Advertisement

Naturwissenschaften

, Volume 89, Issue 10, pp 470–473 | Cite as

Tracing the diet of the monitor lizard Varanus mabitang by stable isotope analyses (δ15N, δ13C)

  • Ulrich Struck
  • Alexander V. Altenbach
  • Maren Gaulke
  • Frank Glaw
Short Communication

Abstract.

In this study, we used analyses of stable isotopes of nitrogen (δ15N) and carbon (δ13C) to determine the trophic ecology of the monitor lizard Varanus mabitang. Stable isotopes from claws, gut contents, and soft tissues were measured from the type specimen. Samples from Varanus olivaceus, Varanus prasinus, Varanus salvator, the herbivorous agamid lizard Hydrosaurus pustulatus, and some plant matter were included for comparison. Our data show a rapid decrease in δ13C (about10‰) from food plants towards gut contents and soft tissues of herbivorous species. For the varanids, we found a significant linear correlation of decreasing δ13C and increasing δ15N from herbivorous towards carnivorous species. In terms of trophic isotope ecology, the type specimen of V. mabitang is a strict herbivore. Thus it differs significantly in its isotopic composition from the morphologically next closest related species V. olivaceus. The most highly carnivorous species is V. salvator, while δ15N values for V. prasinus and V. olivaceus are intermediate. Claws provide very valuable samples for such measurements, because they can be sampled from living animals without harm. Additionally, their range of variability is relatively small in comparison with measurements from soft tissues.

Keywords

Soft Tissue Isotopic Composition Stable Isotope Isotope Analysis Food Plant 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag 2002

Authors and Affiliations

  • Ulrich Struck
    • 1
  • Alexander V. Altenbach
    • 1
  • Maren Gaulke
    • 2
  • Frank Glaw
    • 3
  1. 1.GeoBio-Center Ludwig-Maximilans-Universität, Richard-Wagner-Strasse 10, 80333 München, Germany
  2. 2.Philippine Endemic Species Conservation Project, Bodenseestrasse 300, 81249 München, Germany
  3. 3.Zoologische Staatssammlung, Münchhausenstrasse 21, 81247 München, Germany

Personalised recommendations