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Michel Camilo On Fire Pdf

We review the fire ant research conducted by the ARS-South American Biological Control Laboratory (SABCL) since 1987 to find a complex of natural enemies in southern South America and evaluate their specificity and suitability for field release as self-sustaining biological control agents. We also include those studies conducted by the ARS-Center for Medical, Agriculture, and Veterinary Entomology in the United States with the SABCL collaboration. Ecological and biological information is reported on local fire ants and their microsporidia, nematodes, viruses, phorid flies, eucharitid wasps, strepsiptera, and parasitic ants. Their biology, abundance, distribution, detrimental effect, field persistence, specificity, and phenology are discussed. We conclude that the objectives of the ARS program in South America are being achieved and that the pioneering studies have served to encourage further investigations in the United States and other countries and advanced the implementation of biological control programs to decrease imported fire ant densities and damage. Still, several promising organisms should be further investigated for eventual field release in the near future.

michel camilo on fire pdf

During the last decade, S. invicta has been considered one of the 100 worst invasive exotic species [4]; this fire ant became a more global problem when it invaded ecosystems in the Caribbean Islands [5], Australia [6], New Zealand [7], Hong Kong, Taiwan [8], and mainland China [9]. Its eradication has been accomplished only in New Zealand [10].

In the United States, the imported fire ants cause many problems in the southeast and in some patches in California. They are a major public health concern because of their aggressive stinging behavior [11]. Although, for most individuals, this is just an irritating nuisance, for several hundred thousand people in the United States, sensitive to fire ants or highly allergic, the sting might cause severe reactions and eventually death [12]. Fire ants also injure domestic animals, livestock, affect wildlife [13, 14], native ants, and other arthropods [15, 16]. Structures, electrical devices, and agricultural crops can also be damaged [17, 18].

In disturbed North American environments, imported fire ants are dominant terrestrial arthropods [19]. Solenopsis invicta has displaced Neartic species of fire ants in the United States and adversely affected the diversity of the ant assemblages [15, 16]; however, the nature of the impact on native ant species has been controversial [20]. Some beneficial effects of fire ants such as predation on several agricultural and livestock pests have been also reported [20, 21].

In the United States, chlorine insecticides were used to control fire ants in the 1950s and 1960s, but they brought negative consequences to the environment [21]. A new bait with the insecticide mirex was believed to make fire ant eradication possible. However, in 1971, its use was highly restricted because of many environmental concerns and mirex registration was cancelled in 1977 [11, 21]. Since the 1980s, more environmentally friendly products have been used in the United States [11] and in other invaded countries. Still, the chemical approach is expensive, only provides temporary control, is detrimental to several nontarget organisms, and is not appropriate for large and/or sensitive environments. Consequently, the need of implementing control methods with less negative environmental impacts became a priority.

In late 1987, after three years of cooperative work with Brazilian researchers in Mato Grosso and Mato Grosso do Sul, Brazil, scientists from the IAMARL formally established the fire ant biological control program at the ARS-South American Biological Control Laboratory (SABCL) in Hurlingham, Buenos Aires province, Argentina [25]. Since then, the main objective of the program has been to find a complex of natural enemies of fire ants in their homeland, evaluate their specificity, and determine their suitability for eventual use in the United States against the red and black imported fire ants.

In this paper, we review the fire ant research conducted by SABCL researchers in southern South America since 1987. Several studies carried on in the United States by CMAVE scientists in collaboration with SABCL researchers are also included. We cover not only the occurrence of fire ant natural enemies and aspects of their biology and ecology, but also ecological studies on other South American fire ants.

Preliminary explorations for fire ant diseases in Argentina were conducted by researchers from IAMARL and SABCL in 1987 in the provinces of Buenos Aires, Entre Ríos, and Santa Fe [25]. The vial sampling of 425 fire ant colonies in 47 sites and the subsequent microscopic examination revealed the presence of the following pathogens: (1) Kneallhazia (=Thelohania) solenopsae Knell, Allen, and Hazard (Microsporidia: Thelohaniidae) at 41% of the sites and 11% of the colonies; (2) Vairimorpha invicta Jouvenaz and Ellis (Microsporidia: Burenellidae) at 11% of the sites and 2% of the colonies; (3) Myrmecomyces annellisae Jouvenaz and Kimbrough (Deuteromycotina: Hyphomycetes) at 15% of the sites and 2% of the colonies; (4) Mattesia sp. (Neogregarinida) at 7% of the sites and 1% of the colonies; (5) a mermithid nematode at 7% of the sites and 0.5% of the colonies. This preliminary overall occurrence of K. solenopsae and V. invictae in 13% of the colonies of S. richteri and S. quinquecuspis almost doubled the prevalence (7.6%) of the same infections on S. invicta in the area previously surveyed of southwestern Brazil [25].

Few records of parasitic nematodes exist for fire ants [72]. The diagnostic character for the occurrence of mermithid nematodes in ants is the enlarged gasters of the workers (Figure 5(a)). In the late 1980s, three species were reported for southern South America: (1) Tetradonema solenopsis Nickle and Jouvenaz from central-western Brazil in 2.9% of the 2,250 fire ant colonies examined; (2) a mermithid nematode from central-eastern Argentina in 0.5% of the 425 colonies examined; (3) an unidentified nematode from central-eastern Argentina, Uruguay, and southern Brazil in 4.3% of the 600 colonies sampled [73, 74].

At least 30 Pseudacteon species (Diptera: Phoridae) are parasitoids of Solenopsis fire ants in the New World and 23 attack South American fire ants in the Solenopsis saevissima species group [92, 93]. Fire ant decapitating flies are parasitoids of individual workers [94, 95].

VectorsUsing PCR techniques, Pseudacteon flies from Argentina were tested in the United States for their potential as vectors of the bacterium Wolbachia [105]. Seven of ten species tested were positive for four Wolbachia strains. Multiple infections were detected only in P. curvatus. Strains infecting the flies were not closely related to the sequences obtained from strains infecting S. invicta and S. richteri, indicating that these flies were not vectoring Wolbachia into these fire ant species. Pseudacteon decapitating flies do not appear to vector fire ant viruses [106]. More recently, Pseudacteon flies were tested as potential vectors of the microsporidia K. solenopsae and V. invictae [107]. Several species of flies that were reared from S. invicta-infected workers were confirmed as carriers of K. solenopsae. Detrimental effects on the development of fly pupae and on emergence of adult flies were not observed. These results indicated that Pseudacteon flies might vector K. solenopsae but actual vectoring remains to be confirmed. In contrast, V. invictae did not infect phorids reared from infected fire ants [107].

SurveysFifty-five species of Orasema have been described worldwide [124, 133], and more than 200 species have been estimated for the Neotropic (Heraty, pers. comm.). Orasema parasitoids were first reported on fire ants of the S. saevissima complex in Uruguay [134]; O. xanthopus (Cameron) was later found parasitizing up to 40% of the colonies of S. invicta and other fire ant species of the same complex in Brazil [24, 25, 99, 135, 136]. In Argentina, 11 species were reported, three of which were parasitoids of fire ants in Buenos Aires, La Pampa, and some of the northwestern provinces [123, 137].Between 2005 and 2007, the distribution of Orasema species and their ant hosts were intensively studied in Argentina and neighboring countries by excavating Solenopsis colonies in 73 sites in roadsides, pastures, and recreational areas [138]. A total of 731 colonies with brood were transported to the laboratory, separated from the soil by flotation [139] and the brood isolated [140] for Orasema individuals. Orasema was found in 29 sites parasitizing 13.5% of the 443 colonies in Argentina and 4.2% of the 288 colonies in Paraguay, Uruguay, and Bolivia. Five species were identified: (1) O. simplex was the most abundant, occurring at 17 sites and in 63.7% of the 72 parasitized colonies; (2) O. xanthopus and (3) O. salebrosa Heraty were found only at two sites; (4) O. aenea Gahan was found parasitizing fire ants for the first time at one site in Argentina; (5) O. pireta Heraty was found at one site parasitizing an unidentified Solenopsis species in Bolivia. In Paraguay and Uruguay, only O. simplex was present [138].Two new host species of Orasema within the S. saevissima complex were discovered: S. quinquecuspis in Argentina and S. macdonaghi in Uruguay.The wide variety of habitats and geographic distribution suggested that Orasema is a common parasitoid of fire ants in their native land. However, a second sampling of the Argentine sites conducted 6 to 18 months later revealed a field persistence in only 36.4% of the sites [138].


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