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The article discusses a study aimed at identifying based on geolocators the migration routes, breeding quarters and post-nuptial moulting areas of long-billed Purple Sandpipers that can be found during winter and spring in northern Scotland and western Ireland. Topics include the effect of the geolocators on the birds, the accuracy of geolocations, and the timing of migration. It concludes that bulk of the wintering Purple Sandpipers start from Canada, particularly in the Hudson Strait region.

Cherryslug, Caliroa cerasi, is an important pest of organic pear production in New Zealand. It is reported to have two generations per year and cause severe leaf damage, particularly through the feeding of second generation larvae in mid to late-summer. This insect has been little studied in Central Otago. Adult cherryslugs were monitored with sticky traps in a block of ‘Taylor's Gold’ pears in the summers of 1999–2001 and the catches were used to assist in timing the single application each season of a range of organically-acceptable insecticides in randomized block experiments which included untreated control trees. The insecticides were: 1999–2000, ryanodine, lime sulphur, kaolin in January, kaolin in February; 2000–01, pyrethrum +mineral oil, lime sulphur, neem extract, kaolin in January. Efficacy was assessed using pre- and post-treatment larval counts and leaf damage. The impact of pre-treatment larval density on post-treatment efficacy was investigated to determine a preliminary spray threshold, specifically for pyrethrum+mineral oil. The adult monitoring indicated that cherryslug is univoltine in Central Otago, with the first adults appearing at the end of December. All the insecticides tested significantly reduced damage from cherryslug larvae and, if registered, could be used by organic growers. In both seasons, kaolin application in January, which targeted the adult cherryslugs, was more effective than all the other products, which were applied in February against the larvae. On the other hand, kaolin applied in February 2000 resulted in greater cherryslug damage than occurred with the other insecticides applied at that time. Larval density had a significant effect on the efficacy of pyrethrum+mineral oil, particularly when >10 larvae could be counted per minute on the trees before treatment. The implications of this result and the comparative efficacy of the different treatments are discussed in relation to organic pear production in Otago. [ABSTRACT FROM PUBLISHER]

Oystershell scale, Diaspidiotus ostreaeformis, is a pest of fruit crops in Otago and Canterbury that is well controlled within orchards but becomes a problem at harvest due to invasion from external host trees. Its major pest status on export crops comes from its being indistinguishable on harvested fruit from the critical quarantine pest San Jose scale Diaspidiotus perniciosus. Oystershell scale has a wide host range which includes trees frequently used as orchard shelter. The distribution of oystershell scale in apples adjacent to an infested shelter belt was investigated in Otago in 1995-96. Apple infestation was >90% next to the shelter and declined linearly to <1% 64 m away. The slope of this linear regression was similar on four cultivars of apple but infestation increased substantially from early- to late-harvested cultivars. The phenology of oystershell scale on apples in 1998-2000 was found to precede that on a range of other hosts, which extended the period of risk of fruit infestation by crawlers from December to April each year. Experiments were conducted in 1999-2000 on control of oystershell scale on a range of infested shelter trees using a vertical boom sprayer. Sprays timed for control of adult males and females in spring provided only a short-term reduction of winged males in sticky traps and failed to reduce crawler production and dispersal as measured by sticky bands and traps on tree branches. On the other hand, sprays timed for control of crawlers in mid-summer were effective in greatly reducing catches of crawlers. The options for management of oystershell scale on alternative hosts, particularly shelter, are discussed in relation to phenology, crop invasion by crawlers, host resistance and spraying. [ABSTRACT FROM AUTHOR]

Woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann), and its natural enemies were monitored from 1994 to 2000 on apples at Clyde, Central Otago, New Zealand during the transition from conventional fruit production (CFP), which used broad spectrum insecticides, to integrated fruit production (IFP), which was based on selective insecticides. Populations were compared in orchard blocks under three management regimes: CFP; transition to IFP; and a biological fruit production (BFP) programme which complied with BioGro® organic certification. WAA remained at very low levels in the CFP programme, because of insecticides, and in the BFP programme, primarily because of natural enemies. Transition to IFP was accompanied by a surge in WAA and a slow colonization by natural enemies which took at least four years to reduce the aphid population to acceptable levels. The principal natural enemy that achieved this was the parasitoid Aphelinus mali (Haldemann), assisted by predators whose contribution remained obscure, including the brown lacewing Micromus tasmaniae (Walker) and the European earwig Forficula auricularia L. A single annual application of lufenuron within the IFP programme was not detrimental to any of these natural enemies, although further research is needed to confirm its lack of impact on the lacewing. Lufenuron reduced arboreal predator diversity, as measured by the Shannon-Wiener index, and this was in part due to decline in the populations of the generalist predator Orius vicinus (Ribaut) and the coccinellid mite predator Stethorus bifidus Kapur. Pirimicarb was an effective selective aphicide for integration with the action of the natural enemies of WAA, but a substitute is required, as its use is no longer permitted on export crops. The implications of these findings for the management of WAA in IFP are discussed. [ABSTRACT FROM AUTHOR]

The survival and development rate of Ctenopseustis obliquana (Walker) (Lepidoptera: Tortricidae) larvae, and weight of pupae were measured on detached mature leaves of two apple (Malus domestica Borkh.) progenies derived from the resistant (R) parent 'Prima' crossed with the susceptible (S) cultivars 'Liberty' (n = 44) and 'Red Delicious' (n = 35). The R:S ratio in both these modified backcross families did not differ significantly from the 1:1 expected in the case of monogenic resistance, carried in a heterozygous condition in the resistant parent. The survival to pupation on the individual seedlings was either zero/very low (R) or high (S). With all resistant seedlings being heterozygous, this indicates that the resistance allele shows complete dominance over the susceptible allele. We have named this putative gene Cob1. The expression of the resistance was found to be influenced by both the colony of C. obliquana used and the time of the season when resistance was assessed. In a separate experiment with another tortricid, there was no survival of lanotortrix octoDugdale larvae on the apple cultivar 'Prima' and high survival on the cultivars 'Liberty' and 'Red Delicious'. The similarity of the responses of the two leafroller species to these cultivars, and other published evidence concerning Planotortrix excessana (Walker) and Ctenopseustis herana(Felder and Rogerhofer), suggest that the resistance discovered to C. obliquanamay be effective against all four endemic tortricid species. The implications of these findings for apple breeding and leafroller control in New Zealand are discussed. [ABSTRACT FROM AUTHOR]

The article provides evidence that majority of Scottish- and Irish-wintering Purple sandpipers migrate to Arctic Canada to breed. Topics discussed include the trans-Atlantic migration of the birds in early winter, the median arrival date for all birds in Greenland, and the geo-locations of the birds prior to departure from northern Scotland and Ireland.

Recent studies have suggested that protected areas often fail to conserve target species. However, the efficacy of terrestrial protected areas is difficult to measure, especially for highly vagile species like migratory birds that may move between protected and unprotected areas throughout their lives. Here, we use a 30-y dataset of detailed demographic data from a migratory waterbird, the Whooper swan ( Cygnus cygnus ), to assess the value of nature reserves (NRs). We assess how demographic rates vary at sites with varying levels of protection and how they are influenced by movements between sites. Swans had a lower breeding probability when wintering inside NRs than outside but better survival for all age classes, generating a 30-fold higher annual growth rate within NRs. There was also a net movement of individuals from NRs to non-NRs. By combining these demographic rates and estimates of movement (into and out of NRs) into population projection models, we show that the NRs should help to double the population of swans wintering in the United Kingdom by 2030. These results highlight the major effect that spatial management can have on species conservation, even when the areas protected are relatively small and only used during short periods of the life cycle.

Environmental heterogeneity shapes the uneven distribution of resources available to foragers, and is ubiquitous in nature. Optimal foraging theory predicts that an animal's ability to exploit resource patches is key to foraging success. However, the potential fitness costs and benefits of foraging in a heterogeneous environment are difficult to measure empirically. Heterogeneity may provide higher-quality foraging opportunities, or alternatively could increase the cost of resource acquisition because of reduced patch density or increased competition. Here, we study the influence of physical environmental heterogeneity on behaviour and reproductive success of black-legged kittiwakes, Rissa tridactyla. From GPS tracking data at 15 colonies throughout their British and Irish range, we found that environments that were physically more heterogeneous were associated with longer trip duration, more time spent foraging while away from the colony, increased overlap of foraging areas between individuals and lower breeding success. These results suggest that there is greater competition between individuals for finite resources in more heterogeneous environments, which comes at a cost to reproduction. Resource hotspots are often considered beneficial, as individuals can learn to exploit them if sufficiently predictable. However, we demonstrate here that such fitness gains can be countered by greater competition in more heterogeneous environments.

The manner in which patterns of variation and interactions among demographic rates contribute to population growth rate (λ) is key to understanding how animal populations will respond to changing climatic conditions. Migratory species are likely to be particularly sensitive to climatic conditions as they experience a range of different environments throughout their annual cycle. However, few studies have provided fully integrated demographic analyses of migratory populations in response to changing climatic conditions. Here, we employed integrated population models to demonstrate that the environmental conditions experienced during a short but critical period play a central role in the demography of a long-distance migrant, the light-bellied Brent goose (Branta bernicla hrota). Female survival was positively associated with June North Atlantic Oscillation (NAO) values, whereas male survival was not. In contrast, breeding productivity was negatively associated with June NAO, suggesting a trade-off between female survival and reproductive success. Both adult female and adult male survival showed low temporal variation, whereas there was high temporal variation in recruitment and breeding productivity. In addition, while annual population growth was positively correlated with annual breeding productivity, a sensitivity analysis revealed that population growth was most sensitive to changes in adult survival. Our results demonstrate that the environmental conditions experienced during a relatively short-time window at the start of the breeding season play a critical role in shaping the demography of a long-distant Arctic migrant. Crucially, different demographic rates responded in opposing directions to climatic variation, emphasising the need for integrated analysis of multiple demographic traits when understanding population dynamics., (© 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.)

Background: New Zealand flower thrips (NZFT), Thrips obscuratus (Crawford), is an economic pest of various horticultural crops in New Zealand and is recognised as a quarantine pest globally. Two chemical attractants (ethyl nicotinate and 6-pentyl-2H-pyran-2-one), three dispensers, three trap designs and four trap heights were investigated to determine the most effective method for monitoring NZFT. Phenology of NZFT at two locations was compared., Results: 6-Pentyl-2H-pyran-2-one in a polyethylene bag dispenser was the most attractive lure formulation and exhibited high stability in release rate trials. There was no difference in NZFT catch between vertical-panel and cross-panel traps, but both caught significantly more than delta traps. However, both types of panel trap had unacceptably high by-catch of native insects. Catch of thrips increased with height from 0 to 3 m. Phenology of NZFT showed similar population trends at both locations, but with a timing difference of around 50 days., Conclusions: Delta traps containing 6-pentyl-2H-pyran-2-one in a polyethylene bag at 2 m above the ground is the recommended method for monitoring NZFT, significantly improving the sensitivity, accuracy and labour input compared with prior methods. Long-term monitoring of NZFT could lead to more accurate economic damage thresholds and timing for when to apply insecticides. © 2014 Society of Chemical Industry., (© 2014 Society of Chemical Industry.)

In many animals, processes occurring in one season carry over to influence reproductive success and survival in future seasons. The strength of such carry-over effects is unlikely to be uniform across years, yet our understanding of the processes that are capable of modifying their strength remains limited. Here we show that female light-bellied Brent geese with higher body mass prior to spring migration successfully reared more offspring during breeding, but only in years where environmental conditions during breeding were favourable. In years of bad weather during breeding, all birds suffered reduced reproductive output irrespective of pre-migration mass. Our results suggest that the magnitude of reproductive benefits gained by maximising body stores to fuel breeding fluctuates markedly among years in concert with conditions during the breeding season, as does the degree to which carry-over effects are capable of driving variance in reproductive success among individuals. Therefore while carry-over effects have considerable power to drive fitness asymmetries among individuals, our ability to interpret these effects in terms of their implications for population dynamics is dependent on knowledge of fitness determinants occurring in subsequent seasons.

Colonial breeding is widespread among animals. Some, such as eusocial insects, may use agonistic behavior to partition available foraging habitat into mutually exclusive territories; others, such as breeding seabirds, do not. We found that northern gannets, satellite-tracked from 12 neighboring colonies, nonetheless forage in largely mutually exclusive areas and that these colony-specific home ranges are determined by density-dependent competition. This segregation may be enhanced by individual-level public information transfer, leading to cultural evolution and divergence among colonies.

Background: Pheromones of two native leafrollers of economic importance to the New Zealand horticulture industry, Planotortrix octo [(Z)-8-tetradecenyl acetate and tetradecyl acetate] and Ctenopseustis obliquana [(Z)-5-tetradecenyl acetate and (Z)-8-tetradecenyl acetate], were reinvestigated and combined with pheromone of Epiphyas postvittana [light-brown apple moth, (E)-11-tetradecenyl actetate and (E, E)-9,11-tetradecen-1-yl acetate] to develop a single dispenser for mating disruption of three pest species for integrated pest management., Results: Additional compounds identified from pheromone gland extracts were characterised as repellents for P. octo. However, for C. obliquana from Central Otago, a change in ratio of (Z)-5-tetradecenyl acetate and (Z)-8-tetradecenyl acetate and the addition of three compounds found in the gland (dodecyl acetate, tetradecyl acetate and hexadecanal) led to a significant improvement in catch over previous lures. Males from Central Otago showed antennal electrophysiological responses to hexadecanal, unlike C. obliquana from Auckland, which did not. Three multiple-species disruption blends were devised in a single dispenser to target E. postvittana, P. octo and C. obliquana. Disruption of traps was recorded in single-tree replicates with all three blends, but the five-component blend was overall most effective at disruption and was deployed area wide in commercial orchard plots., Conclusions: Deployment of single dispensers into commercial stone fruit orchards led to disruption of trapping for the three species and measurable reductions in insecticide use in cherries, peaches and nectarines without increased fruit damage (assessed in apricots)., (Copyright © 2011 Society of Chemical Industry.)

Studies in a multitude of taxa have described a correlation between heterozygosity and fitness and usually conclude that this is evidence for inbreeding depression. Here, we have used multilocus heterozygosity (MLH) estimates from 15 microsatellite markers to show evidence of heterozygosity-fitness correlations (HFCs) in a long-distance migratory bird, the light-bellied Brent goose. We found significant, positive heterozygosity-heterozygosity correlations between random subsets of the markers we employed, and no evidence that a model containing all loci as individual predictors in a multiple regression explained significantly more variation than a model with MLH as a single predictor. Collectively, these results lend support to the hypothesis that the HFCs we have observed are a function of inbreeding depression. However, we do find that fitness correlations are only detectable in years where population-level productivity is high enough for the reproductive asymmetry between high and low heterozygosity individuals to become apparent. We suggest that lack of evidence of heterozygosity-fitness correlations in animal systems may be because heterozygosity is a poor proxy measure of inbreeding, especially when employing low numbers of markers, but alternatively because the asymmetries between individuals of different heterozygosities may only be apparent when environmental effects on fitness are less pronounced., (© 2011 Blackwell Publishing Ltd.)

Cultural transmission is thought to be a mechanism by which migratory animals settle into habitats, but little evidence exists in wild populations because of the difficulty of following individuals over successive generations and wide geographical distances. Cultural inheritance of migration routes represents a mechanism whereby geographical isolation can arise between separate groups and could constrain individuals to potentially suboptimal sites within their range. Conversely, adopting the parental migratory route in adult life, rather than dispersing randomly, may increase an individual's reproductive success because that strategy has already been proven to allow successful breeding. We combined a pedigree of related light-bellied Brent geese (Branta bernicla hrota) with 6 years of observations of marked birds to calculate the dispersal distances of adult offspring from their parents in both Ireland and Iceland. In both countries, the majority of offspring were found to recruit into or near their parental sites, indicating migratory connectivity in the flyway. Despite this kin structure, we found no evidence of genetic differentiation using genotype data from 1127 individuals across 15 microsatellite loci. We suggest that the existence of migratory connectivity of subpopulations is far more common than previous research indicates and that cultural information may play an important role in structuring reproductive isolation among them., (© 2010 Blackwell Publishing Ltd.)

1. It has been known for some time that the consequences of 'decisions' made at one point in an animal's life may not always be borne immediately. For example, numerous studies have demonstrated the trade-off between current and future breeding success across multiple taxa. 2. It is becoming increasingly clear that such processes may also operate among seasons, such that the conditions experienced at one point in the annual cycle may have significant downstream impacts, or 'carry-over effects', and this is particularly evident among migratory species. We might therefore predict that certain combinations of reproductive and migratory strategy could lead to profound carry-over effects. However, the extent to which these phenomena might generate variation in fitness within a population is unclear. 3. Here, we investigate how winter habitat selection in a long-distance migrant, with extended parental care (the Light-bellied Brent goose) is influenced by parental status and how this has a counterintuitive effect on subsequent breeding success. 4. Dominant individuals and groups generally monopolize the best quality resources. In the case of geese, families are dominant; however, our findings highlight a hidden cost to raising a family. Stable isotope analysis demonstrates that later in the non-breeding season, adults with families utilize lower quality resources than non-breeders. This is probably caused by parents being constrained in habitat choice by the lower foraging efficiency of their juveniles. Consequently, parental adults end the winter in poorer condition than non-breeders. 5. We further demonstrate that parents in one year are less likely than expected to breed again in the next year and suggest that this is caused by conditions during the non-breeding period being carried over into the breeding season. In conclusion, we demonstrate previously hidden costs to raising a family, which are likely to be important in terms of life-history evolution.

1. Individual variability in prey preferences can have marked effects on many demographic parameters from individual survival and fecundity to the vital rates of entire populations. A population level response is ultimately determined by individual prey choices; however, the effect of individual dietary choice is often overlooked. 2. We determined prey choice by individual consumers, light-bellied Brent geese Branta bernicla, during the overwintering period. Two hundred and eighty-one individuals were sampled at distinct temporal points over two winters. Stable isotopic ratios of carbon and nitrogen for blood cells and blood plasma, from each sampled individual were measured. Isotopic ratios for potential prey items were also measured. 3. Delta15N and delta13C for blood samples were both significantly different between sample months. Generally we found a decrease in both isotopic ratios during the course of the winter. All potential prey items were also isotopically distinct. Multisource mixing models (isosource) were used to determine the range of possible contribution to the diet of individuals. 4. During early winter, diet consisted almost exclusively of sea grass Zostera spp. The level of Zostera spp. in the diet dropped until mid-winter, and was supplemented by the utilization of green algae Ulva lactuca, and Enteromorpha spp., and terrestrial grasses. Terrestrial grass comprised an increasing proportion of the diet in late winter, representing virtually the exclusive food source by April. 5. By examining intrapopulation variability in resource utilization we highlight a number of ecologically important factors not addressed by previous population level studies.