Age-Dependent Orientation to Magnetically-Simulated Geographic Displacements in Migratory Australian Silvereyes (Zosterops l. lateralis)

Deutschlander, Mark E.; Phillips, John B.; Munro, Ursula

doi:10.1676/11-043.1

Cited by 30 publications

(29 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The electrophysiological study by Semm and Beason (1990) pointed towards magnetic intensity, and the observations of Munro et al (1997) that young Australian Silvereyes remain unaffected by the pulse also speaks in favor of a learned system, which suggests the magnetite-based receptors provide a component of the navigational ‘map’ (see also Deutschlander et al 2012). At the same time, the data of the respective study (Fig.…”

Section: What Kind Of Information Is Mediated?mentioning

confidence: 97%

The magnetite-based receptors in the beak of birds and their role in avian navigation

Wiltschko

2012

J Comp Physiol A

View full text Add to dashboard Cite

Iron-rich structures have been described in the beak of homing pigeons, chickens and several species of migratory birds and interpreted as magnetoreceptors. Here, we will briefly review findings associated with these receptors that throw light on their nature, their function and their role in avian navigation. Electrophysiological recordings from the ophthalmic nerve, behavioral studies and a ZENK-study indicate that the trigeminal system, the nerves innervating the beak, mediate information on magnetic changes, with the electrophysiological study suggesting that these are changes in intensity. Behavioral studies support the involvement of magnetite and the trigeminal system in magnetoreception, but clearly show that the inclination compass normally used by birds represents a separate system. However, if this compass is disrupted by certain light conditions, migrating birds show ‘fixed direction’ responses to the magnetic field, which originate in the receptors in the beak. Together, these findings point out that there are magnetite-based magnetoreceptors located in the upper beak close to the skin. Their natural function appears to be recording magnetic intensity and thus providing one component of the multi-factorial ‘navigational map’ of birds.

show abstract

Section: What Kind Of Information Is Mediated?mentioning

confidence: 97%

The magnetite-based receptors in the beak of birds and their role in avian navigation

Wiltschko

2012

J Comp Physiol A

View full text Add to dashboard Cite

show abstract

“…Instead, the specificity of effects on experienced adult, and not naive juvenile, migrants supports the interpretation of disruption of a possible map-sense. A recent study on migratory Australian silvereyes (Zosterops l. lateralis) that simulated displacement by changing magnetic intensity signatures indicated that only adult, not juvenile, migrants were affected by the displacement [70]. However, the existence of a magnetic map continues to be strongly debated [1,2,7].…”

Section: What Aspect Of Navigation Is Affected?mentioning

confidence: 99%

A strong magnetic pulse affects the precision of departure direction of naturally migrating adult but not juvenile birds

Holland

Helm

2013

J. R. Soc. Interface.

View full text Add to dashboard Cite

The mechanisms by which migratory birds achieve their often spectacular navigational performance are still largely unclear, but perception of cues from the Earth's magnetic field is thought to play a role. Birds that possess migratory experience can use map-based navigation, which may involve a receptor that uses ferrimagnetic material for detecting gradients in the magnetic field. Such a mechanism can be experimentally disrupted by applying a strong magnetic pulse that re-magnetizes ferrimagnetic materials. In captivity, this treatment indeed affected bearings of adult but not of naive juvenile birds. However, field studies, which expose birds to various navigational cues, yielded mixed results. Supportive studies were difficult to interpret because they were conducted in spring when all age groups navigate back to breeding areas. The present study, therefore, applied a magnetic pulse treatment in autumn to naturally migrating, radio-tagged European robins. We found that, although overall bearings were seasonally correct, orientation of adult but not juvenile robins was compromised by a pulse. Pulsed adults that departed within 10 days of treatment failed to show significant orientation and deviated more from mean migration direction than adult controls and juveniles. Thus, our data give field-based support for a possible ferrimagnetic map-sense during bird migration.

show abstract

“…Magnetoreception can be involved in many aspects of spatial behaviour: as a compass for local and long-distance movements (Wiltschko and Wiltschko, 1972;Landler et al, 2015;Phillips et al, 2013;Diego-Rasilla et al, 2010;Dommer et al, 2008;Freake et al, 2002) as a source of geographic position information (i.e., a magnetic map Phillips, 1986;Philips et al, 1995;Deutschlander et al, 2012) as a reference that reduces errors in path integration (Kimchi et al, 2004;Philips et al, 2010) and potentially as a spherical coordinate system that helps to encode the organism's immediate surrounding and to incorporate local landmark arrays into a global map of familiar space (Landler et al, 2015;Phillips et al, 2010). Consequently, loss of a magnetic sense could impact both long-distance movements (e.g.…”

Section: Introductionmentioning

confidence: 99%

High levels of maternally transferred mercury disrupt magnetic responses of snapping turtle hatchlings (Chelydra serpentina)

Landler

Painter

Coe

et al. 2017

Environmental Pollution

Self Cite

View full text Add to dashboard Cite

a b s t r a c tThe Earth's magnetic field is involved in spatial behaviours ranging from long-distance migration to nongoal directed behaviours, such as spontaneous magnetic alignment (SMA). Mercury is a harmful pollutant most often generated from anthropogenic sources that can bio-accumulate in animal tissue over a lifetime. We compared SMA of hatchling snapping turtles from mothers captured at reference (i.e., low mercury) and mercury contaminated sites. Reference turtles showed radio frequency-dependent SMA along the north-south axis, consistent with previous studies of SMA, while turtles with high levels of maternally inherited mercury failed to show consistent magnetic alignment. In contrast, there was no difference between reference and mercury exposed turtles on standard performance measures. The magnetic field plays an important role in animal orientation behaviour and may also help to integrate spatial information from a variety of sensory modalities. As a consequence, mercury may compromise the performance of turtles in a wide variety of spatial tasks. Future research is needed to determine the threshold for mercury effects on snapping turtles, whether mercury exposure compromises spatial behaviour of adult turtles, and whether mercury has a direct effect on the magnetoreception mechanism(s) that mediate SMA or a more general effect on the nervous system.

show abstract

Age-Dependent Orientation to Magnetically-Simulated Geographic Displacements in Migratory Australian Silvereyes (Zosterops l. lateralis)

Cited by 30 publications

References 26 publications

The magnetite-based receptors in the beak of birds and their role in avian navigation

The magnetite-based receptors in the beak of birds and their role in avian navigation

A strong magnetic pulse affects the precision of departure direction of naturally migrating adult but not juvenile birds

High levels of maternally transferred mercury disrupt magnetic responses of snapping turtle hatchlings (Chelydra serpentina)

Contact Info

Product

Resources

About