Mitochondrial D-loop Sequence Variability in Three Native Insular Griffon Vulture (Gyps fulvus) Populations from the Mediterranean Basin.

Paolo Mereu,Gian Nicola Frongia,Valentina Satta,Monica Pirastru,Laura Manca,Nicolaos Kassinis,Giovanni Giuseppe Leoni,Minas Papadopoulos,Salvatore Naitana,Stavros Xirouchakis,Eleftherios Hadjisterkotis

doi:10.1155/2019/2073919

Abstract

The islands of Sardinia, Crete, and Cyprus are hosting the last native insular griffon populations in the Mediterranean basin. Their states have been evaluated from “vulnerable” to “critically endangered”. The sequence analysis of molecular markers, particularly the mtDNA D-loop region, provides useful information in studying the evolution of closely related taxa and the conservation of endangered species. Therefore, a study of D-loop region sequence was carried out to estimate the genetic diversity and phylogenetic relationship within and among these three populations. Among 84 griffon specimens (44 Sardinian, 33 Cretan, and 7 Cypriot), we detected four haplotypes including a novel haplotype (HPT-D) that was exclusively found in the Cretan population with a frequency of 6.1%. When considered as a unique population, haplotype diversity (Hd) and nucleotide diversity (π) were high at 0.474 and 0.00176, respectively. A similar level of Hd and π was found in Sardinian and Cretan populations, both showing three haplotypes. The different haplotype frequencies and exclusivity detected were in accordance with the limited matrilineal gene flow (FST = 0.07097), probably related to the species reluctance to fly over sea masses. The genetic variability we observe today would therefore be the result of an evolutionary process strongly influenced by isolation leading to the appearance of island variants which deserve to be protected. Furthermore, since nesting sites and food availability are essential elements for colony settlement, we may infer that the island's colonization began when the first domestic animals were transferred by humans during the Neolithic. In conclusion, our research presents a first contribution to the genetic characterization of the griffon vulture populations in the Mediterranean islands of Sardinia, Crete and Cyprus and lays the foundation for conservation and restocking programs.

Highlights

Introduction e European gri on (Accipitridae; Aegypetinae; Gyps; G. fulvus) is a vulture species widely distributed from the Mediterranean Basin in the west to the Indian subcontinent in the east. e species breeding range extends over Europe to the Middle East and North Africa including some island populations in the Mediterranean i.e., Majorca, Sardinia, Crete, Cyprus, and the Croatian islets of Cres, Krk, Prvić, and Plavnik. e European population is currently estimated at 32,400-34,400 pairs with the bulk of it residing on the Iberian Peninsula (BirdLife International 2017)
Based on FST classes provided by Hartl and Clark [31], we found a moderate level (FST = 0.07097) of genetic differentiation among the three gri on populations investigated, according to a limited matrilineal gene ow probably caused by the species reluctance to y over sea masses or cross long sea stretches and it is con rmed by the analysis on haplotypes frequencies and exclusivity (HPT-D in Crete, HPT-B in Sardinia). is evidence is consistent with Le Gouar et al [15] which detected high immigration rate in all Continental Europe gri on population and signs of recent isolation due to limited immigration in the Croatian population
We could suppose that a er the first colonization events the Cretan and Sardinian populations remained isolated for a long time during which they maintained genetic variability while the Cypriot colony underwent a drastic bottleneck which only the HPT A survived

Summary

Introduction

Gri ons breed colonially on cli s and rocky outcrops and feed communally almost exclusively on the carrion of medium-sized livestock and wildlife animals [1, 2, 3] Due to their population size and feeding habits, they play a crucial role in Mediterranean ecosystems. Broad wings and low wing-loading and low aspect ratio enable gri ons to exploit e ectively thermals, but, in any case, soaring ight that depends on thermals determines to a large extent their dispersal ability and migratory behaviour. They concentrate in speci c locations such as peninsulas and land straits (e.g. Gibraltar, Suez) avoiding to y over water. In comparison to adults, juvenile griffons exhibit inferior thermal soaring performance in their rst two months a er edging due to the inexperience in thermal selection and centring, and interthermal gliding soaring [14]

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Conclusion