Pierre Mineau

Bio: Pierre Mineau is an academic researcher from Environment Canada. The author has contributed to research in topics: Population & Herring gull. The author has an hindex of 38, co-authored 99 publications receiving 6705 citations. Previous affiliations of Pierre Mineau include University of Minnesota & Canadian Wildlife Service.

Systemic insecticides (neonicotinoids and fipronil): trends, uses, mode of action and metabolites

Abstract: Since their discovery in the late 1980s, neonicotinoid pesticides have become the most widely used class of insecticides worldwide, with large-scale applications ranging from plant protection (crops, vegetables, fruits), veterinary products, and biocides to invertebrate pest control in fish farming. In this review, we address the phenyl-pyrazole fipronil together with neonicotinoids because of similarities in their toxicity, physicochemical profiles, and presence in the environment. Neonicotinoids and fipronil currently account for approximately one third of the world insecticide market; the annual world production of the archetype neonicotinoid, imidacloprid, was estimated to be ca. 20,000 tonnes active substance in 2010. There were several reasons for the initial success of neonicotinoids and fipronil: (1) there was no known pesticide resistance in target pests, mainly because of their recent development, (2) their physicochemical properties included many advantages over previous generations of insecticides (i.e., organophosphates, carbamates, pyrethroids, etc.), and (3) they shared an assumed reduced operator and consumer risk. Due to their systemic nature, they are taken up by the roots or leaves and translocated to all parts of the plant, which, in turn, makes them effectively toxic to herbivorous insects. The toxicity persists for a variable period of time—depending on the plant, its growth stage, and the amount of pesticide applied. A wide variety of applications are available, including the most common prophylactic non-Good Agricultural Practices (GAP) application by seed coating. As a result of their extensive use and physicochemical properties, these substances can be found in all environmental compartments including soil, water, and air. Neonicotinoids and fipronil operate by disrupting neural transmission in the central nervous system of invertebrates. Neonicotinoids mimic the action of neurotransmitters, while fipronil inhibits neuronal receptors. In doing so, they continuously stimulate neurons leading ultimately to death of target invertebrates. Like virtually all insecticides, they can also have lethal and sublethal impacts on non-target organisms, including insect predators and vertebrates. Furthermore, a range of synergistic effects with other stressors have been documented. Here, we review extensively their metabolic pathways, showing how they form both compound-specific and common metabolites which can themselves be toxic. These may result in prolonged toxicity. Considering their wide commercial expansion, mode of action, the systemic properties in plants, persistence and environmental fate, coupled with limited information about the toxicity profiles of these compounds and their metabolites, neonicotinoids and fipronil may entail significant risks to the environment. A global evaluation of the potential collateral effects of their use is therefore timely. The present paper and subsequent chapters in this review of the global literature explore these risks and show a growing body of evidence that persistent, low concentrations of these insecticides pose serious risks of undesirable environmental impacts.

Pesticides néonicotinoïdes. Tendances, usages et modes d’action des métabolites

Abstract: Depuis leur decouverte dans les annees 1980, les pesticides neonicotinoides sont devenus la classe la plus largement utilisee des insecticides, dans le monde entier, avec des applications a grande echelle allant de la protection des plantes (cultures, legumes, fruits), aux produits veterinaires et aux biocides pour le controle des invertebres parasites en pisciculture. Dans cette revue, nous joignons la fipronil, un phenylpyrazole, aux neonicotinoides en raison de la similitude de leur toxicite, des profils physico-chimiques, et de leur presence dans l'environnement. Les neonicotinoides et le fipronil representent actuellement environ un tiers du marche mondial des insecticides ; la production mondiale annuelle de l'archetype des neonicotinoides, l'imidaclopride, a ete estimee au total a 20 000 tonnes de substance active en 2010. Le succes initial des neonicotinoides et du fipronil est du a plusieurs raisons : (1) il n'y avait pas de resistance connue a ces pesticides chez les ravageurs cibles, principalement en raison de leur developpement recent, (2) leurs proprietes physico-chimiques rassemblaient de nombreux avantages par rapport a celles des generations precedentes d’insecticides (c’est-a-dire, les organophosphores, les carbamates, les pyrethrinoides, etc.), et,(3) ils partagent et supposent des risques reduits pour l’operateur et le consommateur. En raison de leur nature systemique, ils sont absorbes par les racines ou les feuilles et transloques a toutes les parties de la plante, laquelle, a son tour, est effectivement toxique pour les insectes herbivores. La toxicite persiste pendant une periode de temps variable en fonction de la plante, de son stade de croissance, et de la quantite de pesticide appliquee. Une grande variete d'applications sont disponibles, y compris la NON Bonne Pratique Agricole(GAP)prophylactique d’application courante en enrobage de semences. En consequence de leur utilisation extensive et de leurs proprietes physico-chimiques, ces substances peuvent etre trouves dans tous les compartiments environnementaux, y compris le sol, l'eau et l'air. Les neonicotinoides et le fipronil fonctionnent en perturbant la transmission nerveuse dans le systeme nerveux central des invertebres.Les neonicotinoides imitent l'action des neurotransmetteurs, tandis que le fipronil inhibe les recepteurs neuronaux. Ce faisant, les premiers stimulent en permanence les neurones conduisant finalement les invertebres cibles a la mort. Comme pratiquement tous les insecticides, ils peuvent egalement avoir des effets letaux et subletaux sur les organismes non cibles, y compris les vertebres predateurs d'insectes. En outre, une gamme d’effets synergiques avec d'autres facteurs de stress a ete documentee. Ici, nous passons en revue de facon extensive leurs voies metaboliques, montrant comment les composes specifiques et les metabolites communs, lesquels peuvent eux-memes etre toxiques, forment ensemble deux cas. Ceux-ci peuvent entrainer une toxicite prolongee. Compte tenu de leur large expansion commerciale, leur mode d'action, leurs proprietes systemiques chez les plantes, leur persistance et leur devenir environnemental, couples avec des informations limitees sur les profils de toxicite de ces composes et de leurs metabolites, les neonicotinoides et le fipronil peuvent entrainer des risques importants pour l'environnement. Une evaluation globale des effets collateraux potentiels de leur utilisation est donc opportune. Le present document, et les chapitres suivants dans cette revue de la litterature mondiale, explorent ces risques et montrent une quantite croissante de preuves qui, sur la base de la persistance et de faibles concentrations de ces pesticides, posent de serieux risques d’impacts environnementaux indesirables.

Forced Copulation in Waterfowl

Abstract: 1. Although almost all waterfowl (ducks, geese and swans comprizing the family Anatidae) have basically monogamous mating systems, males of 39 species have been observed to perform or attempt forced copulation (FC) (previously called "rape"). 2. Suggestions that FC is an artifact of crowding in urban mallards, an outlet for thwarted male sex drive, a component of territory defence, or an alternative reproductive strategy of unpaired males are not supported by available evidence. 3. In the case of the mallard, HEINROTH'S (1911) interpretation of FC as a secondary insemination method whereby paired males increase their reproductive success by fertilizing some of the eggs laid by females other than their mate is supported by evidence of various kinds. FCs are performed by paired males; they occur during periods in the breeding season when eggs are being fertilized; they are directed mainly at females in prelaying and laying condition; paired males usually defend their mates against males attempting FC (suggesting defence of genetic paternity); paired males have been seen to copulate forcibly with their own mates after the latter have been subjected to FC (suggesting an antidote insemination strategy). 4. Experiments on captive mallards have shown that eggs can be fertilized by sperm delivered during FC and, since females can store viable sperm for up to 17 days, sperm competition must be taking place. Artificial insemination experiments have shown that (a) the second of 2 competing inseminations 6 hours apart overlays the former insemination and is 70% more potent, (b) there is an insemination "window" within 1 hour of oviposition when the next egg in the clutch is fertilized. The extent to which males time their copulations (FCs, pair copulations, forced pair copulations) to take advantage of these patterns of sperm competition is not known. 5. Studies of the lesser snow goose, northern pintail and lesser scaup indicate that FC is a secondary reproductive strategy of paired males in these species also. Observations on 13 species of dabbling duck provide additional evidence for the selection of fertile females as FC targets and the development of male tactics for achieving and combatting FC. 6. It is difficult to rule out the possibility that females could derive certain benefits from FC inseminations (e.g. genetic diversity of offspring) but the costs and risks of being involved in FC assaults can be high and the females apparently try to avoid FC. Female dabbling ducks can be damaged, or even killed, during assaults and female escape behaviour (high flights, diving, hiding in cover) entails energetic costs and wastage of time that are presumably detrimental to females during the period when they are producing eggs. 7. As HEINROTH suggested, FC probably does not occur in swans, most geese and shelducks because it is incompatible with the major roles that paired males play in defence of breeding territories, mates, nest-sites and broods in these groups. The occurrence of FC in snow and Ross goose may be facilitated by colonial nesting.. 8. Among dabbling ducks, male territoriality is associated with strong mate-guarding and these characteristics appear to conflict with male FC activities. Involvement of paired males in extrapair courtship, polygyny and brood-care may produce additional conflicts with FC behaviour in certain species. 9. In at least 4 species of waterfowl (mallard, northern pintail, lesser snow goose, lesser scaup) behavioural evidence indicates that FC is part of a mixed male reproductive strategy of the type postulated by TRIVERS (1972). Rigorous testing of the hypothesis will require studies to (a) assess the incidence of multiple paternity in wild clutches, (b) distinguish species (or populations within a species) in which paired males actively pursue FC tactics from those in which they merely capitalize on incidental opportunities for FC.

Influence of Diet On the Distribtion of Nitrogen Isotopes in Animals

Abstract: The influence of diet on the distribution of nitrogen isotopes in animals was investigated by analyzing animals grown in the laboratory on diets of constant nitrogen isotopic composition. The isotopic composition of the nitrogen in an animal reflects the nitrogen isotopic composition of its diet. The δ^(15)N values of the whole bodies of animals are usually more positive than those of their diets. Different individuals of a species raised on the same diet can have significantly different δ^(15)N values. The variability of the relationship between the δ^(15)N values of animals and their diets is greater for different species raised on the same diet than for the same species raised on different diets. Different tissues of mice are also enriched in ^(15)N relative to the diet, with the difference between the δ^(15)N values of a tissue and the diet depending on both the kind of tissue and the diet involved. The δ^(15)N values of collagen and chitin, biochemical components that are often preserved in fossil animal remains, are also related to the δ^(15)N value of the diet. The dependence of the δ^(15)N values of whole animals and their tissues and biochemical components on the δ^(15)N value of diet indicates that the isotopic composition of animal nitrogen can be used to obtain information about an animal's diet if its potential food sources had different δ^(15)N values. The nitrogen isotopic method of dietary analysis probably can be used to estimate the relative use of legumes vs non-legumes or of aquatic vs terrestrial organisms as food sources for extant and fossil animals. However, the method probably will not be applicable in those modern ecosystems in which the use of chemical fertilizers has influenced the distribution of nitrogen isotopes in food sources. The isotopic method of dietary analysis was used to reconstruct changes in the diet of the human population that occupied the Tehuacan Valley of Mexico over a 7000 yr span. Variations in the δ^(15)C and δ^(15)N values of bone collagen suggest that C_4 and/or CAM plants (presumably mostly corn) and legumes (presumably mostly beans) were introduced into the diet much earlier than suggested by conventional archaeological analysis.

Sperm competition and sexual selection

Abstract: General Themes: G.A. Parker, Sperm Competition and the Evolution of Ejaculates: Towards a Theory Base. A.P. Moller, Sperm Competition and Sexual Selection. W.G. Eberhard, Female Roles in Sperm Competition. J. Wright, Paternity and Paternal Care. Taxonomic Treatments: L.F. Delph and K. Havens, Pollen Competition in Flowering Plants. D.R. Levitan, Sperm Limitation, Gamete Competition and Sexual Selection in External Fertilizers. N.K. Michiels, Mating Conflicts and Sperm Competition in Simultaneous Hermaphrodites. B. Baur, Sperm Competition in Molluscs. M.A. Elgar, Sperm Competition and Sexual Selection in Spiders and Other Arachnids. L.W. Simmons and M.T. Siva-Jothy, Sperm Competition in Insects: Mechanisms and the Potential for Selection. C.W. Petersen and R.R. Warner, Sperm Competition in Fishes. T.R. Halliday, Sperm Competition in Amphibians. M. Olsson and T. Madsen, Sexual Selection and Sperm Competition in Reptiles. T.R. Birkhead, Sperm Competition in Birds: Mechanisms and Function. D.A. Taggart, W.G. Breed, P.D. Temple-Smith, A. Purvis, and G. Shimmin, Reproduction, Mating Strategies and Sperm Competition in Marsupials and Monotremes. M. Gomendio, A.H. Harcourt, and E.R.S. Roldan, Sperm Competition in Mammals. T.R. Birkhead and A.P. Moller, Sperm Competition, Sexual Selection and Different Routes to Fitness. Index.

The Economic Value of Ecological Services Provided by Insects

Abstract: In this article we focus on the vital ecological services provided by insects. We restrict our focus to services provided by “wild” insects; we do not include services from domesticated or mass-reared insect species. The four insect services for which we provide value estimates—dung burial, pest control, pollination, and wildlife nutrition—were chosen not because of their importance but because of the availability of data and an algorithm for their estimation. We base our estimations of the value of each service on projections of losses that would accrue if insects were not functioning at their current level. We estimate the annual value of these ecological services provided in the United States to be at least $57 billion, an amount that justifies greater investment in the conservation of these services.