Temporal and Spatial Variation in the Diet of the Endemic Lizard Gallotia galloti in an Insular Mediterranean Scrubland

Publication Type:Journal Article
Year of Publication:2008
Authors:Rodríguez, A, Nogales, M, Rumeu, B, Rodríguez, B
Journal:Journal of Herpetology
Volume:42
Issue:2
Date Published:2008
ISBN Number:0022-1511
Keywords:Fringillidae, Serinus, Serinus canaria
Abstract:Abstract We analyzed 621 lizard fecal pellets to assess the diet of the endemic lizard Gallotia galloti (Lacertidae) throughout one year in the thermophilous scrubland, the most threatened habitat in the Canary Islands. Indicating the importance of frugivory, 98.1% of pellets contained seeds from fleshy-fruited plant species (8,028 seeds in total), and the fruit volume reached 47.5%. The Canarian endemic plants Rhamnus crenulata and Canarina canariensis were most important in frequency of occurrence and number of seeds found in pellets, respectively. Lizards were more frugivorous during the summer (63.0% of volume), and seasonal variation was associated with temporal changes in availability of ripe fleshy fruits. We detected microspatial differences in the consumption of fruits and plant material. Significant correlations were found between plant cover of each species and their respective consumption by lizards. Lizards consumed invertebrates throughout the year; Formicidae, Hemiptera, Coleoptera, and Hymenoptera were the most frequently consumed prey (76.5% of the animal prey items). Our results indicate that G. galloti is one of the most frugivorous lacertids studied. The high number of undamaged seeds removed by these lizards also implies an important role in the seed dispersal processes of many fleshy-fruited plant species from this threatened habitat.Abstract We analyzed 621 lizard fecal pellets to assess the diet of the endemic lizard Gallotia galloti (Lacertidae) throughout one year in the thermophilous scrubland, the most threatened habitat in the Canary Islands. Indicating the importance of frugivory, 98.1% of pellets contained seeds from fleshy-fruited plant species (8,028 seeds in total), and the fruit volume reached 47.5%. The Canarian endemic plants Rhamnus crenulata and Canarina canariensis were most important in frequency of occurrence and number of seeds found in pellets, respectively. Lizards were more frugivorous during the summer (63.0% of volume), and seasonal variation was associated with temporal changes in availability of ripe fleshy fruits. We detected microspatial differences in the consumption of fruits and plant material. Significant correlations were found between plant cover of each species and their respective consumption by lizards. Lizards consumed invertebrates throughout the year; Formicidae, Hemiptera, Coleoptera, and Hymenoptera were the most frequently consumed prey (76.5% of the animal prey items). Our results indicate that G. galloti is one of the most frugivorous lacertids studied. The high number of undamaged seeds removed by these lizards also implies an important role in the seed dispersal processes of many fleshy-fruited plant species from this threatened habitat.
URL:http://dx.doi.org/10.1670/07-0752.1
Short Title:Journal of Herpetology
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith