<p>Macaronesian oceanic islands harbour the emblematic relict Canary Islands dragon tree (<i>D. draco</i> (L.) L. subsp. <i>draco</i>, Asparagaceae). Historical records suggest that its populations, nowadays restricted to Tenerife and Gran Canaria islands (Canaries) and Madeira Island, had a much wider geographic range in the past. In this study, we aimed at (i) testing whether current <i>D. draco</i> subsp. <i>draco</i> populations are relicts of a former wider distribution because of human impact, (ii) whether those populations are at risk with future climate change and (iii) targeting priority zones for in situ conservation face to global changes. We based our approach on the comparison between actual distribution, land use data and suitable area modelled <i>via</i> Environmental Niche Models (ENM) and projected under future climate change scenarios. ENM were calibrated at two different phylogenetic levels to account for taxonomic uncertainties. We found that: (i) The Canary Islands dragon tree populations occupy only 3–4% of their suitable area, reflecting their relict status due to past habitat alteration and overexploitation; (ii) Their response to future climate change varies depending on ENMs and climate change scenarios, but some projections suggest that climate may become unsuitable within their actual distribution range; (iii) Finally, we provide a map of zones to prioritize, specifically semi-natural areas predicted to remain suitable in the future, for in situ recovery operations.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Historical human impact on the endangered, relict and iconic Canary Islands dragon tree (Dracaena draco (L.) L.) and its uncertain fate in the face of climate change

  • Manuel Cartereau,
  • Frédéric Médail,
  • Alex Baumel,
  • Arnoldo Santos Guerra,
  • Petr Maděra,
  • Petr Vahalík,
  • Agathe Leriche

摘要

Macaronesian oceanic islands harbour the emblematic relict Canary Islands dragon tree (D. draco (L.) L. subsp. draco, Asparagaceae). Historical records suggest that its populations, nowadays restricted to Tenerife and Gran Canaria islands (Canaries) and Madeira Island, had a much wider geographic range in the past. In this study, we aimed at (i) testing whether current D. draco subsp. draco populations are relicts of a former wider distribution because of human impact, (ii) whether those populations are at risk with future climate change and (iii) targeting priority zones for in situ conservation face to global changes. We based our approach on the comparison between actual distribution, land use data and suitable area modelled via Environmental Niche Models (ENM) and projected under future climate change scenarios. ENM were calibrated at two different phylogenetic levels to account for taxonomic uncertainties. We found that: (i) The Canary Islands dragon tree populations occupy only 3–4% of their suitable area, reflecting their relict status due to past habitat alteration and overexploitation; (ii) Their response to future climate change varies depending on ENMs and climate change scenarios, but some projections suggest that climate may become unsuitable within their actual distribution range; (iii) Finally, we provide a map of zones to prioritize, specifically semi-natural areas predicted to remain suitable in the future, for in situ recovery operations.