An international research team of Canadian and French university and government scientists examined a ~5,800-year record of a seabird population dynamics using lake sediments from a Northwest Atlantic island. The authors showed that expanding human settlement over 200 years ago coincided with a severe population decline of an ecologically important seabird. This study concluded that the current seabird population is only ~16% of its potentical size before human settlement.
The Leach’s Storm-petrel, the most common seabird nesting in the Western Atlantic, is a small, nocturnal seabird that nests in large colonies numbering in the millions of individuals. Globally, surveys indicate that the storm-petrel populations are now vulnerable and have declined by over 30% since the 1980s, with no clear consensus on the cause. Interestingly, one colony on Grand Colombier Island (the third largest in the world), in the St. Pierre and Miquelon Archipelago 17 km southwest of Newfoundland, was believed to be relatively stable based on the limited available monitoring.
“Since Grand Colombier was the only known major colony of storm-petrels that was believed to be stable based on a few available surveys since the 1980s, we decided to study the long-term seabird dynamics on the island to see if its population has remained stable through its history.” says lead author Matthew Duda, a doctoral candidate at Queen’s University’s Paleoecological Environmental Assessment and Research Laboratory (PEARL). “The first step was to explore the long-term population trends before surveying began in the 1980s and determine whether the population was truly stable, and if not, understand the true long-term population trends.”
Storm-petrels build burrow nests on islands, often around freshwater ponds. The researchers showed that the ponds’ sediments preserve a record of seabird occupation because their guano causes chemical and biological changes that are permanently recorded in the sediment layers. As a result, pond sediments provide a ‘history book’ of past changes in the seabird population. “By depositing large volumes of acidic and nutrient-rich feces, the seabirds change the aquatic and terrestrial landscape”, notes co-author Dr. John Smol, a biology professor and the Canada Research Chair in Environmental Change at Queen’s University. “Lake sediments are like a time machine. By examining the information preserved in dated sediment cores from storm-petrel impacted ponds, we can reconstruct past population trends going back centuries or millennia, long before any monitoring programs were underway. The distant past is where many important clues lay hidden. From this we can reconstruct natural population trends as well as the impacts of humans”.
“Our study identified a number of surprising results”, explains Duda. “We showed that the colony underwent large, natural fluctuations over the last ~5,800 years. A more striking finding was how the natural fluctuations were disrupted and the population plummeted at the start of 19th century, at a time corresponding with European settlement nearby the island”. The researchers attributed this major decline to human encroachment and expansion. Although the colony is currently believed to be stable, it is only ~16% of the likely potential size that it was prior to European settlement. “The ‘human footprint’ on past population dynamics is clearly visible in the environmental record”, concludes Duda.
The study was published in Proceedings of the National Academy of Sciences in the United States of America.
Other members of the research team include Sylvie Allen-Mahé, Christophe Barbraud, Jules Blais, Amaël Boudreau, Rachel Bryant, Karine Delord, Christopher Grooms, Linda Kimpe, Bruno Letournel, Joeline Lim, Hervé Lormée, Neal Michelutti, Gregory Robertson, Frank Urtizbéréa, and Sabina Wilhelm.
Funding was provided by the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Kenneth M. Molson Foundation.
Contact Information for authors:
Matthew Duda
Paleoecological Environmental Assessment and Research Lab (PEARL), Department of Biology, Queen's University, Kingston, ON, Canada
16mpd3@queensu.ca
Sylvie Allen-Mahé
Maison de la Nature et de L’Environnement, Place des Ardilliers, BP8333 Miquelon, Langlade, St. Pierre et Miquelon
sylvieallenmahe@hotmail.com
Christophe Barbraud
Centre d’Études Biologiques de Chizé, UMR 7372 du CNRS-La Rochelle Université, 79360 Villiers-en-Bois, France
Christophe.BARBRAUD@cebc.cnrs.fr
Jules M. Blais
Department of Biology, University of Ottawa, 30 Marie Curie Pvt., Ottawa, ON K1N 6N5, Canada
Jules.Blais@uottawa.ca
Amaël Boudreau
Association SPM Frag’îles, 13 Rue des Capelanniers, BP4421, 97500 Saint Pierre et Miquelon
amael_b@hotmail.fr
Rachel Bryant
Department of Philosophy, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C 1A4, Canada
rachel.bryant@utoronto.ca
Karine Delord
Centre d’Études Biologiques de Chizé, UMR 7372 du CNRS-La Rochelle Université, 79360 Villiers-en-Bois, France
Karine.DELORD@cebc.cnrs.fr
Christopher Grooms
Paleoecological Environmental Assessment and Research Lab (PEARL), Department of Biology, Queen's University, Kingston, ON, Canada
groomsc@queensu.ca
Linda Kimpe
Department of Biology, University of Ottawa, 30 Marie Curie Pvt., Ottawa, ON K1N 6N5, Canada
linda.kimpe@uottawa.ca
Bruno Letournel
Office Français de la Biodiversité, Service Départemental de Saint-Pierre-et-Miquelon, 97500 Saint Pierre et Miquelon
Bruno.Letournel@oncfs.gouv.fr
Joeline Lim
Paleoecological Environmental Assessment and Research Lab (PEARL), Department of Biology, Queen's University, Kingston, ON, Canada
joeline.lim@queensu.ca
Hervé Lormée
Office Français de la Biodiversité–Direction de la Recherche et de l'Appui Scientifique – Unité Avifaune Migratrice, Station de Chizé, Carrefour de la Canauderie 79360 Villiers-en-Bois, France
herve.lormee@ofb.gouv.fr
Neal Michelutti
Paleoecological Environmental Assessment and Research Lab (PEARL), Department of Biology, Queen's University, Kingston, ON, Canada
nm37@queensu.ca
Gregory Robertson
Wildlife Research Division, Environment Canada and Climate Change, 6 Bruce Street, Mount Pearl, NL A1N 4T3, Canada
greg.robertson@canada.ca
Frank Urtizbéréa
Direction Territoriale de l’Alimentation et de la Mer, Service Agriculture, Eau et Biodiversité, Quai de l’Alysse, BP4217, 97500 Saint Pierre et Miquelon
urtizberea.frank@gmail.com
Sabina I. Wilhelm
Canadian Wildlife Service, Environment Canada and Climate Change, 6 Bruce Street, Mount Pearl, NL A1N 4T3, Canada
sabina.wilhelm@canada.ca
John P. Smol
Paleoecological Environmental Assessment and Research Lab (PEARL), Department of Biology, Queen's University, Kingston, ON, Canada
smolj@queensu.ca
