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1.
Urban Ecosyst ; 18(2): 465-475, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26190913

RESUMO

Supplementary feeding of wild birds by domestic garden-holders is a globally widespread and popular form of human-wildlife interaction, particularly in urban areas. Vast amounts of energy are thus being added to garden ecosystems. However, the potential indirect effects of this activity on non-avian species have been little studied to date, with the only two previous studies taking place under experimentally manipulated conditions. Here we present the first evidence of a localised depletive effect of wild bird feeding on ground beetles (Coleoptera: Carabidae) in suburban gardens under the usual feeding patterns of the garden-holders. We trapped significantly fewer ground beetles directly under bird-feeding stations than in matched areas of habitat away from feeders. Video analysis also revealed significantly higher activity by ground-foraging birds under the feeding stations than in the control areas. Small mammal trapping revealed no evidence that these species differ in abundance between gardens with and without bird feeders. We therefore suggest that local increases in ground-foraging activity by bird species whose diets encompass arthropods as well as seed material are responsible for the reduction in ground beetle numbers. Our work therefore illustrates that providing food for wild birds can have indirect negative effects on palatable prey species under typical conditions.

2.
Zootaxa ; 5306(3): 377-384, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37518516

RESUMO

All examples of Anthrenus (Anthrenus) festivus were borrowed from the Natural History Museum, London for dissection to provide good images of external and internal features. Images of habitus, ventrites and antennae are presented along with aedeagus and sternite IX. The purpose of this was to provide clear information for future comparative taxonomic studies. During the examination of the specimens, a new species was discovered that had been collected in Bombay (Mumbai) in the late 19th century. Images of external and internal features of the holotype (male) and paratype (female) are provided. The new species is named Anthrenus (Anthrenus) mumbaiensis after the location of collection. Collection data from the study specimens, Andreas Herrmann's private collection, the literature, and verifiable images on iNaturalist were used to generate a distribution map. The map showed that A. festivus is found mainly in coastal regions of the western Mediterranean.


Assuntos
Besouros , Masculino , Feminino , Animais , Índia , Distribuição Animal
3.
Zootaxa ; 5323(1): 126-132, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37518197

RESUMO

During an examination of Spanish Anthrenus spp. held in Andreas Herrmann's private collection, four specimens of a new species were noted: Anthrenus (Anthrenus) semipallens. Images of habitus features, including antenna, are presented and compared with other Anthrenus species thought to occur in Spain. A. semipallens is small so some comparison species could be eliminated courtesy of size. Although A. semipallens doesn't resemble the colour pattern of any other species, the possibility that A. semipallens is an unknown colour variant of a comparison species was considered. The A. semipallens specimens were dissected and the aedeagus compared with aedeagi from all other possible species. There was no similarity. Anthrenus semipallens is a valid new species.

4.
Zootaxa ; 5244(2): 197-200, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-37044467

RESUMO

N/A.


Assuntos
Besouros , Animais , Turquia , Grécia
5.
Zootaxa ; 4991(3): 555-560, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34186830

RESUMO

A new species from Turkey, Anthrenus (s. str.) corona, belonging to the Anthrenus pimpinellae complex is presented. The species is described from a single specimen discovered in the collection held by the Natural History Museum, London. The species was uncovered during the dissection of many specimens for the purpose of curation. The species is compared in detail to A. goliath, the most likely confusion species. An obvious external feature of the specimen is its large size, putting it apart from nearly all other species within the complex. The parameres and median lobe are slim, differing in many ways from A. goliath.


Assuntos
Besouros/anatomia & histologia , Besouros/classificação , Animais , Museus , Turquia
6.
Animals (Basel) ; 11(1)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33430010

RESUMO

The Eurasian Black Vulture is a globally threatened raptor that in Southeast Europe only occurs in an isolated population in Greece. We examined the population viability for the species under demographic fluctuations and conservation scenarios. The current population showed no possibility of extinction for the next 100 years. However, simulated scenarios showed that the most important factor affecting the viability of the species was medium and high poisoning, leading to 94.8% and 100% probability of extinction, respectively. Furthermore, high reduction of supplementary feeding highlighted an 18.6% extinction possibility. Also, a high increase of wind farms in the area may result in 17.4% extinction possibility. Additionally, the non-establishment of the feeding station in 1987 in the study area would have resulted in an extinction risk of 7%. The species can be translocated to the Olympus National Park by releasing 80 juveniles over 10 years. The implementation of the conservation scenarios concerning the establishment of a supplementary feeding site network, and the reintroduction of the Eurasian Black Vulture in its historic range, along with the elimination of threats posed by poisoning, low food availability, and wind farms would increase the probability of the species persistence and allow the population to become a source for dispersal across Southeast Europe.

7.
Zootaxa ; 4543(4): 595-599, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30647290

RESUMO

A new species, Anthrenus amandae sp. nov., from Mallorca, Spain is described and illustrated. The species differs from likely confusion species on the basis of a combination of habitus morphometrics, antennal and male genitalia structure.


Assuntos
Besouros , Animais , Masculino , Espanha
8.
PLoS One ; 14(1): e0210440, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30625231

RESUMO

Pesticide resistance is normally associated with genetic changes, resulting in varied responses to insecticides between different populations. There is little evidence of resistance to plant allelochemicals; it is likely that their efficacy varies between genetically diverse populations, which may lead to the development of resistance in the future. This study evaluated the response of Anopheles gambiae (larvae and adults) from spatially different populations to acetone extracts of two botanicals, Piper guineense and Eugenia aromatica. Mosquito samples from 10 locations within Akure metropolis in Southwest Nigeria were tested for variation in susceptibility to the toxic effect of botanical extracts. The spatial distribution of the tolerance magnitude (T.M.) of the mosquito populations to the botanicals was also mapped. The populations of An. gambiae manifested significant differences in their level of tolerance to the botanicals. The centre of the metropolis was the hot spot of tolerance to the botanicals. There was a significant positive correlation between the adulticidal activities of both botanicals and initial knockdown. Hence, knockdown by these botanicals could be a predictor of their subsequent mortality. In revealing variation in response to botanical pesticides, our work has demonstrated that any future use of botanicals as alternative environmentally friendly vector control chemicals needs to be closely monitored to ensure that resistance does not develop.


Assuntos
Anopheles/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Animais , Cidades , Flores/química , Geografia , Resistência a Inseticidas/efeitos dos fármacos , Larva/efeitos dos fármacos , Nigéria , Sementes/química
10.
R Soc Open Sci ; 3(10): 160368, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27853552

RESUMO

Species occurring at low density can be difficult to detect and if not properly accounted for, imperfect detection will lead to inaccurate estimates of occupancy. Understanding sources of variation in detection probability and how they can be managed is a key part of monitoring. We used sightings data of a low-density and elusive raptor (white-headed vulture Trigonoceps occipitalis) in areas of known occupancy (breeding territories) in a likelihood-based modelling approach to calculate detection probability and the factors affecting it. Because occupancy was known a priori to be 100%, we fixed the model occupancy parameter to 1.0 and focused on identifying sources of variation in detection probability. Using detection histories from 359 territory visits, we assessed nine covariates in 29 candidate models. The model with the highest support indicated that observer speed during a survey, combined with temporal covariates such as time of year and length of time within a territory, had the highest influence on the detection probability. Averaged detection probability was 0.207 (s.e. 0.033) and based on this the mean number of visits required to determine within 95% confidence that white-headed vultures are absent from a breeding area is 13 (95% CI: 9-20). Topographical and habitat covariates contributed little to the best models and had little effect on detection probability. We highlight that low detection probabilities of some species means that emphasizing habitat covariates could lead to spurious results in occupancy models that do not also incorporate temporal components. While variation in detection probability is complex and influenced by effects at both temporal and spatial scales, temporal covariates can and should be controlled as part of robust survey methods. Our results emphasize the importance of accounting for detection probability in occupancy studies, particularly during presence/absence studies for species such as raptors that are widespread and occur at low densities.

11.
Ecol Evol ; 6(4): 1092-103, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-26941945

RESUMO

The White-headed Vulture Trigonoceps occipitalis (WhV) is uncommon and largely restricted to protected areas across its range in sub-Saharan Africa. We used the World Database on Protected Areas to identify protected areas (PAs) likely to contain White-headed Vultures. Vulture occurrence on road transects in Southern, East, and West Africa was adjusted to nests per km(2) using data from areas with known numbers of nests and corresponding road transect data. Nest density was used to calculate the number of WhV nests within identified PAs and from there extrapolated to estimate the global population. Across a fragmented range, 400 PAs are estimated to contain 1893 WhV nests. Eastern Africa is estimated to contain 721 nests, Central Africa 548 nests, Southern Africa 468 nests, and West Africa 156 nests. Including immature and nonbreeding birds, and accounting for data deficient PAs, the estimated global population is 5475 - 5493 birds. The identified distribution highlights are alarming: over 78% (n = 313) of identified PAs contain fewer than five nests. A further 17% (n = 68) of PAs contain 5 - 20 nests and 4% (n = 14) of identified PAs are estimated to contain >20 nests. Just 1% (n = 5) of PAs are estimated to contain >40 nests; none is located in West Africa. Whilst ranging behavior of WhVs is currently unknown, 35% of PAs large enough to hold >20 nests are isolated by more than 100 km from other PAs. Spatially discrete and unpredictable mortality events such as poisoning pose major threats to small localized vulture populations and will accelerate ongoing local extinctions. Apart from reducing the threat of poisoning events, conservation actions promoting linkages between protected areas should be pursued. Identifying potential areas for assisted re-establishment via translocation offers the potential to expand the range of this species and alleviate risk.

12.
Pest Manag Sci ; 68(9): 1265-71, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22605686

RESUMO

BACKGROUND: Bruchid beetles, Callosobruchus species, are serious pests of economically important grain legumes; their activity in stores is often controlled by the use of synthetic insecticides. Esterases are known to be involved in insecticide resistance in insects. However, there is a dearth of information on esterase activity in the genus Callosobruchus. In this study, the effect of species, geographical strain and food type on the variation in acetylcholinesterase (AChE) activity and its inhibition by malaoxon (malathion metabolite) was investigated using an in vitro spectrophotometric method. RESULT: AChE activity varied significantly among species and strains and also among legume type used for rearing them. Generally, irrespective of species, strain or food type, the higher the AChE activity of a population, the higher is its inhibition by malaoxon. C. chinensis had the highest AChE activity of the species studied, and in the presence of malaoxon it had the lowest remaining AChE activity, while C. rhodesianus retained the highest activity. CONCLUSION: A first-hand knowledge of AChE activity in regional Callosobruchus in line with the prevailing food types should be of utmost importance to grain legume breeders, researchers on plant materials for bruchid control and pesticide manufacturer/applicators for a robust integrated management of these bruchids.


Assuntos
Inibidores da Colinesterase/toxicidade , Besouros/efeitos dos fármacos , Besouros/enzimologia , Proteínas de Insetos/antagonistas & inibidores , Inseticidas/toxicidade , Malation/análogos & derivados , Organofosfatos/toxicidade , Acetilcolinesterase/metabolismo , Animais , Brasil , Camarões , Besouros/classificação , Besouros/fisiologia , Fabaceae/parasitologia , Comportamento Alimentar/efeitos dos fármacos , Proteínas de Insetos/metabolismo , Malation/toxicidade , Doenças das Plantas/parasitologia , Especificidade da Espécie , Iêmen
13.
Evolution ; 47(4): 1229-1239, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28564295

RESUMO

Ladybirds (Coccinellidae) defend themselves against attack by vertebrate predators by exuding a fluid from the femero-tibial joints. This fluid carries a noxious or toxic alkaloid. The amount of fluid produced during a single attack can be very high (up to 20% of fresh body weight), and the weight of the self-synthesized alkaloid can amount to several percent of the weight of the fluid. A study was carried out on these two defense characters and two other fitness characters (body weight and growth rate) to demonstrate a cost to defense in the form of genetic trade-offs between characters. The two sexes were analyzed separately, and a jackknife procedure was used to attach errors to the estimates of Va and cova . All four characters were associated with high levels of Va , but the cova values were mixed, some being negative and others positive. Principal-component analysis indicated the operation of factors constraining the cova values in males, and further possible reasons for the appearance of so many positive values are explored. A matrix analysis showed that the genetic variance/covariance matrices of the two sexes were significantly different from each other. Breeding values derived from sons plotted on breeding values from daughters had correlation coefficients significantly less than +1. This finding indicated that a substantial amount of sex-dependent gene expression was occurring.

14.
Ecotoxicol Environ Saf ; 52(2): 128-33, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12061829

RESUMO

Fourth-instar Chironomus riparius Meigen larvae were exposed to the organophosphate (OP) insecticide pirimiphos methyl (0, 0.1, 1.0, and 10 microg/L) for 48, 72, or 96 h at three temperatures (3, 12, or 22 degrees C). Two biochemical biomarkers, acetylcholinesterase (AChE) and glutathione S-transferase (GST), were measured in individual larvae from each treatment. AChE activity was inhibited by the OP in a dose-responsive fashion. This response remained similar at all three temperatures, demonstrating that AChE is a robust and specific biomarker. Exposure duration had little effect on AChE activity. In contrast, GST activity was induced at the highest OP insecticide concentration, but induction was also evident at 3 degrees C. There was a significant effect of exposure duration, with an overall decline in GST activity over time. This result agrees with previous work suggesting that GSTs are not particularly suitable for use as a biomarker of pesticide exposure or effect in Chironomus.


Assuntos
Acetilcolinesterase/análise , Chironomidae/fisiologia , Exposição Ambiental , Glutationa Transferase/análise , Inseticidas/efeitos adversos , Compostos Organotiofosforados/efeitos adversos , Acetilcolinesterase/efeitos dos fármacos , Acetilcolinesterase/farmacologia , Animais , Biomarcadores/análise , Glutationa Transferase/efeitos dos fármacos , Glutationa Transferase/farmacologia , Larva/crescimento & desenvolvimento , Sensibilidade e Especificidade , Temperatura
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