Suppression of populations of Australian sheep blowfly, Lucilia cuprina (Wiedemann) (Diptera: Calliphoridae), with a novel blowfly trap

The Australian sheep blowfly, Lucilia cuprina , initiates more than 85% of fly strikes on sheep in Australia with an estimated average annual cost of A$280 million to the Australian sheep industry. LuciTrap^® is a commercially available, selective trap for L. cuprina consisting of a plastic bucket with multiple fly entry cones and a synthetic attractant. The impact of LuciTrap on populations of L. cuprina on sheep properties in five Australian states was evaluated by comparing L. cuprina populations on paired properties with and without LuciTraps over seasons when significant fly populations could be expected. Twenty-four comparisons (trials) were conducted over 4 years. During times of 'higher fly density' (when the 48 h geometric mean of trap catches on the control property was greater than five L. cuprina ), the overall geometric mean trap catches for control and trapped properties differed significantly ( P  < 0.001) with mean trap catches of 19.4 and 7.74 L. cuprina , respectively. The selectivity of the LuciTrap was confirmed with 59% of all trapped flies being L. cuprina . Chrysomya spp. and Calliphora spp. constituted 9.3% and 1.1% of the catches with a variety of other flies (mainly Sarcophagidae and Muscidae ) providing the remainder (31%). Lucilia sericata was only trapped in Tasmania and made up 7.7% of the Lucilia spp. catch in that state. Seventy-two per cent of the trapped L. cuprina were female. The deployment of LuciTrap on sheep properties at one trap per 100 sheep from the beginning of the anticipated fly season suppressed the populations of L. cuprina by 60% compared with matched control properties. The LuciTrap is a selective and easy to use fly trap and constitutes an effective, non-insecticidal tool for use in integrated management programs for L. cuprina .     

Scarring patterns and relative mortality rates of Indian Ocean whale sharks

This study recorded the scarring rate and severity for whale sharks Rhincodon typus from three Indian Ocean aggregations (Australia, Seychelles and Mozambique), and examined whether scarring (mostly attributed to boat strikes and predator attacks) influences apparent survival rates using photo‐identification libraries. Identifications were based on spot‐and‐stripe patterns that are unique to individual whale sharks. Scarring was most prevalent in the Seychelles aggregation (67% of individuals). Predator bites were the most frequent source of scarring (aside from minor nicks and abrasions) and 27% of individuals had scars consistent with predator attacks. A similar proportion of whale sharks had blunt trauma, laceration and amputation scars, the majority of which appeared to be caused by ship collisions. Predator bites were more common (44% of individuals) and scars from ship collisions were less common at Ningaloo Reef than at the other two locations (probability of among‐site differences occurring randomly = 0·0007 based on a randomized multinomial contingency analysis). In all aggregations, scars occurred most often on the caudal fin, which may result from the fin being the body part closest to the surface when boats pass over, or they may provide a large target for predator attack. No evidence was found for an effect of scarring on apparent survival (φ; mean ±s .e .) for the Ningaloo (not scarred φ= 0·858 ± 0·033; scarred φ= 0·929 ± 0·033) or Seychelles populations (not scarred φ= 0·502 ± 0·060; scarred φ= 0·538 ± 0·070). The lower apparent survival of the Seychelles population may be attributed to a high number of transient whale sharks in this aggregation that might bias estimates. This study indicates that while scarring from natural predators and smaller vessels appears to be unrelated to whale shark survival, the effect of deaths related to ship strike need to be quantified to assist in future management of this species.     

样线法和网捕法在机场鸟情调查中的应用比较

鸟击事件主要发生在机场范围内,对机场周边生境的鸟类组成进行调查,是制定鸟击防范对策的重要前提。国内多数机场已经开展了相关的鸟类组成调查,但是选用的调查方法却存在较大差异。以样线法和网捕法两种常用的调查方法对沈阳桃仙国际机场周边的迁徙期鸟类进行了研究,旨在比较两种调查方法在机场鸟类群落组成调查中的效果及调查的鸟类群落组成差异。结果表明：两种方法均适合机场鸟类调研,共记录到鸟类97种,网捕法记录的鸟类种数(83种vs. 57种)高于样线法,网捕法单独记录的鸟类种数(40种vs. 14种)也高于样线法。尽管两种方法每期(半个月)调查的物种数和目的数量无明显差别,但随调查强度(如调查次数)增加,网捕法累计记录到的鸟类种类明显高于样线法,且较晚达到渐近线。另外,两种方法调查记录的鸟类群落组成也具有显著的差别,如网捕法记录到较多鹌鹑和鸮形目等夜间迁徙或活动鸟类,而样线法可记录到鹭科和雁鸭类水鸟等。这说明两种调研方法在鸟类调查中有较好的互补性。因此,本研究认为机场鸟情调研时应该根据鸟情特点,选择合适的鸟类调研方法,综合采用多种调研方法可更有利于获得科学的鸟情信息。     

The seasonal pattern of sheep blowfly strike in England and Wales

Abstract. Information on 4049 cases of sheep blowfly strike on 495 farms in England and Wales was gathered in a longitudinal survey conducted in 1991. The breech was the most commonly infested area, accounting for 70.9% of all strikes recorded. Body strikes accounted for 19.7% and foot strikes 11.4% of all strikes. Early in the season the incidences of both breech and body strikes were higher in ewes than in lambs, but from June to October lamb strikes predominated. The incidence of foot strike was greater in ewes than lambs throughout the year, with a peak incidence in September. Regional differences in strike incidence were evident; the highest overall incidences were recorded in the southern regions of England where peak incidence occurred earlier in the year. The highest monthly incidence risk was recorded in August in the south-east of England where there were 14.2 strikes per 1000 lambs and 4.0 strikes per 1000 ewes at risk. The importance of faecal soiling and ambient temperature are discussed.     

Handbook of the Birds of the World,Volume 14: Bush-Shrikes to Old World Sparrows

The Kotoka International Airport in Accra, the capital city of Ghana, has in recent years been confronted with increased presence of birds posing great challenges to aviation safety due to a high risk of bird strikes. As part of measures to mitigate the negative impacts of increasing numbers of birds, a species-specific bird strike risk index (SSBR) was modelled and calculated for a total of 86 species recorded within and near the airport. Based on the SSBR index, four species were classified as ‘critical risk’ and another four species as ‘high risk’. All six species, namely Corvus albus, Necrosyrtes monachus, Milvus migrans parasitus, Bubulcus ibis, Falco biarmicus and Falco tinnunculus, constituting 7% of the total species assemblage, were considered ‘problem species’. During the intensive, albeit short, study period, we also recorded bird strikes of N. monachus, F. biarmicus and notably M. m. parasitus. We conclude that wildlife management to avert the risk of bird strikes could be successfully achieved by adopting both proactive and reactive measures to reduce the presence of problem species at the aerodrome.     

阜阳机场鸟类多样性及其危险性

2008年6月至2010年1月,对阜阳机场及其周围5种生境(草地、农田、城镇、湿地、林地)的鸟类进行调查,并对不同季节、不同生境的鸟类多样性进行分析.结果表明:本次调查共记录到鸟类122种,隶属于15目40科;阜阳机场夏、秋季的鸟类种数显著高于冬、春季,秋季鸟类密度显著高于其他季节,夏季的鸟类多样性指数、均匀度指数均高于其他季节;在阜阳机场及其周边的5种生境中,林地的鸟类种数、密度均显著大于其他生境,林地、湿地、农田的鸟类多样性较高;对阜阳机场鸟击最危险的鸟种是麻雀、白头鹎、家燕、家鸽、喜鹊、珠颈斑鸠、灰椋鸟等.     

Addressing pain caused by mulesing in sheep

The surgical operation of mulesing cuts wool-bearing and wrinkled skin from the perineal region and adjoining hindquarters of Australian Merino sheep, and has been shown in combination with tail docking to provide significantly enhanced protection against flystrike for the remainder of the animal's life. There is strong evidence that mulesing is a painful procedure, and its medium term future is doubtful in the face of animal welfare campaigns and societal expectations. Post-surgery analgesia for mulesing is available in the form of a topical anaesthetic treatment that provides amelioration of animal behavioural and physiological responses for some hours after the procedure. However, the topical anaesthetic alone does not provide analgesia during the operation, and its duration of action is less than the indicative period of pain and discomfort that follows mulesing. Greater analgesic coverage of mulesing-induced pain would appear to require the use of a non-steroidal anti-inflammatory drug such as carprofen in combination with topical anaesthesia, but most attention on addressing the mulesing issue is now focused on the development of non-surgical mulesing alternatives, breeding sheep that do not require mulesing, and targeting the fly and its larvae through an integrated pest management (IPM) approach. Non-surgical approaches to achieving a similar conformation change to that induced by mulesing have included research on topical and intradermal administration of chemicals and bioactive agents to cause skin scarring, stretching and depilation. Agents incorporating collagenase and quaternary ammonium compounds have been evaluated and rejected, including on animal welfare grounds. Intradermal sodium lauryl sulfate administration appears to induce a relatively mild behavioural and physiological response, but further evaluation and efficacy testing are required. A physical treatment aimed at achieving a similar result to surgical mulesing involves the placement of clips to remove clamped skin folds through ischaemia. The clip treatment is commercially available, and has been shown to induce only minimal animal discomfort and inflammatory responses. Early efficacy research suggests that breech flystrike rates may not be substantially improved by the clip procedure, and its viability as a long-term replacement for mulesing remains to be determined. The availability of chemical preventative treatments that provide sheep with up to 4 months’ protection against flystrike, combined with strategies such as increased crutching (shearing dirty wool off the breech), would allow many producers to cease mulesing. However, this would be at a greater cost and with the likely exit of a proportion from the industry, unless wool value reflected a substantive price differential for non-mulesed flocks. The genetic selection of Merino sheep that do not require post-birth modification to their breech skin, in combination with a strategic IPM program, would appear to provide the most sustainable approach to managing breech flystrike in the Australian Merino. Such a breeding program requires a sustained commitment over at least a 10-year period, and is not helped by attitudes of some within the industry that conventional mulesing does not have a finite lifespan as a flystrike control option.     

Functional groups in piscivorous fishes

Piscivory is a key ecological function in aquatic ecosystems, mediating energy flow within trophic networks. However, our understanding of the nature of piscivory is limited; we currently lack an empirical assessment of the dynamics of prey capture and how this differs between piscivores. We therefore conducted aquarium‐based performance experiments, to test the feeding abilities of 19 piscivorous fish species. We quantified their feeding morphology, striking, capturing, and processing behavior. We identify two major functional groups: grabbers and engulfers. Grabbers are characterized by horizontal, long‐distance strikes, capturing their prey tailfirst and subsequently processing their prey using their oral jaw teeth. Engulfers strike from short distances, from high angles above or below their prey, engulfing their prey and swallowing their prey whole. Based on a meta‐analysis of 2,209 published in situ predator–prey relationships in marine and freshwater aquatic environments, we show resource partitioning between grabbers and engulfers. Our results provide a functional classification for piscivorous fishes delineating patterns, which transcend habitats, that may help explain size structures in fish communities.     

Development and validation of a simulation model for blowfly strike of sheep

A comprehensive simulation model for sheep blowfly strike due to Lucilia sericata (Meigen) (Diptera: Calliphoridae), which builds on previously published versions but also incorporates important new empirical data, is used to explain patterns of lamb and ewe strike recorded on 370 farms in south-west, south-east and central England and Wales. The model is able to explain a significant percentage of the variance in lamb strike incidence in all four regions, and ewe strike in three of the four regions. The model is able to predict the start of seasonal blowfly strike within one week in three of the four regions for both ewes and lambs, and within 3 weeks in the fourth region. It is concluded that the accuracy of the model will allow it to be used to assess the likely efficacy of new control techniques and the effects of changes in existing husbandry practices on strike incidence. The model could also be used to give sheep farmers advance warning of approaching strike problems. However, the ability to forecast future strike patterns is dependent on the accuracy of the weather projections; the more long-term the forecast, the more approximate the prediction is likely to be. When applied on a regional basis, model forecasts indicate expected average patterns of strike incidence and may not therefore be appropriate for individual farmers whose husbandry practices differ substantially from the average.