The common murre (Uria aalge) is a medium-sized seabird found across the northern oceans. Murres are highly social birds that nest densely together on coastal cliffs. They feed primarily on small fish and dive underwater to catch their prey.
The global population of common murres is estimated to be around 20 million breeding pairs. However, some local populations have experienced dramatic declines in recent decades. This has led to concern that the species could be at risk of extinction in parts of its range.
In this article, we’ll examine whether the common murre is currently endangered worldwide or in certain regions. We’ll look at the major threats facing murres, conservation efforts, and what their current protected status is.
What is the current global population trend?
The global population of common murres is still estimated to be quite large at around 20 million pairs. However, the worldwide population trend has been decreasing over the last few decades.
According to the International Union for Conservation of Nature (IUCN) Red List, the global population is suspected to have declined by up to 1-3 million pairs since the 1980s. However, due to the uncertainty in estimating such a widely distributed population, the overall global decline is quantified by the IUCN as being less than 30%.
This level of decline alone has not been severe enough for the IUCN to consider changing the global status of the common murre from “Least Concern”. A 30% reduction typically warrants a status change to “Vulnerable”. However, many local and regional populations have been much more heavily impacted.
Population trends in different regions
| Region | Population trend |
|---|---|
| Eastern North America | Declined by 78% from 1975-2007 |
| Western North America | Declined by 62% from 1987-2009 in California |
| Iceland | Declined by 35% from 1983-2006 |
| Faroe Islands, Scotland, Ireland | Relatively stable |
| Greenland, Svalbard, Norway, Russia | Insufficient data but large populations remain |
The table above summarizes some of the population data from key regions. The largest declines have occurred along the coasts of eastern and western North America. Several European populations appear relatively stable while data deficiencies exist for northern coasts.
What are the major threats facing common murres?
The common murre faces a number of threats across its circumpolar range. The main threats include:
– Oil spills – Murres are especially vulnerable to the impacts of oil spills, which can kill many birds and destroy nesting colonies. Examples include the Exxon Valdez spill in Alaska and several recent spills off Newfoundland.
– Predation – With the decline of fish populations in some areas, murres have become more susceptible to predation. Examples include increased eagle predation in western North America and orca whale predation around Newfoundland.
– Bycatch – Murres are frequently caught as bycatch in gillnet fisheries. Tens of thousands drown annually in nets off Newfoundland.
– Extreme weather – Storms can wipe out entire breeding colonies. Climate change may be increasing extreme weather frequency in the Arctic.
– Overfishing – Declines in forage fish like capelin, herring, and sandlance may impact murre prey availability.
– Disturbance – Tourism, research, and other human activities can displace murres from preferred nesting habitat.
– Pollution – Ingestion of plastics and exposure to heavy metals impacts health and reproduction.
Many of these threats are increasing in frequency and severity. Their combined impact in addition to natural population fluctuations has led to the precipitous declines seen in eastern North America.
What conservation efforts are underway?
A variety of conservation initiatives aim to protect common murre populations:
– Monitoring programs – Ongoing monitoring tracks murre population trends at many colonies. This allows appropriate conservation action to be taken if numbers drop.
– Protecting breeding sites – Colonies are protected by restricting human access and habitat modification on breeding cliffs.
– Rehabilitation centers – Centers like the Alaska SeaLife Center rehabilitate downed murres and release them back to the wild.
– Preventing oil spills – Regulations aim to prevent oil spills from shipping. Spill response plans enable quicker clean up.
– Fishing regulations – Gillnet restrictions and harvest limits aim to reduce murre bycatch in fisheries.
– Public education – Education programs highlight threats and build public support for conservation.
However, murres remain vulnerable across their range and greater effort is likely needed, especially in regions with declining populations like eastern North America. Stronger fishing regulations, more protected colonies, and reduced oil spill risk would help ensure the future of this species.
What is the common murre’s protected status?
Globally, the common murre is listed as “Least Concern” on the IUCN Red List of Threatened Species. Their large total population size and range prevents them from being considered globally threatened.
However, many regional populations are listed as higher risk:
– Endangered in Nova Scotia and Newfoundland
– Threatened in Quebec, New Brunswick, and Maine
– Near threatened or vulnerable in Norway, Sweden, and Iceland
In the United States, the common murre is protected by the Migratory Bird Treaty Act which prohibits harming or killing the birds. They are also protected as a seabird species of special concern under the Oil Pollution Act.
Despite protections, status assessments for common murres have not kept pace with their dramatic population declines in eastern North America. Updated endangered species listings may be warranted in Canada and the northeastern United States.
Conclusion
While the global population of common murres remains in the millions, worrisome regional declines have occurred, especially along the Atlantic coasts of North America.
Precipitous drops in murre numbers in eastern Canada and the northeastern United States warrant an endangered designation in these areas. Strengthened legal protections, fisheries restrictions, oil spill prevention, and protected breeding habitat could help stabilize these declining regional populations.
In other parts of the murre’s range like Iceland, Greenland, and the Faroe Islands, populations appear relatively stable. But continued monitoring is needed to ensure new threats do not emerge.
The common murre’s status as a marine sentinel species means their populations trends signal ocean health. Their declines indicate marine ecosystems require greater stewardship and protections across the northern hemisphere. With wise conservation measures, we can ensure common murres continue diving through northern waters for centuries to come.
