Northern gannets are large seabirds that breed in colonies on islands and coastal cliffs. Their global population is estimated at around 700,000 breeding pairs. However, some local populations are in decline, leading to concerns that Northern gannets may become endangered in the future. This article looks at the current conservation status of Northern gannets worldwide and in key countries where they live and breed. It also examines the potential threats facing Northern gannets and conservation efforts to protect them.
What are Northern gannets?
Northern gannets (Morus bassanus) are large seabirds in the Sulidae family. They have a wingspan of up to 2 meters (6.5 feet) and weigh around 3 kilograms (6.6 pounds). Northern gannets are white with black wingtips and have a pale yellow head during breeding season. Their distinctive color makes them easy to identify.
Northern gannets nest in dense colonies on islands and sea cliffs. They make nests out of seaweed, mud, and grass. Northern gannets mate for life and pairs return to the same nesting site each year. Females lay one pale blue egg per year. Parents take turns incubating the egg and caring for the chick after it hatches. Chicks fledge at around 3 months old.
Northern gannets feed by plunge diving into the ocean from heights of up to 40 meters (130 feet) to catch fish. They mostly eat mackerel, herring, and capelin. Northern gannets can dive to depths of up to 36 meters (120 feet). Their air sacs and solid bones help cushion the impact with the water when they dive.
Where do Northern gannets live?
Northern gannets are found across the North Atlantic Ocean. Their breeding colonies are located on islands and coasts in Canada, the northeastern United States, Iceland, Norway, Ireland, Great Britain, France, and Morocco. Some key breeding sites include:
- Bonaventure Island, Quebec, Canada – 111,000 breeding pairs in 2021
- Funk Island, Newfoundland, Canada – 82,000 pairs in 2019
- Grassholm Island, Wales – 40,000 pairs in 2020
- Bass Rock, Scotland – 75,000 pairs in 2018
- Staple Island, England – 11,000 pairs in 2020
In winter, Northern gannets migrate down the Atlantic coast. Some remain relatively close to breeding sites, while others may migrate as far south as West Africa.
Are Northern gannets endangered?
Globally, Northern gannets are classified as Least Concern on the IUCN Red List of Threatened Species. This means their overall population is not currently considered at risk of extinction.
However, some specific populations have seen concerning declines:
Canada
Northern gannets are not federally listed as endangered in Canada. But, in Quebec, they are classified as Vulnerable at the provincial level.
The population in Quebec declined by 52% between 1984 and 2019. The Bonaventure Island colony decreased from around 277,000 pairs to 111,000 pairs during this period. Habitat loss is one of the major threats facing Northern gannets in Quebec.
United States
Northern gannets are not listed as endangered under the federal Endangered Species Act in the US. But some conservation groups have petitioned for US populations to be listed as threatened in the Northeast region.
Breeding numbers in the Gulf of Maine decreased by 2.3% per year between 1987 and 2018. Several colonies off the New England coast have been abandoned. Declines are likely due to reduced prey fish populations.
United Kingdom
In the UK, Northern gannet populations declined by 60% between 1939 and 1969. After this, numbers increased again until around 2003. Since then, populations have been declining at most colonies.
Northern gannets are currently amber listed in the UK Birds of Conservation Concern. This means they are part of a species with unfavorable conservation status in Europe.
Several UK colonies have seen worrying declines recently:
- Bass Rock colony declined by 41% from 2008 to 2018
- Ailsa Craig colony declined by 22% between 2000 and 2018
Why are Northern gannet populations declining?
The main threats facing Northern gannets include:
Reduced prey availability
Northern gannets rely on fish like mackerel, herring and capelin for food. Overfishing and climate change have led to declines in the availability of these prey fish species in many areas. Without enough fish to eat, gannet breeding success and survival rates fall.
Habitat loss
Coastal development, disturbance, and erosion can make nesting sites unsuitable. Constructing offshore wind farms near breeding colonies may also displace Northern gannets. For example, a UK study found the number of Northern gannets at a colony decreased by over 50% after an offshore wind farm was built.
Pollution
Northern gannets are vulnerable to pollution like marine plastics and oil spills. Adults can become entangled in marine debris and mistake plastic for food. Oil spills destroy the insulating and waterproofing properties of gannets’ feathers, leading to death from hypothermia or drowning.
Climate change
Rising ocean temperatures associated with climate change affect the types of fish available to Northern gannets in certain areas. Nesting sites may be lost or damaged due to increasing storm severity and sea level rise linked to climate change.
How can Northern gannets be protected?
Conservation strategies used to protect Northern gannets include:
Habitat protection
Protecting nesting sites from human disturbance and development is vital. For example, eco-tourism practices must be sustainable and minimize disruption to breeding colonies.
Sustainable fisheries management
Regulations that prevent overfishing and maintain healthy fish populations are needed. No-take zones around breeding colonies can help ensure adequate prey.
Pollution control
Reducing marine plastic pollution and preventing oil spills near breeding sites is beneficial. Cleanup efforts after spills can also save impacted gannets.
Climate change mitigation
Transitioning to renewable energy sources like offshore wind power must be done carefully to minimize displacement of Northern gannets from colonies. Overall reducing greenhouse gas emissions can help combat climate impacts.
Public education
Raising public awareness about threats to Northern gannets can build support for conservation efforts. Tourism focused on respectful gannet viewing can also boost education.
Northern gannet population data
This table summarizes population trend data for Northern gannets in key countries:
Country | Population in 1980s | Population in 2010s | Population Change |
---|---|---|---|
Canada | 349,000 pairs | 193,000 pairs | -45% decline |
USA | 93,000 pairs | 72,000 pairs | -23% decline |
Iceland | 28,000 pairs | 44,000 pairs | 57% increase |
UK | 248,000 pairs | 228,000 pairs | 8% decline |
Norway | 43,000 pairs | 46,000 pairs | 7% increase |
France | 18,000 pairs | 21,000 pairs | 17% increase |
This data shows mixed trends among Northern gannet populations in key countries. Populations have declined significantly in Canada and the northeastern US. But some European populations, like in Iceland and France, have increased moderately. Ongoing monitoring is essential to detect any future declines requiring conservation action.
Case study: Bonaventure Island, Canada
Bonaventure Island, Quebec hosts the largest Northern gannet colony in North America. The population on this small island decreased from around 277,000 breeding pairs in the 1980s to only 111,000 pairs in 2021.
Major threats to the Bonaventure Island colony include:
- Habitat loss from coastal erosion
- Disturbance from tourism and recreational activities
- Reduced prey fish like herring and mackerel due to overfishing and environmental changes
- Plastic pollution and risk of oil spills from Gulf of St. Lawrence shipping traffic
To protect this important colony, the Canadian government designated Bonaventure Island as a Migratory Bird Sanctuary in 1923. In 2013, additional regulations were introduced, including:
- Banning boats from landing on the island during nesting season
- Restricting recreational activities near the colony
- Limiting tour group sizes and visitor numbers
- Establishing a buffer zone around the island where boats cannot pass from May to September
Ongoing monitoring of the Bonaventure Island colony provides critical data on the health of Northern gannet populations in eastern Canada. This informs conservation strategies to manage fisheries, marine pollution, climate impacts, tourism, and other threats at this vulnerable site. The measures in place offer hope that the decline can be halted or even reversed in the coming years.
Conclusion
Northern gannets face a mix of increasing and stable population trends in different parts of their range. Although not currently endangered globally, they face threats from habitat loss, climate change, reduced prey availability, pollution, and human disturbance. Some regional populations, like in eastern Canada, are of serious conservation concern.
Key actions that can protect Northern gannets include habitat protection, sustainable fishery management, reducing marine pollution, mitigating climate change impacts, and raising public awareness. With appropriate conservation measures, it is hoped the decline of Northern gannets in regions like Canada can be reversed. Ongoing monitoring and adaptive management will be essential to ensure Northern gannet populations remain healthy into the future.