Predicting spatial patterns of Cuculus canorus under climate change in Türkiye

Öz

Climate change is reshaping species distributions worldwide, with migratory birds representing one of the most vulnerable groups in this process. The Common Cuckoo (Cuculus canorus), a species of high ecological importance, is widely distributed across Eurasia but is increasingly threatened by habitat loss and climatic shifts. In this study, we applied the MaxEnt algorithm to predict the current and future distribution of the cuckoo in Türkiye under present and projected climate conditions. In addition to bioclimatic predictors, topographic variables were included in the modeling framework. Pearson correlation analysis was used to minimize multicollinearity, and variable contributions were evaluated through jackknife tests. The model performed strongly (AUC = 0.81), and response curves indicated that temperature and precipitation were the primary determinants of habitat suitability. Projections for the year 2100 under SSP3-7.0 and SSP5-8.5 scenarios revealed substantial contractions of suitable areas, with no new habitat gains. The extent of climatically suitable habitat is predicted to decline from 631001 km² at present to 285035 km² under SSP3-7.0 and to 151822 km² under SSP5-8.5. Losses were most pronounced at lower elevations, consistent with thermophilization and upslope range shifts. The results highlight potential refugia as critical targets for conservation, while also emphasizing the importance of considering host species distribution, habitat connectivity, and migratory stopover sites in management strategies. This study provides the first comprehensive, spatially explicit projection of cuckoo distribution in Türkiye, offering novel insights into the species’ vulnerability to climate change.

Anahtar Kelimeler

• Climate scenarios
• Common cuckoo
• Habitat suitability
• MaxEnt
• Species distribution modeling

İklim değişikliğine bağlı olarak Cuculus canorus türünün Türkiye’deki mekansal dağılımının tahmin edilmesi

Öz

İklim değişikliği dünya genelinde türlerin dağılımını yeniden şekillendirmektedir. Göçmen kuşlar bu değişim sürecinin en hassas gruplardan birini oluşturmaktadır. Yüksek ekolojik öneme sahip bir tür olan guguk kuşu (Cuculus canorus), Avrasya genelinde yayılış göstermekte ancak habitat kaybı ve iklimsel değişimlerden giderek daha fazla etkilenmektedir. Bu çalışmada, Türkiye’deki guguk kuşu dağılımını mevcut ve gelecekteki iklim koşulları altında tahmin etmek amacıyla MaxEnt algoritması uygulanmıştır. Modellemede biyoklimatik değişkenlere ek olarak topoğrafik değişkenler kullanılmıştır. Değişken seçiminde çoklu bağlantıyı azaltmak için Pearson korelasyon analizi uygulanmış, değişken katkıları ise jackknife testleriyle değerlendirilmiştir. Model güçlü bir performans sergilemiştir (AUC = 0.81) ve tepki eğrileri sıcaklık ve yağış değişkenlerinin habitat uygunluğunda belirleyici olduğunu göstermiştir. 2100 yılı için SSP3-7.0 ve SSP5-8.5 senaryoları altında yapılan projeksiyonlar, yeni kazanım olmaksızın uygun alanlarda ciddi daralmalar öngörmektedir. Mevcut durumda 631001 km² olan uygun habitat alanı, SSP3-7.0 senaryosunda 285035 km²’ye, SSP5-8.5 senaryosunda ise 151822 km²’ye düşmektedir. Bu kayıplar özellikle düşük rakımlarda yoğunlaşmış olup, termofilizasyon ve yükseltiye doğru dağılım kaymaları ile uyumludur. Bulgular, iklim değişikliğine karşı görece stabil kalabilecek refugia alanlarının koruma açısından kritik olduğunu ortaya koymakta; aynı zamanda konak türlerin dağılımı, habitat bağlantısı ve göç sırasında kullanılan konaklama alanlarının da dikkate alınması gerektiğini vurgulamaktadır. Bu çalışma, Türkiye’de guguk kuşunun dağılımına yönelik ilk kapsamlı ve mekânsal projeksiyonu sunarak, türün iklim değişikliğine karşı kırılganlığına dair yeni bilgiler sağlamaktadır.

Anahtar Kelimeler

• İklim senaryoları
• Guguk kuşu
• Habitat uygunluğu
• MaxEnt
• Tür dağılım modellemesi

Kaynakça

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