Animal migration is the movement of animals, usually on a seasonal basis, between different habitats. It occurs in birds, fish, insects, mammals and other animal groups. Migrations can be seasonal, in response to temperature changes or food availability, or circadian/daily in response to day length. Tracking methods include tags, radio collars, GPS and satellite transmitters to monitor animal movements and routes.

1. MIGRATION OF ANIMALS
NAME: EHTISHAM SHAFIQUE
COLLEGE ROLL NO: 539
University Roll NO: 035975
Subject: Animal Behaviour
Submitted To: Prof. Dr. Amir Sab

2. Contents
1 Overview
1.1 Concepts
1.2 Seasonal
1.3 Circadian
1.4 Tidal
1.5 Diel
2 In specific groups
2.1 In birds
2.2 In fish
2.3 In insects
2.4 In mammals
2.5 In other animals
3 Tracking migration

3.  Animal migration:
Animal migration is the relatively long-distance movement of
individual animals, usually on a seasonal basis. It is the most
common form of migration in ecology. It is found in all major animal
groups, including birds, mammals, fish, reptiles,
amphibians, insects, and crustaceans. The cause of migration may
be local climate, local availability of food, the season of the year or
for mating.
To be counted as a true migration, and not just a local
dispersal or irruption, the movement of the animals should be an
annual or seasonal occurrence, or a major habitat change as part of
their life.
A major habitat change could include young Atlantic
salmon or sea lamprey leaving the river of their birth when they
have reached a few inches in size.

4.  Concepts:
Migration can take very different forms in different species, and has a variety of causes. As such, there is no
simple accepted definition of migration. One of the most commonly used definitions, proposed by the zoologist
J. S. Kennedy is:
Migratory behavior is persistent and straightened-out movement effected by the animal's own locomotory
exertions or by its active embarkation on a vehicle. It depends on some temporary inhibition of station-keeping
responses, but promotes their eventual disinhibition and recurrence.
Migration encompasses four related concepts: persistent straight movement; relocation of an individual on a
greater scale (in both space and time) than its normal daily activities; seasonal to-and-fro movement of a
population between two areas; and movement leading to the redistribution of individuals within a
population. Migration can be either obligate, meaning individuals must migrate, or facultative, meaning
individuals can "choose" to migrate or not. Within a migratory species or even within a single population, often
not all individuals migrate. Complete migration is when all individuals migrate, partial migration is when some
individuals migrate while others do not, and differential migration is when the difference between migratory
and non-migratory individuals is based on discernible characteristics like age or sex.Irregular (non-cyclical)
migrations such as irruptions can occur under pressure of famine, overpopulation of a locality, or some more
obscure influence.

5.  Seasonal
Seasonal migration is the movement of various species
from one habitat to another during the year. Resource
availability changes depending on seasonal
fluctuations, which influence migration patterns. Some
species such as Pacific salmon migrate to reproduce;
every year, they swim upstream to mate and then
return to the ocean. Temperature is a driving factor of
migration that is dependent on the time of year. Many
species, especially birds, migrate to warmer locations
during the winter to escape poor environmental
conditions.

6.  Circadian
Circadian migration is where birds utilise circadian rhythm (CR)
to regulate migration in both fall and spring. In circadian
migration, clocks of both circadian (daily) and circannual
(annual) patterns are used to determine the birds' orientation in
both time and space as they migrate from one destination to the
next. This type of migration is advantageous in birds that,
during the winter, remain close to the equator, and also allows
the monitoring of the auditory and spatial memory of the bird's
brain to remember an optimal site of migration. These birds
also have timing mechanisms that provide them with the
distance to their destination.

7.  Tidal
Tidal migration is the use of tides by organisms to move periodically from one habitat to another.
This type of migration is often used in order to find food or mates. Tides can carry organisms
horizontally and vertically for as little as a few nanometres to even thousands of kilometres. The
most common form of tidal migration is to and from the intertidal zone during daily tidal cycles.
These zones are often populated by many different species and are rich in nutrients. Organisms
like crabs, nematodes, and small fish move in and out of these areas as the tides rise and fall,
typically about every twelve hours. The cycle movements are associated with foraging of marine
and bird species. Typically, during low tide, smaller or younger species will emerge to forage
because they can survive in the shallower water and have less chance of being preyed upon.
During high tide, larger species can be found due to the deeper water and nutrient upwelling
from the tidal movements. Tidal migration is often facilitated by ocean currents.

8.  Diel
While most migratory movements
occur on an annual cycle, some
daily movements are also described
as migration. Many aquatic animals
make a diel vertical migration,
travelling a few hundred metres up
and down the water column,while
some jellyfish make daily horizontal
migrations of a few hundred metres.

9.  In specific groups
Different kinds of animals migrate in different ways.
• In birds:
Approximately 1,800 of the world's 10,000 bird species migrate long distances each
year in response to the seasons. Many of these migrations are north-south, with
species feeding and breeding in high northern latitudes in the summer and moving
some hundreds of kilometer's south for the winter. Some species extend this strategy
to migrate annually between the Northern and Southern Hemispheres. The Arctic
tern has the longest migration journey of any bird: it flies from its Arctic breeding
grounds to the Antarctic and back again each year, a distance of at least 19,000 km
(12,000 mi), giving it two summers every year.
Bird migration is controlled primarily by day length, signalled by hormonal changes in
the bird's body. On migration, birds navigate using multiple senses. Many birds use a
sun compass, requiring them to compensate for the sun's changing position with time
of day. Navigation involves the ability to detect magnetic fields.

10. • In fish
Most fish species are relatively limited in their movements, remaining in a single
geographical area and making short migrations to overwinter, to spawn, or to feed.
A few hundred species migrate long distances, in some cases of thousands of
kilometres. About 120 species of fish, including several species of salmon, migrate
between saltwater and freshwater (they are 'diadromous').
Forage fish such as herring and capelin migrate around substantial parts of the
North Atlantic ocean. The capelin, for example, spawn around the southern and
western coasts of Iceland; their larvae drift clockwise around Iceland, while the fish
swim northwards towards Jan Mayen island to feed and return to Iceland parallel
with Greenland's east coast.
In the 'sardine run', billions of Southern African pilchard Sardinops sagax spawn in
the cold waters of the Agulhas Bank and move northward along the east coast
of South Africa between May and July.

11. • In insects:
Some winged insects such as locusts and certain butterflies and dragonflies with
strong flight migrate long distances. Among the dragonflies, species
of Libellula and Sympetrum are known for mass migration, while Pantala flavescens,
known as the globe skimmer or wandering glider dragonfly, makes the longest
ocean crossing of any insect: between India and Africa. Exceptionally, swarms of the
desert locust, Schistocerca gregaria, flew westwards across the Atlantic Ocean for
4,500 kilometres (2,800 mi) during October 1988, using air currents in the Inter-
Tropical Convergence Zone.[27]
In some migratory butterflies, such as the monarch butterfly and the painted lady, no
individual completes the whole migration. Instead, the butterflies mate and
reproduce on the journey, and successive generations continue the migration.

12. • In mammals:
• Some mammals undertake exceptional migrations; reindeer have one of the
longest terrestrial migrations on the planet, reaching as much as 4,868
kilometres (3,025 mi) per year in North America. However, over the course of a
year, grey wolves move the most. One grey wolf covered a total cumulative
annual distance of 7,247 kilometres (4,503 mi).
• Humans are mammals, but human migration, as commonly defined, is when
individuals often permanently change where they live, which does not fit the
patterns described here. An exception is some traditional migratory patterns
such as transhumance, in which herders and their animals move seasonally
between mountains and valleys, and the seasonal movements of nomads.

13. • In other animals
• Among the reptiles, adult sea turtles migrate long distances to breed, as do
some amphibians. Hatchling sea turtles, too, emerge from underground nests,
crawl down to the water, and swim offshore to reach the open sea.
Juvenile green sea turtles make use of Earth's magnetic field to navigate.
• Some crustaceans migrate, such as the largely-terrestrial Christmas Island red
crab, which moves en masse each year by the millions. Like other crabs, they
breathe using gills, which must remain wet, so they avoid direct sunlight, digging
burrows to shelter from the sun. They mate on land near their burrows. The
females incubate their eggs in their abdominal brood pouches for two weeks.
They then return to the sea to release their eggs at high tide in the moon's last
quarter. The larvae spend a few weeks at sea and then return to land.

14.  Tracking migration
Scientists gather observations of animal migration by tracking their movements.
Animals were traditionally tracked with identification tags such as bird rings for later
recovery. However, no information was obtained about the actual route followed
between release and recovery, and only a fraction of tagged individuals were
recovered. More convenient, therefore, are electronic devices such as radio-tracking
collars that can be followed by radio, whether handheld, in a vehicle or aircraft, or by
satellite. GPS animal tracking enables accurate positions to be broadcast at regular
intervals, but the devices are inevitably heavier and more expensive than those
without GPS. An alternative is the Argos Doppler tag, also called a 'Platform
Transmitter Terminal' (PTT), which sends regularly to the polar-orbiting Argos
satellites; using Doppler shift, the animal's location can be estimated, relatively
roughly compared to GPS, but at a lower cost and weight. A technology suitable for
small birds which cannot carry the heavier devices is the geolocator which logs the
light level as the bird flies, for analysis on recapture. There is scope for further
development of systems able to track small animals globally.

15. THANKS