Introduction to The Eastern Marsh Harrier UPSC

Welcome to PreCrack! Recently, Eastern Marsh Harrier was in the news because a birder in Chennai, R Karthik, spotted the rare migratory bird at Madurantakam lake, marking the first sighting of its kind in the region.

Why Eastern Marsh Harrier is in the News?

The Eastern Marsh Harrier is making headlines as birder R Karthik spotted this rare migratory bird at Madurantakam lake near Vedanthangal in Chennai.

What is the Eastern Marsh Harrier?

The eastern marsh harrier (Circus spilonotus) is a bird of prey, belonging to the marsh harrier group. Initially thought to be the same as the western marsh harrier, it is now considered a separate species. With two subspecies – C. s. spilonotus in eastern Asia and C. s. spilothorax (Papuan harrier) in New Guinea – it displays distinct characteristics.

About Madurantakam Lake

Madurantakam Lake, also called Madurantakam aeri, is a significant body of water spread over 2400 acres in Madurantakam, Tamil Nadu, India. It holds the title of the second largest artificial lake in the state.

Details about Eastern Marsh Harrier

We have added all details about Eastern Marsh Harrier below-

About

The Eastern Marsh Harrier (Circus spilonotus) is a raptor in the marsh harrier group, initially thought to be the same as the Western Marsh Harrier but now classified as a distinct species.

Description about Eastern Marsh Harrier

The Eastern Marsh Harrier is about 48 to 58 cm long, with a wingspan of 113 to 137 cm. The females are usually bigger than the males.

Scientific Facts

Scientific Name of the Eastern Marsh Harrier

Scientific name of the Eastern Marsh Harrier is Circus spilonotus).

Other Scientific Facts

The Eastern Marsh Harrier is scientifically classified under the Animalia kingdom, Chordata phylum, Aves class, and Accipitriformes order. It belongs to the Accipitridae family and Circus genus, with the specific name Circus spilonotus.

This bird, marked as “Least Concern” by the IUCN, boasts a stable population. Its habitat spans the Eukaryota domain. These scientific facts illuminate the Eastern Marsh Harrier’s taxonomic position, emphasizing its avian nature. The “Least Concern” status reflects positive conservation prospects for this species, assuring its well-being at the time of assessment.

Significance

The Eastern Marsh Harrier holds significance in various ways:

Ecological Significance

• Predator-prey balance: As apex predators, they control small mammal, reptile, and amphibian populations, maintaining a balanced ecosystem.
• Seed dispersal: Carrying seeds during hunting, they contribute to plant diversity by dropping them across their territory.

Cultural Significance

• Indicator of healthy wetlands: Their presence signals a thriving wetland ecosystem, rich in prey and suitable for diverse birdlife.
• Aesthetic value: Admired for their graceful flight and unique plumage, they are a delight for birdwatchers and nature enthusiasts.

Scientific Significance

• Biodiversity indicator: Their role as top predators reflects overall wetland health, aiding in ecosystem assessments.
• Contribution to conservation: Studying them informs efforts to protect wetland birds and habitats, addressing ecological needs and threats.

Origin

The exact beginnings of the Eastern Marsh Harrier are a bit mysterious due to ongoing research. Scientists believe its group, called Circus, emerged in Eurasia about 23 million years ago during the Miocene epoch, based on genetic and fossil clues.

Habitat

The Eastern Marsh Harrier prefers open country with dense vegetation for its habitat. Here’s a breakdown of its preferred dwelling places:

Wetlands: This is their primary habitat, including:

• Marshes: These are areas of shallow water dominated by reeds, sedges, and other emergent vegetation.
• Swamps: These are forested wetlands with standing water and various tree species depending on the region.
• Bogs: These are acidic, waterlogged areas with sphagnum moss and other low-growing vegetation.
• Rice paddies: These flooded fields are an attractive habitat during breeding and migration seasons.

Other Open Areas: The Eastern Marsh Harrier can also be found in:

• Grasslands: These areas provide hunting grounds, especially if they border wetlands or other open habitats.

Diet

Diet of the Eastern Marsh Harrier:

Main Prey (The primary or most important types of animals)

• Small Mammals: Rodents like voles, mice, rats, as well as rabbits, shrews, and moles.
• Birds: Targets small to medium-sized birds, especially chicks, eggs, or vulnerable individuals. Examples include ducks, rails, waders, and marsh passerines.

Secondary Prey (Less preferred types of animals that the Eastern Marsh Harrier may hunt)

• Reptiles: Occasionally consumes lizards and snakes, especially smaller ones.
• Amphibians: Frogs are part of their diet, especially where abundant.
• Invertebrates: Opportunistically consumes insects like grasshoppers and beetles.

Carrion (Fresh flesh of dead animals)

• Scavenging: May scavenge on carrion, from small rodents to larger herbivores, especially during harsh winter months with lower prey availability.

Hunting Techniques

• Low, Buoyant Flight: Flies low in a shallow V-shape, scanning the ground for prey.
• Surprise Attack: Utilizes a quick dive to catch unsuspecting prey on the ground or in shallow water.
• Sensory Skills: Excellent hearing and vision help locate hidden prey in dense vegetation.

Behavior

We can understand the behavior of this bird named Eastern Marsh Harriers by these following points-

1. Solitary Nature

• Alone Time: Usually, Eastern Marsh Harriers like being by themselves, especially when not breeding. They have their own territories and mostly interact with others during courtship and nesting.

2. Hunting Habits

• Low, Sneaky Flight: They fly close to the ground in a V-shape, staying hidden while looking for food.
• Surprise Attacks: Love surprising prey by quickly diving down to catch them on the ground or in shallow water.
• Eat What’s Around: They’re flexible eaters, choosing their meals based on what’s available. Their sharp eyesight and hearing help them find and catch different types of prey.

3. Breeding Behaviour

• Show Off for Love: During breeding season, males do fancy flying displays to impress potential mates, with cool moves and calls.
• Home Construction: Females build nests on the ground, using sticks, reeds, and grass. They like cozy spots in their territory with lots of plants.
• Parent Teamwork: Both parents take turns sitting on the eggs and taking care of the chicks after they hatch. Teamwork is important!

4. Talking and Moving

• Occasional Chit-Chat: While they’re usually quiet, they do make some sounds, like a mewing call, especially at resting spots, and territorial calls during the breeding season.

5. Migration

• Winter Travel: Most Eastern Marsh Harriers are like snowbirds—they move to warmer places for winter. After breeding in eastern Asia, they head south to spots like southern China, Taiwan, Korea, and Southeast Asia.

Taxonomy

The Eastern Marsh Harrier belongs to the following taxonomic classification:

• Kingdom: Animalia
• Phylum: Chordata
• Class: Aves (Birds)
• Order: Accipitriformes (Accipiters, Hawks, Eagles, and Kites)
• Family: Accipitridae (Hawks, Eagles, and Kites)
• Genus: Circus (Harriers)
• Species: Circus spilonotus

Here is the simplification of each level of classification-

1. Kingdom: Animalia refers to all animals, including humans.
2. Phylum: Chordata encompasses animals with a backbone or notochord, including vertebrates and some primitive chordates.
3. Class: Aves represents all birds, distinguished by feathers, wings, beaks, and warm-bloodedness.
4. Order: Accipitriformes includes birds of prey like hawks, eagles, kites, and harriers, known for their sharp talons and hunting prowess.
5. Family: Accipitridae groups together various hawks, eagles, and kites with similar characteristics, including powerful beaks and talons.
6. Genus: Circus refers specifically to the Harriers, a group of slender-bodied, long-winged birds of prey known for their low, gliding flight and hunting style.
7. Species: Circus spilonotus denotes the Eastern Marsh Harrier as a unique species within the Circus genus, distinguished from other harriers by its specific physical features, behaviors, and geographical distribution.

Reproduction

The reproduction of Eastern Marsh Harriers consist of these following steps or points –

1. Breeding Season

The Eastern Marsh Harrier’s reproductive phase occurs primarily between April and June within its primary range across eastern Asia.

2. Courtship (Just before mating)

During courtship, males tries to attract females with great flying-show, such as dives, rolls, and acrobatic styles while vocalizing to attract potential mates.

3. Nesting

Females construct ground nests in dense vegetation, utilizing materials such as sticks, reeds, and grasses within their territorial domain.

4. Clutch Size (Eggs)

Each reproductive cycle results in a clutch of 4-7 eggs, typically characterized by a bluish-white hue with discernible brown markings.

5. Incubation

Incubation responsibilities are shared between both parents, with a duration ranging from 33 to 48 days.

6. Hatchlings(baby come out of eggs)

When babies are born, they can’t see, and they’re very tiny and fluffy. Both mom and dad take care of them and feed them.

7. Fledging

Around 35-40 days post-hatching, the fledging phase occurs, marking the development of flight training and the departure from the nest. Despite this, juvenile dependency on parental care may persist for a certain duration.

Range / Distribution

The range of Eastern Marsh Harriers sometime depends on the need of their living reason. This may include place for living, for reproduction, for eating and more. We have added all of these classification below-

Breeding Home

In eastern Asia, which is a big place that includes northeast China, Mongolia, and southeast Siberia. They also have small groups in northern Japan, specifically in Hokkaido and northern Honshu.

Winter Vacation

For the winter, most of them take a long trip south to escape the cold where they breed. They go to places like southern China, including islands like Hainan, and various countries in Southeast Asia like Vietnam, Thailand, Malaysia, and the Philippines.

Vacation Spots

They also like spending their winter in other places like Taiwan, Korea, and even parts of northeast India and Bangladesh.

Home Preferences

They love living in open places with lots of plants, especially wetlands like marshes, swamps, and rice paddies. They’re also cool with grasslands, salty areas (called saltpans), and spots near water with low plants.

Conservation Status

The Eastern Marsh Harrier holds a “Least Concern” conservation status, reflecting a stable population with no immediate threat of extinction. Although considered promising currently, ongoing monitoring and conservation efforts are crucial to safeguard its habitat and address potential challenges in the ever-changing environmental landscape.

Threats to the Eastern Marsh Harrier

These are the key threats (Potential) to the Eastern Marsh Harriers0

1. Habitat Loss: Drainage, agricultural intensification, and urbanization reduce suitable wetland habitats crucial for breeding and foraging.
2. Pesticide Use: Agricultural pesticides can contaminate prey, adversely affecting the Eastern Marsh Harrier and other species in its food chain.
3. Climate Change: Altered weather patterns and rising temperatures may impact prey availability and overall wetland ecosystems.
4. Wetland Degradation: Pollution and human activities degrade wetlands, diminishing the quality of the harrier’s habitat.
5. Human Disturbance: Increased human activities, such as recreation and disturbance at nesting sites, can disrupt breeding and feeding behaviors.

Latest News on Eastern Marsh Harrier

In a rare discovery, Chennai birder R Karthik recently spotted the Eastern Marsh Harrier at Madurantakam lake near Vedanthangal. The bird, usually found in South Korea and Taiwan, made its first appearance in the region. Karthik, an experienced birder, photographed the migratory harrier during its dusk roosting.

Key Facts about Eastern Marsh Harrier

We have added all key facts about Eastern Marsh Harriers in the table below-

FAQs – UPSC Questions on Eastern Marsh Harrier

Question-1: What is the Eastern Marsh Harrier?

Answer. The Eastern Marsh Harrier (Circus spilonotus) is a bird of prey, belonging to the marsh harrier group, known for its distinctive features and migratory behavior.

Question-2: Where is the Eastern Marsh Harrier usually found?

Answer. Native to eastern Asia, it is commonly sighted in regions like northeast China, Mongolia, and southeast Siberia, with winter migrations extending to southern China, Taiwan, Korea, and Southeast Asia.

Question-3: How does the Eastern Marsh Harrier differ from the Western Marsh Harrier?

Answer. Once considered the same species, they are now classified separately. The Eastern Marsh Harrier has distinct subspecies in eastern Asia, while the Western Marsh Harrier occupies western Eurasia and Africa.

Question-4: What is its conservation status?

Answer. Currently, the Eastern Marsh Harrier holds a “Least Concern” status, indicating a stable population and no immediate threat of extinction.

Question-5: How does the harrier contribute to its ecosystem?

Answer. As an apex predator in wetland habitats, it helps maintain a balance in the ecosystem by controlling populations of small mammals, reptiles, and amphibians.

Question-6: What are the main threats to the Eastern Marsh Harrier?

Answer. The primary threats include habitat loss due to wetland drainage, agricultural intensification, urbanization, pesticide use, and potential impacts of climate change.

Question-7: How does the bird behave during courtship?

Answer. During the breeding season, males engage in elaborate aerial displays involving dives, rolls, and vocal calls to attract females.

Question-8: Where does the Eastern Marsh Harrier build its nest?

Answer. Females construct nests on the ground, typically in dense vegetation like reeds and grasses within their territory.

Question-9: What is the migratory pattern of the Eastern Marsh Harrier?

Answer. It migrates south for the winter, traveling from its breeding grounds in eastern Asia to areas like southern China, Taiwan, Korea, and Southeast Asia.

Question-10: How can birders spot the Eastern Marsh Harrier?

Answer. Spotting the harrier requires experienced birders as it comes to roost during dusk when light is low. Knowledge of its habitat preferences in wetlands, especially during migration periods, is crucial.