Diversity — Open Access Journal

Roads exert multiple effects on wildlife, from animal mortality, habitat and population fragmentation, to modification of animal reproductive behaviour. Amphibians are the most frequently road-killed animal group. Many studies have attempted to analyse the factors driving amphibian casualties on roads, but these factors are limited to the roads themselves (e.g., traffic, type of roads, roads crossing water bodies) or to structures along them (e.g., ditches, walls). Sometimes, roadkills are related to land use along the roads. We analysed the influence of landscape factors on roadkill hotspots at the national level (Slovenia). Specifically, we aimed at: (1) identifying hotspots of roadkills, (2) analysing whether records of amphibian presence on roads are related to the distribution of water bodies and (3) analysing which factors (proximity to water bodies or human factors) explain the distribution of hotspots. Hotspots were identified by Malo’s method. Roadkills were modelled with Maxent for the first time in Slovenia. The relationships between amphibian presence and hotspots with factors were analysed with GLM. A total of 237 road sections were identified as hotspots, corresponding to 8% of road sections and containing 90% of road-killed individuals. Proximity to forests, meadows and agricultural land were the most important variables in Maxent models. The number of roadkills depended on the proximity to agricultural land, forests, water bodies and wetland areas, while the number of hotspots additionally depended on the proximity to urban settlements. Full article

Oscillations of periods with low and high temperatures during the Quaternary in the northern hemisphere have influenced the genetic composition of birds of the Palearctic. During the last glaciation, ending about 12,000 years ago, a wide area of the northern Palearctic was under lasting ice and, consequently, breeding sites for most bird species were not available. At the same time, a high diversity of habitats was accessible in the subtropical and tropical zones providing breeding grounds and refugia for birds. As a result of long-term climatic oscillations, the migration systems of birds developed. When populations of birds concentrated in refugia during ice ages, genetic differentiation and gene flow between populations from distinct areas was favored. In the present study, we explored the current genetic status of populations of the migratory European bee-eater. We included samples from the entire Palearctic-African distribution range and analyzed them via mitochondrial and nuclear DNA markers. DNA data indicated high genetic connectivity and panmixia between populations from Europe, Asia and Africa. Negative outcomes of Fu’s Fs and Tajima’s D tests point to recent expansion events of the European bee-eater. Speciation of Merops apiaster started during the Pliocene around three million years ago (Mya), with the establishment of haplotype lineages dated to the Middle Pleistocene period circa 0.7 Mya. M. apiaster, which breed in Southern Africa are not distinguished from their European counterparts, indicating a recent separation event. The diversification process of the European bee-eater was influenced by climatic variation during the late Tertiary and Quaternary. Bee-eaters must have repeatedly retracted to refugia in the Mediterranean and subtropical Africa and Asia during ice ages and expanded northwards during warm periods. These processes favored genetic differentiation and repeated lineage mixings, leading to a genetic panmixia, which we still observe today. Full article

Blue mussels (Mytilus edulis) are ecosystem engineers with strong effects on species diversity and abundances. Mussel beds appear to be declining in the Gulf of Maine, apparently due to climate change and predation by the invasive green crab, Carcinus maenas. As mussels die, they create a legacy of large expanses of shell biogenic structure. In Maine, USA, we used bottom traps to examine effects of four bottom cover types (i.e., live mussels, whole shells, fragmented shells, bare sediment) and wind condition (i.e., days with high, intermediate, and low values) on flow-related ecosystem processes. Significant differences in transport of sediment, meiofauna, and macrofauna were found among cover types and days, with no significant interaction between the two factors. Wind condition had positive effects on transport. Shell hash, especially fragmented shells, had negative effects, possibly because it acted as bed armor to reduce wind-generated erosion and resuspension. Copepods had the greatest mobility and shortest turnover times (0.15 d), followed by nematodes (1.96 d) and the macrofauna dominant, Tubificoides benedeni (2.35 d). Shell legacy effects may play an important role in soft-bottom system responses to wind-generated ecosystem processes, particularly in collapsed mussel beds, with implications for recolonization, connectivity, and the creation and maintenance of spatial pattern. Full article

Species distribution models (SDMs) are popular tools for predicting the geographic ranges of species. It is common practice to use georeferenced records obtained from online databases to generate these models. Using three species of Phaedranassa (Amaryllidaceae) from the Northern Andes, we compare the geographic ranges as predicted by SDMs based on online records (after standard data cleaning) with SDMs of these records confirmed through extensive field searches. We also review the identification of herbarium collections. The species’ ranges generated with corroborated field records did not agree with the species’ ranges based on the online data. Specifically, geographic ranges based on online data were significantly inflated and had significantly different and wider elevational extents compared to the ranges based on verified field records. Our results suggest that to generate accurate predictions of species’ ranges, occurrence records need to be carefully evaluated with (1) appropriate filters (e.g., altitude range, ecosystem); (2) taxonomic monographs and/or specialist corroboration; and (3) validation through field searches. This study points out the implications of generating SDMs produced with unverified online records to guide species-specific conservation strategies since inaccurate range predictions can have important consequences when estimating species’ extinction risks. Full article

During the day, hummingbirds quickly metabolize floral nectar to fuel high metabolic demands, but are unable to feed at night. Though stored fat is the primary nocturnal metabolic fuel, it has been suggested that hummingbirds store nectar in their crop to offset fat expenditure in the night or to directly fuel their first foraging trip in the morning. We examine the use of crop-stored sugar in the nocturnal energy budget of ruby-throated hummingbirds (Archilochus colubris) using respirometry and ¹³C stable isotope analysis. Hummingbirds were fed a ¹³C-enriched sugar solution before lights-out and held in respirometry chambers overnight without food. Respirometry results indicate that the hummingbirds metabolized the sugar in the evening meal in less than 2 h, and subsequently primarily catabolized fat. Breath stable isotope signatures provide the key insight that the hummingbirds converted a substantial portion of an evening meal to fats, which they later catabolized to support their overnight metabolism and spare endogenous energy stores. These results show that the value of a hummingbird’s evening meal depends on how much of this energy was converted to fat. Furthermore, this suggests that evening hyperphagia is an important energy maximization strategy, especially during energetically expensive periods such as migration or incubation. Full article

The measurement of stable isotopes in ‘bulk’ animal and plant tissues (e.g., muscle or leaf) has become an important tool for studies of functional diversity from organismal to continental scales. In consumers, isotope values reflect their diet, trophic position, physiological state, and geographic location. However, interpretation of bulk tissue isotope values can be confounded by variation in primary producer baseline values and by overlapping values among potential food items. To resolve these issues, biologists increasingly use compound-specific isotope analysis (CSIA), in which the isotope values of monomers that constitute a macromolecule (e.g., amino acids in protein) are measured. In this review, we provide the theoretical underpinnings for CSIA, summarize its methodology and recent applications, and identify future research directions. The key principle is that some monomers are reliably routed directly from the diet into animal tissue, whereas others are biochemically transformed during assimilation. As a result, CSIA of consumer tissue simultaneously provides information about an animal’s nutrient sources (e.g., food items or contributions from gut microbes) and its physiology (e.g., nitrogen excretion mode). In combination, these data clarify many of the confounding issues in bulk analysis and enable novel precision for tracing nutrient and energy flow within and among organisms and ecosystems. Full article

Ecosystem engineers that serve as foundation species shape the ecology and behavior of the species which depend on them. As species shift their geographic ranges into ecosystems they have not previously inhabited, it is important to understand how interactions with novel foundation species alter their behavior. By employing behavioral assays and morphological analyses, we examined how individual morphology and foundation species structure impact the ritualistic aggression behavior of the range shifting mangrove tree crab Aratus pisonii between its historic and colonized habitats. Structure of the foundation species of the colonized salt marsh ecosystem increases the incidence and risk of this behavior over the historic mangrove habitat, potentially negating benefits of ritualizing aggression. Further, docks within the salt marsh, which are structurally analogous to mangroves, mitigate some, but not all, of the increased costs of performing ritualized aggression. Crabs in the salt marsh also had relatively larger claws than conspecifics from the dock and mangrove habitats, which has implications for the risk and outcomes of ritualized interactions. These changes to morphology and behavior highlight the impacts that foundation species structure can have on the morphology, ecology, and behavior of organisms and the importance of studying these impacts in range shifting species. Full article

Invasive alien species are widespread in freshwater systems compared to terrestrial ecosystems. Among crustaceans, crayfish in particular have been widely introduced and are considered a major threat to freshwater ecosystem functioning. New emerging techniques for detecting and controlling invasive crayfish and protecting endangered native species are; thus, now highly desirable and several are under evaluation. Important innovations have been developed in recent years for detection of both invasive and native crayfish, mainly through eDNA, which allows for the detection of the target species even at low abundance levels and when not directly observable. Forecasting models have also moved towards the creation of realistic invasion scenarios, allowing effective management plans to be developed in advance of invasions. The importance of monitoring the spread and impacts of crayfish and pathogens in developing national data and research networks is emphasised; here “citizen science” can also play a role. Emerging techniques are still being considered in the field of invasive crayfish control. Although for decades the main traditional techniques to manage invasive crayfish were solely based on trapping, since 2010 biological, biocidal, autocidal controls and sexual attractants, monosex populations, RNA interference, the sterile male release technique and oral delivery have all also been investigated for crayfish control. In this review, ongoing methodologies applied to the detection and management of invasive crayfish are discussed, highlighting their benefits and limitations. Full article

This study provides an illustrated synoptic key and comparative morphology to the 38 known larvae of dryophthorine genera representing seven subtribes in four of the five tribes: Cactophagus LeConte, Cosmopolites Chevrolat, Cyrtotrachelus Schoenherr, Diathetes Pascoe, Diocalandra Faust, Dryophthoroides Roelofs, Dryophthorus Germar, Dynamis Chevrolat, Eucalandra Faust, Eugnoristus Schoenherr, Foveolus Vaurie, Mesocordylus Lacordaire, Metamasius Horn, Metamasius (=Paramasius Kuschel), Myocalandra Faust, Nassophasis Waterhouse, Nephius Pascoe, Odoiporus Chevrolat, Phacecorynes Schoenherr, Polytus Faust, Poteriophorus Schoenherr, Rhabdoscelus Marshall, Rhinostomus Rafinesque, Rhodobaenus LeConte, Rhynchophorus Herbst, Scyphophorus Schoenherr, Sipalinus Marshall, Sitophilus Schoenherr, Sparganobasis Marshall, Sphenophorus Schoenherr, Stenommatus Wollaston, Temnoschoita Chevrolat, Trigonotarsus Guerin-Meneville, Trochorhopalus Kirsch, Tryphetus Faust, Xerodermus Lacordaire, and Yuccaborus LeConte. Only Prodioctes Pascoe was not included due to lack of specimens to examine. Seven genera are reported here for the first time. Detailed line drawings of the mouthparts of 37 genera are provided. The synoptic key is a multi-entry key, different from a traditional, single entry dichotomous key, which allows the user to identify dryophthorine larvae using any combination of characters (couplets). A total of 52 characters are included. This study provides support for the retention of Stromboscerini in the subfamily. Full article

Non-native crayfish invasion is a major threat to many stream fauna; however, invasions in subterranean habitats are rarely documented. Our study objectives were to examine demographics and morphological and life-history traits of a gapped ringed crayfish Faxonius neglectus chaenodactylus population that invaded Tumbling Creek Cave and determine the effects of removal on the population. Crayfish were found throughout the cave though fewer individuals were observed upstream of an installed weir. Fecund females were collected in nearly all months, but were prevalent during spring (February–June). Males and females were of similar sizes. Males had larger chelae and chelae that were regenerated slightly more often than females. Removal of >4000 crayfish since 2011 resulted in reduced abundances, but the population persisted. Age estimates from counting bands on gastric mills indicated crayfish within the cave lived longer than populations in nearby Big Creek (6 vs. 4 years). Recent efforts to prevent upstream cave migrations included a barrier installation and since installation, few crayfish have been located upstream. We show that exploitation of new environments may lead to trait changes (i.e., reproduction and longevity). We also demonstrate that barriers reduce the spread of invasion at a comparable cost to removal. We hypothesize that increased reservoir elevation inundates springs hydrologically connected to the cave and this may be the invasion source. Full article

Lingulids and discinids are the only brachiopods that exhibit life histories that include a feeding planktonic stage usually referred to as a “larva”. We collected planktotrophic brachiopod larvae from the Pacific and Caribbean coasts of Panama and took a DNA barcoding approach with mitochondrial cytochrome c oxidase subunit I (COI), mitochondrial ribosomal 16S, and nuclear ribosomal 18S genes to identify those larvae and to estimate their diversity in the region. We observed specimens from both coasts with distinct morphologies typical of lingulid and discinid larvae. COI and 16S were sequenced successfully for the lingulid larvae but failed consistently for all discinid larvae. 18S was sequenced successfully for larvae from both families. Sequence data from each gene revealed one lingulid operational taxonomic unit (OTU) from Bocas del Toro on the Caribbean coast, and one lingulid OTU from the Bay of Panama on the Pacific coast. These OTUs differed by >20% for COI, >10% for 16S and ~0.5% for 18S. Both OTUs clustered with GenBank sequences of Glottidia species, the only genus of lingulids in the Americas, but were distinct from G. pyramidata the only species reported for the Caribbean. Analysis of 18S sequence data for discinid larvae recovered 2 OTUs, one exclusively from the Pacific and one with a mixture of Pacific and Caribbean larvae. The 18S marker does not provide enough resolution to distinguish between species, and comparisons with GenBank sequences suggest that one OTU includes Pelagodiscus species, while the other may include Discradisca species. When compared with other marine invertebrates, our surveys of brachiopod larvae through DNA barcoding show relatively low levels of diversity for Panama. Full article

Only a few weevils have been described from Burmese amber, and although most have been misclassified, they show unusual and specialised characters unknown in extant weevils. In this paper, we present the results of a study of a much larger and more diverse selection of Burmese amber weevils. We prepared all amber blocks to maximise visibility of structures and examined these with high-magnification light microscopy as well as CT scanning (selected specimens). We redescribe most previously described taxa and describe 52 new species in 26 new genera, accompanied by photographs. We compare critical characters of these weevils with those of extant taxa and outline the effects of distortion on their preservation and interpretation. We conclude that only two weevil families are thus far represented in Burmese amber, Nemonychidae and a newly recognised family, Mesophyletidae, which appears closely related to Attelabidae but cannot be accommodated in this family. The geniculate antennae and long rostrum with exodont mandibles of most Mesophyletidae indicate that they were highly specialised phytophages of early angiosperms preserved in the amber, likely ovipositing in flowers or seeds. This weevil fauna appears to represent an extinct mid-Cretaceous ecosystem and fills a critical gap in the fossil record of weevils. Full article

North American Speyeria butterflies are a group of conservation concern and a challenge to butterfly systematists. Establishing species delimitation and evolutionary relationships among Speyeria has proven difficult due to the polytypic nature of many species, coupled with the similarity of wing patterns of sympatric species. Recent molecular work has found not all Speyeria species to be monophyletic, which could be explained by improper species definitions, incomplete lineage sorting, or ongoing hybridization and introgression. However, these studies involved broad geographic sampling where molecular markers such as the DNA barcode may be especially subject to incomplete lineage sorting. Here we focus on a more local scale, analyzing the mitochondrial gene cytochrome oxidase subunit I (CoI) to test whether this marker recovers four sympatric Speyeria species: adiaste (W. H. Edwards, 1864), callippe (Boisduval, 1852), coronis (Behr, 1864), and zerene (Boisduval, 1852), in the greater San Francisco Bay Area. We found that CoI works well to separate all four species. Subspecies were less well-defined, with the S. adiaste subspecies clustering separately, but more mixed for the S. zerene and S. callippe subspecies. Overall, our analyses illustrate the utility of the DNA barcode for separating the Speyeria species and suggest further studies to investigate different geographic scales in order to elucidate genetic diversity patterns in this genus in North America. Full article

The Guiana Shield of South America contains savannas within one of the largest contiguous expanses of pristine tropical rainforest remaining in the world, but biodiversity in the grasslands is poorly known. In lowland Neotropical areas, bats typically comprise the most species-rich group of mammals. We compare the bat faunal community and phylogeography in the savanna habitats of the Llanos in Venezuela, Rupununi in Guyana, and Sipaliwini in Suriname. Measures of species diversity and relative abundance from standardized field survey methodology enable comparison among these three grassland regions. Genetic variation is summarized by DNA barcoding to examine biogeographic patterns across larger forest–savanna landscapes. A total of 76 species of bats is documented, of which 18 species are reported from all 3 savannas and 30 species are reported from only 1 of the savannas. Endemism is low with 5 taxa restricted primarily to dry, open habitats. However, 7 other species have divergent phylogeographic lineages associated with savanna populations. Although bat species are usually distributed over wide regions of the Neotropics, the habitat mosaics of the Guiana Shield have different faunal assemblages. Going back into the Miocene, the contractions and expansions of forest–savanna paleoenvironments over time have contributed to speciation and the current high levels of biodiversity in South America. Full article

Invasive alien species (IAS) are considered one of the major threats to biodiversity worldwide, thus requiring severe control strategies. Based on the promising results obtained in the field of insect pest management with polyvinyl chloride (PVC) for long-lasting release of attractants, the main aim of this study was to ascertain the efficacy of PVC/attractant dispensers also in the aquatic environment. Therefore, we developed PVC/food dispensers and evaluated their attractiveness, by means of behavioural bioassays on whole animals, over a 60-day period of continuous use towards the red swamp crayfish Procambarus clarkii, one of the top 100 worst IAS. The attractiveness in PVC of trehalose, leucine and taurocholic acid was also tested. Our results show that the PVC dispensers release the food and are strongly attractive for crayfish over a prolonged time, even if their effectiveness depends on the storage conditions: From 18 days when stored underwater at 23 °C up to 50 days when stored out of the water at −20 °C. Besides, trehalose, leucine and taurocholic acid in PVC resulted in reliable attractants for P. clarkii. The development of PVC dispensers for long-lasting release of attractants may help improve the efficiency of mass trapping strategies in the management and control of invasive crayfish. Full article

Bunaken National Park has been surveyed for a fourth time in 14 years, in an attempt to establish the species composition of heterobranch sea slugs in a baseline study for monitoring programs and protection of this special park. These molluscs are potentially good indicators of the health of an ecosystem, as many are species-specific predators on a huge variety of marine benthic and sessile invertebrates from almost every taxonomic group. Additionally, they are known to contain bio-compounds of significance in the pharmaceutical industry. It is therefore of paramount importance not only to document the species composition from a zoogeographic point of view, but to assist in their protection for the future, both in terms of economics and aesthetics. These four surveys have documented more than 200 species, with an approximate 50% of each collection found only on that survey and not re-collected. Many species new to science have also been documented, highlighting the lack of knowledge in this field. Full article

Cherax destructor is a crayfish endemic to south-eastern Australia and one of the last alien crayfish to be introduced in Italy. In the Laghi di Ninfa Natural Reserve (Latium region, Central Italy), the species was probably introduced in 1999, but only reported for the first time in 2008. Nearby this area, the most widespread alien crayfish is the red swamp crayfish Procambarus clarkii. In the Natural Reserve, between 2008 and 2013 and during spring and summer, crayfish sampling was carried out with baited traps to assess the distribution of C. destructor and its possible relationship with P. clarkii. Cherax destructor was first recorded in 2008; few P. clarkii were detected in the cultivation ponds where C. destructor was present in 2012 and 2013. Moreover, crayfish plague analyses evidenced a positive result in two out of the 12 sampled P. clarkii. Cherax destructor is now completely absent from the Natural Reserve, while P. clarkii has spread in the area and was probably responsible for this eradication since C. destructor is vulnerable to crayfish plague which was also detected in the area. An ecosystem restoration project in the area favoured the spread of. P. clarkii; the implications of this intervention are discussed. Full article

Global assessments of seagrass declines have documented accelerating rates of loss due to anthropogenic sediment and nutrient loadings, resulting in poor water quality. More recently, global temperature increases have emerged as additional major stressors. Seagrass changes in the Chesapeake Bay, USA provide important examples of not only the effects of human disturbance and climate forcing on seagrass loss, but also meadow recovery and resiliency. In the York River sub-tributary of the Chesapeake Bay, the meadows have been monitored intensively using annual aerial imagery, monthly transect surveys, and continuous water quality measurements. Here, Zostera marina has been demonstrating a shift in its historical growth patterns, with its biomass peaking earlier in the growing season and summer declines beginning earlier. We found an increasing trend in the length of the most stressful high temperature summer period, increasing by 22 days since 1950. Over the past 20 years, Z. marina’s abundance has exhibited periods of decline followed by recovery, with recovery years associated with greater spring water clarity and less time spent at water temperatures > 28 °C. Although human disturbance and climatic factors have been altering these seagrass meadows, resilience has been evident by an increase in reproductive output and regrowth from Z. marina seedlings following declines, as well as expansions of Ruppia maritima into areas previously dominated by Z. marina.Full article