Hidden life discovered near the North Pole

Québec, july 6th, 2017 – For more than half a century, researchers have camped near Ward Hunt Lake at the remote northern tip of Canada thinking that it was frozen to the bottom throughout the year and largely devoid of life.

This week in the Nature journal ‘npj Biofilms and Microbiomes', a team from Université Laval, Quebec City, reports their observations showing that the bottom of this lake is coated with a mysterious orange film that is packed with diverse microbes.

Much to the surprise of the researchers, this colourful, deep-living community had a greater variety of species and functions than those found in open shallow waters. The thick biofilm of living cells included many species adapted to low or zero oxygen conditions, as well as some new species never before described.

The authors conclude that their study at Ward Hunt Lake provides a window into the future state of the Arctic.

As climate warming reduces the amount of ice in the millions of waterbodies across the northern landscape, it is becoming less likely to experience complete freeze-up, and more likely to retain liquid water under the ice during winter darkness. The results from Ward Hunt Lake indicate that such conditions will lead to bottom oxygen loss and the production of greenhouse gases, especially methane, providing an accelerator effect on global climate change. Even the thick ice on Ward Hunt Lake has thinned in recent years, and in two years (2011 and 2012) it melted out completely at the end of summer.  

Alexander Culley, co-leader of the project and professor in the Dept de biochimie, microbiologie et bioinformatique describes the astonishment of discovering this richness of life: «We drilled through 2 m of ice at a place where radar measurements had indicated liquid water beneath to a depth of 10 m. We then lowered down a GoPro video camera with a waterproof lamp. It was not until we had hiked back to our base camp later that evening and put the flashcard from the GoPro in our computer that we saw that the bottom was teeming with life. Totally the opposite to what we had originally thought!»

It took two years to get samples from the bottom of this far northern lake, only 770 km from the North Pole, and one of the most difficult and expensive places to access in the Arctic.

«Sentinel North provided an ideal opportunity to analyse these samples using advanced molecular techniques, and to combine forces across departments and research centres» said Alexander Culley, a member of the Institut de biologie intégrative et des systems and Centre d'études nordiques  (CEN).

«One of the principal themes of Sentinel North is the genetic analysis of microbiomes, the ensemble of microscope life and life functions that we now know underpins all living systems, including humans and ecosystems» says Warwick Vincent, professor in the Dépt de biologie, Takuvik and Centre d'études nordiques. «These unique samples from an extreme High Arctic environment provided a superb start to this integrative approach. The work will continue with other members of the program on subjects ranging from the Arctic Ocean microbiome to skin biofilms that occur on important fish species such as Arctic Char and that affect their health and survival.»   

Sentinel North is a largescale multidisciplinary program at Université Laval funded by the Canada First Research Excellence Fund (CFREF).

The paper was first authored by Vani Mohit, with co-authors Alexander Culley, Connie Lovejoy, Frédéric Bouchard and Warwick Vincent. The publication includes an online edited version of the first GoPro video that revealed this hidden world beneath the ice.

Publication:

Mohit, V., Culley, A., Lovejoy, C., Bouchard, F. and Vincent, W.F. 2017. Hidden biofilms in a far northern lake and implications for the changing Arctic. npj Biofilms and Microbiomes, in press.

About Université Laval
Université Laval, located in the world heritage city of Québec, is the oldest French-language university in North America. One of Canada's top research universities, it is ranked 7th among the country's institutions of higher learning, with a research budget of over$330 million last year. Université Laval boasts 3,685  professors, lecturers, and teaching staff who share their knowledge with some 42 500 students, including 25%  at the graduate level.

About Sentinel North
In 2015, Université Laval received a$98 million grant from the federal government's Canada First Research Excellence Fund, the largest research grant in its history. The Fund helps Canadian universities compete with the best in the world and implement large-scale, transformational and forward-thinking institutional strategies. Among other strengths, Sentinel North distinguished itself with its focus on transdisciplinairy research. In a context of accelerating climate change and social and economic development in the arctic and subarctic regions, Sentinel North will provide knowledge to monitor and prepare for changes in northern environments at scales ranging from microbiota to entire ecosystems and using the best technology and intervention strategies in the pursuit of sustainable health and development. sentinellenord.ulaval.ca/en