Predation by an exotic lizard,Anolis sagrei, alters the ant community structure in betelnut palm plantations in southern Taiwan

Abstract

Predation by an exotic lizard, Anolis sagrei , alters the ant community structure in betelnut palm plantations in southern TaiwanAbstract . 1. Predators can affect prey directly by reducing prey abundance and indirectly by altering behavioural patterns of prey. From previous studies, there is little evidence that ant community structure is affected by vertebrate predation.2. Researchers tend to consider the interactions between vertebrate predators and ants to be weak. The present study examined the impact of the exotic invasive lizard, Anolis sagrei , on the ant community structure by manipulating the density of lizards within enclosures. The natural density of A. sagrei in the field was surveyed and used as the stocking density rate in the lizard-present sub-enclosures.3. Before the lizard density was manipulated, there was no difference in the ant diversity between sub-enclosures. After the lizard density manipulation, the ant diversity in sub-enclosures with A. sagrei present was significantly different from that of enclosures where the lizards were absent, although the overall ant abundance did not differ significantly.4. The ant diversity difference was generated by a significant reduction of the ant species Pheidole fervens in sub-enclosures with A. sagrei present. Such an abundance change might be the result of direct predation by the lizards, or it might be generated by a foraging site shift by this ant.5. The results of this study thus demonstrated that the invasion of an exotic vertebrate can significantly alter the community structure of ants, perhaps through the combined direct and indirect effects of lizards on ants.

Is Increased Resistance to Parasitism at the Origin of Polygyny in a Mexican Population of the AntEctatomma tuberculatum(Hymenoptera: Formicidae)?

“…However, such environmental factors are known to be important in structuring ant communities and populations. Predation by army ants on other ant species, for example, is thought to be a major factor affecting leaf litter community structure and life-history traits of ant colonies in the neotropics (Kaspari & O'Donnell 2003;O'Donnell et al 2007), while high densities of predators such as larval ant lions (Gotelli 1996) or lizards (Huang et al 2008) can strongly alter ground-foraging ant assemblages. Furthermore, various studies have shown that attacks by parasitoid phorid flies (Feener 2000;Philpott et al 2009), eucharitid wasps (Lachaud & Pérez-Lachaud 2009;Pérez-Lachaud et al 2010), or pathogens (Keller 1995a;Schmid-Hempel 1998;Naug & Camazine 2002) represent another important potential source of disturbance that can affect the composition and dynamics of ant communities as well as colony phenotype.…”

Early post-settlement mortality and the structure of coral assemblages

“…Predation is one of the most important biological processes affecting population dynamics and community structure, especially for species with juveniles or adults with small body sizes (Hixon 1991, Sundell 2006, Huang et al 2008. Heavy predation on early life stages can play a major role in shaping assemblage structure for many organisms, including plants, fish and marine invertebrates (Ostfeld et al 1997, Osman & Whitlatch 2004, Almany & Webster 2006.…”

Predation risk and competitive interactions affect foraging of an endangered refuge‐dependent herbivore

“…Novel predators can increase the predation risk that prey species are exposed to and consequently constrain a prey species' foraging behaviour and therefore its access to resources (Wilder & Rypstra, 2004;Huang, Norval & Tso, 2008). In Australia, introduced foxes Vulpes vulpes have increased predation pressure on a range of native species and have been implicated in the extinction and decline of several mammal species within a critical weight range (35-5500 g) (Burbidge & Mckenzie, 1989;Johnson, Burbidge & Mackenzie, 1989).…”