Oviposition Site Selection Structures Niche Partitioning Among Coccinellid Species in a Tropical Ecosystem

Abstract

The competitive exclusion hypothesis suggests that coexisting related species using similar resources in nature should partition their realized niches. This hypothesis has direct implications for conservation strategies using biological control, taking into consideration the shifts caused by the introduction of natural enemies in a local community. Such introductions typically lead to disruptions in species interactions and interfere with community structure. In this study, we asked whether community structure of aphidophagous lady beetles is determined by the distribution of specific plants and aphids. To answer this question, we describe the distribution patterns of lady beetles (adults, larvae, and egg clusters) relative to plants and aphids in eight crop ecosystems in a central region of Brazil. We used canonical correspondence analysis to evaluate lady beetle distribution relative to selected habitat variables. Cycloneda sanguinea L., Hippodamia convergens Guérin-Méneville, Harmonia axyridis Pallas, and Eriopis connexa Germar (Coleoptera: Coccinellidae) differed in their use of plants and aphids. The association of egg clusters with specific plants/aphids was stronger than that of larvae or adults. In conclusion, lady beetle species occupied different niches, indicating different patterns of habitat use that may facilitate their coexistence in crop ecosystems. Furthermore, immature individuals had more specific environmental associations than adults, likely because female choice of oviposition sites influences their distribution and thus lady beetle community structure.

Behavioral and Immunological Features Promoting the Invasive Performance of the Harlequin Ladybird Harmonia axyridis

“…The distribution of oviposition sites among conspecific females is of prime importance because it allows them to share resources by partitioning their niches (Sicsú et al, 2015). A few laboratory and semi-field studies suggest that H. axyridis is deterred from ovipositing in the presence of conspecifics, whereas heterospecific competitors do not influence oviposition site selection (Yasuda et al, 2000;Almohamad et al, 2010).…”

Lady Beetle Oviposition Site Choices: Maternal Effects on Offspring Performance

“…Most lady beetles are aposematic and their bright colors conspicuously advertise their unpalatability to other predators, particularly birds (Dolenská et al 2009;Arenas et al 2015). Interactions between aphid populations and host plants also are important factors that structure the relative abundance of aphidophagous lady beetles in their assemblages (Sicsú et al 2015).…”

“…In Brazilian heterogeneous agroecosystems, native lady beetles Cycloneda sanguinea (L.), Hippodamia convergens (Guérin-Méneville), Eriopis connexa (Germar), and exotic Harmonia axyridis (Pallas) (all Coleoptera: Coccinellidae) display different habitat use patterns that appear to facilitate their coexistence through niche partitioning (Sicsú et al 2015). The distribution patterns of these populations are closely associated with female oviposition sites, reflecting a strong link between immature stages (eggs and larvae) with specific plants (Sicsú et al 2015). However, few studies have explored the associations between aphidophagous lady beetle oviposition site selection and adequate food resources for offspring as it relates to subsequent fitness.…”

“…Offspring performance is a key element to understand how maternal choices for specific oviposition sites are determinant factors for the survival and reproduction (fitness) of aphidophagous lady beetle offspring. The link between female behavioral choices and offspring performance also has consequences for community structure because this may be associated with the co-occurrence of species through niche partitioning and reduction of intraguild predation (Sicsú et al 2015). Thus, examining lady beetle oviposition site choice effects will enhance our understanding about differential habitat use and coexistence of different species in Brazilian agroecosystems.…”

“…Based on lady beetle interactions formerly observed under field conditions (Sicsú et al 2015), we formulated the following questions:…”