What kind of bird is the starfish? We will explain its characteristics, ecology, and habitat. The white-crowned nighttail has a very distinctive red head and is a bird that can mainly be seen in Europe. In winter, this bird appears in northern Africa and the Middle East, but it is actually an endangered species.
What is a starfish? About basic status
The white-crowned nighttail is a bird classified in the Anseriformes order, Anseriformes family, and the Anseriformes genus. The kanji is Hoshiba Shiro, and the scientific name is Aythya ferina. The total length is 42-49cm, the wingspan is 72-82cm, and the weight is 0.5-1kg. The list of information is as follows.
| Japanese（和名） | ホシハジロ |
| English（英名） | Common pochard Eurasian pochard European pochard |
| scientific name(学名) | Aythya ferina |
| classification（分類） | Ave、 Anseriformes、Anatidae、Aythya 鳥綱、カモ目、カモ科、ハジロ属 |
| IUCN Status(保全状況) | VULNERABLE |
| Length（全長） | 42-49cm |
| Weight（体重） | 0.5-1kg |
Taxonomy of the Common Pochard
The Common Pochard is a bird and a type of freshwater duck belonging to the Anseriformes order.
| 分類階層 | 名称 |
|---|---|
| 界 (Kingdom) | Animalia（動物界） |
| 門 (Phylum) | Chordata（脊索動物門） |
| 綱 (Class) | Aves（鳥綱） |
| 目 (Order) | Anseriformes（カモ目） |
| 科 (Family) | Anatidae（カモ科） |
| 属 (Genus) | Aythya（アカハジロ属） |
| 種 (Species) | Aythya ferina（ホシハジロ） |
About habitat
The white-crowned nighttail is distributed mainly in Europe.
- Global Distribution
The Common Pochard is a migratory bird found widely distributed mainly in Eurasia.
Breeding Grounds (Summer):
Northern Europe, northwestern Russia to southern Siberia
Breeds in wetlands, freshwater lakes, and around rivers.
Wintering Grounds (Winter):
Western Europe (UK, France, the Netherlands, etc.)
Middle East, India, East Asia (China, Japan, the Korean Peninsula)
Also winters in shallow coastal lakes, estuaries, and bays.
- Habitat in Japan
Migratory Period: Mainly October to March
Main Wintering Grounds:
Lakes and marshes in Hokkaido and the Tohoku region
Large ponds and rivers in the Kanto, Chubu, and Kinki regions
Also observed in tidal estuaries and bays.
Behavior:
Often lives in groups.
Dives to feed on aquatic plants and aquatic organisms.
- Habitat Characteristics
Water Type:
Freshwater lakes, rivers, ponds, and wetlands
Can also be found in shallow bays and brackish waters in winter
Water Quality and Depth:
Prefers relatively calm, shallow waters
Vegetation:
Areas with abundant aquatic plants and algae
Environments with an abundance of aquatic insects and small fish to feed on
feature is? What kind of creature is it?
The male white-tailed flycatcher has reddish-brown plumage from the head to the neck, and the feathers covering the chest plumage and the base of the tail feathers are black. Female irises are brown. The white-crowned nighttail is quite widespread in Europe, and in winter it spends the winter in northern Africa, the Middle East, and India. White-crowned nighttails live in lakes, rivers, estuaries, and inner bays.
- Appearance
Male
Head: Reddish-brown and shiny
Chest: Black
Back and Wings: Gray
Eyes: Yellow
Bright, eye-catching coloring throughout
Relatively vivid even in winter plumage
Female
Overall: Subdued brown coloring
Chest and back: Shades of brown
Eyes are slightly darker than those of the male
From a distance, it appears to be an ordinary brown duck
Common
Body Length: Approximately 45-50 cm (medium-sized duck)
Wingspan: Approximately 70-80 cm
A diving duck with a rounded body that excels at floating in water
- Ecology & Behavior
Diet
Mainly forages by diving
Aquatic plants, algae, small fish, crustaceans, aquatic insects, etc.
Diet changes depending on the season and location
Habitat
Lakes, ponds, estuaries, wetlands, shallow inland bays
In winter, they form flocks, with groups of dozens to hundreds of birds
Breeding
Breeding season (spring-summer) takes place in northern wetlands and lakes
Nests are built in grassy patches or floating islands near the water’s edge
Lays 8-12 eggs per breeding
Flight & Migration
Excellent migratory birds, traveling long distances
Flying in a straight, fast flight, often near the water’s surface
- Personality & Characteristic Behavior
Generally timid, but calm when in a flock
They are characterized by their diving to search for food at the surface in winter
During the breeding season, the male’s reddish-brown head becomes brighter, attracting females
What does the ecology look like?
The starfish is a herbivorous diet, subsisting on seeds, leaves, buds, underground stems, fish, and amphibians. The reproductive form is oviparous. They build nests made of reeds piled up in bushes near water or on top of aquatic plants floating on the water’s surface. The female lays 8-10 eggs and incubates them. The lifespan is about 20 years.
- Diet/Foraging Behavior
Diving Ducks
They dive underwater to feed on aquatic plants, algae, small fish, crustaceans, shellfish, and insects.
Foraging Method
They submerge their bodies and dive to grab plants and animals from the bottom.
Time of Day
They also forage during the day, but often move in groups, ensuring safety.
- Breeding
Breeding Season: Spring to Summer (Northern Breeding Grounds)
Nests:
They build nests on the water’s edge of lakes and marshes, floating islands, and grassy areas.
They prefer locations slightly above the water surface.
Eggs: Approximately 8-12 per clutch
Rearing:
Females are responsible for incubation and raising the eggs.
Chicks begin swimming immediately after hatching and grow by feeding on small aquatic animals and plants.
- Migration/Migration
They are migratory birds, traveling between breeding and wintering grounds.
Migration Distances: Can be thousands of kilometers.
Wintering areas: Japan, western Europe, India, East Asia, etc.
They often travel in flocks, ensuring safety while flying.
- Sociality/Flocking
They often form flocks in winter.
They can form large flocks of dozens to hundreds of birds.
They dive to feed while checking each other’s positions within the flock.
Both males and females mingle with the flock outside of the breeding season.
- Habitat and Adaptation
They prefer shallow waters such as freshwater lakes, ponds, estuaries, and marshes.
They can adapt to tidal estuaries and inland bays.
They have the flexibility to change their feeding locations depending on water quality and the presence of aquatic plants.
Are there any natural enemies?
The nests of white-tailed hawks are often raided by eagles and hawks.
About Common Pochard Chicks
This article provides detailed information on the characteristics and ecology of Common Pochard (Aythya ferina) chicks (young birds).
- Birth and Early Life
Hatching Period: Spring to Early Summer (at breeding grounds)
Number of Eggs: Approximately 8-12 per clutch
Incubation Period: Approximately 23-25 days (female incubates)
- Appearance
Plumage: Newly hatched chicks have fluffy, soft down feathers with mottled yellow and brown patterns.
Inconspicuous Coloration: Their overall coloring is dull to protect them from predators.
Body Shape: Small and round, but adapted for swimming and diving.
- Behavior and Abilities
Swimming: Able to swim immediately after birth.
Diving: Diving ability develops gradually.
Foraging: Initially guided by the female, they peck at small animals and aquatic plants in the water.
Alert Behavior: They maintain safety within the flock while being protected by their mother.
- Growth
Flight Ability: They become capable of flight at approximately 50-60 days of age.
Molt: Their newborn down is replaced by adult feathers.
Independence: Once they are able to fly, they can forage independently from their parents.
- Biological Characteristics
Chicks quickly adapt to aquatic life.
They gradually learn the skill of diving forage from an early stage of development.
The mother and her flock defend against predators (crows, raptors, small terrestrial predators).
Is the white-crowned nighttail designated as an endangered species?
The white-crowned nighttail is designated as an endangered species. Their population has declined dramatically due to changes in their natural habitat and overhunting. In Europe, this decline rate is 30-49% over 20 years, which is a very serious situation.
- International Status (IUCN)
IUCN Red List: Least Concern (LC)
Reason:
Relatively large population and widespread distribution.
Population declines have been reported in some areas, but overall the species is stable.
- Status in Japan
Not designated as a specially endangered species in Japan.
The number of migratory winter birds is stable, but attention must be paid to habitat loss due to lake reclamation and development.
- Precautions and Need for Protection
Habitat Conservation:
Deterioration of lake and wetland environments will reduce the number of wintering flocks.
Capture/Hunting:
No significant impact if properly managed.
Impact as a Migratory Bird:
Environmental changes in wintering and stopover areas may affect populations in the long term.
Can starfish be kept as pets?
It would be difficult to raise a starfish. It is designated as an endangered species, and its population is declining rapidly.
- Basic Pet Ownership
The Common Pochard is a wild migratory bird and is generally not sold as a pet.
Capturing and selling it in Japan may be restricted by law.
While not subject to regulation under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), capturing wild specimens is generally prohibited under the Wildlife Protection Act.
Keeping them as pets is limited to breeding specimens or those bred in specialized facilities.
- Difficulty of Keeping
Requires a large water area
Because they dive, they require a deep pond or large aquarium with a large water surface.
Prefers to live in groups.
They are prone to stress when kept alone.
Diet
They require aquatic plants, small fish, and crustaceans, making food preparation difficult.
Winter Care
As they are migratory birds, they are sensitive to temperature and sunlight.
They have excellent flying ability.
They require large measures to prevent them from jumping out (such as a large enclosure or net).
- Overall Evaluation
Sea Pochards are not suitable as pets.
Keeping them is extremely difficult, requiring specialized knowledge and equipment.
Keeping them in the home is not practical, and observing them in the wild is the best way to interact with them.
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