A Study of Feeding in Some Inshore Reef Fish of the Natal Coast,South Africa

A detailed quantitative investigation of the feeding habits of seven important Natal inshore reef fish (Epinephelus andersoni Boulenger, 1903, Coracinus mulfifasciafus (Pellegrin, 1914), Pomadasys olivaceum Day, 1875, Diplodus sargus Linnaeus, 1758, Sarpa salpa (Linnaeus, 1766), Acanthurus triosfegus Linnaeus, 1758 and Neoscorpls lithophilus (Gilchrist & Thompson, 1908)) is described. Qualitative information on the feeding of 23 other species is also given, and when all species are considered the ratio of carnivores, omnivores and herbivores is 4:1:1.     

Use of Eggs Derived From the Interspecific Charr Hybrids to Induce Androgenetic Development of the Brook Charr (Salvelinus fontinalis Mitchill 1814)

Although, brook charr (Salvelinus fontinalis Mitchill 1814) and Arctic charr (Salvelinus alpinus Linnaeus 1758) are able to cross and give fertile offspring, their androgenetic nucleocytoplasmic hybrids are not viable. To overcome incompatibility between the egg cytoplasm of one charr species and the sperm nucleus of another charr species, application of F₁ interspecific hybrids as egg donors for the purpose of androgenesis has been proposed. Here, androgenetic development of the brook charr was successfully induced in the brook charr eggs and the eggs derived from the reciprocal brook charr × Arctic charr F₁ hybrids. A working androgenesis protocol included inactivation of the maternal nuclear DNA achieved by irradiation of the eggs with 420 Gy of X‐rays, insemination of such treated eggs with the haploid sperm cells and exposition of the haploid androgenetic zygotes to the high hydrostatic pressure shock (51.711 MPa for 4 min) applied 420 min after insemination. Androgenetic larvae that hatched from the brook charr and the hybrid eggs were shown to be homozygous brook charr individuals. Androgenetic individuals exhibited 84 chromosomes and 100 chromosome arms (FN), values characteristic for the brook charr diploid cells. Strategy hybridize first than induce androgenesis should be tested in order to provide androgenetic offspring in other salmonids that are able to cross and produce fertile offspring.     

Inter‐specific and intra‐specific variability in fruit color preference in two species of Turdus

One of the main hypotheses proposed to explain the evolution of fruit color deals with a preference of avian frugivores for specific colors, mainly black and red, which are the most common fruit colors in many of the studied habitats. I analyzed fruit color preferences by wild birds belonging to 2 species of the highly frugivorous genus Turdus (Eurasian Blackbird Turdus merula Linnaeus, 1758 and Redwing Turdus iliacus Linnaeus, 1758) by means of captivity experiments with artificial fruits. Despite important within‐individual (i.e. temporal) and among‐individual variability, consistent patterns of species‐specific color preferences emerged. Eurasian Blackbirds tended to prefer red over blue, green and black, whereas Redwings seemed to prefer black over the rest. Green was systematically avoided by both species, suggesting that it might signal unripeness of fruits. Both preferred colors have been previously reported as the most common among fleshy‐fruited plants. The high variability, both within and between individuals, in preferences suggests that they can be subject to changes through experience and learning and, therefore, are not likely to drive the evolution of fruit color. The main differences between both species could be related to the most common fruit color they fed upon during the last months before capture.     

Occurrence of Moniezia expansa (Rud, 1810) Blanchard, 1891 (Cestoda: Anoplocephalidae) in domestic pig (Sus scrofa domestica Linnaeus, 1758) in Perú

The presence of Moniezia expansa (Rud, 1810) Blanchard, 1891, is reported in domestic pig (Sus scrofa domestica Linnaeus, 1758). Four tapeworms were collected and identified as M. expansa. This is the first report of M. expansa collected in a domestic pig in Perú.     

Using dogs for tiger conservation and research

This paper is a review of the history, development and efficacy of using dogs in wildlife studies and considers the use of dogs in the research and conservation of wild tigers (Panthera tigris Linnaeus, 1758). Using scat detection dogs, scent-matching dogs, law enforcement detection dogs and protection dogs are proven methods that can be effectively used on tigers. These methods all take advantage of the dog's extremely evolved sense of smell that allows them to detect animals or animal byproducts (often the focus of tiger studies). Dogs can be trained to communicate this information to their handlers.     

Impact of Prosopis (mesquite) invasion and clearing on vegetation species composition and diversity in semi-arid Nama-Karoo rangeland,South Africa

The Nama-Karoo biome occupies 28% of South Africa’s land area. Alien leguminous trees of the genus Prosopis have invaded large tracts of Nama-Karoo rangeland. We evaluated the impact of Prosopis invasion and clearing on vegetation species composition and diversity (alien and indigenous species richness and cover) in Nama-Karoo rangeland on two sheep farms in the Beaufort West district of the Western Cape province of South Africa. Our results suggest that Prosopis invasion and clearing can significantly change Nama-Karoo rangeland species composition. Invasion and clearing appear to have no effect on alien species richness. Invasion, however, increases alien species cover, while clearing restores it to pre-invasion levels. In contrast, invasion reduces indigenous species richness while clearing restores it to pre-invasion levels. Invasion appears to have no effect on indigenous species cover. This lack of effect appears to be the serendipitous result of a site-specific trade-off between a decline in cover of grasses that are negatively affected by Prosopis invasion and a concomitant increase in the cover of positively affected grasses. Clearing increases indigenous species cover to above pre-invasion levels. The higher than usual indigenous species cover after clearing could be a transient legacy of Prosopis soil nutrient enrichment.     

A comparative analysis of sphenoid bone between domestic sheep (ovis aries) and goat (capra hircus) using geometric morphometrics

The sphenoid bone forms the rostral part of the base of the neurocranium and is composed of two segments, the presphenoid [os praesphenoidale] and the basisphenoid [os basisphenoidale]. Rarely studied in osteology, we tested whether it can provide distinctive features between domestic sheep (Ovis aries L., 1758) and goat (Capra hircus L., 1758). For this goal, we studied a sample comprised by 53 dry modern skulls of adult sheep (n = 36) and goat (n = 17) subjects from a modern comparative collection by means of geometric morphometric techniques using a total of 26 anatomical points (2 saggital landmarks and 24 semilandmarks). Results showed that form (size + shape) differences appear between both species: sphenoid among sheep tends to be bigger, longer and wider than in goats, differences of width being mainly located on basisphenoid width.     

Identification of a novel filovirus in a common lancehead (Bothrops atrox (Linnaeus, 1758))

I performed metaviromic analysis of publicly available RNA-seq data from reptiles to understand the diversity of filoviruses (family Filoviridae). I identified a coding-complete sequence of a filovirus from the common lancehead (Bothrops atrox (Linnaeus, 1758)), tentatively named Tapajós virus (TAPV). Although the genome organization of TAPV is similar to mammalian filoviruses, our phylogenetic analysis showed that TAPV forms a cluster with a fish filovirus. However, TAPV is still distantly related to all the known filoviruses, suggesting that TAPV can be assigned as a species of a novel genus in Filoviridae. To our knowledge, this is the first report identifying a filovirus in reptiles, and thus contributes to a deeper understanding of the diversity and evolution of filoviruses.     

Efficacy of anticoagulant-free alternative bait products against house mice (Mus musculus) and brown rats (Rattus norvegicus)

The attractiveness and efficacy of four anonymous anticoagulant-free alternative rodenticides (active ingredients cellulose or plaster) were tested on wild strain groups of house mice (Mus musculus Linnaeus) and brown rats (Rattus norvegicus Berkenhout) in laboratory choice and no-choice experiments. In no-choice tests, the rodenticide product was offered ad libitum to the animals for 21 days (mice) and 10 days (rats), respectively. In choice tests, the rodenticide product and non-poisoned food were offered for 28 days (mice) and 14 days (rats). Two products with cellulose (C1 and C2) as the active ingredient were tested against both mice and rats. In two no-choice tests with mice, all animals died within 14 days (C1) and 21 days (C2); in a third no-choice test, 11% (2/18) of mice survived (C1: 21 days). In all three tests, numerous incidents of cannibalism were observed. The attractiveness of cellulose baits was tested for one product (C1) in three trials against normal food pellets. In all trials, bait consumption was low and all mice survived (15–34 days). Two no-choice trials with cellulose baits (C1) were conducted on groups of Rattus norvegicus; 11 of 12 rats survived the bait feeding period and no cannibalism or sign of aggression between conspecifics was observed. Two plaster-based (CaSO₄·0.5H₂O) products (P1 and P2) were tested against both mice and rats; in no-choice tests, only one mouse (n= 20) and no rats (n= 8) were killed, although the baits proved to be attractive for rats and mice in choice tests. The results of these experiments suggest that neither cellulose-based nor plaster-based rodenticides are suitable agents for the control of Mus musculus and Rattus norvegicus.     

Invasion of a South African Anguilla mossambica (Anguillidae) opulation by the alien gill worm Pseudodactylogyrus anguillae (Monogenea)

The parasitic gill monogenean Pseudodactylogyrus anguillae is alien to Africa. In an investigation of 227 longfin eel, Anguilla mossambica, and 26 mottled eel, Anguilla marmorata, sampled from four river systems in the Eastern Cape, South Africa, this parasite was only present on the gills of A. mossambica sampled from the Great Fish River system. In the Great Fish River, it infected 73.2% of the sampled population at a mean intensity of 63.8±34.3 parasites per fish. High prevalence and intensity are indicative of a well-established alien invasive parasitic species. Results showing the absence of P. anguillae from the co-occurring but less abundant A. marmorata indicate that this species may be less susceptible to P. anguillae infection.     

Molecular identification of Anisakis spp. from fishes collected in the Tyrrhenian Sea (NW Mediterranean)

The accurate identification of anisakid nematodes at any life cycle stage is important both to deepen the knowledge on their taxonomy, ecology, epidemiology and for diagnosis and control, as larval stages cause a clinical disease in humans known as anisakidosis. With the aim to investigate the presence of anisakid larvae, specimens of horse mackerel, Trachurus trachurus (Linnaeus, 1758), silver scabbardfish, Lepidopus caudatus (Euphrasen, 1788), European anchovy, Engraulis encrasicolus (Linnaeus, 1758) and opah fish, Lampris guttatus (Brunnich, 1788), were collected by trawling at depths ranging from 50 to 400 m. A molecular approach based on restriction profiles obtained after digestion of the nuclear ribosomal ITS region was used to identify Anisakis spp. larvae recovered in fish samples. Restriction profiles showed three banding patterns, corresponding to Anisakis pegreffii, Anisakis physeteris and to heterozygote pattern between A. pegreffii and Anisakis simplex s.s. Specimens showing the heterozygote restriction pattern were also analyzed by sequencing of the entire ITS region, to confirm the heterozygote status.     

Factors affecting the breeding success of the African Black Oystercatcher (Haematopus moquini): a perspective on protection and food availability

Breeding success (fledglings pair^?1 y^?1) of the Red-listed African Black Oystercatcher (Haematopus moquini) is highly variable, both spatially and temporally. Despite a diversity of natural factors causing this variability, there is evidence that two anthropogenic factors, i.e. disturbance and an introduced mussel (Mytilus galloprovincialis), are having an impact on the local breeding success of this species. Using a data set comprising 87 site-years of nest-monitoring data across most of the species’ breeding range, we analysed the extent and causes of variability in breeding success. Breeding success differed across three population categories defined by varying levels of human disturbance: island populations, protected mainland populations, and unprotected mainland populations. Differences in breeding success between island populations and protected mainland populations were likely due to differing exposure to predators; however, differences between protected and unprotected mainland populations were unlikely caused by this as both experience equivalent predation levels (although from different predators). Protection only improved the breeding success of oystercatchers in very high-quality habitats (with a high biomass of alien mussels), and where populations were ‘released’ from high levels of human disturbance. In unprotected mainland areas, human activity impacted on the breeding success of local populations primarily through predation of small chicks by uncontrolled dogs, and by rising tides drowning chicks that were hiding from human disturbance. The findings of this study note the potential conservation dilemma resulting from an invasive species improving the conservation status of a Red-listed species, and encourage the implementation of restricted sites in high-quality habitats with high breeding pair densities.     

Gill Reaction to Pollutants from the Tamiš River in Three Freshwater Fish Species,Esox lucius L. 1758, Sander lucioperca (L. 1758) and Silurus glanis L. 1758: A Comparative Study

The study evaluated the effects of waterborne pollutants from the Tami? River on gill histology and possible differences in gill reaction patterns between three freshwater fish species, pike Esox lucius L. 1758, pike‐perch Sander lucioperca (L. 1758) and wels catfish Silurus glanis L. 1758 from the Tami? River. Gills from analysed fish species showed moderate to intense histopathological alterations. The most frequent progressive alteration was hyperplasia of epithelium, whereas the most frequent regressive alteration was epithelial lifting. Circulatory disturbances were most often manifested in the form of hyperaemia. During comparative analysis, differences in gill indices, reaction and alteration indices, as well as in gill and filament prevalence between analysed species, were observed. Although all analysed fish species did show both progressive and regressive alterations, there was a significant difference in the level of expression of these reaction patterns. Gill index obtained for pike clearly stands out as the lowest. Wels catfish showed the highest progressive reaction index, significantly higher in comparison with the other two species (P < 0.05), while pike‐perch showed the highest regressive reaction index, also significantly higher in comparison with the other species (P < 0.001). These results may implicate species‐specific gill reactions and thus present a useful tool for better understanding toxic mechanisms of various pollutants.     

Trichostrongylus auriculatus n. sp. (Nematoda: Trichostrongylidae) from the steenbok, Raphicerus campestris (Thunberg, 1811)

During a pilot survey of the parasites of some artiodactylids in the Kalahari Gemsbok National Park a new species of Trichostrongylus Looss, 1905 was recovered from the small intestine of a steenbok, Raphicerus campestris (Thunberg, 1811), a gemsbok, Oryx gazella (Linnaeus, 1758), and a red hartebeest, Alcelaphus buselaphus (Pallas, 1766). The male spicules were 0,120-0,148 mm long and an ear-shaped protuberance was present on the shaft of the left spicule. The presence of only a single protuberance is characteristic of the species.     

Grain,pellet and wax block bait take by the house mouse (Mus musculus) and non‐target species: implications for mouse eradications on coral cay islands

Introduced rodents have been eradicated from large numbers of offshore islands using toxic baits; however, toxic baits have been linked with negative impacts on non‐target species. The present study assessed the bait take of target (house mouse, Mus musculus) and non‐target (buff banded rail, Rallus philippensis) animals on Northwest and Heron Islands in the Great Barrier Reef. Three non‐toxic bait formulations (wax block, pellet and grain) were tested and each was applied at 1 kg ha^?1 in six treatment grids. The tracks of animals visiting the baits were identified using 30 tracking stations per treatment grid. A tracking station consisted of a track‐board placed in the centre of a sand‐pad. Mean bait take differed significantly between the formulations: birds took more grain bait than wax block bait; mice took more wax block than grain bait. Both mice and birds were equally selective of pellet bait. Thus, the findings indicate that wax blocks are the most suitable formulation for future baiting programs to eradicate mice on these and other islands.     

Population increase and changes in behavior and morphology in the Critically Endangered Redonda ground lizard (Pholidoscelis atratus) following the successful removal of alien rats and goats

Redonda is a small volcanic Caribbean island that is home to at least 4 endemic lizard species, including the Critically Endangered ground lizard (Pholidoscelis atratus). Black rats (Rattus rattus) and domestic goats (Capra hircus) were introduced to the island at some time after its discovery by Europeans in the late 1500s. They had a devastating effect on the island, resulting in the loss of nearly all trees and most of the ground vegetation. Point count surveys of P. atratus in 2012 indicated low densities, and the invasive rats were observed hunting and preying on the lizards. Both populations of rats and goats were successfully removed in 2017 as part of an ecological restoration program, and native vegetation and invertebrate populations have increased rapidly since. Population surveys in 2017, 2018, and 2019 show the lizard population has increased by more than sixfold. In 2017, as rats and goats were being removed, we evaluated the morphology and escape behavior of this species and repeated these measurements 1 year later. We observed that P. atratus had become bolder, with a reduced flight distance. We also detected changes in limb morphology related to locomotion and suggest possible explanations that will need to be further investigated in the future. These results show how the removal of invasive species can rapidly affect lizard population recovery and behavior, potentially restoring island ecosystems to their pre-human interference dynamics.     

Aspects on the relief of living surfaces using atomic force microscopy allow “art” to imitate nature

The visualization of the surface of biological samples using an atomic force microscope reveals features of the external relief and can resolve very fine and detailed features of the surface. We examined specimens from the skin of the amphibians Salamandra salamandra Linnaeus, 1758, Lyciasalamandra luschani basoglui Baran & Atatür, 1980 and Mesotriton alpestris Laurenti, 1768, and from the surface of pollen grains of the plant species Cyclamen graecum Link, 1835 and Cistus salviifolius Linnaeus, 1753, which exhibit certain interesting features, imaged at the nanoscale level. It is likely that the relief influences the attributes of the interfaces between the tissues and the environment. We found that the microsculpture increases in size the surface of the examined tissues and this might be particularly important for their performance in the field. Microsculpturing of amphibians' skin may affect water regulation, dehydration and rehydration, and cutaneous gas exchange. Pollen grain relief might affect the firmness of the contact between pollen surface and water droplets. High resolution imaging of the external relief showed that roughening might induce wetting and influence the water status of the specimens. In addition, roughness affects the radius of water droplets retained in between the projections of the external relief. Roughness of the tissues was highly correlated with their vertical distance, whereas surface distances were highly correlated with horizontal distances. By enabling a more detailed characterization of the external sculptures, through sophisticated techniques, a more comprehensive examination of the samples indicates similarities among different living tissues, originated from different kingdoms, which can be attributed to environmental conditions and physiological circumstances.