The Belted Kingfisher (Megaceryle alcyon) is a medium-sized bird found across North America. It is the only member of the kingfisher family found in most of North America. The Belted Kingfisher has several distinctive physical features that help it thrive as a fisher.
Size and Weight
The Belted Kingfisher has an average length of 11-14 inches (28-35 cm) with a wingspan of 18-21 inches (45-53 cm). It weighs between 113-178 grams (4-6 oz). The female kingfishers are larger than the males. Females average 128 grams compared to 117 grams for males.
The kingfisher has a large head relative to its body size. This allows it to have strong jaw muscles to catch fish. The long, dagger-like bill is 2-3 inches (5-8 cm) and suited for spearing fish. The wings are rounded which provides excellent maneuverability for diving and fishing.
Plumage
The Belted Kingfisher has a slate-blue head, back, wings and tail. The breast is white. Females have a rusty band across the upper belly. Juveniles are similar but have white flecking on the head and back. The white collar around the neck gives the kingfisher its “belted” name.
The blue-gray plumage provides camouflage when the kingfisher is perched over water. The white underside helps break up the bird’s outline when observed from below. The blue feathers are iridescent due to light refracting structures in the feathers. This iridescence is especially noticeable in bright sunlight.
Blue Plumage
There are two main types of blue pigment that contribute to the Belted Kingfisher’s blue plumage:
- Melanin – This provides the darker blue-gray color
- Structural color – Microstructures in the feathers refract light to produce a bright blue iridescence
The combination of these two blue colors gives the bird its distinctive blue shade.
Legs and Feet
The Belted Kingfisher has short legs with four toes – three pointing forward and one pointing back. The toes have sharp claws which allow the bird to grasp fish and perch on branches overhanging water.
The legs and feet are a reddish-orange color. The legs are set far back on the body to provide strength and balance for perching upright on branches.
Body Part | Adaptation |
---|---|
Legs | Short and strong for perching on branches |
Toes | 3 front, 1 back; claws for grasping fish and perching |
Color | Reddish-orange |
Beak
The Belted Kingfisher has a long, pointed beak that measures 2-3 inches (5-8 cm). The beak is black with a gray base. It is ideally shaped for spearing and catching fish.
The upper mandible has a notch near the tip which helps secure fish against the bird’s body. The lower mandible has a groove to match the upper notch.
Kingfishers have extra bones in the beak which provide strength. Special joints in the beak absorb the impact of hitting the water when diving for fish.
Beak Adaptations
Feature | Adaptation |
---|---|
Long & dagger-like | Spearing fish |
Notch & groove | Gripping fish |
Extra bones | Strength for hitting water |
Flexible joint | Absorbing diving impact |
Vision
Belted Kingfishers have large eyes adapted for hunting fish. The eyes are set widely apart on the sides of the head for a wide field of view above and below the water.
Kingfishers can focus both eyes forward to precisely locate prey. The eyes have special lenses that allow them to accommodate both air and water.
Like other kingfishers, they are believed to have tetrachromatic vision. This allows them to see ultraviolet wavelengths of light invisible to humans.
Vision Adaptations
Trait | Function |
---|---|
Large eyes | Spotting fish prey |
Widely spaced | Wide field of view above/below water |
Accommodating lenses | Focus in air and water |
Tetrachromatic | See ultraviolet light |
Wings and Tail
The wings of the Belted Kingfisher are rounded with eleven primary flight feathers. The rounded shape allows excellent maneuverability for diving and flying around obstacles.
The short tail has twelve stiff feathers that the kingfisher uses as a rudder when flying. The tail helps the bird make quick turns in pursuit of fish.
The wingspan ranges from 18-21 inches (45-53 cm). The wings provide enough power to propel the kingfisher to speeds up to 35 mph when diving for fish.
Wing and Tail Adaptations
Feature | Function |
---|---|
Rounded wings | Maneuverability |
11 primary feathers | Powerful flight |
Stiff tail | Rudder for quick turns |
18-21 inch wingspan | Speeds up to 35 mph |
Calls
Belted Kingfishers make a loud, rattling call described as a “chake-ake-ake-ake-ake-ake.” They make this call year-round to defend territories and during courtship.
The kingfisher also makes a series of high-pitched squeaks or whistles during courtship or when feeding young. Juveniles make begging calls when asking for food.
The rattling territorial/courtship call carries well over long distances. This helps the kingfisher communicate across its habitat.
Kingfisher Calls
Call Type | Purpose | Description |
---|---|---|
Territorial & courtship call | Defend territory, court mate | Loud “chake-ake-ake” rattle |
Feeding call | Communication at nest | Squeaks and whistles |
Begging call | Juvenile food request | High-pitched squeaking |
Male vs Female
Male and female Belted Kingfishers are similar in overall appearance but some key physical differences exist:
- Females are larger – Average 128 grams vs 117 for males
- Females have rusty band on upper belly, males do not
- Female’s bill averages around 5 mm longer
- Female’s wings average 5% longer than males
- Females have extra bones in the skull for bill muscle attachment
The size differences relate to the female’s role in preparation of the nest. The female uses her larger bill to excavate nesting tunnels in creek banks. Her larger wings provide more power for digging and carrying heavy loads of dirt.
Juvenile Plumage
Juvenile Belted Kingfishers resemble the adults but have some key differences:
- White flecking on head and back feathers
- Breast band is diffuse gray instead of clean white
- Belly stripe on females is less distinct
- Iris of eye is olive-gray instead of red-brown
- Legs and feet are darker gray rather than orange
Within a few months of leaving the nest, juveniles molt into adult plumage. By one year old they are indistinguishable from adults in the field.
Conclusion
In summary, the Belted Kingfisher has a variety of specialized physical features and adaptations that aid its fishing lifestyle, including:
- Large head and eyes
- Long, dagger-like bill
- Short legs with sharp claws
- Compact, rounded wings
- Stiff rudder-like tail
- Blue-gray camouflage plumage
- UV-enhanced vision
- Powerful rattling territorial call
The kingfisher’s body is engineered for its piscivorous habits. It can spot fish from a perch, plunge dive at high speeds, grasp prey with its bill, and return to a perch to eat – all skills powered by its specialized physical features.