Adult female loggerhead turtles around Japan 1999
Atmosphere and Ocean Research Institute, University of Tokyo

Dataset credit

Hideo Hatase, Atmosphere and Ocean Research Institute, University of Tokyo

Contacts

RoleNameOrganization 
Primary contact Hideo Hatase Atmosphere and Ocean Research Institute, The University of Tokyo (Hatase)
Data entry Ei Fujioka Duke University

Citation

Hatase H, Takai N, Matsuzawa Y, Sakamoto W, Omuta K, Goto K, Arai N, Fujiwara T. 2002. Size-related differences in feeding habitat use of adult female loggerhead turtles Caretta caretta around Japan determined by stable isotope analyses and satellite telemetry. Marine Ecology Progress Series. Vol. 233: 273-281.

Abstract

Stable isotope analyses and satellite telemetry were used to investigate the relationship between the body size and feeding habitat of adult female loggerhead turtles Caretta caretta around Japan. A total of 149 females from 2 nesting sites, 600 km apart, 1 in Minabe and 1 in Yakushima, was examined by stable isotope analyses of the egg-yolk in 1998 and 1999. Since there were neither significant intra- nor inter-clutch variations in δ13C or δ15N egg-yolks from the same female, the isotope signatures of a single egg-yolk from any clutch in a nesting season could be used to represent those of its nesting female. Both isotopic values increased as the body size of the nesting female increased, irrespective of nesting site. Comparisons between isotopic values of loggerhead egg-yolks and prey items revealed size-related differences among both feeding habits (planktonic or benthic) and habitat areas (pelagic or neritic) of female loggerheads. In 1999, 5 females nesting in Minabe were tracked by satellite. After the nesting season, 2 females with low isotopic values migrated to the pelagic Pacific along the Kuroshio Current, whereas 3 with high isotopic values migrated to the neritic East China Sea. The former females were smaller than the latter. These results were consistent with inferences from stable isotope analyses and previous findings, indicating that the body size, habitat area, and feeding habit of female loggerheads around Japan are closely related. In addition, there were no significant differences in δ13C or δ15N between recruits and remigrants, implying that female loggerheads do not change their feeding habitats during the reproductive stage. We postulate that female habitat selection as a function of body size is closely related to the recruitment and settlement in immature loggerheads, which return to Japan after developmental migrations in the North Pacific.

Purpose

N/A

Supplemental information

N/A

References

Hatase H, Takai N, Matsuzawa Y, Sakamoto W, Omuta K, Goto K, Arai N, Fujiwara T. 2002. Size-related differences in feeding habitat use of adult female loggerhead turtles Caretta caretta around Japan determined by stable isotope analyses and satellite telemetry. Marine Ecology Progress Series. Vol. 233: 273-281.

Attributes

Overview

Attributes described below represent those in the original dataset provided by the provider.
Only minimum required attributes are visible and downlodable online. Other attributes may be obtained upon provider's permission unless otherwise noted below.

This section explains attributes included in the original dataset. OBIS-SEAMAP restricts the attributes available to the public to date/time, lat/lon and species names/counts only. Should you need other attributes described here, you are encouraged to contact the data provider.

Attributes in dataset provided

Attribute (table column)Description
oidUnique ID number (generated by OBIS-SEAMAP)
tag_idTag/Turtle ID
obs_dateDate of the recording
obs_timeTime of the recording at UTC
lcLC
latLatitude in decimal degrees
lonLongitude in decimal degrees
sp_tsnTaxonomic Serial Number added by OBIS-SEAMAP
obs_countNumber of animal. Always 1
ageAge
sexSex
carapace_lengthStraight carapace length (mm)
geomGeometry field added by OBIS-SEAMAP
OBIS-SEAMAP ID1656
Seabirds0
Marine mammals0
Sea turtles251
Rays and sharks0
Other species0
Non spatial0
Non species0
Total251
Date, Begin1999-07-20
Date, End2000-01-16
Temporal prec.111110
Latitude28.43 - 40.41
Longitude121.71 - 160.01
Coord. prec.3 decimal digits
PlatformTag
Data typeTelemetry location
TracklinesYES (ID: 1657)
Contr. throughSEAMAP_TO_SWOT
Registered2017-11-17
Updated2017-12-13
StatusPublished
Sharing policy CC-BY-NC (All)
Also availalbe from iOBIS
GBIF (planned)
See metadata in static HTML
See metadata in FGDC XML
See download history / statistics
1