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We investigated the reproductive ecology and effects of egg parasitism on the Samoan swallowtail butterfly (Papilio godeffroyi), which survives only on Tutuila Island, American Samoa, after having disappeared from the much larger islands of Upolu and Savai'i in independent Samoa. During monthly surveys of its only known host plant, Micromelum minutum, across eight sites in 2013 and 2014, we collected eggs, eggshells, larvae, pupae, and pupal exuviae. Live specimens were reared under laboratory conditions to determine reproductive outcomes, developmental rates, and sex ratios, as well as parasitoid attack frequencies, brood sizes, and sex ratios. Sixty‐six of 448 (14.7%) eggs produced larvae, 47 of which became adults. The sex ratio was approximately even overall and within each developmental stage. Eggs were slightly larger on individual host trees and in host tree stands that yielded more eggs per unit of foliage, indicating that ovipositing females responded to some features of host trees and stands. Eggs hatching female or male larvae were similar in size, and the sexes developed at similar rates. A newly described species of parasitoid wasp, Ooencyrtus pitosina (Encyrtidae), emerged from 73.6% of 382 butterfly eggs that failed to hatch in the laboratory (62.7% of 448 eggs overall). Forty‐one other eggs contained dead parasitoid larvae. An additional, unidentified Ooencyrtus wasp species emerged from a single P. godeffroyi egg. No parasitoids were reared from P. godeffroyi larvae or pupae. Of 656 P. godeffroyi eggshells collected in the field and examined in the laboratory, 62.2% showed signs of having been parasitized by O. pitosina. There was no evidence that parasitism rates were density‐dependent. O. pitosina brood sizes ranged from 1 to 5, with the sex ratio skewed toward females (2.40 F:1.00 M). Larger parasitoid broods were associated with slightly larger host eggs, indicating that female wasps may adjust brood size according to host egg size or that fewer wasp larvae are able to complete development in smaller eggs. Techniques used to rear both P. godeffroyi and O. pitosina in the laboratory could be applied to a captive‐rear, wild‐release program, which may facilitate reestablishment of the species in Samoa. [ABSTRACT FROM AUTHOR]

The Samoan swallowtail butterfly (Papilio godeffroyi) has become restricted to Tutuila Island, American Samoa. Factors driving its extirpation on other islands may be partly due to the availability and suitability of habitat, given the singular association we observed of P. godeffroyi with its host plant, Micromelum minutum. We expected that as a host plant specialist, P. godeffroyi might respond to variation in the physical traits and habitat context of M. minutum, which could help identify conservation opportunities throughout its present and former range. Because the ecology of P. godeffroyi is largely unknown, we conducted systematic surveys during 15 months in 2013 and 2014 on Tutuila to investigate its reproductive response to the physical and phenological variability of individual host trees and to the structural and geographical variability of the stands in which they occurred. We searched foliage for eggs, larvae, and pupae and monitored seasonal trends in herbivory and production of leaves, flowers, and fruits on 117 host trees in 8 rainforest stands, mostly within the National Park of American Samoa (NPSA), starting in March 2013 and ending in August 2014. We observed high variability in butterfly reproductive output between individual trees and stands, due largely to a strong negative relationship between leaf biomass (at both tree and stand levels) and oviposition density (number of eggs per foliar biomass) and frequency (number of eggs per survey). Distribution patterns of larvae and pupae were less distinct but generally followed trends in oviposition. Our findings indicate that the butterfly is reproducing widely across Tutuila and is likely to respond positively to management to increase the availability of small host trees in low‐density stands. Thus, the species is a good candidate for conservation management focusing on habitat. [ABSTRACT FROM AUTHOR]

Questions: The effects of agriculture on forest biodiversity and ecosystem properties can persist decades or centuries after abandonment. Many Pacific island nations are experiencing declines in traditional agriculture. Seed dispersal and seedling recruitment are critical to forest regeneration, and this is particularly relevant for Polynesia where native seed disperser diversity is low and species have been extirpated to crisis levels. In this study we asked: are secondary lowland tropical forests converging to mature forest, and are there seedling recruitment and survival differences between forest types? Location: The Polynesian island of Tutuila, American Samoa, where traditional agriculture has been on the decline since the 1940s and secondary forests comprise 70% of all forest area. Methods: We surveyed 34 vegetation plots (containing 2,232 adult trees and 6,579 tree seedlings) across mature forest and >50 years old secondary lowland rain forest. We quantitatively compared forest diversity, structure and the 3-year seedling regeneration dynamics of the tree community. Results: Although species richness and stem densities were similar between mature and secondary forest, most diversity and structure parameters remained distinguishable between the two forest types. Basal area remained significantly higher in mature forest; the diagnostic tree species of mature and secondary forest differed; and community composition (as indicated by NMDS) remained significantly different. However, seedling survivorship did not differ between forest types and seedling recruitment patterns indicated that there remained a suite of effective seed dispersers on Tutuila. Conclusions: We conclude that (a) community differences between mature and secondary lowland rainforest were driven by the abundance of diagnostic species rather than exclusion of species from a forest type, and (b) there was no evidence of biophysical or ecological barriers to forest recovery of lowland secondary rain forest, or its convergence towards mature lowland rain forest. Nevertheless, more than 50 years after agricultural abandonment, secondary forest remains distinct from mature forest, highlighting that land use legacies are long-term drivers of forest composition and successional trajectory in post-agricultural landscapes of Polynesia. [ABSTRACT FROM AUTHOR]

A study was conducted to determine the day-roost selection of evening bats (Nycticeius humeralis) at multiple scales in mature longleaf (Pinus palustirs; natural) and intensely managed loblolly pine (P.taeda; managed) landscapes in the Gulf Coastal Plain of Georgia, USA. It was found that the evening bats in the natural habitats with more number of rooting structures, selected day-roosts with favorable landscape features like nearness to water and foraging sites and benefits like less traveling costs while the bats on the managed sites chose day-roosts only at the tree and plot scale.

The article presents a study on the distribution and seed dispersal of sycamore figs, Ficus sycomorus, based on the foraging movements of two species of epauletted fruit bats in Kruger National Park, South Africa. Radio-tagged Epomophorus crypturus and Epomophorus wahlbergi activity were found to be concentrated within riparian forests having sycamore figs present. Interdependence between the figs and the two species of fruit bats which follow the distribution of available ripe figs are noted.

Occupancy analysis and its ability to account for differential detection probabilities is important for studies in which detecting echolocation calls is used as a measure of bat occurrence and activity. We examined the feasibility of remotely acquiring bat encounter histories to estimate detection probability and occupancy. We used echolocation detectors coupled to digital recorders operating at a series of proximate sites on consecutive nights in 2 trial surveys for the Hawaiian hoary bat (Lasiurus cinereus semotus). Our results confirmed that the technique is readily amenable for use in occupancy analysis. We also conducted a simulation exercise to assess the effects of sampling effort on parameter estimation. The results indicated that the precision and bias of parameter estimation were often more influenced by the number of sites sampled than number of visits. Acceptable accuracy often was not attained until at least 15 sites or 15 visits were used to estimate detection probability and occupancy. The method has significant potential for use in monitoring trends in bat activity and in comparative studies of habitat use. [ABSTRACT FROM AUTHOR]