Amanda M. Hale

Intraspecific Inversions Pose a Challenge for the trnH-psbA Plant DNA Barcode

Background The chloroplast trnH-psbA spacer region has been proposed as a prime candidate for use in DNA barcoding of plants because of its high substitution rate. However, frequent inversions associated with palindromic sequences within this region have been found in multiple lineages of Angiosperms and may complicate its use as a barcode, especially if they occur within species. Methodology/Principal Findings Here, we evaluate the implications of intraspecific inversions in the trnH-psbA region for DNA barcoding efforts. We report polymorphic inversions within six species of Gentianaceae, all narrowly circumscribed morphologically: Gentiana algida, Gentiana fremontii, Gentianopsis crinita, Gentianopsis thermalis, Gentianopsis macrantha and Frasera speciosa. We analyze these sequences together with those from 15 other species of Gentianaceae and show that typical simple methods of sequence alignment can lead to misassignment of conspecifics and incorrect assessment of relationships. Conclusions/Significance Frequent inversions in the trnH-psbA region, if not recognized and aligned appropriately, may lead to large overestimates of the number of substitution events separating closely related lineages and to uniting more distantly related taxa that share the same form of the inversion. Thus, alignment of the trnH-psbA spacer region will need careful attention if it is used as a marker for DNA barcoding.

TERRITORIALITY AND NEIGHBOR ASSESSMENT IN BROWN JAYS (CYANOCORAX MORIO) IN COSTA RICA

Abstract Defense of group-held resources is a common and widely accepted function of territorial interactions between neighboring groups. In addition, territorial interactions could provide opportunities to assess members of neighboring groups and reproductive opportunities there, or to solidify status in the home group. We studied group-level characteristics and individual participation in territorial encounters in the cooperatively breeding Brown Jay (Cyanocorax morio). Intergroup encounters at stable territory boundaries include both aggressive and affiliative behavior, which suggests that a territorial encounter could function as both a resource defense mechanism and as an arena for social interactions. Territory characteristics that increase the probability of contact between groups (long boundaries, large combined group size, and home range overlap) explain much of the variation in frequency of territorial encounters. Male-biased dispersal was more common to neighboring groups with long boundaries, supporting the idea that frequent interactions between neighbors facilitate dispersal. Females usually inherit breeding positions on their natal territories, and participation in intergroup encounters by females does not vary with age or breeding status. In addition to defending group resources, females on their natal territories could be defending their positions in the breeding queue. Immigrant females are not likely to breed successfully, or to disperse again, and they participated less than expected. Participation by both natal and immigrant males varied by age; young males, at the ages when dispersal and intergroup forays are most likely, participated more than expected, whereas older males (≥4 years) participated less. That is consistent with the hypothesis that participation in intergroup encounters facilitates dispersal and improves integration into social groups. Because extragroup matings occur in this population, both breeding females and males could be assessing neighboring individuals for mating opportunities. Resource defense and social facilitation are not mutually exclusive hypotheses, and our observations suggest that both are important components of territorial encounters in Brown Jays.

HELPER EFFECTS ON OFFSPRING PRODUCTION IN COOPERATIVELY BREEDING BROWN JAYS (CYANOCORAX MORIO)

Abstract Most studies of cooperatively breeding species have revealed that indirect fitness gains from helping are lower than benefits gained from direct reproduction. Exceptions to this “best of a bad job” strategy are rare. Brown Jays (Cyanocorax morio) in Monteverde, Costa Rica, live in large groups (mean = 10 individuals) and have never been observed to breed as unaided pairs. Helpers provide a substantial percentage (70%) of all nestling feedings. Together, these observations suggest that helping may be crucial for reproductive success in this population. We used multivariate models to examine the effect of helpers on offspring production using a long-term data set. Data on nest-site success and brood reduction suggested that predation was the major cause of nesting failure. Nesting in an isolated tree was the major determinant of successful nestling production, and our data indicate that small groups (less than 9 individuals) may not be able to acquire or defend territories that contain suitable nesting sites. The number of juveniles (young surviving 30 days after leaving the nest) and yearlings was positively related to group size, even after removing groups that nested only in non-isolated trees. Small groups were also more likely than large groups to have total reproductive failure in a season. Helpers may increase juvenile survival by reducing predation, increasing juvenile condition, or providing learning opportunities for foraging and antipredator behaviors. Helpers on their natal territories receive some indirect benefits, though these are low compared with independent breeding. Immigrant male helpers may benefit primarily by gaining future breeding opportunities. Delayed benefits related to territory inheritance and dispersal coalitions may be the best explanation for helping in this population. Efectos de los Ayudantes sobre la Producción de Progenie en Cyanocorax morio, una Especie con Cría Cooperativa

Advances in sex determination in bats and its utility in wind-wildlife studies.

We developed a simple and reliable genetic method to determine sex in bats from the Vespertilionidae and Molossidae families. Polymerase chain reaction was used to amplify a portion of the introns within the zinc‐finger‐X (Zfx) and zinc‐finger‐Y (Zfy) genes. We designed primers to produce size variation between the Zfx and Zfy products that could be visualized using gel electrophoresis. Using an example from our wind‐wildlife research, we show how sex data generated using this method are superior to sex data based on external morphology. Our method allows for the generation of sex data across a wide range of bats that can be used to address key questions in wildlife forensics, behavioural ecology, conservation and evolutionary biology.

Wind Turbines do not Negatively Affect Nest Success in the Dickcissel (Spiza americana)

ABSTRACT. Proliferation of wind energy across the Great Plains of the United States has the potential to negatively affect many grassland birds through displacement, avoidance, or changes in nesting ecology. This is troublesome because grassland birds have had the highest average annual rate of decline over the past several decades. We studied the potential indirect effects of wind turbines on nesting success in Dickcissels (Spiza americana) at a utility-scale wind farm in north-central Texas in 2010 and 2011. We monitored 195 nests and found that proximity to a wind turbine did not affect nest density or nest-site characteristics. We used an information-theoretic approach with logistic exposure modeling to identify the most likely models of nest fate. Nest initiation day and distance to wind turbine were the most important predictors of nest success. Proximity to a wind turbine did not reduce nest success. Furthermore, the daily survival rates at our site were within the range documented for Dickcissels at other sites without wind-energy developments. For the monitored nests, snake predation was the greatest source of nest failure and depredated nests were closer to woodland edges than to wind turbines. This may be because wind turbines were farther away from wooded edges. On the other hand, we cannot rule out the possibility that wind-energy development influenced predator behavior and activity, and this may warrant additional investigation. We recommend further research into the breeding ecology of a diverse selection of grassland species to fully assess the indirect effects of wind-energy development on grassland birds.

No evidence of displacement due to wind turbines in breeding grassland songbirds

ABSTRACT Projected global growth in wind energy development has the potential to negatively affect wildlife populations, and yet the indirect effects of wind turbines on wildlife (e.g., displacement from otherwise suitable habitat) remain largely understudied, compared with investigations of direct effects (e.g., collision mortality). Thus, over a 3-yr period (2009–2011), we used 2 alternative survey methods to study displacement in breeding grassland songbirds at an operational wind facility in the southern Great Plains, USA. Using a line transect method in 2009 and 2010, we estimated the densities of Dickcissels (Spiza americana), Eastern Meadowlarks (Sturnella magna), and Grasshopper Sparrows (Ammodramus savannarum) within 500 m of wind turbines. Dickcissel density was positively related to vegetation structure and was highest 301–400 m from wind turbines in both years; however, this relationship was confounded by fence lines bisecting transects within this single distance bin. By contrast, we found no such relationships in Eastern Meadowlarks or Grasshopper Sparrows. Using a plot-based method in 2011, we estimated Dickcissel and Grasshopper Sparrow densities within 750 m of wind turbines. Again, we found a strong positive relationship between Dickcissel density and vegetation structure. With the change in survey method, however, the confounding effect of fence lines was removed and the relationship between distance to turbine and Dickcissel density disappeared. Variation in Grasshopper Sparrow density in 2011 was not explained by any variable we measured. In summary, we found no evidence of displacement within 500–750 m of wind turbines in the 3 most abundant breeding grassland songbirds at our site. We caution that it may be difficult to isolate the effect of distance to turbine from other factors that covary with distance (e.g., presence of fence lines) when using a line transect method to study displacement at operational wind facilities.

Mercury contamination in bats from the central United States

Mercury (Hg) is a highly toxic metal that has detrimental effects on wildlife. We surveyed Hg concentrations in 10 species of bats collected at wind farms in the central United States and found contamination in all species. Mercury concentration in fur was highly variable both within and between species (range: 1.08-10.52 µg/g). Despite the distance between sites (up to 1200 km), only 2 of the 5 species sampled at multiple locations had fur Hg concentrations that differed between sites. Mercury concentrations observed in the present study all fell within the previously reported ranges for bats collected from the northeastern United States and Canada, although many of the bats we sampled had lower maximum Hg concentrations. Juvenile bats had lower concentrations of Hg in fur compared with adult bats, and we found no significant effect of sex on Hg concentrations in fur. For a subset of 2 species, we also measured Hg concentration in muscle tissue; concentrations were much higher in fur than in muscle, and Hg concentrations in the 2 tissue types were weakly correlated. Abundant wind farms and ongoing postconstruction fatality surveys offer an underutilized opportunity to obtain tissue samples that can be used to assess Hg contamination in bats. Environ Toxicol Chem 2018;37:160-165.

Investment in Nesting Activities and Patterns of Extra- and Within-Group Genetic Paternity in a Cooperatively Breeding Bird

Abstract Individuals are predicted to direct aid-giving behaviors preferentially to kin. In this study, we examined patterns of investment in nesting activities and compared them to genetic paternity across a three-year period (1994–1996) in cooperatively breeding Brown Jays (Cyanocorax morio) in Monteverde, Costa Rica. Brown Jays live in large, territorial groups (mean = 10 individuals) that usually contain a single primary nesting female, her social mate (consort), and helpers of both sexes. Consorts were identified in most but not all nesting female-years; the consort–breeding female relationship was a stable one that often persisted across years, and consorts spent more time with the breeding females than did any other group males during nest building and egg laying. At an individual level, helpers invested little time in the nest area or feeding effort during the prenestling stages, although they provided the majority of feedings (90%) to the breeding female. The breeding pair spent more time in the nest area and had higher nestling feeding rates than the helpers. Consorts did not reduce their investment in nestling feeding in cases where they had not obtained paternity. Within-group extra-pair fathers, on the other hand, tended to provision nestlings less than did other nonbreeding males and were very rarely seen in the nesting areas. Extra-group fathers provided no nestling care. Brown Jay consorts appear to invest less in nesting activities compared to other well-studied New World jays. These findings suggest that mate guarding may be ineffective for consorts, and that both consorts and helper males may invest little in nesting activities because they are pursing mating or dispersal opportunities outside their social groups.

NESTING SUCCESS OF SCISSOR-TAILED FLYCATCHERS (TYRANNUS FORFICATUS) AT A WIND FARM IN NORTHERN TEXAS

Abstract We investigated indirect effects of wind turbines on nesting success of scissor-tailed flycatchers (Tyrannus forficatus). We tracked the fate of 32 nests at Wolf Ridge Wind, LLC, Cooke County, Texas, during the breeding season in 2009. Overall rates of predation on nests were high, reproductive success was low, daily rates of survival were only 93.5%, only 16% of nests fledged ≥1 offspring, and nests had only a 13.3% chance of survival from initiation to fledging. Amount of canopy cover and distance to nearest turbine best predicted success or failure of nests; nests with less canopy cover that were closer to a wind turbine had a higher daily rate of survival than nests with more canopy cover farther away. Less canopy cover might be associated with fewer terrestrial or arboreal predators on nests, while proximity to turbines might reduce aerial predation on nests. Resumen Investigamos los efectos indirectos de las turbinas de viento en el éxito reproductivo del papamoscas tijereta (Tyrannus forficatus). Rastreamos los fines de 32 nidos en Wolf Ridge Wind, LLC, condado de Cooke, Texas, durante la temporada reproductiva del 2009. Las tasas de depredación de nidos en general fueron altas y el éxito reproductivo fue bajo, con las tasas de sobrevivencia por día de sólo 93.5%, sólo 16% de los nidos produjeron ≥1 crías, y los nidos tuvieron una oportunidad de sobrevivir desde el inicio del nido hasta la salida de los volantones de sólo 13.3%. La cantidad de la cobertura del dosel y la distancia a la turbina más próxima predijeron mejor el éxito o el fracaso del nido; nidos con menos cobertura del dosel y más cerca a la turbina más próxima tuvieron una tasa de sobrevivencia por día más alta que los que construyeron más lejos y con más cobertura del dosel. Menos cobertura del dosel puede estar asociada con menos depredadores terrestres o arbóreos del nido, mientras que la proximidad a la turbina puede reducir la frecuencia de los depredadores aéreos del nido.

The Phylogeny of Ayenia , Byttneria, and Rayleya (Malvaceae s. l.) and its Implications for the Evolution of Growth Forms

Abstract Tropical plants show a diversity of growth forms, yet few phylogenies are available to examine the transitions between trees, shrubs, and lianas. Here, we reconstruct relationships among 37 species of Ayenia, Byttneria, and Rayleya with cpDNA sequences, and use the resulting phylogeny to test hypotheses on the evolution of climbing plants and to examine biogeography of these plants. Results show that Rayleya is sister to a combined clade of Ayenia and Byttneria; Byttneria is paraphyletic with Ayenia nested within it. The common ancestor of the combined Ayenia/Byttneria/Rayleya clade is reconstructed as a neotropical tree or shrub. Within the Ayenia/Byttneria clade, there is a single transition to unarmed lianas, with subsequent radiations into the Asian and African tropics. A second independent transition from trees or shrubs to spiny, semi-scandent shrubs occurred in the neotropics. We found no evidence of transitions from lianas to any other growth form; however, we recovered a reversal from semi-scandent shrubs to fully upright plants. Within the neotropics, there are two independent radiations into seasonal, open habitats. Additional sampling of African species of Byttneria may yield more complicated scenarios in both biogeography and the evolution of growth forms.