What is Bird’s Migration?
- Definition: Bird migration is the regular seasonal movement, often north and south, along a flyway between breeding and wintering grounds. It involves the movement of many bird species.
- Factors Influencing Migration: Migration is primarily influenced by the availability of food. Birds migrate to areas where food resources are abundant. However, migration comes with significant costs, including predation and mortality, especially from human hunting.
- Geographic Patterns: Migration is more common in the northern hemisphere, where natural barriers like the Mediterranean Sea or the Caribbean Sea direct birds along specific paths or flyways.
- Historical Records: The migration of animals, including storks, turtledoves, and swallows, was noted by Ancient Greek authors such as Homer and Aristotle over 3,000 years ago. Early records of spring migrant arrivals were also kept by Johannes Leche in Finland in 1749.
- Migration Challenges: Threats to migratory birds have increased due to habitat destruction, including loss of stopover and wintering sites, as well as human-made structures such as power lines and wind farms.
- Long-Distance Migration: Some bird species hold impressive migration records. The Arctic tern, for example, travels between Arctic breeding grounds and the Antarctic each year. Certain tubenose species, like albatrosses, circle the Earth over the southern oceans.
- Migration Timing and Navigation: The timing of migration is primarily controlled by changes in day length. Birds navigate using celestial cues from the sun and stars, the Earth’s magnetic field, and mental maps.
- Etymology: The word “migration” is derived from the Latin word “migrare,” meaning movement from one spatial unit to another. In the case of birds, migration refers to the annual journey between specific breeding and non-breeding places to take advantage of favorable conditions.
- Two-Way Journey: Bird migration involves a two-way journey. Birds travel from their breeding and nesting places (called home) to feeding and resting places (called new places) and then make the return journey back home. They follow the same route during migration.
- Seasonal Movement: Bird migration occurs during specific periods of the year, typically following a seasonal pattern. The purpose is to benefit from favorable conditions at different locations throughout the year.
Why do Birds Migrate? – Reason for migration in birds
- Resource Availability: Birds migrate to move from areas with low resources to areas with high resources, or vice versa. The two main commodities sought after are food and nesting places.
- Breeding Opportunities: Birds that breed in the Northern Hemisphere migrate northward in the spring. They do this to take advantage of the abundance of nesting sites, expanding insect populations, and blossoming plants.
- Seasonal Changes: Birds migrate south as winter approaches because the number of insects and other food sources decreases. They seek more favorable conditions in regions where food is still available.
- Escape from Cold: Escape from cold temperatures is a driving force behind migration. However, certain species, such as hummingbirds, can tolerate subfreezing temperatures if they have access to sufficient food.
Factors Influencing Migration Stimulus:
- Environmental Stimulus: Changes in temperature and food availability are believed to trigger migration. Decreased daylight hours during autumn in temperate and Northern Hemisphere regions reduce the time available for food gathering, initiating autumnal migration. Similarly, increasing day length and elevated temperatures in the Southern Hemisphere during spring act as initiators of migration.
- Physiological Stimulus: Scientists are studying the role of endocrine glands, including the pituitary, gonad, thyroid, adrenal, and pineal glands, in migration. These glands regulate various metabolic processes and may play a role in initiating migratory behaviors. Hormones such as thyroid hormones and gonadal hormones are believed to influence the deposition of fat, an important aspect of migration in many bird species.
What are Migratory Species?
Migratory species are defined as wild animals, including birds and mammals, whose populations or specific geographic portions of their populations regularly and predictably cross national jurisdictional lines. Here are some key points about migratory species:
- Movement across boundaries: Migratory species are characterized by their regular movement across one or more national borders. They undertake these journeys as part of their natural life cycle, often traveling long distances between different habitats.
- Extensive travel: Some migratory birds and mammals cover vast distances during their migrations, spanning thousands of miles or kilometers. These remarkable journeys involve navigating across various landscapes and habitats.
- Nesting and habitat requirements: Migratory paths often encompass the need for nesting or breeding grounds, as well as suitable habitats before and after each movement. These species rely on specific environments to fulfill their reproductive and survival needs.
- Vulnerability to threats: Migratory species face various challenges that can impact their populations. Habitat loss and degradation in breeding sites, increased hunting along migration routes, and degradation of their feeding grounds are among the concerns that make migratory animals particularly vulnerable.
- International conservation efforts: In response to the global concern over the threats faced by migratory species, governments ratified the 1979 Convention on the Conservation of Migratory Species (CMS) of Wild Animals. The CMS aims to promote international cooperation for the conservation and sustainable use of migratory species and their habitats.
The conservation of migratory species is crucial for maintaining biodiversity, as they play vital roles in ecosystems and connect different habitats and regions. Protecting their habitats, ensuring safe migration routes, and minimizing human-induced threats are essential for the survival and well-being of these remarkable animals.
Features of Bird’s Migration
Bird migration exhibits several distinctive features that enable birds to undertake their long-distance journeys. Here are some key characteristics of bird migration:
- Morphological and physiological adaptations: Migratory birds possess specific morphological features and physiological adaptations that facilitate their migration. These adaptations may include efficient flight mechanisms, streamlined body shapes, and specialized respiratory and cardiovascular systems that support endurance during long flights.
- Migration strategy and timing: Migratory birds have the ability to switch between sedentary and migratory lifestyles based on environmental cues. They can assess the optimal timing and route for their migration, taking advantage of favorable conditions such as weather patterns, food availability, and breeding opportunities.
- Energy reserves: During periods of rest between migrations, migratory birds tend to accumulate energy reserves in the form of lipids or fat deposits. These reserves serve as fuel for their long-distance flights, providing them with the necessary energy to sustain their journeys.
- Environmental triggers: The initiation of migration is influenced by environmental factors, with changes in day length playing a significant role. Birds possess genetic and physiological mechanisms that respond to these environmental cues and trigger the onset of migration.
- Scientific understanding: The study of migratory birds has provided scientific insights into the mechanisms and processes involved in migration. Numerous researchers have documented the physiological, genetic, and behavioral aspects specific to migratory birds, enhancing our understanding of their remarkable abilities.
- Flight capabilities: Migratory birds exhibit a wide range of flight capabilities. Some species fly at low altitudes within the range of human vision, while others soar at high altitudes. For example, songbirds typically fly at heights of 500 to 2000 feet, whereas larger birds like geese or vultures have been known to fly at altitudes of 29,000 to 37,000 feet.
Bird migration is a complex phenomenon that showcases the remarkable adaptability and navigational abilities of avian species. Understanding the features of bird migration helps us appreciate the incredible journeys undertaken by these birds and highlights the need for conservation efforts to protect their habitats and ensure the sustainability of their migrations.
Adaptation of Bird’s Migration
Bird migration is accompanied by various adaptations that enable birds to meet the demands of their long-distance journeys. Here are some key adaptations observed in migratory birds:
- Metabolic changes: Migration requires birds to make significant metabolic adjustments. To fuel their flights, birds undergo metabolic shifts that involve increased fat deposition. This allows them to store and utilize energy-rich fats as a source of fuel during their journey.
- Sleep regulation: Nocturnal migrants face the challenge of navigating and flying during the night. These birds have specific adaptations to regulate sleep patterns and ensure optimal rest while on the move. They have the ability to sleep with one hemisphere of the brain at a time, known as unihemispheric sleep, allowing them to maintain vigilance while still obtaining necessary rest.
- Feather molt: Feathers play a crucial role in flight, and their condition is vital for migratory birds. Birds molt their feathers to replace worn-out or damaged ones. The timing of molt varies among species, with some birds molting before migration, ensuring they have a fresh set of feathers for their journey.
- Behavioral adaptations: Migration often involves behavioral modifications to enhance the efficiency and safety of the journey. Flocking behavior is commonly observed, as birds fly in groups to reduce energy expenditure and minimize the risk of predation. Flocking also provides social benefits, such as increased communication and navigation cues from fellow group members.
- Navigation abilities: Migratory birds possess remarkable navigational skills that allow them to find their way over vast distances. They rely on a combination of celestial cues, such as the position of the sun and stars, magnetic fields, landmarks, and even visual or olfactory cues for specific routes. These navigational adaptations enable birds to accurately navigate along their migratory paths.
The adaptations exhibited by migratory birds reflect their remarkable ability to adjust their physiology, behavior, and navigation strategies to meet the challenges of long-distance journeys. Understanding these adaptations helps us appreciate the incredible resilience and survival mechanisms of migratory bird species and underscores the importance of conserving their habitats and migration routes.
Types of Migration in Bird
Migration is broadly divided into the following three kinds:
- Return Migration: This refers to the migration of birds to a previously known place that has been visited earlier. Birds migrate back to the same location where they have previously bred or spent a significant part of their life cycle.
- Exploratory Migration: Exploratory migration involves birds moving to a completely unknown space that they have not visited before. In this type of migration, the birds may retain the ability to return to their original location, but they do not exploit it. Instead, they venture into new territories to explore and potentially find new resources or breeding sites.
- Removal Migration: Removal migration occurs when birds migrate to a comparable spatial unit but do not return to their original location. They move to a different area that is similar in terms of resources or environmental conditions. This type of migration may be triggered by factors such as competition for resources or changes in habitat availability.
It’s important to note that these categories provide a general framework for understanding bird migration patterns, and individual bird species may exhibit variations or combinations of these migration types based on their specific ecological requirements and behaviors.
Based upon the plane of movement of the migrants
Based upon the plane of movement of the migrants, bird migration can be categorized as follows:
- Horizontal Migration:
- Latitudinal Migration:
- Migration occurring from north to south or vice versa is called latitudinal migration.
- It is more commonly observed from north to south, but some species migrate in the opposite direction.
- Examples include the cuckoo, which breeds in India and spends the summer in Southeast Africa, covering a distance of about 7250 km.
- The ruff breeds in Siberia and travels to Great Britain, Africa, India, and Sri Lanka, covering a distance of about 9650 km.
- Longitudinal Migration:
- Longitudinal migration takes place in the east-west direction.
- Some birds move from inland areas towards the Atlantic coast to avoid the continental winter.
- The pentagonian plover visits the Falkland Islands and South Patagonia in September and October for breeding.
- Latitudinal Migration:
- Vertical Migration:
- Migration occurring in a plane parallel to the gravitational pull of the earth is called vertical migration.
- Altitudinal Migration:
- Altitudinal migration involves both horizontal and vertical components.
- Birds fly up and down over mountains and hills.
- Migration usually occurs at relatively low altitudes, with small passerine birds flying at a height of around 60 meters.
- Some birds have been observed flying at altitudes of up to 4000 meters.
- In India, many birds migrate from the plains to the slopes of the Himalayas, ascending thousands of feet above sea level during the summer and returning to the plains when winter arrives.
- These movements are classified as altitudinal migration.
It’s important to note that birds can exhibit combinations of these migration types, and the specific patterns may vary among different species based on their ecological needs and environmental factors.
Based on time of flight which occurs during migration
Based on the time of flight during migration, birds can be classified into the following categories:
- Diurnal Migration:
- Many large birds undertake migration flights during the day.
- Examples of diurnal migratory birds include crows, swallows, robins, hawks, cranes, and pelicans.
- Some diurnal migratory birds may make stops along their journey to forage in suitable places.
- Swallows and swifts are capable of capturing their insect food in the air while in flight.
- Diurnal migratory birds often travel in flocks, which can be well-organized.
- Nocturnal Migration:
- The majority of small-sized birds, such as sparrows, warblers, and thrushes, prefer to migrate at night.
- They take advantage of the darkness for protection from predators.
- Nocturnal migratory birds feed and rest during the day.
- However, some birds, like geese and ducks, exhibit both diurnal and nocturnal flight during migration. They may fly continuously, day and night, to reach their destination.
It’s important to note that while these categories generally describe the timing of migration flights, there can be variations among different bird species and individual behavior. Migration patterns are influenced by a combination of factors, including species-specific characteristics, environmental conditions, and evolutionary adaptations.
Based on reasons of migration
Based on the reasons for migration, birds can be categorized as follows:
- Climatic Migration:
- Birds undertake climatic migration in response to changes in environmental conditions, particularly climate.
- An example of climatic migration is the north-south migration of many ducks and geese.
- These birds move from their breeding grounds in the north to warmer regions in the south during winter to avoid harsh winter conditions.
- Alimental Migration:
- Alimental migration occurs when birds migrate in search of food resources.
- This type of migration can happen at any time of the year when there is a scarcity of food in their current habitat.
- Birds may travel long distances to find areas with abundant food sources, such as insects, fruits, or nectar.
- Gamatic Migration:
- Gamatic migration is driven by the need for a specific environment to successfully complete certain aspects of the reproductive process.
- Many bird species exhibit gamatic migration, where they migrate to specific breeding grounds or nesting sites to find suitable mates and create optimal conditions for breeding.
- These migrations are often characterized by elaborate courtship displays and the establishment of territories.
It’s important to note that these categories are not mutually exclusive, and a bird’s migration can be influenced by multiple factors simultaneously. Migration patterns can vary among species, and individual birds within a species may exhibit different migration behaviors based on factors like age, sex, and individual experiences.
Based on seasons during which birds migrate
Based on the seasons during which birds migrate, they can be classified as follows:
- Summer Visitors:
- These birds arrive in the spring from the south and migrate to breed in areas with more favorable conditions.
- They leave for the south during autumn when the breeding season is over.
- Examples of summer visitors include Swifts, Swallows, Nightingales, Cuckoos, and other migratory species that come to breed in the northern regions.
- Winter Visitors:
- Winter visitors are birds that migrate southward and southwest during the winter months to escape the harsh conditions of their breeding grounds.
- They return to the north in spring when the weather becomes more suitable for breeding.
- Birds such as Fieldfares, Snow Buntings, Redwings, and other wintering species exhibit this pattern of migration.
- Birds of Passage:
- Birds of passage are species that are observed for a short period twice a year as they travel to and from colder or warmer regions.
- They pass through certain areas during spring and autumn on their way to their final breeding or wintering grounds.
- Examples of birds of passage include Sandpipers, Sparrows, and other migratory species that use specific stopover sites during their journey.
It’s important to note that the timing and duration of these migrations can vary depending on the specific species and their geographic location. Some birds may have more complex migration patterns, with multiple stopovers along their migratory routes.
Guiding Mechanisms in Bird Navigation
- Fat deposition:
- Migratory birds accumulate fat in the subcutaneous region of their bodies.
- Fat reserves provide energy for the long-distance migration.
- Fat deposition enables birds to follow a specific route and reach their destination.
- Restlessness, known as zugunruhe, is observed among birds after fat deposition, signaling their readiness for migration.
- Inherited instinct:
- Birds involved in migration possess an inherited instinct.
- The direction and goal of their journey are encoded in their genetic makeup.
- This instinct allows bird populations to adapt to specific locations or environments.
- Experienced lead the flock:
- Older and experienced birds may lead the way and guide the younger generation.
- Applicable to certain flock-flying birds like swans, geese, and cranes.
- Not applicable to all species, as some exhibit different migration timings between adults and juveniles.
- Remarkable experiments:
- Werner Ruppell discovered that Starlings could find their way back to their nests from distances of about 2000 km.
- A Manx shearwater, flown from the western coast of England to Boston, returned to its nest within 12 days, covering 4940 km across the Atlantic Ocean.
- The golden plover of North America migrates from the Hawaiian islands to northern Canada, flying for several weeks over thousands of kilometers of ocean.
- Birds’ navigation abilities:
- Birds possess incredible power of navigation and orientation.
- They can find their destination even under challenging conditions.
- Examples include migrating without webbed feet or traversing unfamiliar territories.
Note: While many theories exist on bird migration, these mechanisms provide insights into how birds navigate during their migratory journeys.
Various theorists propose that birds are guided by a number of agencies:
a. Earth’s magnetic field as the guiding factor:
- Ornithologists suggest the existence of a “magnetic sense” in birds for geographical orientation.
- Yeagley conducted experiments in 1947 and 1951, proposing that birds are guided by the earth’s magnetic field.
- However, attempts to demonstrate this experimentally have not supported Yeagley’s theory.
b. Sun as the guiding agent in diurnal migration:
- Gustav Kramer and G. V. T. Matthews proposed that birds use the position of the sun as a compass during migration.
- Homing pigeons and many wild birds possess a “time sense” or “internal clock” to track the sun’s motion across the sky.
- Kramer’s experiments on Starlings showed that they use the sun to set their migratory course.
- Clear skies allow Starlings to maintain the correct direction, while overcast skies cause confusion.
c. Stars as the guiding agent in nocturnal migration:
- Birds like warblers navigate primarily at night and use stars for orientation.
- E.G.F. Sauer conducted experiments with white throat warblers in a planetarium.
- Warblers failed to orient themselves when stars were not visible, but followed the proper direction when the planetarium sky matched the natural night sky.
- Sauer suggested that warblers possess an inherited mechanism to navigate by the stars during nocturnal migration.
d. The “compass” and the “internal clock” in bird migration:
- Birds have a built-in compass that helps them navigate during migration.
- The position of the sun plays a vital role in controlling the navigation pathways.
- Birds have an inherent ability to make appropriate allowances for the time of day.
- Birds possibly have an internal clock that synchronizes with the earth’s rotation and external cues.
Telemetry and tracking methods:
- Telemetry involves tracking bird movement using radio signals.
- Miniature radio transmitters attached to birds allow researchers to track their migration routes.
- This method helps in understanding the migratory patterns of birds.
- More recently, satellite and radar tracking instruments have been used to track migratory bird routes.
Note: These theories and tracking methods provide valuable insights into the guiding mechanisms that birds employ during migration.
Migratory Birds of India
India is home to a diverse range of migratory birds, with the Indian subcontinent serving as an important stopover and wintering ground for many species. Here are some key points about migratory birds in India:
- Number of migratory species: Out of the approximately 2000 bird species and subspecies found in India and South Asia, around 350 are migratory species. This demonstrates the significant presence of migratory birds in the region.
- Winter migrants: The majority of migratory birds in India are winter migrants. These birds travel to India from their breeding grounds in search of favorable feeding and breeding conditions or to escape the harsh winters in their native habitats.
- Range of migratory species: Over 100 different kinds of migratory birds visit India, highlighting the rich diversity of species that undertake long-distance journeys to the region. These birds belong to various families and include species such as Amur falcons, Bar-headed geese, and Black-necked cranes, which are notable migratory species found in India.
- Central Asian Flyway (CAF): India is a part of the Central Asian Flyway, a major migratory bird route that extends from the Arctic to the Indian Ocean. This flyway encompasses several countries and provides critical stopover sites for migratory birds during their journeys.
- Conservation efforts: Recognizing the importance of migratory birds and their habitats, India is a signatory to the Convention on Migratory Species (CMS). As part of its commitment to conservation, India has developed the National Action Plan for the Conservation of Migratory Species in the Central Asian Flyway. This plan aims to protect and conserve critical habitats, address threats to migratory species, and promote international cooperation for their conservation.
The presence of migratory birds in India not only adds to the country’s rich biodiversity but also highlights the need for conservation efforts to safeguard their habitats and migration routes. These birds serve as important indicators of ecological health and contribute to the overall ecosystem functioning. Protecting and preserving their habitats is crucial for the long-term survival of migratory bird species in India.
Migratory Birds of India – Threats
Migratory birds in India face various threats throughout their migration journey. Here are some key threats that impact these birds:
- Loss of biodiversity: Migratory birds are affected by the loss of biodiversity, which is caused by factors such as overexploitation, unsustainable use of natural resources, population growth, weather variability, and climate change. These factors lead to habitat degradation and fragmentation, reducing the availability of suitable habitats for migratory birds.
- Illegal killing: Hunting and illegal trapping of migratory bird species along their migration pathways pose a significant threat to their populations. These activities are driven by the demand for bird products, such as feathers and body parts, and can result in the decline of migratory bird populations.
- Stopover habitat loss: Migratory birds rely on stopover sites during their journey to rest, refuel, and replenish their energy reserves. However, the loss and degradation of these crucial habitats due to factors like overexploitation, land conversion, and urbanization have reduced the availability of suitable stopover sites for migratory birds.
- Collision with structures: Migratory birds are at risk of colliding with human-made structures such as power lines, wind turbines, communication towers, and offshore oil rigs. These collisions can cause injury or death to the birds, especially during adverse weather conditions or in areas with poor visibility.
- Pesticide poisoning: Migratory birds are vulnerable to pesticide poisoning when they come into contact with agricultural chemicals. Pesticides used in farming can directly harm migratory birds, leading to mortality or negatively affecting their reproductive success.
- Increasing illumination: Artificial nighttime lighting, particularly in urban areas, can disrupt the migratory patterns of birds. It can confuse their navigation systems and lead to disorientation, causing them to stray off their intended migration routes or become more susceptible to predation.
- Increasing encroachment: Human activities, such as urban expansion, agriculture, and infrastructure development, encroach upon natural habitats used by migratory birds. This encroachment reduces the availability of food sources and disrupts the birds’ foraging and nesting areas, leading to food scarcity and potential starvation.
Addressing these threats requires a combination of conservation efforts, including habitat preservation, enforcement of wildlife protection laws, raising awareness about the importance of migratory birds, promoting sustainable land use practices, and reducing the use of harmful pesticides. International collaboration and cooperation are also crucial for the conservation of migratory birds, as their journeys often span multiple countries and jurisdictions. By mitigating these threats, we can help ensure the survival and well-being of migratory birds in India.
Migratory Birds of India – Steps to be Taken
To ensure the conservation and well-being of migratory birds in India, the following steps can be taken:
- Long-term monitoring studies: Conducting ongoing monitoring studies to track bird movement patterns, assess population counts, and monitor the prevalence of diseases among migratory birds. This data can provide valuable insights into their behavior and help guide conservation efforts.
- Spreading knowledge and community support: Raise awareness about bird migration and its ecological importance among local communities, schools, and the general public. Encourage community participation in bird nesting and conservation initiatives, promoting a sense of responsibility and ownership.
- Regulating fishing operations: Implement measures to reduce, abandon, or prohibit fishing activities during the migration season in areas where birds congregate. This helps minimize disturbance to the birds and protects their feeding and resting habitats.
- Maintaining natural habitats: Preserve and restore natural habitats that are essential for migratory birds, including wetlands, forests, and grasslands. Create bird-friendly landscaping in urban areas to provide suitable habitats for roosting and nesting.
- Plastic waste management: Prohibit the use of single-use plastics and establish effective waste management systems to prevent plastic pollution in water sources. Migratory birds can mistake plastic debris for food, leading to ingestion and other harmful consequences.
- Law enforcement: Enforce strict wildlife protection laws and regulations to deter illegal activities such as hunting, trapping, and trade of migratory birds. Ensure the penalties for these offenses are sufficient to deter potential violators.
- Utilizing modern technologies: Explore the use of modern technologies like drones to monitor and detect poaching activities along migration routes. This can help authorities take timely action against illegal activities and protect migratory birds.
- Reducing nighttime lighting: Minimize artificial nighttime lighting along migration routes, especially in areas where birds may become disoriented. This can be achieved through the use of shielded lights, turning off unnecessary lighting, and raising awareness about the negative impacts of excessive illumination.
- Public awareness and education: Increase public awareness about the importance of maintaining natural habitats for migratory birds and the need for their conservation. Conduct educational campaigns, workshops, and nature tours to engage people in bird conservation efforts.
By implementing these steps, India can contribute to the conservation of migratory birds, protect their habitats, and ensure their safe passage during their annual migrations. Collaboration between government agencies, conservation organizations, local communities, and the public is crucial to the success of these efforts.
Convention On The Conservation Of Migratory Species (CMS)
- The Convention on the Conservation of Migratory Species of Wild Animals (CMS), also known as the Bonn Convention, is an international treaty established under the United Nations Environment Programme (UNEP). The primary objective of the convention is to promote the conservation and sustainable use of migratory species and their habitats worldwide.
- The CMS recognizes that migratory species, including birds, mammals, fish, and even some insects, traverse multiple countries during their annual migrations. These species face numerous threats such as habitat loss, pollution, climate change, and unsustainable hunting along their migration routes. The CMS aims to address these challenges by fostering international cooperation and coordination among nations.
- One of the key features of the CMS is its focus on the conservation of wildlife and ecosystems at a global level. It recognizes the importance of conserving migratory species not only within individual countries but also throughout their entire migratory range. This approach emphasizes the need for collaborative efforts between countries to ensure the long-term survival of migratory species.
- The CMS provides a platform for countries to come together and develop conservation strategies, action plans, and guidelines for the protection of migratory species. Currently, 173 migratory species from around the world are listed under the convention for special protection. These species include iconic animals like whales, dolphins, elephants, turtles, birds of prey, and many others.
- The CMS operates through a Conference of the Parties (COP) that meets every three years to review progress, make policy decisions, and establish conservation priorities. The COP brings together governments, non-governmental organizations, scientists, and other stakeholders to exchange information, share best practices, and collaborate on initiatives to protect migratory species.
- It is worth noting that the CMS is the only international convention that specifically addresses the conservation and management of migratory species. By ratifying the Bonn Convention, countries commit to implementing measures to protect and conserve migratory species within their respective territories.
- The Central African Republic is among the countries that have recognized the importance of conserving migratory species and ratified the CMS on September 1, 2020. This highlights the growing global recognition and commitment to addressing the conservation challenges faced by migratory species.
- In conclusion, the Convention on the Conservation of Migratory Species plays a vital role in promoting international cooperation and collective action for the conservation of migratory species worldwide. By bringing countries together and facilitating the exchange of knowledge and expertise, the CMS strives to ensure the long-term survival and well-being of these remarkable animals.
Disadvantages of Bird Migration
i. High mortality rate among young birds:
- Many young birds are unable to reach their destination as they perish during the long and arduous journey.
- The physical demands and challenges of migration can be overwhelming for inexperienced birds.
ii. Adverse weather conditions:
- Sudden changes in climate, such as storms, hurricanes, strong winds, and fog, pose significant risks to migrating birds.
- These weather conditions can disorient birds, cause exhaustion, and increase the likelihood of mortality.
iii. Man-made structures and hazards:
- Tall towers and lighthouses can be fatal obstacles for migratory birds, leading to collisions and fatalities.
- Birds may become disoriented by artificial lights, leading them off course or into dangerous areas.
iv. Human activities and hunting:
- Humans are sometimes responsible for the death of migratory birds.
- Birds are shot at for recreational purposes, depriving them of their chance to complete their migration and survive.
Note: While bird migration is a remarkable phenomenon, it comes with its share of disadvantages and risks for the birds involved. Protecting and conserving migratory bird habitats and raising awareness about the importance of their survival are crucial to minimize these disadvantages.
FAQ
What is bird migration?
Bird migration refers to the seasonal movement of birds from one geographic location to another, usually driven by changes in food availability, breeding opportunities, or climate conditions.
Why do birds migrate?
Birds migrate to find better breeding grounds, access abundant food sources, or escape unfavorable weather conditions in their current location.
How do birds know when to migrate?
Birds have internal biological clocks and are sensitive to changes in daylight length and other environmental cues. These cues help them determine the appropriate time to start their migration.
How far do birds migrate?
The distance birds migrate varies greatly depending on the species. Some birds migrate short distances, such as a few hundred kilometers, while others undertake journeys of thousands of kilometers.
Do all birds migrate?
No, not all birds migrate. Some bird species are resident birds and remain in their breeding or non-breeding territories year-round.
How do birds navigate during migration?
Birds use a combination of celestial cues, landmarks, magnetic fields, and their innate sense of direction to navigate during migration. They also rely on visual and auditory cues to stay on course.
Can birds get lost during migration?
While birds have remarkable navigational abilities, they can sometimes get disoriented or lost due to adverse weather conditions, human-made structures, or other factors that interfere with their normal navigation cues.
How long does migration take for birds?
The duration of migration varies depending on the distance to be covered and the bird species. Some birds complete their migration in a matter of days, while others may take weeks or even months.
Can birds die during migration?
Yes, migration is a perilous journey, and birds face various risks along the way. These risks include exhaustion, predation, adverse weather conditions, and collisions with human-made structures, all of which can result in mortality.
Are there conservation efforts to protect migratory birds?
Yes, there are numerous conservation efforts aimed at protecting migratory birds and their habitats. These include establishing protected areas, promoting awareness and education, reducing threats such as habitat loss and pollution, and implementing international agreements for bird conservation, such as the Migratory Bird Treaty Act.
References
- https://bncollegebgp.ac.in/wp-content/uploads/2020/04/BSc-Zoology-Part-III-Migration-in-Birds.pdf
- https://www.allaboutbirds.org/news/the-basics-how-why-and-where-of-bird-migration/#
- https://www.biologydiscussion.com/zoology/birds/bird-migration-definition-types-causes-and-guiding-mechanisms/41286
- https://pcsstudies.com/migration-in-birds-adaptation-reason-and-types-of-migration/
- https://prepp.in/news/e-492-birds-migration-environment-notes
- https://www.notesonzoology.com/birds/migration-of-birds-kinds-and-modes-vertebrates-chordata-zoology/8280