Brandt’s cormorant (Phalacrocorax penicillatus) is a medium-sized seabird found along the Pacific coast of North America. They are distinguished by their dark plumage, long neck, and hooked bill. Brandt’s cormorants are colonial nesters, gathering in large breeding colonies on rocky islands and cliffs along the coast.
Brandt’s cormorants feed on small fish which they catch by pursuit diving, often swimming down to depths of over 150 feet. They are most common along rocky shorelines, estuaries, and kelp beds where their prey is abundant.
There has been some concern about potential threats to Brandt’s cormorant populations in recent years. Their numbers declined significantly in the 1980s, prompting interest in their conservation status. This article will examine the question: Are Brandt’s cormorants endangered?
Brandt’s Cormorant Population Trends
Historically, Brandt’s cormorants experienced sharp declines in their populations in the late 19th and early 20th century due to egging and hunting. Their numbers rebounded around the 1970s with increased protections.
In the 1980s, their populations crashed again by nearly 70%. Scientists identified the likely causes as changes in ocean conditions, including rising sea temperatures, declining fish stocks, and competition with commercial fisheries.
Since the 1990s, Brandt’s cormorant numbers have stabilized and even begun increasing again in some regions. However, their population levels remain below historical numbers.
According to the most recent estimates, there are approximately 200,000 breeding pairs of Brandt’s cormorants across their range. Their worldwide population is estimated at well over 400,000 individuals.
The following table summarizes population trend data for Brandt’s cormorants in recent decades:
Year | Estimated Number of Breeding Pairs |
---|---|
1970s | 100,000-150,000 |
1980s | 30,000-50,000 |
2000s | Over 200,000 |
This data shows a concerning decline in the 1980s followed by a recovery in more recent decades. While the recent population trends are encouraging, Brandt’s cormorant numbers still remain below their historical levels.
Brandt’s Cormorant Conservation Status
Several organizations have assessed the conservation status of Brandt’s cormorants in recent years:
IUCN Red List
The IUCN Red List categorizes Brandt’s cormorant as Least Concern. They are not considered threatened or near threatened with extinction at this time. Their large range and population size are reasons for the Least Concern designation. However, the IUCN recommends continued monitoring given the historical population declines.
ESA Listing
Brandt’s cormorants are not listed under the federal Endangered Species Act (ESA). In 1997, the U.S. Fish and Wildlife Service conducted an extensive status review and determined listing under the ESA was “not warranted at this time.”
State Listings
No U.S. states currently list Brandt’s cormorants as threatened, endangered, or a species of special concern.
In the 1990s, California considered listing them as threatened but withdrew the proposal given evidence of population increases. Baja California, Mexico lists Brandt’s cormorants as threatened but other Mexican states do not.
Threats Facing Brandt’s Cormorants
While Brandt’s cormorants are not currently endangered, they still face a variety of threats to their future viability. Some of the major threats include:
Changing Ocean Conditions
Rising ocean temperatures, declining fish stocks, algal blooms, and other ocean changes can negatively impact Brandt’s cormorant prey availability and foraging success. Climate change may exacerbate these issues.
Competition with Fisheries
There is competition between Brandt’s cormorants and commercial fisheries for prey species like anchovy, rockfish, and sardine. Declining fish stocks put greater pressure on this food resource.
Disturbance of Nesting Sites
Brandt’s cormorants are sensitive to disturbance during nesting and breeding. Human activities near colonies, like construction, recreation, and research studies can cause adults to abandon nests and chicks.
Oil Spills
Oil spills pose a major threat, especially in California which is prone to spills. Even small amounts of oil can ruin the waterproof quality of cormorant feathers, resulting in hypothermia.
Entanglement in Fishing Gear
Brandt’s cormorants frequently become hooked or entangled in commercial and recreational fishing lines, lures, nets and traps. These encounters often result in death from drowning, starvation or injury.
Efforts to Protect Brandt’s Cormorants
While not currently endangered, Brandt’s cormorants have federal and state protections in place to help conserve populations:
Federal Protections
– Protected under the Migratory Bird Treaty Act: prohibits harming or killing cormorants as well as disrupting active nests.
– May be protected under the Marine Mammal Protection Act in the future: this act was amended in 1994 to include seabirds but cormorants have not yet been added.
State Protections
– Protected under various state laws prohibiting disturbing or destroying active nests.
– Some states have designated important cormorant nesting sites as Areas of Special Biological Significance.
– Grants for research and monitoring of cormorant populations.
Colony Protection Efforts
– Restrict human access/disturbance at important nesting colonies
– Eliminate predators at breeding sites
– Habitat enhancement like installing nesting platforms
– Oil spill response training in breeding areas
Conclusion
In conclusion, Brandt’s cormorants are not currently endangered or threatened with extinction. Their populations have rebounded from declines in the 1980s and some regions have seen increased growth in recent years.
However, Brandt’s cormorant numbers still remain below historical levels and they face a variety of ongoing conservation threats. Most experts emphasize the need for continued monitoring and protection efforts to ensure populations remain stable into the future.
While the outlook is currently cautiously optimistic, it will be important to keep a close watch on Brandt’s cormorant population trends and be prepared to increase conservation actions if future declines resume. Maintaining healthy Brandt’s cormorant numbers along the Pacific coast benefits both the cormorants themselves and the entire coastal marine ecosystem they are an integral part of.