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Juvenile Osprey Navigation during Trans-Oceanic Migration.

Horton TW, Bierregaard RO, Zawar-Reza P, Holdaway RN, Sagar P - PLoS ONE (2014)

Bottom Line: Although some species of bird, fish, insect, mammal, and reptile are capable of drift compensation, our understanding of the spatial reference frame, and associated coordinate space, in which these navigational behaviors occur remains limited.These results are best explained by extreme navigational precision in an exogenous spatio-temporal reference frame, such as positional orientation relative to Earth's magnetic field and pacing relative to an exogenous mechanism of keeping time.Through integration of movement and meteorological data, we propose a new theoretical framework, chord and clock navigation, capable of explaining the precise spatial orientation and temporal pacing performed by juvenile ospreys during their long-distance migrations over open ocean.

View Article: PubMed Central - PubMed

Affiliation: Department of Geological Science, University of Canterbury, Christchurch, New Zealand.

ABSTRACT
To compensate for drift, an animal migrating through air or sea must be able to navigate. Although some species of bird, fish, insect, mammal, and reptile are capable of drift compensation, our understanding of the spatial reference frame, and associated coordinate space, in which these navigational behaviors occur remains limited. Using high resolution satellite-monitored GPS track data, we show that juvenile ospreys (Pandion haliaetus) are capable of non-stop constant course movements over open ocean spanning distances in excess of 1500 km despite the perturbing effects of winds and the lack of obvious landmarks. These results are best explained by extreme navigational precision in an exogenous spatio-temporal reference frame, such as positional orientation relative to Earth's magnetic field and pacing relative to an exogenous mechanism of keeping time. Given the age (<1 year-old) of these birds and knowledge of their hatching site locations, we were able to transform Enhanced Magnetic Model coordinate locations such that the origin of the magnetic coordinate space corresponded with each bird's nest. Our analyses show that trans-oceanic juvenile osprey movements are consistent with bicoordinate positional orientation in transformed magnetic coordinate or geographic space. Through integration of movement and meteorological data, we propose a new theoretical framework, chord and clock navigation, capable of explaining the precise spatial orientation and temporal pacing performed by juvenile ospreys during their long-distance migrations over open ocean.

No MeSH data available.


Related in: MedlinePlus

Vertical plane bicoordinate geomagnetic space in the Western Atlantic Ocean region.Polar (A, C) and Cartesian (B, D) plots of geomagnetic field coordinates for a 0.5° latitude-longitude grid between 20° and 42° north latitude and −67° and −78° west longitude (A, B; n = 1035) and all of the one-hourly juvenile osprey GPS-enabled PTT tag locations we report (C, D; n = 244 locations from ten birds). The {0;0} coordinate space origin in all panels corresponds with the subcrustal origin of Earth's main magnetic field.
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pone-0114557-g007: Vertical plane bicoordinate geomagnetic space in the Western Atlantic Ocean region.Polar (A, C) and Cartesian (B, D) plots of geomagnetic field coordinates for a 0.5° latitude-longitude grid between 20° and 42° north latitude and −67° and −78° west longitude (A, B; n = 1035) and all of the one-hourly juvenile osprey GPS-enabled PTT tag locations we report (C, D; n = 244 locations from ten birds). The {0;0} coordinate space origin in all panels corresponds with the subcrustal origin of Earth's main magnetic field.

Mentions: The magnetic field experienced at or near the Earth's surface is constantly changing in both space and time due to secular variation in the Main Field (>90% of the total field intensity), interactions with the unpredictable and temporally dynamic interplanetary magnetic field (largely of solar origin and as large as 10% of the total field intensity) and the crustal anomaly field (<1% of the total field intensity). The seven elements include: F, the total field intensity measured in nanotesla (SI) or gauss (CGS); D, the declination angle measured positive to the east of true north; I, the inclination angle measured positive in the downward direction relative to horizontal; H, the horizontal component of the total field intensity; X, the north-south component of H measured positive to the north; Y, the east-west component of H measured positive to the east; Z, the vertical component of the total field intensity measured positive in the downward direction. X, Y, and Z define a three-dimensional Cartesian coordinate space, whereas F, I, and D define a three-dimensional spherical coordinate space. The bicoordinate F-I space is polar by definition and is equivalent to the two-dimensional H-Z Cartesian coordinate space (see also Figure 7).


Juvenile Osprey Navigation during Trans-Oceanic Migration.

Horton TW, Bierregaard RO, Zawar-Reza P, Holdaway RN, Sagar P - PLoS ONE (2014)

Vertical plane bicoordinate geomagnetic space in the Western Atlantic Ocean region.Polar (A, C) and Cartesian (B, D) plots of geomagnetic field coordinates for a 0.5° latitude-longitude grid between 20° and 42° north latitude and −67° and −78° west longitude (A, B; n = 1035) and all of the one-hourly juvenile osprey GPS-enabled PTT tag locations we report (C, D; n = 244 locations from ten birds). The {0;0} coordinate space origin in all panels corresponds with the subcrustal origin of Earth's main magnetic field.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4262435&req=5

pone-0114557-g007: Vertical plane bicoordinate geomagnetic space in the Western Atlantic Ocean region.Polar (A, C) and Cartesian (B, D) plots of geomagnetic field coordinates for a 0.5° latitude-longitude grid between 20° and 42° north latitude and −67° and −78° west longitude (A, B; n = 1035) and all of the one-hourly juvenile osprey GPS-enabled PTT tag locations we report (C, D; n = 244 locations from ten birds). The {0;0} coordinate space origin in all panels corresponds with the subcrustal origin of Earth's main magnetic field.
Mentions: The magnetic field experienced at or near the Earth's surface is constantly changing in both space and time due to secular variation in the Main Field (>90% of the total field intensity), interactions with the unpredictable and temporally dynamic interplanetary magnetic field (largely of solar origin and as large as 10% of the total field intensity) and the crustal anomaly field (<1% of the total field intensity). The seven elements include: F, the total field intensity measured in nanotesla (SI) or gauss (CGS); D, the declination angle measured positive to the east of true north; I, the inclination angle measured positive in the downward direction relative to horizontal; H, the horizontal component of the total field intensity; X, the north-south component of H measured positive to the north; Y, the east-west component of H measured positive to the east; Z, the vertical component of the total field intensity measured positive in the downward direction. X, Y, and Z define a three-dimensional Cartesian coordinate space, whereas F, I, and D define a three-dimensional spherical coordinate space. The bicoordinate F-I space is polar by definition and is equivalent to the two-dimensional H-Z Cartesian coordinate space (see also Figure 7).

Bottom Line: Although some species of bird, fish, insect, mammal, and reptile are capable of drift compensation, our understanding of the spatial reference frame, and associated coordinate space, in which these navigational behaviors occur remains limited.These results are best explained by extreme navigational precision in an exogenous spatio-temporal reference frame, such as positional orientation relative to Earth's magnetic field and pacing relative to an exogenous mechanism of keeping time.Through integration of movement and meteorological data, we propose a new theoretical framework, chord and clock navigation, capable of explaining the precise spatial orientation and temporal pacing performed by juvenile ospreys during their long-distance migrations over open ocean.

View Article: PubMed Central - PubMed

Affiliation: Department of Geological Science, University of Canterbury, Christchurch, New Zealand.

ABSTRACT
To compensate for drift, an animal migrating through air or sea must be able to navigate. Although some species of bird, fish, insect, mammal, and reptile are capable of drift compensation, our understanding of the spatial reference frame, and associated coordinate space, in which these navigational behaviors occur remains limited. Using high resolution satellite-monitored GPS track data, we show that juvenile ospreys (Pandion haliaetus) are capable of non-stop constant course movements over open ocean spanning distances in excess of 1500 km despite the perturbing effects of winds and the lack of obvious landmarks. These results are best explained by extreme navigational precision in an exogenous spatio-temporal reference frame, such as positional orientation relative to Earth's magnetic field and pacing relative to an exogenous mechanism of keeping time. Given the age (<1 year-old) of these birds and knowledge of their hatching site locations, we were able to transform Enhanced Magnetic Model coordinate locations such that the origin of the magnetic coordinate space corresponded with each bird's nest. Our analyses show that trans-oceanic juvenile osprey movements are consistent with bicoordinate positional orientation in transformed magnetic coordinate or geographic space. Through integration of movement and meteorological data, we propose a new theoretical framework, chord and clock navigation, capable of explaining the precise spatial orientation and temporal pacing performed by juvenile ospreys during their long-distance migrations over open ocean.

No MeSH data available.


Related in: MedlinePlus