Insectivory in Fijian flying foxes (Pteropodidae)

Abstract

We used scat and isotope analyses to assess insectivory in Fijian flying foxes (Pteropodidae), seeking insights into niche partitioning of co-occurring bat species with high plant diet overlap. Moth scales were most common in scats of Notopteris macdonaldi (87%; P. tonganus: 62%; Pteropus samoensis: 36%) and may indicate shared resources. The small and highly manoeuvrable N. macdonaldi exploited nectar-rich flowers also favoured by moths (e.g. Barringtonia spp.). Other invertebrate remains were most frequent in scats of P. tonganus (69%). On the basis of scat results and ecological observations, P. tonganus uses a combination of insectivory and a highly varied plant diet to obtain sufficient nutrients. Scats of P. samoensis contained few invertebrate remains, but abundant protein-rich plant species (including Freycinetia spp.), and juveniles seemed to consume moths frequently. Clustered d 15 N and d 13 C for N. macdonaldi and P. samoensis indicated a narrower dietary breadth than that of P. tonganus. P. tonganus juveniles appeared at a significantly higher trophic level than did adults, probably the result of milk consumption and/or higher rates of protein synthesis. The methods used detected little evidence that bats partitioned resources vertically. This study generates hypotheses for the further examination of flying-fox diets.

Preference of an insular flying fox for seed figs enhances seed dispersal of a dioecious species

“…, Clulow & Blundell , Scanlon et al . ). Compared with plant material, insects are much richer in protein, which may help maintain and enhance the growth and reproduction of consumers (Rothman et al .…”

“…Regardless, the information obtained in this study is insufficient to conclude whether P. dasymallus consumed the beetles intentionally or incidentally. Insects eaten by nonecholocating pteropodids tend to be easy prey and are characterized by conspicuousness, a large size, slow flight and at least temporary abundance (Funakoshi et al 1993, Barclay et al 2006, Clulow & Blundell 2011, Scanlon et al 2013. Compared with plant material, insects are much richer in protein, which may help maintain and enhance the growth and reproduction of consumers (Rothman et al 2014).…”

The Conflict Between Pteropodid Bats and Fruit Growers: Species, Legislation and Mitigation

“…It comprises 196 species (Simmons 2005) that feed primarily on fruit, flowers (nectar, pollen, petals and bracts) and leaves of at least 188 plant genera from 64 families (Lobova et al 2009;Fleming and Kress 2011), although some species have also been recorded eating insects (e.g. Clulow and Blundell 2011;Scanlon et al 2013). Fujita (1988) and Fujita and Tuttle (1991) used the term 'flying foxes' to refer to all bats in the family Pteropodidae, but we restrict this term to the 70 species in the genera Pteropus and Acerodon (IUCN 2014), following the definition outlined by Kingston (2010), and use the term 'fruit bats' for the remainder.…”

Response of primary and secondary rainforest flowers and fruits to a cyclone, and implications for plant‐servicing bats

“…to be cyclone‐resistant, but unlike in Samoa (Cox, ) P. tonganus readily used this resource and all bat species used Syzygium flowers. P. tonganus has the greatest dietary breadth of all Fijian bat species (Scanlon & Petit, ; Scanlon et al., , ) and more capacity to switch resources, even tracking resources among islands (McConkey & Drake, ). The dramatic cyclone‐related population declines recorded for Pteropus spp.…”

“…The hypanthium of S. oblongifolium bears numerous pink stamens and a nectar reward; flowers are 1–2 cm diameter, and are bat‐ and moth‐pollinated (based on observations of Syzygium at the site; e.g. Scanlon & Petit, ; Scanlon, Petit, & Sternberg, ; Scanlon et al., ). Gironniera celtidifolia has short, dense, many‐flowered panicles (~4–5 cm diameter) with no corolla (Whistler, ).…”