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Prey availability, prey selection, and trophic niche width in the lizard Psammodromus algirus along an elevational
Gregorio Moreno-Rueda1, Elena Melero1, Senda Reguera1
1Departamento de Zoología, Facultad de Ciencias, Universidad de Granada, Granada, Spain.
Current Zoology
|October 17, 2018
Summary
This study shows that the lizard Psammodromus algirus expands its trophic niche with elevation in the Sierra Nevada. Alpine lizards consume more prey types, demonstrating adaptation to harsh mountain environments.
Area of Science:
- Ecology
- Zoology
- Environmental Science
Background:
- Alpine environments present harsh conditions for ectotherms like lizards.
- Environmental variation in mountains can affect prey availability.
- Lizard trophic ecology along elevational gradients remains understudied.
Purpose of the Study:
- To analyze diet, prey availability, prey selection, and trophic niche width of Psammodromus algirus along an elevational gradient.
- To understand how elevation influences lizard trophic ecology in the Sierra Nevada.
- To assess the adaptive capacity of P. algirus to alpine conditions.
Main Methods:
- Analysis of fecal samples to determine lizard diet.
- Pitfall traps used to assess prey abundance and availability.
- Comparison of diet composition with prey availability to determine prey selection and electivity.
- Calculation of trophic niche width at different elevations.
Main Results:
- Orthoptera, Formicidae, Hemiptera, Coleoptera, and Araneae identified as primary prey.
- Prey abundance and diversity increase with elevation.
- Lizards exhibit prey selection, preferring Orthoptera, Hemiptera, and Araneae, while rejecting Formicidae and Coleoptera.
- Trophic niche width expands with elevation, with females having a broader niche than males.
- Consumption of Coleoptera and electivity for Araneae increase with elevation.
Conclusions:
- Psammodromus algirus demonstrates dietary flexibility and expands its trophic niche in alpine habitats.
- The lizard's trophic ecology shifts with elevation, indicating adaptation to varying prey availability.
- P. algirus appears well-adapted to the challenging conditions of alpine environments, maintaining a broad trophic niche.
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