Past volcanic activity predisposes an endemic threatened seabird to negative anthropogenic impacts

Humans are regularly cited as the main driver of current biodiversity extinction, but the impact of historic volcanic activity is often overlooked. Pre-human evidence of wildlife abundance and diversity are essential for disentangling anthropogenic impacts from natural events. Réunion Island, with its intense and well-documented volcanic activity, endemic biodiversity, long history of isolation and recent human colonization, provides an opportunity to disentangle these processes. We track past demographic changes of a critically endangered seabird, the Mascarene petrel Pseudobulweria aterrima, using genome-wide SNPs. Coalescent modeling suggested that a large ancestral population underwent a substantial population decline in two distinct phases, ca. 125,000 and 37,000 years ago, coinciding with periods of major eruptions of Piton des Neiges. Subsequently, the ancestral population was fragmented into the two known colonies, ca. 1,500 years ago, following eruptions of Piton de la Fournais..., Single Nucleotide Polymorphism (SNP) genotyping was carried out by Diversity Arrays Technology (DarT Pty Ltd, Canberra) using the DArTseq protocol. DArT library was prepared using DNA from 93 birds and the restriction enzymes PstI and SphI.  Loci were aligned to the genome assembly of Calonectris borealis (family Procellariidae; GCA_013401115.1).
The raw DArTseq data (67,095 SNPs) was filtered by the authors using the dartR v 2.1.4 R package (see manuscript for details). Four genomic datasets (dataset 1 – dataset 4) were generated and used for the downstream analyses (See Text S1 and Fig. S8 for details).
Specimen metadata was collated during fieldwork., , This README file was generated by Helena Teixeira.

**GENERAL INFORMATION**

1. Title of Dataset: Past volcanic activity predisposes an endemic threatened seabird to negative anthropogenic impacts

2. Corresponding author Information:

Helena Teixeira
UMR ENTROPIE - Écologie marine Tropicale des Océans Pacifique et Indien
Faculté des Sciences et Technologies
Université de la Réunion
15 Av. René Cassin CS 92003
97744 Saint Denis Cédex 9
La Réunion, France
Email:

1. Date of data collection: 2008 - 2018

2. Geographic location of data collection: Réunion Island, France

3. Information about funding sources that supported the collection of the data, data analyses, and computing and storage resources: Toulouse Occitanie (Bioinfo Genotoul, doi: 10.15454/1.5572369328961167E12), FEDER Smac (2020-2022, N° RE0022954), LIFE + Petrels (grant number: LIFE13 BIO/FR/000075), Bertarelli Foundation as part of the Bertarelli Programme in Marine Science (Project 822916)

4. Recommended citation f...