Giant petrels as predators of albatross chicks

Giant petrels Macronectes spp. are not thought to be important predators of albatross chicks, although they are known to kill pre-fledging Thalassarche and Phoebetria albatrosses. We report the first records of predation of healthy great albatross Diomedea spp. chicks, killing wandering albatrosses D. exulans at night on sub-Antarctic Marion Island. Breeding success of this species has decreased markedly in the area where attacks occurred, suggesting that giant petrel predation events are a recent phenomenon. Mouse attacks on wandering albatross chicks may have contributed to the development of this hunting technique. We also report the first observations of giant petrel predation on pre-fledging grey-headed albatross T. chrysostoma chicks as well as additional records of sooty albatross P. fusca chicks being targeted. Only adult northern giant petrels M. halli have been confirmed to kill albatross chicks on Marion Island. Given the threatened status of wandering albatrosses, and the importance of Marion Island for this species, monitoring of their breeding success is necessary to assess whether the predation of chicks by giant petrels spreads around the island.     

Loopholes in the regulation of invasive species: genetic identifications identify mislabeling of prohibited aquarium plants

Numerous invasive aquatic species introductions can be traced to the aquarium trade. Many potentially harmful aquarium species may be difficult to identify based on morphology alone. As such, some prohibited or invasive species may be available for purchase if they are mislabeled as species without restrictions. Here we compare molecular identifications to internet vendors’ identifications for accessions of a popular genus of aquarium plants that are difficult to distinguish morphologically (Myriophyllum; watermilfoils). Specifically, we identified the extensive mislabeling of M. heterophyllum—an invasive species in the northeastern and western US. Furthermore, genotypes of M. heterophyllum found in our aquarium survey have also been found in invasive populations, suggesting their potential introduction through escape from aquaria, water gardens, or nurseries. Two additional taxa were sold under incorrect names. Finally, our survey revealed that Myriophyllum taxa present in the aquarium trade generally have poorly known distributions and ecologies, and therefore their invasive potential is unknown. Our study confirms that molecular identification methods can provide a valuable tool to survey commercial pathways for potentially harmful species that are otherwise difficult to identify.     

Validity Analysis of the Morphological Identification of Three Highly Morphologically Similar Species Belonging to the Genus Niviventer (Rodentia: Muridae)

Cryptic species are prevalent among mammals, and identifying morphological methods or measurements that can effectively distinguish cryptic species has high significance in taxonomy. Three of the white-bellied rats, Niviventer confucianus, N. fulvescens and N. huang (Rodentia: Muridae), have such similar morphological characteristics that taxonomists have not been able to effectively identify them according to their morphologies. Recent studies have determined that the N. fulvescens species complex contains multiple species, indicating that previous morphological comparisons were potentially based on inaccurate species identifications, leading to false conclusions. To clarify whether the morphological differences among these three species can be used for identification, a variety of morphological methods and measurements were combined with molecular species identification to ensure accurate identifications prior to comparing morphological characteristics. The results showed that: (1) only N. confucianus has a white tail tip, distinguishing this species from the other two species but not N. fulvescens from N. huang; and (2) the tail length of N. fulvescens and ear length of N. confucianus are greater than those of the other species. Traditional morphological methods cannot differentiate these species well, with the discrimination rate reaching more than 90%; therefore, they can only be used as auxiliary methods for morphological identification. Additionally: (3) the geometric morphological results of the four skull views can be combined to distinguish the three species, among which the discrimination rate of lateral view of mandible reaches 98%, making it effective for differentiating these species; and (4) the phallic morphologies of the three species differed significantly in the presence of a dorsal groove, thickness of the distal baculum, and the positional relationship between the distal and proximal baccula; thus, this approach can completely distinguish these species. This study examines the applicability of various morphological measurements for the identification of highly morphologically similar species, provides a reference for distinguishing cryptic species produced by convergent evolution or incomplete differentiation by morphology, and suggests that phallic morphology should be the primary characteristic for differentiating such species in the future.

     

Accumulation and toxicity assessment of polychlorinated biphenyls in black-footed albatross (Diomedea nigripes) from Midway Atoll,North Pacific Ocean

Polychlorinated biphenyls (PCBs) are ubiquitous chemicals that were used as additives in capacitors and transformers; and heavy contamination in the past of Midway Atoll, a national wildlife refuge, puts the wildlife, including the black-footed albatross (BFAL), at risk. In this study, we assess the profiles and toxicity of the individual PCB congeners at a natural equilibrium state in various tissues of 1-month old and 4–5-month old BFAL chicks and black-footed and Laysan albatross eggs found on the atoll. In the 1-month old chicks from Midway Atoll, the major seven congeners PCBs 99, 118, 138, 153, 170, 180 and 183 accounted for 36–78% of the total PCBs in the various body parts, and the total PCB concentrations in the bird samples are inversely related to the total body weights. In the 4–5-month old chicks, these same congeners accounted for much lower percentages (7–26%) than in the 1-month-old chicks, with higher amounts of the less chlorinated congeners. The total toxic equivalents (TEQs) for all of the tissues in the 1-month old chicks ranged from 130 to 11,000 pg g⁻¹ (lipid weight, lw), and the total TEQs for the 4–5-month old chicks ranged from 18,000 to 100,000 pg g⁻¹. The average total concentration was 7.9 and 4.6 μg g⁻¹ lw in the BFAL eggs and Laysan albatross eggs, respectively. The high concentrations could be accounted for by the age and PCB accumulation of the female producing the egg. The average TEQs were 70 and 90 pg g⁻¹ in the Laysan albatross eggs and BFAL eggs, respectively. This PCB concentration and toxicity information can be used to determine the toxicological risk of the BFAL chicks while nesting at Midway Atoll, and the analysis of the albatross eggs is an indication of the contamination of the female albatross at the time of egg formation, with the levels acting as an indicator of the total PCB body burdens that the females are experiencing. The information from this study is indicative of the toxicological risk to the seabirds that nest and feed near Midway and of the overall PCB contamination in the North Pacific Ocean.     

Morphometric and molecular identification of the female castes of Bombus ignitus and B. ardens (Apidae: Hymenoptera)

Among Korean bumblebees, Bombus ignitus and B. ardens are relatively abundant and important for pollination of wildflowers and agricultural crops. Although the males are easily distinguishable phenotypically, the female castes are difficult to identify from each other. Here we evaluated the value of some morphometric characters in species identification. Also, we developed a polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) to discriminate these similar species. In spite of statistically significant differences of some morphological characters between two species, overlapping quantitative traits hindered accurate identification of the species. However, using 435 bp of COI gene and AluI, BspHI and Earl restriction enzymes allowed molecular identifications of these two species with unique profiles from the digestion by these restriction enzymes. This method can also be applied for older specimens with some morphological characters damaged. We also developed species-specific primers for fast and cost-effective identification of these species.     

Development of internal COI primers to improve and extend barcoding of fruit flies (Diptera: Tephritidae: Dacini)

Accurate species-level identifications underpin many aspects of basic and applied biology;however,identifications can be hampered by a lack of discriminating morphological characters,taxonomic expertise or time.Molecular approaches,such as DNA"barcoding"of the cytochrome c oxidase(COI)gene,are argued to overcome these issues.However,nuclear encoding of mitochondrial genes(numts)and poor amplification success of suboptimally preserved specimens can lead to erroneous identifications.One insect group for which these molecular and morphological problems are significant are the dacine fruit flies(Diptera:Tephritidae:Dacini).We addressed these issues associated with COI barcoding in the dacines by first assessing several"universal"COI primers against public mitochondrial genome and numt sequences for dacine taxa.We then modified a set of four primers that more closely matched true dacine COI sequence and amplified two overlapping portions of the COI barcode region.Our new primers were tested alongside universal primers on a selection of dacine species,including both fresh preserved and decades-old dry specimens.Additionally,Bactrocera tiyoni mitochondrial and nuclear genomes were compared to identify putative numts.Four numt clades were identified,three of which were amplified using existing universal primers.In contrast,our new primers preferentially amplified the"true"mitochondrial COI barcode in all dacine species tested.The new primers also successfully amplified partial barcodes from dry specimens for which full length barcodes were unobtainable.Thus we recommend these new primers be incorporated into the suites of primers used by diagnosticians and quarantine labs for the accurate identification of dacine species.     

ORIGIN OF TRIPSACUM ANDERSONII (GRAMINEAE)

Tripsacum andersonii Gray (Gramineae) is a species with 2n = 64 chromosomes. Chromosome behaviour during meiosis of microsporogenesis suggests that the species combines three homologous haploid Tripsacum genomes of x = 18 (54 chromosomes), and an alien haploid genome of x = 10 chromosomes. Cytogenetic studies indicate that T. andersonii originated as a hybrid between a species of Tripsacum (2n = 36) and a species of Zea (2n = 20). Comparative morphology and flavonoid chemistry fail to identify the Zea species involved in this intergeneric hybrid. Chromosome morphology suggests that it was either Z. mays L. subsp. mays (domesticated maize) or subspecies mexicana (Schrad.) Iltis (annual teosinte). The Tripsacum parent probably was T. latifolium Hitchc. of Central America. It resembles T. andersonii in vegetative morphology. Tripsacum maizar Hernandez et Randolph and T. laxum Nash, which resemble T. andersonii in flavonoid chemistry, are eliminated as possible parents on the basis of growth habit and the morphology of their hybrids with maize.     

Single-step PCR differentiation of Cotesia sesamiae (Cameron) and Cotesia flavipes Cameron (Hymenoptera: Braconidae) using polydnavirus markers

Cotesia sesamiae (Cameron) and Cotesia flavipes Cameron (Hymenoptera: Braconidae) are the main larval parasitoids of cereal stemborers in sub-Saharan Africa. Cotesia sesamiae is endemic to eastern and southern Africa, while C. flavipes was introduced into the region for biological control against the exotic lepidopteran Chilo partellus (Swinhoe) (Lepidoptera: Crambidae). The two are sibling parasitoids, difficult to distinguish morphologically. The introduced insect could potentially lead its African biotype to extinction because of their similar ecological niche. In order to distinguish the two species, multiplex primer-specific and PCR-RFLP tests were developed. Rapid identification of the two species was possible using primer-specific tests on DNA extracts as well as on pieces of tissue in a single PCR step followed by gel electrophoresis. The CRV1 gene of the polydnavirus, a symbiont to the wasps, was used as the marker. The results show that the morphological identifications, validated by molecular tests, are accurate in 93% of cases.     

DNA barcoding of brown Parmeliae (Parmeliaceae) species: a molecular approach for accurate specimen identification,emphasizing species in Greenland

Warming of Arctic and alpine regions has a substantial impact on high-altitude/-latitude ecosystems. Shifting biomes due to climate change may lead to adjustments in species distributions and potential extinctions. Therefore, detailed monitoring is requisite to assess biologically meaningful shifts in community composition and species distributions. Some Arctic-alpine lichens have been shown to be particularly sensitive to climatic shifts associated with global change. However, accurate identification of lichenized fungal species remains challenging and may limit the effective use of lichens in climate change research. Given the inherent difficulties in accurate identification of lichenized fungi and the potential value of efficient identifications for bio-monitoring research, we investigated the utility of DNA barcode identification of the 13 brown Parmeliae (Ascomycota) species occurring in Greenland. For these species, we assessed monophyly and genetic distances using the nuclear ribosomal internal transcribed spacer region (ITS), the standard DNA barcode for fungi. We also compared intraspecific distance values to a proposed intra-interspecific threshold value for Parmeliaceae to identify nominal taxa potentially masking previously unrecognized diversity. Our results indicated that the 13 brown Parmeliae species occurring in Greenland can be successfully discriminated using the ITS region. All phenotypically circumscribed species were recovered as well-supported, monophyletic clades. Furthermore, our data supported a barcode gap among congeners for all brown Parmeliae species investigated here. However, high intraspecific genetic distances suggest the potential for previously unrecognized species-lineages in at least five species: Melanelia agnata, M. hepatizon, Montanelia disjuncta, M. panniformis, and M. tominii. Our research facilitates effective, long-term bio-monitoring of climate change in Greenland using lichens by providing accurate molecular identification of brown Parmeliae specimens.     

Food partitioning among three sympatric odontocetes (Grampus griseus,Lagenodelphis hosei,and Stenella attenuata)

Food is one of the most important dimensions of resource partitioning for species coexistence. In this study, we investigated the dietary composition and foraging habits of three sympatric odontocetes in order to identify their levels of food niche overlap and ecological separation. Stomach content analysis was performed on samples collected from carcasses confiscated by police or entangled in gill nets from 1994 to 2001, including 27 Risso's dolphins (GG) (Grampus griseus), 27 Fraser's dolphins (LH) (Lagenodelphis hosei), and 45 pantropical spotted dolphins (SA) (Stenella attenuata). GG consumed only cephalopods, with Enoploteuthis chunii accounting for 90.5% of total prey consumed, LH fed on mesopelagic fishes and cephalopods, dominated by hatchetfish, Polyipnus stereope (50.2%), and SA ate both mesopelagic and epipelagic preys, primarily fishes of Myctophum asperum (20.3%) and squids of E. chunii (25.8%). Among the three odontocetes, GG had the narrowest dietary niche width, while SA had the widest width. Both the niche overlap index and the analysis of similarities (ANOSIM) showed significant diet differentiation among these three dolphin species. The depth distribution of their principal prey items further suggests that LH feeds in the deepest waters while SA utilizes prey resources near surface.     

DNA barcoding of genus Toxoptera Koch (Hemiptera: Aphididae): Identification and molecular phylogeny inferred from mitochondrial COI sequences

Abstract Identification of aphid species is always difficult due to the shortage of easily distinguishable morphological characters. Aphid genus Toxoptera consists of species with similar morphology and similar to Aphis in most morphological characters except the stridulatory apparatus. DNA barcodes with 1 145 bp sequences of partial mitochondrial cytochrome‐coxidase I (COI) genes were used for accurate identification of Toxoptera. Results indicated mean intraspecific sequence divergences were 1.33%, whereas mean interspecific divergences were greater at 8.29% (0.13% and 7.79% if T. aurantii 3 and T. aurantii 4 are cryptic species). Sixteen samples were distinguished to four species correctly by COI barcodes, which implied that DNA barcoding was successful in discrimination of aphid species with similar morphology. Phylogenetic relationships among species of this genus were tested based on this portion of COI sequences. Four species of Toxoptera assembled a clade with low support in maximum‐parsimony (MP) analysis, maximum‐likelihood (ML) analysis and Bayesian phylogenetic trees, the genus Toxoptera was not monophyletic, and there were two sister groups, such as T. citricidus and T. victoriae, and two clades of T. aurantii which probably presented cryptic species in the genus.     

Breeding‐site vagrancy and hybridization in albatrosses

Given the rarity of hybridization in seabirds, which presumably relates to their very high philopatry, the degree of breeding‐site vagrancy should correspond with the incidence of mixed‐species pairing, although not necessarily with the production of hybrids if there are behavioural or genetic barriers to successful reproduction. Using molecular methods, we verified that two of the three chicks hatched by a vagrant male White‐capped Albatross Thalassarche steadi paired with a female Black‐browed Albatross Thalassarche melanophris at South Georgia were genuine hybrids (these chicks died before fledging, but a third chick – the result of an extra‐pair copulation – fledged successfully). In a wider review, we could find only five known or suspected mixed‐species pairs, and three different hybrids in albatrosses, mostly between closely related species. This appears to reflect behavioural barriers to hybridization in sympatric species and the low incidence of breeding‐site vagrancy (which mainly involves single individuals that invariably associate with the most phenotypically similar local taxon). Breeding‐site vagrancy is most frequent in the ‘shy‐albatross’ complex, which could explain why genetic divergence occurred more recently in this group than in other Thalassarche, and hence exploratory behaviour appears to be more important than numerical abundance or breeding distribution in driving colonization as well as hybridization processes in albatrosses.     

Morphometric and molecular differentiation of Phlebotomus (Phlebotomus) sandflies

The closely related sandfly species of the subgenus Phlebotomus namely, Phlebotomus papatasi (Scopoli, 1786), Phlebotomus duboscqi Neveu‐Lemair, 1906 and Phlebotomus bergeroti Parrot, 1934 (Diptera: Psychodidae), are major vectors of Leishmania major (Kinetoplastida: Trypanosomatidae), the causative agent of cutaneous leishmaniasis in the Old World. Although allopatric in most of their distribution, the three species exist sympatrically in many places in central and eastern Sudan. Males of the three species can be distinguished using morphological characters; however, females are much harder to identify, thus complicating epidemiological studies. We carried out a morphometric and a molecular study to determine reliable morphological features and develop a polymerase chain reaction (PCR) assay for distinguishing females of these species. Males and females from each species were collected from sites in Sudan, East Africa and from one site in Mali, West Africa. Males were analysed morphologically and 20 characters and 10 character ratios were used in a stepwise discriminant analysis. This led to the identification of four characters with high discriminant loading scores sufficient for accurate male species identification. Male DNA was then used for the development of a PCR‐based species diagnostic based on the second internal transcribed spacer (ITS2) of the ribosomal DNA. A set of four primers was developed to generate fragment sizes that are specific to each species and can reliably identify females as well as hybrid DNA. Both the morphometric and the molecular findings of this study have important applications for studies of the epidemiology of cutaneous leishmaniasis.     

Projected distributions of Southern Ocean albatrosses,petrels and fisheries as a consequence of climatic change

Given the major ongoing influence of environmental change on the oceans, there is a need to understand and predict the future distributions of marine species in order to plan appropriate mitigation to conserve vulnerable species and ecosystems. In this study we use tracking data from seven large seabird species of the Southern Ocean (black‐browed albatross Thalassarche melanophris, grey‐headed albatross T. chrysostoma, northern giant petrel Macronectes halli, southern giant petrel M. giganteus, Tristan albatross Diomedea dabbenena, wandering albatross D. exulans and white‐chinned petrel Procellaria aequinoctialis, and on fishing effort in two types of fisheries (characterised by low or high‐bycatch rates), to model the associations with environmental variables (bathymetry, chlorophyll‐a concentration, sea surface temperature and wind speed) through ensemble species distribution models. We then projected these distributions according to four climate change scenarios built by the Intergovernmental Panel for Climate Change for 2050 and 2100. The resulting projections were consistent across scenarios, indicating that there is a strong likelihood of poleward shifts in distribution of seabirds, and several range contractions (resulting from a shift in the northern, but no change in the southern limit of the range in four species). Current trends for southerly shifts in fisheries distributions are also set to continue under these climate change scenarios at least until 2100; some of these may reflect habitat loss for target species that are already over‐fished. It is of particular concern that a shift in the distribution of several highly threatened seabird species would increase their overlap with fisheries where there is a high‐bycatch risk. Under such scenarios, the associated shifts in distribution of seabirds and increases in bycatch risk will require much‐improved fisheries management in these sensitive areas to minimise impacts on populations in decline.     

Identification of gobies (Teleostei: Perciformes: Gobiidae) from the North and Baltic Seas combining morphological analysis and DNA barcoding

Gobies are difficult to identify, as they are very similar in appearance. Here, we identified (sub)adult specimens of 12 goby species from the North Sea and the Baltic Sea by carefully analysing meristic characters, coloration patterns, papillae row patterns and morphometric measurements. The results of the morphological identifications were congruent with those obtained with the analysis of COI DNA barcodes; sequences from morphological conspecific specimens were clustered together in clades with bootstrap values ≥ 99%. Mean intra‐ and interspecific distance (uncorrected p) was 0.37 and 18.97%, respectively. A gap between the maximum intraspecific distance and the distance to the nearest neighbour was apparent in every species and ranged from 2.35 to 16.11%. The Barcode Index Number (BIN) analysis performed on the Barcode of Life Data Systems (BOLD) web platform, assigned the DNA barcodes to 12 separate clusters corresponding to sequence‐ and morphology‐based identification. In 25% of the investigated species, the BIN clusters showed taxonomic discordances, as they contained sequences assigned to more than one species. This result demonstrates the importance of accurate morphological species identification at the beginning of the barcoding pipeline. © 2014 The Linnean Society of London     

Utility of GenBank and the Barcode of Life Data Systems (BOLD) for the identification of forensically important Diptera from Belgium and France

Fly larvae living on dead corpses can be used to estimate post-mortem intervals. The identification of these flies is decisive in forensic casework and can be facilitated by using DNA barcodes provided that a representative and comprehensive reference library of DNA barcodes is available.We constructed a local (Belgium and France) reference library of 85 sequences of the COI DNA barcode fragment (mitochondrial cytochrome c oxidase subunit I gene), from 16 fly species of forensic interest (Calliphoridae, Muscidae, Fanniidae). This library was then used to evaluate the ability of two public libraries (GenBank and the Barcode of Life Data Systems – BOLD) to identify specimens from Belgian and French forensic cases. The public libraries indeed allow a correct identification of most specimens. Yet, some of the identifications remain ambiguous and some forensically important fly species are not, or insufficiently, represented in the reference libraries. Several search options offered by GenBank and BOLD can be used to further improve the identifications obtained from both libraries using DNA barcodes.     

Identification of molecular markers for DNA barcoding in the Aphidiinae (Hym. Braconidae)

Reliable identification of Aphidiinae species (Braconidae) is a prerequisite for conducting studies on aphid–parasitoid interactions at the community level. However, morphological identification of Aphidiinae species remains problematic even for specialists and is almost impossible with larval stages. Here, we compared the efficiency of two molecular markers [mitochondrial cytochrome c oxydase I (COI) and nuclear long wavelength rhodopsin (LWRh)] that could be used to accurately identify about 50 species of Aphidiinae that commonly occur in aphid–parasitoid networks in northwestern Europe. We first identified species on a morphological basis and then assessed the consistency of genetic and morphological data. Probably because of mitochondrial introgression, Aphidius ervi and A. microlophii were indistinguishable on the basis of their COI sequences, whereas LWRh sequences discriminated these species. Conversely, because of its lower variability, LWRh failed to discriminate two pairs of species (Aphidius aquilus, Aphidius salicis, Lysiphlebus confusus and Lysiphlebus fabarum). Our study showed that no unique locus but a combination of two genes should be used to accurately identify members of Aphidiinae.     

Early development and differentiation of the Laysan albatross (Phoebastria immutabilis (Rothschild, 1893): Procellariiformes)

Bird incubation is subdivided into two phases: differentiation (embryonic phase) and growth (fetal phase). Most birds have a relatively short incubation period (20–30 days) with the phase transition occurring midway through the incubation period. The Laysan albatross (Phoebastris immutabilis) is a large pelagic bird with a long incubation period. The purpose of this study was to document the differentiation phase with the aim of ascertaining the impact of a lengthened incubation on embryonic development. Eighty‐two previously collected albatross embryos were examined, measured, and staged. The albatross was found to develop more slowly than smaller birds, with a rate similar to other long‐incubating birds. Legs and wings grow at similar rates but exhibit variation in growth among their anatomical components. While the albatross embryos shared some morphological stages with chickens, they were more similar to ducks and pelicans. Special features of the albatross not shared with the Gallianserae (chickens and ducks) included an alligator‐like curved tail, narial tubes, and a cloacal bulge. Further examination of other larger pelagic birds with long incubation periods are needed to determine the uniqueness of the Laysan albatross embryonic development. Although much embryonic phase growth was documented in the postnatal period, little is known about the later, fetal phase in Laysan albatross. Future studies should involve examination of later (post day 32) fetuses. J. Morphol. 277:1231–1249, 2016. © 2016 Wiley Periodicals, Inc.