Data and code for "Impacts of Tropical Cyclones on Northwest Atlantic Seabirds: Insights from a Category 1 hurricane"

<b>About this repository</b>This repository contains *data* and *code* associated with the following publication:<br><br>Tori V. Burt, Robert J. Blackmore, Sydney M. Collins, Kyle J. N. d’Entremont, Christopher R. E. Ward, Josh Cunningham, Cerren Richards, Fiona Le Taro, Sabina I. Wilhelm, Amanda E. Bates, Stephanie Avery-Gomm, William A. Montevecchi. 2025. <b>Impacts of Tropical Cyclones on Northwest Atlantic Seabirds: Insights from a Category 1 hurricane. </b><i>bioRxiv. </i><br><b>Abstract</b>Tropical cyclones are annual occurrences in the western North Atlantic Ocean, where many seabird species are vulnerable to the environmental factors associated with extreme weather events. We summarize the history of tropical cyclones in Newfoundland, Canada, which hosts globally significant populations of seabirds. We examine the interactions that historical tropical cyclones have had with breeding seabirds by plotting the temporal association of Category 1 hurricanes with the breeding phenology of colonial seabirds in Newfoundland and identifying which major colonies have fallen within the pathways of these hurricanes. As a case study, we explore how Hurricane Larry (2021) coincided with increased stranding and mortality of Northern Gannets and Leach’s Storm-Petrels. The breeding seasons of Northern Gannets and Leach’s Storm-Petrels overlapped with all Category 1 hurricanes that have made landfall with Newfoundland from 1851 to 2024, with the central pathways of at least one hurricane passing over each of the six large Leach’s Storm-Petrel colonies and one of the three Northern Gannet colonies. For Northern Gannets, a notable stranding and mortality event occurred with a minimum count of 146 stranded and 130 dead from September 13 to 24, 2021. For Leach’s Storm-Petrels, a minor stranding and mortality event occurred with a count of 19 stranded and 16 dead from September 10 to 14, 2021, which was significantly higher than strandings and deaths reported during this period in 2020, 2022, 2023, and 2024. As global climate change drives a shift in the timing, frequency, severity, and attributes of tropical cyclones, we raise the concern that the impacts of tropical cyclones on breeding seabirds may worsen.<b>Data</b>This repository summarizes breeding phenology information for eight seabird species breeding in Newfoundland. This repository also contains a dataset of colony information for six large (&gt; 10,000 pairs) Leach's Storm-Petrel colonies and three Northern Gannet colonies in Newfoundland as of 2021. See the manuscript above for details. The details of each variable are described in the ReadMe file.<br>Feb_23_BreedingPhenology_hurricane.csvlesp_noga_large_colonies.csvThis repository also contains two collated datasets of reported on-land strandings and mortalities of Northern Gannets and Leach’s Storm-Petrels in eastern Newfoundland. See manuscript above for details. The details of each variable are described in the ReadMe file.<br>Gannet_Summary_HL_2024_11_26.csvHL_Lesp_Bdv_Cpaws_Mar_11_2025.csvThis repository also contains the subset of the Atlantic hurricane database (HURDAT2; https://www.nhc.noaa.gov/data/) of information on all Category 1 hurricanes that have made landfall with Newfoundland from 1851 to 2024, including "best tracks."<br>NL_hurricanes_cat1_best_tracks.csv<b>Code</b>The code required to reproduce Figure 1 (see manuscript above) is in Breeding_phenology.Rmd (input file is Feb_23_BreedingPhenology_hurricane.csv).The code required to reproduce Figure 2 (see manuscript above) is in Colony_risk_assessment.Rmd (input files are lesp_noga_large_colonies.csv and NL_hurricanes_cat1_best_tracks.csv).The code required to reproduce Figure 3 (see manuscript above) is in Hurricane_Larry_colonies.Rmd (input files are lesp_noga_large_colonies.csv and Hurricane Larry "best track" and wind radii (https://www.nhc.noaa.gov/data/tcr/index.php?season=2021&amp;basin=atl).The code required to reproduce Figures 4 and 5 (see manuscript above) are in NOGA_stranding_map.Rmd (input files are lesp_noga_large_colonies.csv and Gannet_Summary_HL_2024_11_26.csv) and LESP_stranding_map.Rmd (input files are lesp_noga_large_colonies.csv and HL_Lesp_Bdv_Cpaws_Mar_11_2025.csv), respectively. Shapefile for Hurricane Larry "best track" and wind radii can be found at https://www.nhc.noaa.gov/data/tcr/index.php?season=2021&amp;basin=atl.The code required to reproduce Figure 6 (see manuscript above) is in HL_stranding_comparison (input file is HL_Lesp_Bdv_Cpaws_Mar_11_2025.csv).<b>Software Requirements</b>Scripts are written for R version 4.2.2. (2022-10-31 ucrt). See scripts and the publication for packages and software citations.<b>Terms of use:</b>Anyone can share this material, provided it remains unaltered in any way, this is not done for commercial purposes, and the original authors are credited and cited (Attribution CC-BY-NC-ND).