Abstract
By computers imulationso f differentf lightr outesf or springm igratingK nots Calidris
canutusp, otentialo rientationa'ld angerz ones' werer evealedi n the equatora rea and
northo f the Arcticc ircle.A n evaluationo f the availabilityo f directionailn formation
duringm igratoryf lightsd emonstratedth e potentialh azardso f crossingt hese danger
zones. Investigationso f the directionalc onsequenceso f sun compass orientation
based upon an internalc lock in phase with local time at the departures ite showed
that such a mechanism would entail serious losses in distance and time. A simple
compensatingr uleb asedo n the rateo f changei n sun altitudew as foundt o workw ell
both at polar latitudes and in the equator area. The magnetic compass will become
inoperativec lose to the magnetice quatora nd the poles, thus restrictingth e availability
of directional information. Orientation by stellar cues will become impossible
during spring and summer at arctic latitudes. Simulations of potential migratory
routesa lso enablede xaminationo f the requiredp recisiono f compasss ystemsa nd it
was indicatedt hat necessaryo rientationa ccuracyr equiresm ore than one directional
selectionp er long-distancef light to ensure survival.I t is concludedt hat computer
simulations of flight tracks, based on ringing recoveries, visual observations, radar
studies and satellite telemetry may be a powerful tool helping to identify problems
which require future experimental attention.
canutusp, otentialo rientationa'ld angerz ones' werer evealedi n the equatora rea and
northo f the Arcticc ircle.A n evaluationo f the availabilityo f directionailn formation
duringm igratoryf lightsd emonstratedth e potentialh azardso f crossingt hese danger
zones. Investigationso f the directionalc onsequenceso f sun compass orientation
based upon an internalc lock in phase with local time at the departures ite showed
that such a mechanism would entail serious losses in distance and time. A simple
compensatingr uleb asedo n the rateo f changei n sun altitudew as foundt o workw ell
both at polar latitudes and in the equator area. The magnetic compass will become
inoperativec lose to the magnetice quatora nd the poles, thus restrictingth e availability
of directional information. Orientation by stellar cues will become impossible
during spring and summer at arctic latitudes. Simulations of potential migratory
routesa lso enablede xaminationo f the requiredp recisiono f compasss ystemsa nd it
was indicatedt hat necessaryo rientationa ccuracyr equiresm ore than one directional
selectionp er long-distancef light to ensure survival.I t is concludedt hat computer
simulations of flight tracks, based on ringing recoveries, visual observations, radar
studies and satellite telemetry may be a powerful tool helping to identify problems
which require future experimental attention.
Original language | English |
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Pages (from-to) | 626-636 |
Journal | Journal of Avian Biology |
Volume | 29 |
Issue number | 4 |
Publication status | Published - 1998 |
Bibliographical note
The information about affiliations in this record was updated in December 2015.The record was previously connected to the following departments: Animal Ecology (Closed 2011) (011012001), Department of Statistics (012014000)
Subject classification (UKÄ)
- Ecology
- Probability Theory and Statistics