iHerp Australia Issue 9 | Page 12

The Noronha Skink (Galliotta atlantica) consumes fruits of the plant Lycium intricatum, and is in turn eaten by the Great Grey Shrike (Lanius excubitor). Image by Simone Giachello. meridionalis) and the Common Kestrel (Falco tinnuncu- lus). Moreover, shrikes and kestrels have different habitat preferences, so this combination of direct and indirect dispersal ensures seeds are deposited in a variety of environments. Researchers found that seeds were present in just 7.3% of G. atlantica droppings, but 31% of kestrel pellets, and over 55.7% of shrike regurgitations. The percentage of viable seeds, percentage germination and germination rate were all highest from shrike regurgitations, followed by lizard scats, but significantly lower in kestrel pellets. So whilst ‘secondary’ dispersal is enhanced by the shrikes, kestrel predation has an overall negative net effect, since it entails both the consumption of legitimate direct seed dispersal agents (the lizards) and reduced germination of seeds acquired from their lizard prey. 2 x qtr page ads