Sex pheromone of orange wheat blossom midge, Sitodiplosis mosellana

 Pheromone extract of the female orange wheat blossom midge, Sitodiplosis mosellana (Géhin) (SM) (Diptera: Cecidomyiidae), was analyzed by coupled gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometry (MS), employing fused silica columns coated with DB-5, DB-210, DB-23 or SP-1000. These analyses revealed a single, EAD-active candidate pheromone which was identified as 2,7-nonanediyl dibutyrate. In experiments in wheat fields in Saskatchewan, traps baited with (2S,7S)-2,7-nonanediyl dibutyrate attracted significant numbers of male SM. The presence of other stereoisomers did not adversely affect trap captures. Facile synthesis of stereoisomeric 2,7-nonanediyl dibutyrate will facilitate the development of pheromone-based monitoring or even control of SM populations. Received: 2 March 2000 / Accepted in revised form: 18 August 2000     

Sexual behavior among parasitic Megarhyssa wasps (Hymenoptera: Ichneumonidae)

Summary Male wasps of three sympatric species of Nearctic Megarhyssa (Hymenoptera: Ichneumonidae) typically form mixed-species (61.7%) aggregations composed of up to 28 males over sites of female emergence. Observations of 107 aggregations over two seasons in New York state revealed two male mating strategies: postemergence copulation on the tree surface and preemergence insemination accomplished by male abdominal insertion into the female emergence hole. Insertions by one or more males (as many as ten consecutively but not more than two simultaneously) occurred at 88% of the aggregations, with each inserting for an average of 24.8 min. Insemination as a result of preemergence insertion had a success rate of 83% while postemergence copulation attempts were successful 30% of the time (average duration 61.9 s). Individual male reproductive success was very low and not correlated with size, arrival order at emergence sites, or tenacity at the site. Males frequently aggregated at sites of male emergences as well as those of nonconspecifics, though conspecifics to the emerger ultimately played the major role at aggregations. Male-male aggression in aggregations was not apparent, though jostling occurred during the insertion period and during postemergence copulation attempts.     

Flexible foraging strategies in a diving seabird with high flight cost

How central-place foragers change search strategy in response to environmental conditions is poorly known. Foragers may vary the total distance travelled and how far they range from the central place in response to variation in the distribution of their prey. One potential reason as to why they would extend the length of their foraging trip and its distance from the colony would be to increase prey quality or quantity, despite incurring higher transit costs. To test this trade-off hypothesis in a species with high flight costs, we recorded the foraging behaviour of razorbills (Alca torca) using state-of-the-art techniques that log both individual horizontal (flight activity) and vertical (dive activity) movements. We show that the distance that razorbills travelled to foraging locations increased with sea-surface temperature, which may relate to higher prey quality or quantity. This relation is supported by an indirect index of patch quality, based on dive profiles, which also increased with travel distance from the colony. Furthermore, we show that this index was highest during the daily peak in diving activity, around midday. Taken together, these results suggest that razorbills are capable of adjusting their search strategies sensitively in response to proximate environmental cues.     

Adverse perinatal outcome in patients screen-positive for neural tube defects and fetal down syndrome

An association between various abnormal mid-trimester maternal serum analyte values and adverse perinatal outcome has been reported. From an original sample of 14 857 women, we observed five women who were ‘screen-positive’ for both neural tube defects [maternal serum alpha-fetoprotein (MSAFP) ≥2·5 multiples of the median] and Down syndrome [risk ≥1/274 using MSAFP, maternal serum unconjugated oestriol (MSuE3), maternal serum human chorionic gonadotropin (MShCG), and maternal age]. The four patients who elected to undergo amniocentesis all demonstrated both normal karyotype and normal amniotic fluid AFP levels. All five cases were associated with intrauterine growth retardation (IUGR) and abnormal pregnancy outcomes. Two cases exhibiting severe IUGR on ultrasound examination were terminated at 19·1 and 21·2 weeks, respectively; the former also exhibited fetal calcifications and positive maternal serology for toxoplasmosis. In another case, fetal demise occurred at 36 weeks' gestation in a patient who had been treated for syphilis in the second trimester. Neither infection was confirmed in fetal tissue studies. Though resulting in live births, the remaining two cases required operative deliveries; emergency Caesarean sections for fetal distress were performed at 38 and 32 weeks, respectively, the latter case being associated with severe pre-eclampsia. We conclude that elevated mid-trimester MSAFP levels concurrent with maternal serum analyte values associated with increased risk for fetal Down syndrome may presage a poor perinatal outcome, particularly IUGR and possibly congenital infection.     

A targeted social marketing approach for community pro-environmental behavioural change

Community-level initiatives will play a key role in meeting greenhouse gas reduction targets. This paper examines the experience gained in applying a targeted social marketing approach to foster local-scale community pro-environmental behavioural change in the City of York, UK. This involved determining the neighbourhood carbon footprint, identifying residents that had access to appropriate infrastructure and were receptive to green issues. Six community teams were recruited from the selected neighbourhoods and provided with information, advice and mentoring on how to reduce their carbon footprint over a six-month period. A statistically significant reduction in carbon emissions was achieved. Each participant achieved a mean reduction in their carbon footprint of 2.0 tonnes of CO₂e/year. The largest reductions were achieved in the areas of shopping and home energy. In addition, it helped to foster community spirit. Based on the experience gained from implementing this approach, a cost-effective model of community engagement is proposed.     

Transmitter attachment and release methods for short-term shark and stingray tracking on coral reefs

This study details a simple and cost-effective means of attaching acoustic transmitters to coral reef sharks and stingrays, which potentially allows for retrieval and reuse on completion of tracks. Between 2008 and 2011, galvanised timed releases were trialled in both static field tests and on blacktip reef sharks Carcharhinus melanopterus, cowtail Pastinachus atrus, and porcupine Urogymnus asperrimus rays in Coral Bay (?23°08′41″, 113°45′53″), Western Australia. The timed releases remained attached to animals for the duration required for tracking and in four out of five deployments transmitters were recovered after release from the animals. The use of modified Rototags for sharks and stainless steel darts for stingrays allowed rapid and effective attachment to animals, with limited impact on their welfare in the short term. External attachment for short-term tracking of coral reef-associated elasmobranchs should be considered as a complementary option to internal placement of transmitters in animals either by surgery or by ingestion.     

Small-scale spatial and temporal genetic structure of the Atlantic sea scallop (Placopecten magellanicus) in the inshore Gulf of Maine revealed using AFLPs

Despite long planktonic durations, many species of broadcast spawning invertebrates exhibit genetic structure at small spatial and temporal scales. Amplified fragment length polymorphisms were used to assess genetic variation in the sea scallop, Placopecten magellanicus, among four inshore and one offshore location in the Gulf of Maine and temporal genetic variation among age classes of sea scallops at one site. Our results indicated that genetic structure for P. magellanicus exists on smaller spatial scales (tens to hundreds of kilometers) than expected given the 40-day planktonic larval period. In addition, genetic differences among age classes may be influenced by inter-annual differences in larval supply or reproductive success. Future genetic studies should sample multiple age classes prior to comparison among locations.     

Metabolism of nC11 fatty acid fed to Trichoderma koningii and Penicillium janthinellum II: Production of intracellular and extracellular lipids

Abstract

Little is known about the fungal metabolism of nC₁₀ and nC₁₁ fatty acids and their conversion into lipids. A mixed batch culture of soil fungi, T. koningii and P. janthinellum, was grown on undecanoic acid (UDA), a mixture of UDA and potato dextrose broth (UDA+PDB), and PDB alone to examine their metabolic conversion during growth. We quantified seven intracellular and extracellular lipid classes using Iatroscan thin-layer chromatography with flame ionization detection (TLC-FID). Gas chromatography with flame ionization detection (GC-FID) was used to quantify 42 individual fatty acids. Per 150 mL culture, the mixed fungal culture grown on UDA+PDB produced the highest amount of intracellular (531 mg) and extracellular (14.7 mg) lipids during the exponential phase. The content of total intracellular lipids represented 25% of the total biomass-carbon, or 10% of the total biomass dry weight produced. Fatty acids made up the largest class of intracellular lipids (457 mg/150 mL culture) and they were synthesized at a rate of 2.4 mg/h during the exponential phase, and decomposed at a rate of 1.8 mg/h during the stationary phase, when UDA+PDB was the carbon source. Palmitic acid (C_16:0), stearic acid (C_18:0), oleic acid (C_18:1), linoleic acid (C_18:2) and vaccenic acid (C_18:1) accounted for >80% of the total intracellular fatty acids. During exponential growth on UDA+PDB, hydrocarbons were the largest pool of all extracellular lipids (6.5 mg), and intracellularly they were synthesized at a rate of 64 μg/h. The mixed fungal species culture of T. koningii and P. janthinellum produced many lipids for potential use as industrial feedstocks or bioproducts in biorefineries.