors remains largely unknown, it seems that hunting and diseases transmitted from other animals have been effective in drastically reducing the number of Pyrenean ibexes over the last two centuries, because they were acting on an already genetically weakened population. This low genetic diversity, combined with inbreeding depression and reduced fertility, brought the population beyond the minimum viable size — from that point onwards, extinction was inevitable.

Bucardo Pyrenean Ibex

Only the French mountaineer and photographer Bernhard Clos managed to take a series of good photos of the Bucardo, as the Pyrenean Ibex is called on the Spanish side. Credit: Bernhard Clos

This case study shows the importance of historical biological collections for genetic analyses of extinct species. A privately owned 140-year-old trophy preserved in Pau, France, was genotyped as part of this research, showing that private individuals may possess material of high value. As there is little knowledge of such resources, the authors call for the creation of an online public database of private collections hosting biological material for the benefit of biodiversity studies.

Reference: “Demography reveals populational expansion of a recently extinct Iberian ungulate” by Giovanni Forcina, Kees Woutersen, Santiago Sánchez-Ramírez, Samer Angelone, Jean P. Crampe, Jesus M. Pérez, Paulino Fandos, José Enrique Granados and Michael J. Jowers, 1 April 2021, Zoosystematics and Evolution.
DOI: 10.3897/zse.97.61854

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