Abstract:

Softwood forestry with non-native tree species is increasing worldwide and especially in many developing countries of the Southern Hemisphere. Tree plantations are beneficial in environmental and socioeconomic aspects, but at the same time there are recognised costs associated with afforestation. Our aim was to revise the existing information on the impact of exotic conifer plantations in north-western Patagonia on insect biodiversity. A total of five studies were selected and, in these, not every insect group responded in a similar manner to the habitat replacement. There was a tendency towards a reduction in abundance and species richness of several insects inside pine plantations. This change in abundance and richness was especially evident for ant assemblages and when pine plantations were dense. Beetle assemblages, in turn, showed diverse responses to the replacement of native vegetation with forests depending on the native habitat matrix. Our findings confirm that practices that reduce tree density (via thinning or during plantation) should be recommended to minimise their impact on insect biodiversity in north-western Patagonia. The consistent behaviour of ant assemblages, coupled with their abundance, ease to sample and unambiguous taxonomy make them reliable candidates for long-term monitoring of the impact conifer forestation in north-western Patagonia, as well as probably in other regions of the world in which non-native pines replace natural environments.

EEA Bariloche

Author affiliation: Corley, Juan Carlos. INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina

Author affiliation: Dimarco, Romina Daniela. INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina

Author affiliation: Fischbein, Deborah. INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina

Author affiliation: Lantschner, Maria Victoria. INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina.

Author affiliation: Martinez Von Ellrich, Andres. INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina

Author affiliation: Masciocchi, Maite. INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina

Author affiliation: Mattiacci, Analia. INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina.

Author affiliation: Paritsis, Juan. INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina

Author affiliation: Villacide, Jose Maria. INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina

Abstract:

The German yellowjacket, Vespula germanica F., and common yellowjacket, Vespula vulgaris L. (Hymenoptera: Vespidae), are pests of significant economic, environmental, and medical importance in many countries. There is a need for the development and improvement of attractive baits that can be deployed in traps to capture and kill these wasps in areas where they are a problem. Yellowjackets are known to feed on fermenting fruit, but this resource is seldom considered as a bait due to its ephemeral nature and its potential attractiveness to nontarget species. We analyzed the headspace volatiles of dried fruit and fruit powder baits with and without Brewer's yeast, Saccharomyces cerevisiae, using gas chromatography-mass spectrometry, and we field tested these baits for their attractiveness to yellowjackets in Argentina. The addition of yeast to dried fruit and fruit powder changed the volatile compositions, increasing the number of alcohols and acids and decreasing the number of aldehydes. Dried fruit and fruit powder baits on their own were hardly attractive to yellowjackets, but the addition of yeast improved their attractiveness by 9- to 50-fold and surpassed the attractiveness of a commercial heptyl butyrate-based wasp lure. We suggest that further research be done to test additional varieties and species of yeasts. A dried fruit or fruit powder bait in combination with yeast could become a useful tool in the management of yellowjackets.

Author affiliation: Babcock, Tamara. University Fraser Simon; Canadá

Author affiliation: Gries, Regine. University Fraser Simon; Canadá

Author affiliation: Borden, John. Scott Canada; Canadá

Author affiliation: Palmero, Luis. University Fraser Simon; Canadá

Author affiliation: Mattiacci, Analia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Laboratorio de Ecología de Insectos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Masciocchi, Maité. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Laboratorio de Ecología de Insectos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Corley, Juan Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Laboratorio de Ecología de Insectos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Gries, Gerhard. University Fraser Simon; Canadá

Abstract:

The German yellowjacket, Vespula germanica F., and common yellowjacket, Vespula vulgaris L. (Hymenoptera: Vespidae), are pests of significant economic, environmental, and medical importance in many countries. There is a need for the development and improvement of attractive baits that can be deployed in traps to capture and kill these wasps in areas where they are a problem. Yellowjackets are known to feed on fermenting fruit, but this resource is seldom considered as a bait due to its ephemeral nature and its potential attractiveness to nontarget species. We analyzed the headspace volatiles of dried fruit and fruit powder baits with and without Brewer’s yeast, Saccharomyces cerevisiae, using gas chromatography–mass spectrometry, and we field tested these baits for their attractiveness to yellowjackets in Argentina. The addition of yeast to dried fruit and fruit powder changed the volatile compositions, increasing the number of alcohols and acids and decreasing the number of aldehydes. Dried fruit and fruit powder baits on their own were hardly attractive to yellowjackets, but the addition of yeast improved their attractiveness by 9- to 50-fold and surpassed the attractiveness of a commercial heptyl butyrate-based wasp lure. We suggest that further research be done to test additional varieties and species of yeasts. A dried fruit or fruit powder bait in combination with yeast could become a useful tool in the management of yellowjackets

Author affiliation: Babcock, Tamara. Simon Fraser University. Department of Biological Sciences; Canada

Author affiliation: Gries, Regine. Simon Fraser University. Department of Biological Sciences; Canada

Author affiliation: Borden, John. Scotts Canada; Canada

Author affiliation: Palmero, Luis. Simon Fraser University. Department of Biological Sciences; Canada

Author affiliation: Mattiacci, Analia. Consejo Nacional de Investigaciones Científicas y Técnicas-INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina.

Author affiliation: Masciocchi, Maite. Consejo Nacional de Investigaciones Científicas y Técnicas-INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina.

Author affiliation: Corley, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas-INTA. Estación Experimental Agropecuaria Bariloche. Grupo de Ecología de Poblaciones de Insectos; Argentina

Author affiliation: Gries, Gerhard. Simon Fraser University. Department of Biological Sciences; Canada

Abstract:

Abstract: Social insects rely on sophisticated communication channels and on individual decision making to achieve efficient foraging behavior. Through social interactions, individuals can acquire information inadvertently provided by a nestmate such as in trophallaxis. During this mouth-to-mouth food exchange, food receivers can perceive the odor of the food delivered by the donor and thus associate this odor with a food reward. Through individual experience, workers are able to perceive characteristic information of the food they have found and to evaluate food quality. Here, we determined which information, social or individual, is prioritized by the carpenter ants Camponotus mus in a foraging context. We exposed receiver ants to a deterrent and harmful food with the same odor they had previously learned in the social context of trophallaxis. We determined on which information individual ants based their decision to forage, whether on their individual evaluation of food quality or on the previously acquired social information. We show that the odor experienced in a trophallactic contact overrides individual food assessment to the extent that ants collect the deterrent food when the odor coincided with that experienced in a social context. If ants were exposed individually during a similar time to a food with the odor and afterwards, they were confronted with the same odor paired with the deterrent substance, and they rejected the deterrent food, contrary to what occurred when the odor was experienced in a social context. These results show that olfactory appetitive experiences in the social context play a fundamental role for subsequent individual foraging decisions. Individuals can acquire information by interacting directly with the environment or through social interactions with other individuals. Individual and social information may induce informational conflicts so that it is crucial to determine when it is worth ignoring one sort of information in favor of the other. Social insects are useful models to address this question: individuals evaluate and learn about their environment and rely on sophisticated communication systems. Here, we show that carpenter ants receiving social instructions, leading them to forage on a toxic food, overcome their natural rejection of this food, despite its noxious effects. Social instructions are, therefore, powerful enough to induce the consumption of food that would be otherwise rejected on the basis of the ants’ individual evaluation. Thus, although eusociality seems to favor sacrificing individual assessments in favor of social information, the resulting ‘social obedience’ may not always be adaptive. Significance Statement: Individuals can acquire information by interacting directly with the environment, or through social interactions with other individuals. Individual and social information may induce informational conflicts so that it is crucial to determine when it is worth ignoring one sort of information in favor of the other. Social insects are useful models to address this question: individuals evaluate and learn about their environment and rely on sophisticated communication systems. Here we show that carpenter ants receiving social instructions leading them to forage on a toxic food, overcome their natural rejection of this food, despite its noxious effects. Social instructions are, therefore, powerful enough to induce the consumption of food that would be otherwise rejected on the basis of the ants‘ individual evaluation. Thus, although eusociality seems to favor sacrificing individual assessments in favor of social information, the resulting ‘social obedience’ may not always be adaptive.

Author affiliation: Josens, Roxana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentina

Author affiliation: Mattiacci, Analia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentina

Author affiliation: Lois Milevicich, Jimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentina

Author affiliation: Giacometti, Alina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentina