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It is estimated that more than 500 species of insects have been introduced to the Galápagos Islands via human activities. One of these insect invaders is the yellow paper wasp, Polistes versicolor (Olivier) (Hymenoptera: Vespidae), a social wasp native to continental South America. In Galápagos, these wasps are voracious predators of insect larvae, compete with native species for insect prey or for floral resources and are a human nuisance. Wasp suppression methods currently in use are inefficient and attract non-target species, calling for the development of species-specific attractants that can be used in baits to lure and kill wasps. To evaluate the potential for using wasp semiochemicals in baits, we determined the biochemical composition of the head, thorax, Dufour’s and venom glands of P. versicolor foragers via gas chromatography/mass spectrometry (GC/MS). Male and female wasps were tested for behavioral responses to body segment extracts from both sexes. Female body extracts consistently elicited more behavioral responses in both male and female wasps than male extracts. Females reacted to female head, thorax and abdomen (the Dufour’s and venom glands are located in the abdomen) extracts, whereas males reacted significantly to female head and thorax extracts. One male body extract, the head, elicited two significant behaviors: female wasps groomed more often, and males touched the filter paper more often compared to the blank control. Head extracts consistently changed the behavior of female and male wasps and, together with female thorax extracts, have potential as species-specific lures for yellow paper wasps. Heads were mainly composed of hydrocarbon lipids and oleamide, a ligand for odorant-binding proteins. The thorax consisted of fatty aldehydes, long-chain alkanes and fatty amide lipids. Field trials of blends of these compounds in high wasp density areas of Galápagos are the next step to confirm if any of these compounds are attractive to P. versicolor.

Invasive species are one of the greatest threats to biodiversity, with endemic species on islands being at particular risk. Management programs can help to minimize these impacts, but such programs are most successful when they are well-informed. In the Galapagos Islands, Ecuador, a recently introduced avian parasitic fly, Philornis downsi, has had strong negative effects on the survival of multiple endemic bird species, including several species of Darwin’s finches. The fly now populates most of the major islands within the Archipelago and the need to better understand the population structure and connectivity patterns of this invasive fly has become increasingly apparent as various management efforts are being considered. Here, we use genomic and phylogenetic approaches to estimate population structure and connectivity for P. downsi collected from five islands within the Galapagos Islands and several sites in mainland Ecuador, which is the presumptive origin of the invasive population. Genomic data showed very little genetic differentiation between island populations of P. downsi relative to the mainland. Phylogenetic analyses, which used more conservative genetic markers than the genomics approach, showed that island and mainland populations of flies were highly related. Our study provides some of the first results using genetic data to quantify differentiation among mainland and island populations of P. downsi. In addition, our study found very little genetic differentiation between island populations of flies, suggesting that there may be considerable gene flow among islands; however, further sampling is needed to determine the extent to which this could be occurring. As management techniques aimed at controlling the impact of this parasite on endemic bird populations are being considered, our study provides important insights into the history of P. downsi’s invasion to the Galapagos Islands and current population connectivity patterns.

The yellow paper wasp, Polistes versicolor (Olivier) was first recorded in the Galapagos archipelago in 1988. Its life cycle and ecological impacts were studied on two islands 11 yr after it was first discovered. This invasive wasp adapted quickly and was found in most environments. Colony counts and adult wasp monitoring showed a strong preference for drier habitats. Nest activities were seasonally synchronized, nest building followed the rains in the hot season (typically January–May), when insect prey increases, and peaked as temperature and rains started to decline. Next, the number of adult wasps peaked during the cool season when there is barely any rain in the drier zones. In Galapagos, almost half of the prey loads of P. versicolor were lepidopteran larvae, but wasps also carried spiders, beetles, and flies back to the colonies. An estimated average of 329 mg of fresh insect prey was consumed per day for an average colony of 120–150 wasp larvae. The wasps preyed upon native and introduced insects, but likely also affect insectivorous vertebrates as competitors for food. Wasps may also compete with native pollinators as they regularly visited flowers to collect nectar, and have been recorded visiting at least 93 plant species in Galapagos, including 66 endemic and native plants. Colonies were attacked by a predatory moth, Taygete sphecophila (Meyrick) (Lepidoptera: Autostichidae), but colony development was not arrested. High wasp numbers also affect the activities of residents and tourists. A management program for this invasive species in the archipelago is essential.

CRISPR gene drives have potential for widespread and cost-efficient pest control, but are highly controversial. We examined a potential gene drive targeting spermatogenesis to control the invasive common wasp (Vespula vulgaris) in New Zealand. Vespula wasps are haplodiploid. Their life cycle makes gene drive production challenging, as nests are initiated by single fertilized queens in spring followed by several cohorts of sterile female workers and the production of reproductives in autumn. We show that different spermatogenesis genes have different levels of variation between introduced and native ranges, enabling a potential ‘precision drive’ that could target the reduced genetic diversity and genotypes within the invaded range. In vitro testing showed guide-RNA target specificity and efficacy that was dependent on the gene target within Vespula, but no cross-reactivity in other Hymenoptera. Mathematical modelling incorporating the genetic and life history traits of Vespula wasps identified characteristics for a male sterility drive to achieve population control. There was a trade-off between drive infiltration and impact: a drive causing complete male sterility would not spread, while partial sterility could be effective in limiting population size if the homing rate is high. Our results indicate that gene drives may offer viable suppression for wasps and other haplodiploid pests.

Invasive species cause severe ecological and economic impacts in their introduced ranges. Vespula wasps, native to Eurasia, are a major threat to New Zealand native ecosystems. Understanding factors that influence the success of wasp invasion is pivotal for the development of control strategies. Here, we compare genetic diversity and structure of Vespula germanica and Vespula vulgaris between regions of their native and introduced ranges using microsatellite markers. Our study found lower diversity and lack of genetic structure for both invasive Vespula species within New Zealand. The significant reduction in allelic richness, gene diversity and effective population size illustrate a major bottleneck in New Zealand V. germanica and V. vulgaris populations. Strong signatures of population structure were found for both Vespula species with two clusters being identified as optimal k, approximately corresponding to the native and the invaded ranges. Our results highlight the fact that the lack of genetic diversity does not impede successful invasions in V. germanica and V. vulgaris and encourage further research into mechanisms that promote the success of invasive social insects. Overall, this study provides insights into the genetics of invasive Vespula wasps that can be useful for the development of efficient management strategies.

The survival of parasites is threatened directly by environmental alteration and indirectly by all the threats acting upon their hosts, facing coextinction. The fate of Darwin's finches and their native ectoparasites in the Galapagos Islands is uncertain because of an introduced avian parasitic fly, Philornis downsi, which could potentially drive them to extinction. We documented all known native ectoparasites of Darwin's finches. Thirteen species have been found: nine feather mites, three feather lice and one nest mite. No ticks or fleas have been recorded from them yet. Management options being considered to control P. downsi include the use of the insecticide permethrin in bird nests which would not only kill the invasive fly larvae but the birds’ native ectoparasites too. Parasites should be targeted for conservation in a manner equal to that of their hosts. We recommend steps to consider if permethrin-treated cotton stations are to be deployed in the Galapagos archipelago to manage P. downsi.

The declining-population paradigm holds that small populations are particularly vulnerable to anthropogenic influences such as habitat destruction, pollution and species introductions. While the effects of particular stressors, such as parasitism, may be unimportant in a large, healthy population, they can be serious and even devastating in situations characterized by a restricted geographic range, or by fragmented or reduced population sizes. We apply this idea to nest parasitism of threatened Neotropical bird species that exist in small populations, focusing on dipteran nest parasites in the genus Philornis. We review the literature on Philornis parasitism exerting negative pressure on bird populations that have become small and isolated due to human actions and present a new case of Philornis parasitism of a threatened hummingbird species. Our aim is to raise awareness about the exacerbating effect that nest parasites can have on small and declining bird populations; especially when biological information is scarce. The five reviewed cases involve two species of Darwin?s Finches in the Galápagos Islands attacked by the invasive P. downsi, two species of hawks on islands in the Caribbean attacked by the native P. pici and P. obscura, and the Yellow Cardinal (Gubernatrix cristata) in southern South America attacked by an unknown Philornis species. We also present new documentation of parasitism of a threatened hummingbird species in mainland Ecuador by an unidentified Philornis species. We recommend more field studies to determine the presence of nest parasites in bird populations worldwide to improve understanding how nest parasites affect bird fitness and population viability and to allow time to act in advance if needed. Parasitism by Philornis may represent a severe mortality factor in most already threatened bird species, putting them at greater risk of extinction. Therefore, parasitism management should be included in all threatened species recovery plans. Fil: Bulgarella, Mariana. Victoria University Of Wellington; Fil: Quiroga, Martin Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentina Fil: Heimpel, George E.. University of Minnesota; Estados Unidos

Parasite host range can be influenced by physiological, behavioral, and ecological factors. Combining data sets on host-parasite associations with phylogenetic information of the hosts and the parasites involved can generate evolutionary hypotheses about the selective forces shaping host range. Here, we analyzed associations between the nest-parasitic flies in the genus Philornis and their host birds on Trinidad. Four of ten Philornis species were only reared from one species of bird. Of the parasite species with more than one host bird species, P. falsificus was the least specific and P. deceptivus the most specific attacking only Passeriformes. Philornis flies in Trinidad thus include both specialists and generalists, with varying degrees of specificity within the generalists. We used three quantities to more formally compare the host range of Philornis flies: the number of bird species attacked by each species of Philornis, a phylogenetically informed host specificity index (Poulin and Mouillot's S TD), and a branch length-based S TD. We then assessed the phylogenetic signal of these measures of host range for 29 bird species. None of these measures showed significant phylogenetic signal, suggesting that clades of Philornis did not differ significantly in their ability to exploit hosts. We also calculated two quantities of parasite species load for the birds - the parasite species richness, and a variant of the S TD index based on nodes rather than on taxonomic levels - and assessed the signal of these measures on the bird phylogeny. We did not find significant phylogenetic signal for the parasite species load or the node-based S TD index. Finally, we calculated the parasite associations for all bird pairs using the Jaccard index and regressed these similarity values against the number of nodes in the phylogeny separating bird pairs. This analysis showed that Philornis on Trinidad tend to feed on closely related bird species more often than expected by chance.

Philornis downsi (Dodge and Aitken) is a bird-parasitic muscid fly native to mainland South America that recently invaded the Galapagos Islands where it is parasitizing Darwin's finches and other land birds. This parasite was previously known only from Argentina, Brazil, and Trinidad and Tobago. The first report of P. downsi from mainland Ecuador is provided, supporting the hypothesis that the invasion route of P. downsi from its native range to the Galapagos Islands includes mainland Ecuador. Four different morphologies of pupal exuviae, which belong to different fly species, were uncovered. Dipteran puparia were found in 20% of naturally occurring nests collected in 2013 and in 27% of nests in 2014 at the two sites in western Ecuador. P. downsi accounted for 74% and 40% of the puparia in 2013 and 2014, respectively. Two new bird host species for the genus Philornis were recorded: the streak-headed woodcreeper (Lepidocolaptes souleyetii) and the fasciated wren (Campylorhynchus fasciatus). The le...

Populations of the same species inhabiting distinct localities experience different ecological and climatic pressures that might result in differentiation in traits, particularly those related to temperature. We compared metabolic rate (and its thermal sensitivity), growth rate, and body size among nine high- and low-elevation populations of the Wellington tree weta, Hemideina crassidens, distributed from 9 to 1171 m a.s.l across New Zealand. Our results did not indicate elevational compensation in metabolic rates (metabolic cold adaptation). Cold acclimation decreased metabolic rate compared to warm-acclimated individuals from both high- and low-elevation populations. However, we did find countergradient variation in growth rates, with individuals from high-elevation populations growing faster and to a larger final size than individuals from low-elevation populations. Females grew faster to a larger size than males, although as adults their metabolic rates did not differ significantly. The combined physiological and morphological data suggest that high-elevation individuals grow quickly and achieve larger size while maintaining metabolic rates at levels not significantly different from low-elevation individuals. Thus, morphological differentiation among tree weta populations, in concert with genetic variation, might provide the material required for adaptation to changing conditions.

Aim Species’ responses to climate change are likely to depend on their ability to overcome abiotic constraints as well as on the suite of species with which they interact. Responses to past climate change leave genetic signatures of range expansions and shifts, allowing inferences to be made about species’ distributions in the past, which can improve our ability to predict the future. We tested a hypothesis of ongoing range shifting associated with climate change and involving interactions of two species inferred to exclude each other via competition. Location New Zealand. Methods The distributions of two tree weta species (Hemideina crassidens and H. thoracica) were mapped using locality records. We inferred the likely modern distribution of each species in the absence of congeneric competitors with the software Maxent. Range interaction between the two species on an elevational gradient was quantified by transect sampling. Patterns of genetic diversity were investigated using mitochondrial DNA, and hypotheses of range shifts were tested with population genetic metrics. Results The realized ranges of H. thoracica and H. crassidens were narrower than their potential ranges, probably due to competitive interactions. Upper and lower elevational limits on Mount Taranaki over 15 years revealed expansion up the mountain for H. thoracica and a matching contraction of the low elevation limits of the range of H. crassidens. The observed nucleotide diversity in H. thoracica was consistent with a species that persisted in northern areas during Pleistocene glacial periods, from where it expanded at warmer times. In contrast, a two-tailed distribution of nucleotide diversity in H. crassidens was as expected for a species that expanded northwards during glacials and southwards during interglacials.

Sheldgeese of the genus Chloephaga are waterfowl (Anatidae) endemic to mainland South America and the Falkland Islands (Malvinas). Continental populations of three species C. picta, C. poliocephala, and C. rubidiceps breed in Patagonia and Tierra del Fuego and migrate northwards to winter in central Argentina and Chile. These continental populations have declined by > 50% in the past 30 years due to direct hunting to control crop damage and by the introduction of the grey fox Dusicyon griseus to their breeding grounds in Tierra del Fuego. The continental population of C. rubidiceps is critically endangered, estimated to be < 1,000 individuals. While no historic population size estimates exist for C. rubidiceps in its wintering grounds, the breeding population in Tierra del Fuego was estimated to number several thousand individuals in the 1950s. In contrast, the C. rubidiceps population in the Falkland Islands (Malvinas) is non-migratory and stable with > 42,000 individuals, as is the Falkland Islands (Malvinas) population of C. picta leucoptera with > 138,000 individuals. Here we use sequence data from the mitochondrial DNA control region to quantify genetic divergence between insular and continental populations of these two species of sheldgeese. Chloephaga rubidiceps and C. picta showed significant intraspecific differentiation of 1.0% and 0.6%, respectively. In both cases, mainland and insular populations were reciprocally monophyletic and did not share mtDNA haplotypes. These results suggest that the insular and continental populations of C. rubidiceps and C. picta are genetically distinct and that female-mediated gene flow is restricted. We recommend a reevaluation of the threat category status of the continental C. rubidiceps population, under IUCN guidelines. It is necessary to implement urgent actions for the conservation of this critically endangered population. Fil: Bulgarella, Mariana. Massey University; Nueva Zelanda Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Di Giacomo, Adrian Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina Fil: Matus, Ricardo. Centro de Rehabilitación Leñadura; Chile Fil: Blank, Viviana Claudia. Centro de Rehabilitación Leñadura; Chile Fil: Wilson, Robert E.. University of Alaska Fairbanks; Estados Unidos Fil: McCracken, Kevin G.. University of Alaska Fairbanks; Estados Unidos

Aim The Malvinas/Falkland Islands (MFI) constitute the largest archipelago inthe southern Atlantic, and harbour endemic lineages that presumably evolvedafter sea-level rise, associated with glacial periods, isolated ancestral popula-tions. We investigate the role of the MFI in isolating populations from conti-nental counterparts of two highly vagile species: the sheldgeese Chloephagapicta and Chloephaga rubidiceps.Location Patagonia and the Malvinas/Falkland Islands.Methods We sampled C. picta and C. rubidiceps on the continent and MFI.Using a reduced-representation genomic approach, we quantified the geneticdifferentiation between insular and continental populations of both species,and used coalescent-based analyses to model their demography.Results The MFI harbour independently evolving lineages of C. picta andC. rubidiceps, which diverged from their continental counterparts during theMiddle-Late Pleistocene and have since experienced negligible gene flow.Main conclusions The c. 450 km that separate the archipelago from thecontinent are sufficient to isolate populations of these putatively highly vagilespecies. Ancestral lineages may have reached the MFI refugium during glacialcycles. Without conservation measures, the drastic decline of the morphologi-cally, behaviourally and ecologically distinct continental population ofC. rubidiceps,to< 1000 individuals, may lead to the extinction of an indepen-dently evolving taxon. Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Campagna, Leonardo. Cornell University; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Di Giacomo, Adrian Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Wilson, Robert E.. University Of Alaska; Estados Unidos Fil: Bulgarella, Mariana. University of Minnesota; Estados Unidos Fil: Petracci, Pablo. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Grupo de Estudios en Conservación y Manejo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Mazar Barnett, Juan. Asociación de Ornitología del Plata; Argentina Fil: Matus, Ricardo. Centro de Rehabilitación de aves Leñadura; Chile Fil: Blank, Olivia. Centro de Rehabilitación de aves Leñadura; Chile Fil: McCracken, Kevin G.. University Of Alaska; Estados Unidos

We examined the genetic structuring of rengarenga (Arthropodium cirratum; Asparagaceae), an endemic New Zealand coastal herb, using nuclear microsatellite markers. This species was brought into cultivation by Māori within the last 700-800 years for its edible roots and was transplanted beyond its natural distribution as part of its cultivation. We found very high levels of genetic structuring in the natural populations (FST = 0.84), indicating low levels of gene flow. Reduced genetic diversity was found in the translocated populations, suggesting a large loss of genetic diversity early in the domestication process. The data indicates that rengarenga was brought into cultivation independently at least three times, with the sources of these introductions located within a narrow area encompassing about 250km of coastline. Hybridization was inferred between A. cirratum and the closely related A. bifurcatum, despite A. birfucatum not occurring in the vicinity.

1. Guarded hot plate technique was used to measure thermal conductance of winter, summer and sheared pelts of Lama guanicoe. 2. Mean thermal conductance of winter and summer pelage was 1.64 W/m2 °C and 1.79 W/m2 °C, respectively. 3. Mean heat loss in natural pelage, in free convection conditions was 1.74 W/m2 °C and 2.3 W/m2 °C in sheared pelts. 4. From our results, there is seasonal moult in guanacos.