Female Caught Research Articles

Spatio-temporal patterns and reproductive costs of abnormal clutches of female American lobster, Homarus americanus, in eastern Canada

Abstract Previous studies have documented female American lobster, Homarus americanus, carrying “abnormal clutches”, i.e. with eggs covering less than half of their abdomen. From 2011 to 2014, we worked alongside harvesters to quantify spatio-temporal patterns and reproductive costs of abnormal clutches among 138 738 egg-bearing female lobsters sampled from 193 homeports spread across eastern Canada. Females with abnormal clutches were ubiquitous, being found in 90% of homeports. Their incidence was, however, relatively low, averaging 6% across sampling times and locations. The incidence decreased between spawning and 7–9 months after spawning, potentially due to cases of complete brood failure caused by sperm limitation, and it then increased toward the end of the brooding period, potentially due to repeated catch and release of ovigerous females during the fishery. In most regions, small females were more likely to carry abnormal clutches than larger females. We estimated population-level egg loss between late oogenesis and hatching of embryos at 47–51%, with approximately half being associated with normal clutches and half with abnormal clutches and complete brood failure.

Size at maturity and molting probability across latitude in female Cancer pagurus

Edible crab, Cancer pagurus, is a valuable North Atlantic fishery resource distributed from Morocco to northern Norway, covering a wide range of temperatures and other oceanographic variables. Knowledge on how local environmental conditions affect life history traits like maturity and growth in this species is however lacking, despite its importance in science-based management. Through analyses of field data and fishers’ reports from different areas along the west coast of Norway (between 59°N and 69°N), latitudinal differences in size at onset of sexual maturity and molting probabilities of female C. pagurus were investigated. The size at which 50% of crabs were found to be mature (CW50) did not differ between areas and was consistent with historical investigations, i.e. overall CW50: 112.3 mm, and CW50 for each area/year between 108 and 117 mm. Generalized additive modelling was used to predict probability of molting (occurrence of soft crabs) during late summer/autumn, with ‘area’ as a categorical variable, and ‘day of year’ and crab size as continuous non-linear predictors. The predictor variables had low explanatory power (16.4% deviance explained by full model), demonstrating the complexity of the process regulating molting. However, frequency of molting decreases and peak periods of molting occur later at higher latitudes, suggesting that lower temperatures have an impeding effect on growth in northern populations. Overall, our findings suggest that current minimum legal catch sizes for crabs in Norwegian waters are sufficient to restrict the catch of immature females, but that crabs in different geographical regions appear to be variably tolerant to fishing pressure following differences in growth.

Pengembangan Perikanan Lobster di Provinsi Lampung

Perikanan lobster di Provinsi Lampung telah dilakukan sejak tahun 1980-an dengan kegiatan perikanan tangkap yang dilakukan oleh nelayan dan dijual pada pedagang pengumpul lokal. Studi tentang perikanan lobster di Provinsi Lampung masih terbatas, sehingga masih banyak fakta secara biologis dan sosial ekonomi dapat dikembangkan yang tujuannya dapat membantu pembangunan perikanan lobster dimasa mendatang. Penelitian dilakukan dengan survei pada nelayan dan pedagang pengumpul lobster di Kabupaten Pesisir Barat pada Agustus sampai dengan Desember 2016. Hasil survei menunjukkan bahwa kegiatan penangkapan lobster tidak mengalami perkembangan yang pesat tetapi menunjukkan penurunan volume tangkap dengan makin berkurangnya jenis lobster yang berharga tinggi dan ukuran yang semakin kecil. Perlu dikembangkan perikanan lobster tidak hanya perikanan tangkap yang perlu dibatasi kuota penangkapannya tetapi juga perikanan budidaya untuk mengantisipasi peningkatan konsumsi dan perlindungan stok alam dengan pelepasliaran yang berpijak pada bidang biologi perikanan. Peta jalan kegiatan penelitian perikanan tangkap dan budidaya lobster yang dapat dikembangkan pada jangka pendek dan jangka panjang telah disusun agar menjadi rujukan oleh masyarakat luas untuk pembangunan perikanan lobster lebih khusus lagi pada kajian fisiologi reproduksi. Terkait dengan pelarangan penangkapan lobster ukuran kecil dan lobster bertelur, penjualan puerulus dan lobster konsumsi juga dibahas dalam tulisan ini.

Female Responses to Synthetic Pheromone and Plant Compounds in Agriotes brevis Candeze (Coleoptera: Elateridae)

Traps baited with synthetic pheromone components of Agriotes brevis [geranyl butanoate + (E,E)-farnesyl butanoate] captured significantly higher numbers of not only male, but also female beetles, compared to unbaited controls. Catches of both sexes showed a clear positive relationship with increasing doses. In electroantennogram tests, antennal responses of females and males to a number of known Agriotes pheromone components, identified from pheromone glands, showed a similar trend, with geranyl butanoate eliciting the strongest responses. This suggests that the female and male A. brevis antennae are similar with respect to the perception of pheromone compounds, and female beetles have the sensory capabilities to perceive the pheromone components which they produce. Addition of the plant-derived compounds (Z)-3-hexenyl acetate, methyl benzoate, (Z)-3-hexenol and methyl salicylate (identified earlier from foliage as attractive for A. brevis) to the synthetic pheromone significantly increased catches. All the above results suggest that geranyl butanoate and (E,E)-farnesyl butanoate are constituents of an aggregation pheromone of A. brevis, in contrast to the general view of click beetle pheromones being “classical” sex pheromones. These findings could be useful for more precise monitoring and forecasting of damage, based on female catches.

Aspects of oophagyin Alopias vulpinus (Elasmobranchii, Alopiidae) in the southern Brazil

Oophagy of the genus Alopiaswas described by several authors nevertheless this paper presents some new aspects of the oophagy of A Vulpinus Four embryos of A vulpinus being three males with total lengths of cm kg cm kg and cm kg and a female with cm kg were obtained from a female caught by Brazilian artisanal fishing using in shore gillnet at a depth of m off Peruibe City Sao Paulo State Brazil in November Five oocytes were integer and the size ranged from to mm This study found clear evidence that embryos of A vulpinus ingest the whole oocyte No traces of smaller siblings were found in the four embryos stomachs so the species probably do not perform adelphophagy

The first record of diprosopus tetrophthalmus in the South Atlantic Ocean: The case of Prionace glauca (Elasmobranchii: Carcharhiniformes: Carcharhinidae) in Brazil

The majority of morphological abnormalities reported for elasmobranchs are cases of bicephalia. This contribution describes the third confirmed case worldwide and the first in the South Atlantic of diprosopus tetrophthalmus (craniofacial duplication) in a foetus of blue shark, Prionace glauca (Linnaeus, 1758), from a female caught off the Brazilian coast (26°36′11′′S, 45°56′00′′W) in July 2007. The specimen is described and compared to normal specimens from the same size and to another one with similar deformities from Chile. The embryo is smaller than a normal embryo, with deformities in the skull, head muscles and curvature of the vertebral column.

Evaluating the Use of Phenylacetonitrile Plus Acetic Acid to MonitorPandemis pyrusanaandCydia pomonella(Lepidoptera: Tortricidae) in Apple

Recent studies have demonstrated that key herbivore-induced foliage volatiles from apple, Malus domestica Borkhausen (Rosaceae), can be attractive to conspecific adult male and female tortricid leafrollers when used together with acetic acid lures. Our study reported here was conducted in Washington State during 2013–2014 and assessed the attractiveness of both sexes of the leafroller, Pandemis pyrusana Kearfott (Lepidoptera: Tortricidae), to blends of acetic acid with phenylacetonitrile. Interestingly, traps baited with phenylacetonitrile plus acetic acid caught significantly more males, females, and total moths than the number of males caught in traps baited with a commercial sex pheromone lure. The evaporation rate of the acetic acid co-lure was shown to be an important factor affecting catches of P. pyrusana with phenylacetonitrile. Adding phenylacetonitrile to traps baited with pear ester, ethyl (E, Z)-2,4-decadienoate and acetic acid significantly reduced both total and female moth catches of codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae). However, neither C. pomonella nor P. pyrusana catch were impacted when phenylacetonitrile and acetic acid were added to traps baited with pear ester plus (E, E)-8,10-dodecadien-1-ol, the sex pheromone of codling moth. These results support our broader work to develop lures to improve monitoring and management of a number of tortricid pests attacking horticultural crops worldwide. Resumen Estudios recientes han demostrado que volatiles foliares claves inducidos por herbivoros en manzano, Malus domestica Borkhausen (Rosaceae), pueden ser atractivos para hembras y machos adultos conspecificos de enrolladores tortricidos cuando se usan junto con cebos de acido acetico. Nuestro estudio, descrito aqui, se llevo a cabo en el estado de Washington durante 2013-2014 evaluando la atraccion de ambos sexos del enrollador, Pandemis pyrusana Kearfott (Lepidoptera: Tortricidae), a mezclas de acido acetico con fenilacetonitrilo. Curiosamente, las trampas cebadas con fenilacetonitrilo y acido acetico capturaron significativamente mas machos, hembras y polillas totales que el numero de machos atrapados en trampas provistas de un cebo comercial de feromonas sexuales. Demostrandose que la tasa de evaporacion del co-atractante de acido acetico era un factor importante que afectaba las capturas de P. pyrusana con fenilacetonitrilo. La adicion de fenilacetonitrilo a las trampas cebadas con ester de pera, etil (E, Z) -2,4- decadienoato y acido acetico redujo significativamente tanto la captura total como la de hembras de polilla de la manzana, Cydiapomonella (L.) (Lepidoptera: Tortricidae). Sin embargo, ni la captura de C. pomonella ni la de P. pyrusana se vieron afectadas cuando se anadieron fenilacetonitrilo y acido acetico a las trampas cebadas con ester de pera y (E, E)-8,10-dodecadien-1-ol, feromona sexual de polilla de la manzana. Estos resultados respaldan nuestro trabajo mas amplio para desarrollar cebos que mejoren el monitoreo y manejo de varias especies de plagas de la familia Torticididae, que atacan cultivos horticolas en todo el mundo.View this article in BioOne

Possible antagonism of (Z)‐2‐hexenyl (E)‐3‐hexenoate against the attractiveness of (E)‐2‐hexenyl (Z)‐3‐hexenoate to Ooencyrtus nezarae (Hymenoptera: Encyrtidae)

AbstractOoencyrtus nezarae (Hymenoptera: Encyrtidae) is an egg parasitoid of bean bug Riptortus pedestris (Hemiptera: Alydidae) which is a major pest of beans. Females of O. nezarae are attracted to (E)‐2‐hexenyl (Z)‐3‐hexenoate (EZ), one of the components of aggregation pheromone of R. pedestris. Effects of three isomers (ZE, EE and ZZ) of EZ on the attractiveness of O. nezarae were tested using electroantennography (EAG) and field bioassays. EAG analyses revealed that the response of O. nezarae to ZE was significantly higher than those to air, hexane and two other isomers, even though the response was lower than that to EZ. ZE affected the attractiveness of EZ dose‐dependently in the field. Addition of ZE (100 mg) to EZ (10 mg) caused a significant reduction in the catches of O. nezarae females. Single or binary addition of two other isomers (EE and ZZ) to EZ could not decrease or increase significantly the number of O. nezarae catches of EZ. Even though addition of ZZ (10, 50 or 100 mg) to EZ (10 mg) caused dose‐dependent reduction in the number of O. nezarae female catches, the reductions were not significantly different from that of EZ. EZ and its three isomers were not attractive to O. nezarae males at all.

Predicting Nut Damage at Harvest Using Different in-Season Density Estimates of Amyelois Transitella: Analysis of Data from Commercial Almond Production.

Despite decades of research on management tactics for the navel orangeworm, Amyelois transitella (Walker) (Lepidoptera: Pyralidae), on almonds, we still do not have an established means of using in-season pest-density estimates to predict damage to nuts at harvest. As a result, hull-split pesticide applications, although timed carefully to coincide with navel orangeworm oviposition and with crop vulnerability, are not tied to pest densities-thus falling short of our goals under modern pest management. Here we use an ecoinformatics approach, analyzing a pre-existing data set collected in commercial almond production in California, to ask: 1) are navel orangeworm density estimates obtained using different sampling methods in strong agreement with one another? and 2) can we use either single density estimates or combinations of density estimates to explain variation in nutmeat damage at harvest? We find that correlations between density estimates of navel orangeworm made over a single growing season are often weak, and suggest that density estimates taken closer to the time of harvest (catches of adult females between hull split and harvest; infestation of early-split nuts) may be most useful for predicting damage at harvest. Single-density estimates explained ≤39.1% of variation in harvest damage, whereas a combination of predictors explained 51.5% of the total variance in nutmeat damage at harvest. Our results suggest that density estimates taken just prior to harvest may, with refinement, be usable within a predictive framework to guide late-season control decisions.

Development of kairomone-based lures and traps targeting Spilonota ocellana (Lepidoptera: Tortricidae) in apple orchards treated with sex pheromones

AbstractSpilonota ocellana (Denis and Schiffermüller) (Lepidoptera: Tortricidae) can be a serious pest of organic apples (Malus domestica Borkhausen (Rosaceae)) in British Columbia, Canada. Recent discovery that S. ocellana moths are attracted by a lure combining acetic acid (AA) and benzyl nitrile (BN), identified as a caterpillar-induced apple leaf volatile, provides an opportunity to develop bisexual mass-trapping or monitoring systems. Sticky white delta traps baited with benzyl nitrile (10 mg/red rubber septum) and an acetic-acid co-lure (3 mL AA/3-mm open 8-mL vial) caught significantly more moths than either component alone. Acetic-acid co-lures were weakly attractive but benzyl-nitrile-loaded septa were not attractive. Moth catches with AA+BN lures were unaffected by the size and type of rubber septum used to release benzyl nitrile, but catches increased with increasing loads of benzyl nitrile. Male and total moth catches were maximised using membrane release devices loaded with a mixture of benzyl nitrile and a second caterpillar-induced volatile, 2-phenylethanol (PET), in combination with an acetic-acid co-lure (AA+BN-PET). Female catches with AA+BN-PET and AA+BN lures were equivalent. Placing AA+BN lures in traps baited with female sex pheromone lures reduced male catches, but female catches were unchanged. When sticky liners were replaced weekly, white delta traps baited with AA+BN lures caught more moths than similarly baited white Multipher®-I bucket traps, or transparent UnitrapsTM. Multipher-I traps with a propylene glycol killing agent (250 mL) caught more moths than those with Vapona insecticide strips. In apple orchards treated with mating disruption sex pheromones, traps baited with AA+BN caught slightly more total moths than traps baited with sex pheromone. Weekly, total male+female moth catches with either AA+BN or sex pheromone lures showed similar seasonal patterns in both untreated and pheromone-disrupted orchards, respectively. Long-lasting release devices and an organic killing agent are needed to develop certified organic mass-trapping technologies for management of S. ocellana with the AA+BN kairomone.

Ultrastructure and morphometry of the egg of Psorophora albipes (Theobald, 1907) (Diptera: Culicidae)

The eggs of Psorophora albipes were studied using scanning electron microscopy (SEM) and described based on a morphometric analysis of the main structures observed. We used eggs from a female caught in the Poço das Antas Biological Reserve (REBIO-PA), located in the municipality of Silva Jardim, State of Rio de Janeiro, Brazil. The eggs have an elliptical outline with a mean length of 538.67 ± 69.89 μm and width of 157.66 ± 23.12 μm and a mean egg index of 3.42 ± 0.07 μm. The external coating of the eggs is regular, with elongated chorionic cells that vary in size, with a mean length of 13.02 µm and mean width of 6.47 µm. The cells mostly have a pentagonal shape, but some have an elliptical shape. The micropylar disc has a mean diameter of 19.8 μm, it has small irregularities in its outline, excavations at the edge with the center slightly raised and a micropyle with a diameter of 2.36 μm. Complete knowledge of the egg morphology of species through SEM is useful in correlating its fine structure with consistent non-discernible differences observed under a stereoscopic microscope, and can aid in species discrimination. SEM allows the construction of identification keys for mosquito eggs that should be useful for studies involving eggs recovered from ovitraps or debris/soil samples.

Attraction range of a sex pheromone trap for the damson‐hop aphidPhorodon humuli(Hemiptera:Aphididae)

AbstractThe attraction range of olfactory response by winged female gynoparae (autumn migrants that give birth to oviparae, the sexual females) and male damson–hop aphidsPhorodon humuli(Schrank) is investigated in field experiments over 2 years by analyzing the spatial patterns of catches in concentric circles of yellow‐painted traps (60 in total) around a central trap releasing the species' sex pheromone, (1RS,7S,7aS)‐nepetalactol. Males are more likely than females to be found in the central trap, with 65.6% of the 1824 males caught there compared with 11.2% of 1346 females. Both morphs are more numerous in traps axial with the mean wind direction and centred on the pheromone‐release trap than at other angles. Males are approximately five‐fold more numerous in traps downwind than at similar distances upwind of the pheromone, showing that its presence stimulates landing. For males, the estimated active space of the lure extends 6 m downwind. Catches of females are equally numerous up and downwind of the pheromone lure because females orienting on the axis of the pheromone source continue to respond to visual cues in their flight path if they overshoot the olfactory one. For females, the active space of a pheromone lure is less than 2 m downwind. It is unimportant for either morph whether the pheromone‐release trap is yellow or transparent. In these experiments, both morphs orient with, track and probably arrive in the pheromone source trap from at least 26 m, the distance to the nearest aphid‐infested hops.

Crayfish in central and southern Ukraine with special focus on populations of indigenous crayfish Astacus pachypus (Rathke, 1837) and their conservation needs

Abstract The thick‐clawed crayfish (Astacus pachypus Rathke, 1837) is the least studied indigenous crayfish species in Europe. Information about its distribution and biology is out of date by more than 15 years. This study identified 94 localities with potential occurrence of thick‐clawed crayfish in eight southern and central regions of Ukraine, using questionnaire and literature analysis. Based on the information obtained, a field survey was conducted to examine and confirm the current distribution and abundance of crayfish species and evaluate basic water quality and habitat characteristics in each locality. Details of density, sex ratio in the catches, health and moulting condition, threat level and water quality were identified for each population of A. pachypus. Only four populations of this species were found, in lower parts of the Dnieper River, co‐occurring with Astacus leptodactylus Eschscholtz, in Kakhovka reservoir near Vesele village, two sites on the Dnieper River near Nova Kakhovka town and near Prydniprovske village, and one locality on the Dnieper's tributary – the Ingulec River near Sadove village. Populations of thick‐clawed crayfish at three sites had low crayfish densities of 0.3–0.4 crayfish m−2 or catch efficiency 0.2 crayfish per trap night. Only one locality on the Dnieper River, close to Nova Khakovka, had a stronger population with higher density (1.7 crayfish m−2). Healthy thick‐clawed crayfish inhabit larger water bodies with stable environments and good water quality. Female catch per unit effort was lower, and they had a higher percentage of chelae injuries compared with males. All of the identified thick‐clawed crayfish populations are exploited by uncontrolled fishing for consumption and there is an urgent need for conservation of both the crayfish and their habitat.

Efficacy of trapping systems for monitoring of Afrotropical fruit flies

AbstractThe efficacy of different attractant trap combinations for monitoring of Afrotropical fruit flies was evaluated in commercial fruit production areas and natural areas in the northern parts of South Africa. Five food‐based attractants: three‐component Biolure, a combination of ammonium acetate and trimethylamine, a combination of ammonium acetate and putrescine, torula yeast and Questlure, were evaluated in McPhail‐type traps. Two male lures targeting Ceratitis species: EGO Pherolure and trimedlure, were evaluated in Sensus bucket traps. Three male lures targeting Dacine fruit flies: methyl eugenol, cue lure and zingerone, were evaluated in Moroccan bucket traps. The three‐component Biolure was among the most effective food‐based attractant for females of Ceratitis capitata, C. rosa (R1 and R2), C. cosyra and Bactrocera dorsalis. EGO Pherolure attracted a wider range of Ceratitis species than trimedlure but was equally as effective as trimedlure for males of C. capitata and C. rosa (R1 and R2). Dacine flies were specific in their responses to male lures. Bactrocera dorsalis males responded mainly to methyl eugenol. Males of Dacus species responded to either cue lure or zingerone. Zingerone attracted two cucurbit‐infesting Dacus species: D. frontalis and D. durbanensis. For B. dorsalis, C. capitata and C. cosyra in commercial fruit production areas, patterns of female catches in traps containing food‐based attractants were different to patterns of male catches in male lure‐based traps. Implications of these trapping results are discussed.

Abundance and Morphometric Relationships of Amazon Shrimp - Macrobrachium amazonicum (Heller 1862) (Decapoda, Palaemonidae) - In an Amazon Estuary - North Coast of Brazil

From Macrobrachium amazonicum ( Heller, 1862 ) (Decapoda, Palaemonidae) abundance in monthly collections in the Amazon estuary and on Mosqueiro Island (State of Para, Brazil) between April 2006 and August 2007, we verified that the site mentioned is favorable to the development of the species, since there is a significant number of young and adults specimens throughout the year, whose abundance is significantly higher in the dry season. Icoaraci was the site of great contribution in the total of specimens caught, relating this productivity to the large amount of organic matter in suspension. In this study, we found the largest M. amazonicum specimen ever collected, comparing to those mentioned by available scientific literature. The individual was a female caught on Combu Island with 44.72 mm carapace length or 18.45 cm total length. Relations of body mass (g) vs. carapace length (mm) for males, females and sexes together had negative allometry, which can be associated to the gonadal maturation cycle of the species. All other morphometric relationships showed positive allometry. Keywords . carapace; bio-ecology; population dynamics.

The largest relative testis size among primates and aseasonal reproduction in a nocturnal lemur, Mirza zaza.

Testis size is an indirect indicator of a species' mating system, along with sexual size and canine dimorphism, existence and usage of mating and advertisement calls as well as the spatial distribution of males and females ready to mate in solitary species. Upon its recent discovery, the northern giant mouse lemur Mirza zaza was suggested to have a polygynandrous mating system and to exhibit seasonal breeding. We tested these predictions in a field study in Sahamalaza National Park, NW Madagascar. We caught 12 M. zaza, before and during the suggested mating period and obtained standard field morphometric measurements, including testes size. We show that M. zaza has the highest relative testis volume among primates, indicating strong sperm competition and polygynandrous mating. In addition, based on inferred age of captured animals, observed mating behavior, a female caught in met-estrus and data from captivity, we suggest M. zaza to be one of the few lemurs that breed aseasonally. Future field work on this endangered species is required to illuminate the causes and consequences of intense promiscuity and aseasonal breeding despite strong habitat seasonality, which distinguish M. zaza from most other nocturnal lemurs.

Artificial warthog burrows used to sample adult and immature tsetse (Glossina spp) in the Zambezi Valley of Zimbabwe.

BackgroundThe biology of adult tsetse (Glossina spp), vectors of trypanosomiasis in Africa, has been extensively studied – but little is known about larviposition in the field.Methodology/Principal FindingsIn September-November 1998, in the hot-dry season in Zimbabwe’s Zambezi Valley, we used artificial warthog burrows to capture adult females as they deposited larvae. Females were subjected to ovarian dissection and were defined as perinatal flies, assumed to have entered burrows to larviposit, if oocyte sizes indicated >95% pregnancy completion. Perinatal flies were defined as full-term pregnant if there was a late third instar larva in utero, or postpartum if the uterus was empty. All other females were defined as pre-full-term pregnant (pre-FT). Of 845 G. m. morsitans captured, 91% (765) were female and 295/724 (41%) of females dissected were perinatal flies. By contrast, of 2805 G. pallidipes captured only 71% (2003) were female and only 33% (596/1825) of females were perinatal. Among all perinatal females 67% (596/891) were G. pallidipes. Conversely, in burrows not fitted with traps – such that flies were free to come and go – 1834 (59%) of pupae deposited were G. m. morsitans and only 1297 (41%) were G. pallidipes. Thus, while more full-term pregnant G. pallidipes enter burrows, greater proportions of G. m. morsitans larviposit in them, reflecting a greater discrimination among G. pallidipes in choosing larviposition sites. Catches of males and pre-FT females increased strongly with temperatures above 32°C, indicating that these flies used burrows as refuges from high ambient temperatures. Conversely, catches of perinatal females changed little with maximum temperature but declined from late September through November: females may anticipate that burrows will be inundated during the forthcoming wet season. Ovarian age distributions of perinatal and pre-FT females were similar, consistent with all ages of females larvipositing in burrows with similar probability.Conclusions/SignificanceArtificial warthog burrows provide a novel method for collecting tsetse pupae, studying tsetse behaviour at larviposition, assessing the physiological status of female tsetse and their larvae, and of improving understanding of the physiological dynamics of terminal pregnancy, and population dynamics generally, with a view to improving methods of trypanosomiasis control.

Modeling codling moth (Lepidoptera: Tortricidae) phenology and predicting egg hatch in apple orchards of the Maule Region, Chile

Studies were conducted in the Maule Region to characterize the phenology of the codling moth, Cydia pomonella (L.) The Predictive Extension Timing Estimator (PETE) and a logistic phenological model were validated with eight data sets of cumulative moth catches in sex pheromone (PH) and kairomone-baited traps and the cumulative occurrence of fruit injuries from apple (Malus domestica Borkh.) orchards during the 2009-2011 seasons. Second, the start of egg hatch was predicted from the first sustained male and female moth catches (biofix) in traps baited with pear ester (PE), PE+acetic acid (AA), PE+PH, and PH alone. Both phenological models fit data well except that the logistic provided a better fit than the PETE model of the phenology of egg hatch of the codling moth in the first generation, with a difference of 11 d between models in the prediction of 50% egg hatch. No significant difference was found between biofix dates established for males using either PH or PE+PH lures or for the biofix date based on female catches with PE+AA or PH+PE. The biofix established with the sustained female catch occurred nearly 11 d later than the male-based biofix. The use of a female biofix provided on average a 4-d improvement in the prediction of first egg hatch compared with the traditional use of a male biofix, but this difference was not significant. The use of PE+AA lures increased the proportion of cases when a female-based biofix could be established compared with the use of the PH+PE lure.

Field Abundance Patterns and Odor-Mediated Host Choice by Clover Seed Weevils, Apion fulvipes and Apion trifolii (Coleoptera: Apionidae).

The clover seed weevils Apion fulvipes Geoffroy, 1785 and Apion trifolii L., 1768 (Coleoptera: Apionidae) cause major losses to seed production of white clover (Trifolium repens L.) and red clover (Trifolium pratense L.), respectively. Clover is important as animal forage and an alternative to inorganic fertilizers. Because clover is mainly pollinated by bees, the use of insecticides in management of these weevils is discouraged. To gain basic knowledge for development of alternative management strategies, we investigated weevil field abundance over two growing seasons, as well as feeding and olfactory host preferences by A. fulvipes and A. trifolii. Field trap catches in southern Sweden revealed that white clover was dominated by A. fulvipes and red clover by A. trifolii. For both weevil species, female catches were positively correlated to the number of clover buds and flowers in the field. In feeding and olfactory bioassays, females of A. fulvipes and A. trifolii showed a preference for T. repens and T. pratense, respectively. However, the feeding preference was lost when the antennae were removed, indicating a significant role of olfaction in host choice. Male weevils of both species did not show clear olfactory or feeding preferences for host plant species. The field study and laboratory bioassays demonstrate that, at least for female weevils, olfaction is important for selection of host plants. We discuss these novel results in the context of managing these important pests of clover by exploiting olfaction and behavioral attraction to host plant volatiles.

Birth sex ratio, infant mortality and rearing type in captive western lowland gorillas

One of the main challenges for the successful captive breeding programme for the western lowland gorilla is the management of males surplus to the population. In addition, infant mortality and rearing type can have a large effect on the development of the population. A better understanding of factors influencing sex ratio, infant mortality and rearing could be advantageous for the management of the captive population. We analysed 1286 births from 378 different dams living in zoos participating in the international breeding programme. Our results show that there is a trend for a male-biased sex ratio with increasing maternal age, but the relationship is not significant and we conclude that limiting reproduction in older females would not sufficiently reduce the surplus of males to warrant the possible negative effects on population genetics and social development. None of the following factors had a significant effect on infant mortality within 30 days after birth: maternal age at conception, birth order, rearing type of the mother, sex of the offspring, survivorship of the previous offspring or population. However, there was a significant decrease in infant mortality over the years, probably reflecting improved captive husbandry practices. Infants born to a hand-reared female had to be hand reared significantly more often as opposed to those of parent-reared and wild-caught females. The ratio of hand-reared offspring showed a significant decrease throughout the study period, showing again the positive results of current management strategies. The study confirms that over the years the management of gorillas in captivity has been considerably improved. Selective breeding with young females will not resolve the problem of surplus males and other solutions will have to be investigated. Neither maternal age at conception, nor birth order, rearing type of the mother, sex of the offspring, survivorship of the previous offspring or population did have a significant effect on infant mortality within 30 days after birth. However, there was a significant decrease of infant mortality through the years, probably reflecting improved captive husbandry practices. Infants born to a hand reared female had to be hand reared significantly more often as opposed to those of parent reared and wild caught females. The ratio of hand reared offspring showed a significant decrease throughout the study period, showing again the positive results of current management strategies. The study confirms that through the years the management of gorillas in captivity has been improved considerably. Selective breeding with young females will not resolve the problem of surplus males and other solutions will have to be investigated.