Random article ( of 1069 ) Latest updates

User Tools

Site Tools


Wikenigma - an Encyclopedia of Unknowns Wikenigma - an Encyclopedia of the Unknown

Bird Migration

Around 50% of birds migrate (i.e. undertake large-scale routine long distance travel for breeding / feeding).

The distances covered can be huge - e.g. Manx Shearwaters migrate 14,000 km (8,700 mi) each year. The time-triggers, and the methods of route navigation, have been widely investigated, but much of the detail is still unknown.

See: Wikipedia

It is known that birds use a variety of methods - magnetic fields, star positions, odours etc, and some species are 'taught' navigation routes by their parents and peers. But others, e.g. the Marsh Warlbler are hatched with built-in mental 'maps' - and an acute 'diary' (i.e. timing) system. How these systems operate, and the way that this information is somehow encoded into their genes is entirely unknown.

A BBC audio discussion on the phenomenon can be found here : In Our Time, June 2020

Also see : Pigeon navigationplugin-autotooltip__plain plugin-autotooltip_bigPigeon navigation

Homing pigeons can very reliably find their way back to their adopted roosting place - even when they have been physically removed hundreds of kilometres away - and often without any knowledge of the removal route.

It's known that they use a variety of methods to navigate - including
and Marine Turtle Migrationplugin-autotooltip__plain plugin-autotooltip_bigMarine Turtle Migration

Several species of marine turtle accurately migrate thousands of kilometers for nesting. Some species return to the exact beach where they were hatched. There are various proposed explanations for the behaviour, including magnetic navigation. But an experiment by
and Monarch Butterfly migrationplugin-autotooltip__plain plugin-autotooltip_bigMonarch Butterfly migration

"Monarch butterfly migration is the phenomenon, mainly across North America, where the subspecies Danaus plexippus plexippus migrates each summer and autumn to and from overwintering sites on the West Coast of California or mountainous sites in Central Mexico.
and The Sardine Runplugin-autotooltip__plain plugin-autotooltip_bigThe Sardine Run

"The term ‘sardine run’ is part of the cultural heritage of the South African nation and refers to a natural phenomenon that is well known to the general public but still poorly understood from an ecological perspective. This lack of understanding has stimulated numerous hypotheses, often contradictory, that try to explain why (ultimate factors) and how (proximate factors) the run occurs.

Show another (random) article

Suggestions for corrections and ideas for articles are welcomed : Get in touch!

Further resources :