News

NINA news

Feathers reveal mercury contamination in alcids in the Arctic

Published on: 4. December 2020
Author: Erlend Lorentzen / SEAPOP

More than a quarter of the individual auks in which mercury levels were measured outside the breeding season exceeded the toxicity threshold.

Feathers reveal mercury contamination in alcids in the Arctic
The mercury body burden in Brünnich’s guillemots and other alcids is excreted into growing feathers after moulting, which happens twice a year. Photo: Erlend Lorentzen

In a large pan-Arctic study, a multinational group of researchers have investigated the concentrations of mercury (Hg) in nine alcid species breeding in the Atlantic and Pacific Oceans. Large differences were found between regions and seasons, indicating that some areas and periods pose greater threats to seabirds than others in terms of exposure to mercury, a contaminant that is known to have negative effects on seabird health and reproduction.

Top predators at risk

Concentrations of mercury have increased in marine ecosystems over the last decades through anthropogenic emissions. Mercury, which is of concern for wildlife and human health, is assimilated by organisms through their diet and biomagnifies through food webs. Top- and meso-predators, such as marine mammals and seabirds, therefore end up containing the highest concentrations of mercury. Using data collected as part of the SEAPOP monitoring programme and the SEATRACK project, a large international group of researchers has investigated the seasonal mercury contamination of seabirds on a large, pan-Arctic scale.

Different feathers tell different stories

Since approximately 70% to 90% of the mercury body burden is excreted into growing feathers, the researchers could utilize feather samples to get information about mercury accumulated in the birds during the period prior to the last moult. Alcids undergo a partial moult of the head, cheeks and neck in spring, in addition to a complete moult of all feathers in the autumn. Thus, mercury in head feathers sampled in the summer inferred mercury contamination during the previous non-breeding period, while body feathers contained mercury accumulated throughout the previous breeding season. Feather samples for this study were taken from nine alcid species in 28 breeding colonies located in the North Atlantic and North Pacific Oceans.

Spatial and seasonal variations

There turned out to be large variations in contamination levels within and between the different regions studied, and between seasons. The accumulations of mercury in the alcids were higher outside the breeding period, showing that the birds are more exposed to contaminants in their wintering areas and during migration than when they are close to the colonies. The highest mercury concentrations, both in the breeding and non-breeding seasons, were observed in the West Atlantic region, followed by the Pacific and the East Atlantic. The differences in mercury concentration in seabirds between breeding and non-breeding season were also larger in the West Atlantic than in the other two regions. Moreover, in most of the seabird colonies, the researchers observed individual mercury concentrations above 5 μg g−1 dry weight, a level at which negative effects on health and reproductive abilities can be expected. The study indicates that the non-breeding period might represent an important risk for sensitive populations, especially those breeding in the West Atlantic Arctic, and it demonstrates the need to continue close monitoring of seabird populations to understand the implications of mercury exposure on population dynamics.

Read article: Seasonal variation of mercury contamination in Arctic seabirds: A pan-Arctic assessment​

Mercury concentrations in alcids varied between the breeding (green) and non-breeding period (red) and between the study colonies. Ill. Céline Albert

Mercury concentrations in alcids varied between the breeding (green) and non-breeding period (red) and between the study colonies. Ill. Céline Albert

Marine organisms assimilate mercury through their diet, and the contaminant magnifies through the food web. The photo shows an Atlantic puffin with herring larvae. Photo: Venke Ivarrud/SEAPOP

Marine organisms assimilate mercury through their diet, and the contaminant magnifies through the food web. The photo shows an Atlantic puffin with herring larvae. Photo: Venke Ivarrud/SEAPOP

Print

Kittiwakes find refuge on offshore oil rigs

19.11.2020
Offshore oil rigs serve as a breeding refuge for Norwegian Black-legged Kittiwakes. Although they are few in number, these birds produce more chicks than kittiwakes in natural colonies along the coast, to the benefit of the impoverished Norwegian Kittiwake population. ...
Read more..

Seabird experts in CAFF propose a new kittiwake conservation plan

04.11.2020
The Circumpolar Seabird Group under CAFF and the Arctic Council has proposed a conservation plan for the black-legged kittiwake Rissa tridactyla , a species which has been declining severely since the 1970s. Four main objectives are identified, and specific action...
Read more..

Palm oil certification brings mixed outcomes to neighbouring communities

02.11.2020
Sustainable certification of oil palm plantations can reduce poverty, but the timing of certification is among the factors that influence the effect.
Read more..

Seabirds and kelp harvest – conflict or harmony?

18.09.2020
Foraging shags and commercial kelp harvesters very often utilize the same marine areas.  
Read more..

How efficient are mitigation measures for bird-friendly wind power?

14.08.2020
Simple measures can make wind turbines more bird friendly. New research shows that measures such as painting the rotor blades or towers, using UV-light and smart micro-siting of wind turbines, decreases the risk for bird collisions considerably.
Read more..

Wild salmon’s wild journey in the ocean

28.05.2020
Last spring Atlantic salmon were tagged with satellite tags in Southern Norway. Now they have phoned home.
Read more..

Vultures respond to auditory cues

20.05.2020
Vultures and other avian scavengers characteristically circle the skies, scanning the ground for carcasses. New research has revealed that these birds can, in addition to sight, respond to auditory cues indicative of potential foraging opportunities.
Read more..

Carbon emissions have made the world a greener place, which has a cooling effect

07.02.2020
The very same carbon emissions responsible for harmful changes to climate are also fertilizing plant growth, which in turn is somewhat moderating global warming. This affects also remote places, like the High Arctic.
Read more..

Animals take climate action

02.09.2019
Migratory animals are actively adjusting their traditions to climate change.
Read more..

A ray of hope for the golden deer of Myanmar

29.05.2019
Developing state-of-the-art statistical tools that combine different sources of data has allowed researchers from Norway and Myanmar to make robust estimates of population size for an often-overlooked population of one of the world’s most threatened deer species. The r...
Read more..

Have you checked your baggage for alien species?

11.04.2019
Are you travelling to the Arctic? Seeds, insects and parasites can travel with you as stowaways without your knowledge. A new short film explains how you can avoid bringing unwanted species that can threaten the vulnerable Arctic environment.  
Read more..

China and India dominate in greening the Earth

13.02.2019
A new study reports China’s planting of trees and India’s intensive crop cultivation as the main reasons why the Earth is greening throwing doubt on the role of carbon dioxide fertilization, which climate change skeptics have touted as the beneficial effects of otherwi...
Read more..

First estimates of body mass change between the breeding and wintering stage in Atlantic Puffins.

07.01.2019
By measuring body mass and wing length of adult Atlantic Puffins on their breeding grounds and in their wintering areas near the Faroe Islands, researchers have now estimated the seasonal changes in body mass for two populations breeding in Norway and Scotland.
Read more..

Long-term side-effects of abdominal implants in brown bears

15.10.2018
A recent study from the Scandinavian Brown Bear Research Project has shown serious side effects from radio transmitters implanted into the abdominal cavity of brown bears.
Read more..

Environmental benefits of leaving offshore infrastructure in the ocean

05.07.2018
More than 7500 oil and gas platforms and wind turbines will become obsolete in the next few decades. Full removal may not be the best plan after all, according to new survey of international experts.
Read more..

Standardization and facilitation of seabird data for use in impact and environmental risk assessments

02.07.2018
A new NINA-report gives recommendation on how seabird data should best be used in impact and environmental risk assessments.
Read more..

NINA Annual Report 2017

27.06.2018
NINA’s key statistics and activities throughout 2017. 
Read more..

Flexibility in the foraging behaviour of the kittiwake may buffer the effect of marine environmental changes

30.01.2018
Recent Norwegian research shows that the black-legged kittiwake is surprisingly flexible when it comes to finding food for itself and its chicks. The ability to adapt makes this small gull robust to changes in the marine environment – that is, if it has access to suita...
Read more..

Impacts of salmon lice on wild Atlantic salmon and sea trout

10.01.2018
New report concludes: Considerable evidence exists that there is a link between farm-intensive areas and the spread of salmon lice to wild Atlantic salmon and sea trout. 
Read more..