Smithsonian/American Herring Gull: Profile, Traits, Facts, Range

American herring gull

The American herring gull, with its distinctive appearance, wide habitat range, diverse diet, and particular nesting habits, is a fascinating bird that exemplifies adaptability and resilience. Whether observed on coastal cliffs, inland lakes, or urban dumpsters, this gull demonstrates a remarkable ability to thrive in various environments. Its presence across North America and its role in the ecosystem underscores the importance of understanding and appreciating this adaptable and widespread bird species.

Smithsonian/American Herring Gull: Profile, Traits, Facts, Range

The American herring gull, also known by the name Smithsonian gull, boasts the scientific designation Larus smithsonianus or sometimes Larus argentatus smithsonianus. This bird is a substantial species of gull that primarily breeds across the expanse of North America. The American Ornithologists’ Union treats it as a subspecies of the more broadly recognized herring gull, Larus argentatus. Notable for its size and robust nature, this gull plays a significant role in its ecosystem, reflecting its adaptability and wide-ranging presence across the continent.

Distinctive Physical Characteristics

The adult American herring gull presents a striking appearance with its white plumage contrasted by a grey back and wings. The wings feature distinctive black wingtips adorned with white spots, creating a vivid pattern that makes identification easier. The legs are a notable pink hue, adding to its unique look. In contrast, the immature American herring gull displays a gray-brown coloration that is markedly darker and more uniform compared to their European counterparts. The young gulls also possess a darker tail, which helps differentiate them during their developmental stages.

Habitat and Distribution

This gull is remarkably versatile in its habitat choices, thriving in diverse environments such as coasts, lakes, rivers, and even garbage dumps. The adaptability of the American herring gull to various habitats is a testament to its opportunistic nature and ability to find food and shelter in numerous settings. Whether soaring above the ocean waves, scavenging along lake shores, or foraging in urban refuse sites, these gulls are a common sight, illustrating their widespread distribution and ecological success.

Varied Diet

The American herring gull has a broad and eclectic diet, consuming a range of invertebrates and fish, along with many other items it encounters. This dietary flexibility allows the gull to thrive in various environments, ensuring it can sustain itself regardless of the season or location. From plucking fish from the water to scavenging human waste, its feeding habits reflect both opportunism and resourcefulness. This varied diet is crucial for its survival and reproductive success, making it a resilient species in changing environments.

Nesting and Reproduction

Typically, an American herring gull will nest near water, constructing its nest as a simple scrape on the ground. The nest is usually situated in a relatively safe and secluded area to protect the eggs from predators. The female lays around three eggs, which are incubated by both parents. The nesting sites are often chosen for their proximity to food sources and safety from potential threats. The commitment of both parents to the care of their eggs and young is a key factor in the survival of the chicks, highlighting the importance of their nesting habits.

Physical Characteristics

The American herring gull is a robust and substantial bird, distinguished by its strong and elongated bill, which is particularly powerful. Its chest is full and prominent, giving the gull a sturdy and formidable appearance.

Additionally, the gull’s forehead slopes gently, contributing to its streamlined and aerodynamic look. These features combine to create a bird that is not only large but also impressive in its physical presence, capable of withstanding various environmental challenges. The American herring gull’s overall build allows it to dominate in its habitat, easily maneuvering through both air and water. Its physical traits are well-adapted for scavenging and hunting, making it a versatile predator.

Male and Female Dimensions

Male American herring gulls are notably larger than their female counterparts. Males typically measure between 60 to 66 cm (24 to 26 inches) in length and weigh between 1,050 to 1,650 grams (2.31 to 3.64 pounds). Females, on the other hand, are slightly smaller, ranging from 53 to 62 cm (21 to 24 inches) in length and weighing between 600 to 900 grams (1.3 to 2 pounds).

This sexual dimorphism is common among many bird species, where males are often larger, potentially giving them an advantage in terms of strength and territorial defense. The size difference also reflects their roles within their social structure and mating behaviors, where larger males might be more successful in attracting mates and fending off rivals.

Wingspan Range

The wingspan of the American herring gull is particularly impressive, ranging from 120 to 155 cm (47 to 61 inches). This extensive wingspan enables the gull to soar gracefully and cover large distances with minimal effort. The broad wings are adapted for gliding over long stretches of water and land, aiding in their migratory journeys and daily foraging flights.

The large wingspan also contributes to their ability to perform aerial maneuvers while hunting or evading predators. This adaptation is crucial for their survival, allowing them to efficiently exploit a wide range of habitats from coastal areas to inland regions.

Detailed Measurements

When examining the American herring gull’s physical measurements in more detail, its wing chord measures between 41.2 to 46.8 cm (16.2 to 18.4 inches), which refers to the length from the shoulder to the tip of the wing. The bill length ranges from 4.4 to 6.2 cm (1.7 to 2.4 inches), suitable for catching a variety of prey and scavenging.

The tarsus, or the lower leg part of the gull, measures between 5.5 to 7.6 cm (2.2 to 3.0 inches), providing sturdy support for walking and standing. These precise measurements highlight the bird’s adaptability and efficiency in its natural habitat, showcasing the evolution of its physical traits to optimize survival and functionality.

European Presence

The American herring gull, specifically the smithsonianus subspecies, is notably represented in Europe, particularly in its first-winter plumage. Over 90% of smithsonianus sightings in Europe are of these young birds. In Ireland, for instance, where the local herring gulls are typical of the paler argenteus type, the first-winter smithsonianus stands out quite conspicuously among mid-winter gull flocks.

Their darker, more distinct plumage makes them easy to identify, even from a distance. This difference in appearance highlights the diversity within the species and the various adaptations that have arisen due to geographical distribution. The presence of smithsonianus in Europe also indicates migration patterns and the ecological interactions between different gull populations across the Atlantic.

Individual Variation of Smithsonianus

The smithsonianus subspecies exhibits a remarkable level of individual variation, particularly when compared to the argenteus subspecies of the same age. This variability presents challenges in identifying birds, especially when searching for them amidst gull flocks on the European side of the Atlantic. Unlike the relatively uniform appearance of European Herring Gulls, juvenile smithsonianus can display a wide range of characteristics, making them stand out among their counterparts.

Key Identification Features

While many characteristics of juvenile smithsonianus and European Herring Gulls remain consistent, such as those related to their upper- and undertail-coverts, wings, and tail, there are additional features to consider when attempting to identify a potential first-winter smithsonianus.

Uniformity of Underparts

By mid-winter, first-year smithsonianus may exhibit slight fading and less uniform darkness compared to their appearance as juveniles. However, they still tend to maintain a greater level of uniformity across their underparts compared to European Herring Gulls. While European Herring Gulls often display paler, more mottled, or streaked underparts, first-winter smithsonianus can appear more uniform, thereby appearing darker overall. This uniformity is a key distinguishing feature between the two subspecies.

Consistent Darkness on Hindneck and Mantle

Another characteristic to observe is the level of darkness on the lower hindneck and upper mantle. Smithsonianus individuals may display a more uniformly brownish hue in these areas, seamlessly blending with their uniform underparts. This stable darkness contrasts with the potentially more varied appearance seen in European Herring Gulls, aiding in the differentiation between the two subspecies. These subtle distinctions in coloration and patterning play a crucial role in accurately identifying smithsonianus individuals within mixed gull populations.

Post-Juvenile Plumage Transition

During the post-juvenile molt of body feathers, first-winter smithsonianus undergo a significant change in their plumage. One notable transformation is the acquisition of plain, slate-grey feathers on the breast-sides and flanks, which gradually extends to the rest of the underparts.

This change in coloration contrasts starkly with their previous plumage, contributing to their overall appearance as they transition into adulthood. In contrast, European Herring Gulls undergoing the same molt exhibit a more subtle contrast between their old, brownish feathers and the new, greyish ones, likely due to their naturally more mottled underparts.

Breeding Adult Plumage

Breeding adults of the American herring gull display distinctive plumage characteristics. They feature a white head, rump, tail, and underparts, creating a striking contrast with their pale grey back and upper wings. The wingtips are adorned with black markings interspersed with white spots, often referred to as “mirrors,” while the trailing edge of the wing is marked with white. Beneath, the underwing appears greyish, with dark tips on the outer primary feathers, contributing to the bird’s overall appearance in flight.

Leg, Feet, Bill, and Eye Coloration

The American herring gull exhibits specific coloration in its legs, feet, bill, and eyes. Typically, the legs and feet are pink, though they may sometimes display a bluish tinge or, infrequently, appear yellow. The bill of the American herring gull is distinctive, being yellow with a crimson spot on the lower mandible, adding a splash of color to its appearance. The eyes of the bird are bright, ranging from pale to medium yellow, often encircled by a bare yellow or orange ring. During the winter months, the head and neck may become streaked with brown, adding further variation to its appearance.

First-Winter Plumage

First-winter American herring gulls typically exhibit a predominantly gray-brown coloration. They have a dark tail and a brown rump adorned with dark bars. Their outer primaries are dark, contrasting with the paler inner primaries. Additionally, they possess dark eyes and a dark bill, which may develop a lighter base as the winter progresses. Often, the head appears slightly paler than the body, adding to the overall variability of their appearance during this stage.

Smithsonian/American Herring Gull: Profile, Traits, Facts, Range

Second-Winter Plumage

By the second winter, American herring gulls begin to undergo noticeable changes in their plumage. Their eyes may lighten, and their bills start to show signs of transition, featuring a pale base with a black tip. The head also tends to lighten in color, further distinguishing them from their first-winter counterparts. Additionally, hints of gray feathers begin to emerge on the back, marking the gradual progression towards adult plumage.

Third-Winter Plumage

Third-winter American herring gulls are closer in appearance to adults but still retain some remnants of their juvenile plumage. While the black coloration on the bill may diminish, traces of it can still be present. Similarly, patches of brown may persist on the body and wings, indicating ongoing maturation. Notably, a black band on the tail becomes visible in American herring gulls of this age, serving as a distinctive feature during identification.

Vocalizations

The American herring gull may lack a melodic tune, but it compensates with a diverse array of cries and calls. Among these, the “long call” stands out, characterized by a series of notes accompanied by a distinctive dipping and raising motion of the head. Another notable vocalization is the “choking call,” typically heard during courtship displays or territorial disputes. Additionally, juvenile birds emit high-pitched plaintive cries, signaling their need for feeding from a parent. They may also produce a clicking distress call when a parent abruptly departs, expressing their anxiety or distress.

Pale-headed Appearance

In late winter, many smithsonianus individuals develop a pale head, primarily due to wear and tear. This feature, particularly against their dark body, can make them stand out within a flock of European Herring Gulls. However, while this characteristic has been highlighted, it is essential to note that only a small percentage of smithsonianus birds exhibit a pale head. Moreover, darker-bodied European birds may occasionally appear pale-headed for similar reasons. Interestingly, European Herring Gulls from the eastern Baltic region often display a strikingly pale-headed appearance during winter.

Scapular Patterns

The scapular markings of first-winter birds pose a challenge in identification due to the extensive individual variation exhibited by both smithsonianus and European Herring Gulls. This variation, combined with the overlapping nature of their patterns, complicates the identification of unique patterns. Consequently, distinguishing between the two subspecies based solely on scapular markings becomes exceedingly difficult. The wide range of variations within this feature underscores the complexity of gull plumage and the nuances involved in species differentiation.

Distinctive Scapular Patterns in Smithsonianus

While both smithsonianus and European Herring Gulls display characteristic scapular patterns, there are certain patterns that are more commonly observed in the former. It’s crucial to differentiate between the typically retained juvenile scapulars, which are often plain, brownish, and somewhat worn with pointed tips, and the freshly molted first-winter feathers, which have broader, more rounded tips.

Characteristic Patterns

Among smithsonianus, the most distinctive scapular patterns, usually observed among the larger rearmost and lower rows of feathers, are moderately dark and plain, with or without a diffuse darker center. These patterns stand out due to their consistent appearance and unique markings, contributing to the overall identification of smithsonianus individuals.

Variation in Scapular Patterns

One notable aspect of scapular patterns in smithsonianus is the variability observed within individual birds. This variability is attributed, in part, to the post-juvenile molt process, which can be a relatively prolonged affair. As a result, a single bird may exhibit a variety of scapular patterns, reflecting the timing and progression of its molt. This contrasts with European Herring Gulls, where the pattern of first-winter scapulars tends to be more consistent, with each feather displaying similar markings.

Consistency in European Herring Gulls

In contrast to the variability observed in smithsonianus, most European Herring Gulls display a relatively consistent pattern in their first-winter scapulars. Each feather typically exhibits similar markings, creating a series of regular transverse pale and dark bars. This consistency in pattern contributes to the overall uniformity observed in European Herring Gulls, making them distinguishable from their American counterparts.

Underwing-Coverts

One striking characteristic in smithsonianus is the uniformity of the axillaries and underwing-coverts, often exhibiting a “smoky” appearance without apparent patterning. In contrast, argentatus and argenteus typically display paler tones and more mottled textures in these areas. While the underwing-coverts of graellsii may resemble those of smithsonianus, several other differences usually prevent serious confusion between the two subspecies.

Bill Pattern

Both smithsonianus and argentatus tend to develop a pale base to the bill relatively early in their first winter, resembling first-year Glaucous Gulls to some extent. However, in argenteus, the contrast in bill pattern tends to be more subdued until later in the winter.

Adult European Herring Gulls

Adult European herring gulls closely resemble American herring gulls, with the subspecies L. a. argenteus being smaller than many American birds, while those of the northern subspecies L. a. argentatus are typically darker grey above. Notably, European birds lack the long grey tongues on the sixth, seventh, and eighth primaries and solid black markings on the fifth and sixth primaries, which are characteristic of American Herring Gulls.

First-Winter European Birds

First-winter European birds exhibit more checkered upperparts, streaked underparts, and a paler rump and base to the tail compared to their American counterparts. These differences contribute to the overall distinction between European and American Herring Gulls at various stages of development.

Breeding Distribution

The American herring gull’s breeding range spans the northern part of North America, extending from central and southern Alaska to the Great Lakes and the northeast coast of the US from Maine south to North Carolina. It breeds across most of Canada, excluding the southwest and Arctic regions. Nesting sites are typically found near water bodies, including coasts, islands, and cliffs, with some birds also nesting on rooftops in urban areas.

Year-Round Distribution

While the American herring gull is present year-round in southern Alaska, the Great Lakes, and the northeast USA, most individuals migrate southward for the winter, extending as far as Mexico. Some birds also reach Hawaii, Central America, and the West Indies during this time. Vagrants have been recorded in Colombia and Venezuela, with occasional sightings reported in Ecuador and Peru.

European Records

The first European record of an American herring gull dates back to 1937 when a bird ringed in New Brunswick was caught on a ship in Spanish waters. Since 1990, numerous sightings have been reported from Western Europe, with the first British record occurring in 1994 in Cheshire. These records indicate occasional occurrences of American herring gulls venturing beyond their typical range.

Habitat and Feeding Behavior

American herring gulls are adaptable in their choice of habitat for both nesting and feeding. They typically nest in colonies near water bodies but can also be found nesting on rooftops in urban areas. They feed at sea and on various terrestrial habitats, including beaches, mudflats, lakes, rivers, fields, and refuse dumps. After feeding, they often roost in open areas near their feeding sites, demonstrating their opportunistic feeding behavior and ability to exploit diverse food sources.

Diverse Dietary Habits

The American herring gull exhibits a diverse array of dietary habits, showcasing remarkable adaptability in its food choices. Its menu includes a plethora of options, ranging from marine invertebrates such as mussels, crabs, sea urchins, and squid to various fish species like capelin, alewife, and smelt. Additionally, it doesn’t shy away from consuming insects and scavenging on other birds, including their chicks and eggs. This broad spectrum of dietary preferences underscores the gull’s opportunistic feeding behavior, enabling it to thrive in various coastal environments.

Versatile Feeding Strategies

When it comes to acquiring food, the American herring gull employs a range of techniques, showcasing its versatility and adaptability. While carrion and human refuse serve as readily available sources of sustenance, the gull is also adept at foraging along the shorelines and diving into the water to catch prey. It utilizes both surface dipping and shallow plunge-diving methods to secure its meals, demonstrating a keen hunting prowess honed through evolution. Fitness – Meditation – Diet – Weight Loss – Healthy Living – Yoga

Unique Feeding Behavior

One intriguing aspect of the American herring gull’s feeding behavior is its consumption of clams and mussels. Rather than relying solely on brute force to crack open their shells, the gull has developed a distinctive technique. It employs gravity as its ally, dropping these hard-shelled delicacies from a height onto solid surfaces such as roads or rocks. This behavior raises questions regarding its origin, prompting debates among researchers about whether it’s a learned behavior or an innate instinct passed down through generations.

Mating Rituals and Nesting Habits

During the months of March or April, the American herring gull partakes in the elaborate rituals of courtship and pair formation. The nest, a simple scrape on the ground, is meticulously adorned with vegetation like grass, seaweed, and feathers, providing a cozy incubation chamber for the eggs to come. Typically, the female lays three eggs over a span of four to six days, initiating the incubation process which lasts for approximately 30 to 32 days from the laying of the second egg.

Parental Care and Developmental Milestones

Upon hatching, the young gulls, known as chicks, are nurtured and cared for by both parents. The fledging period lasts between six to seven weeks, during which the chicks grow and develop under the watchful eyes of their attentive guardians. Even after leaving the nest, the juveniles receive supplementary feeding in the surrounding area for several more weeks. This extended period of parental care ensures the fledglings’ survival and gradual independence as they mature.

Social Dynamics and Pair Bonding

Within the American herring gull population, a spectrum of social dynamics is observed. While some pairs exhibit a strong, enduring bond, remaining nearby year-round, others display a more independent demeanor. Despite potential variations in mating habits, many gulls tend to reunite with the same partner each breeding season, forming a sense of continuity amidst the ever-changing rhythms of nature. Bird accessories on Amazon

Status

The American herring gull species grew to become fairly uncommon through the 19th century when it was hunted for its eggs and feathers. From the 1930s to the 1960s, it was quickly attributable to safety from searching, elevated waste from fisheries to feed on, and fewer competitors for small fish and invertebrates as people diminished the populations of enormous fish, whales, and pinnipeds (seals). The numbers of the American herring gull leveled off through the 1970s and 80s and should now be declining in some areas.

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