Pests Of Man Research Articles

The Simuliidae (Diptera) of the River Oder and its tributaries, with special reference to the re-appearance of Simulium (Schoenbaueria) nigrum (Meigen) in larger rivers in Central Europe

An investigation was carried out over a five-year period into the blackfly fauna of one of the most important rivers of the North-Central European lowlands, the Oder, together with its major tributaries (Nysa, Stobrawa, Oława, Barycz, Bobr, Kroisa, Lausitzer Neisse, Warta, Notec), from its source in the Oder Hills to its mouth in the Baltic Sea. Thirteen species were found. The two dominant indicator species, Simulium (Simulium) reptans (Linnaeus) and Simulium (Schoenbaueria) nigrum (Meigen), develop populations of plague proportions within this catchment area. Blackflies of the subgenus Schoenbaueria Enderlein have not been found in Germany or Poland for more than 70 years. However, since 1997, the species S. (Sch.) nigrum was found in the River Oder in enormous numbers together with S. (S.) reptans, and in the vicinity of their breeding sites in Poland and eastern Germany both species are serious pests of man and grazing animals. Notes are given on the biology, distribution and habitat preferences of S. (Sch.) nigrum. The paper concludes with a comparison of the River Oder with some other Central European rivers in respect of its blackfly fauna, together with data on the phenology of the two indicator species.

Advances in Cow Dung Ecology: International Aspects of the Australian Bush Fly Research Programme

Intensive research carried out over the last 20 years on the biology and control of the Australian bush fly, Musca vetustisima, a widespread and irritating pest of man in that region, has provided a wealth of information about the community relationships of fauna in the cow dung pats which provide the breeding habitat of the fly. The extension of this project to South Africa and to Southern Spain in the search for exotic dung beetles or allied controlling agents to deal with both the bush fly and the blood-sucking buffalo fly, Haematobia, has given this programme a wider significance.

Chemical attractants tested against the Australian bush flyMusca vetustissima (Diptera: Muscidae)

A number of chemical compositions known to attract several synanthropic and pest fly species were tested against the Australian bush flyMusca vetustissima, a severe and persistent pest of man and domesticated and wild mammals. A standard composition containing small quantities of trimethylamine and indole, blended with large amounts of ammonium sulfate and anchovy meal, showed good attractancy against this fly. Deletion of ammonium sulfate did not significantly alter attractancy. Similarly, incorporation ofn-butyric acid and linoleic acid into the formulation did not alter attractancy, nor did addition of several carbonates and bicarbonates. Skatole, a closely related compound to indole, decreased attractancy significantly. In all the tests, the attractant compositions lured greater number of females than males. The attractancy of the standard composition was studied and compared with equal amount of fresh cattle dung. Chemical attractants lured bush flies and not dung beetles, while dung attracted both flies and beetles. The dung resource was 4.6 × more attractive to flies than the standard attractant composition. This suggests that there are other chemical attractants emanating from dung that warrant isolation and identification work. Nevertheless, the chemical attractants studied here provide a starting point for further investigations. The ratio of female to male flies attracted to humans was greater than the ratio of flies attracted to chemicals. The sex ratio of flies netted from human host was 3.0, while the sex ratio of flies attracted to chemical attractants was 1.8. The preponderance of females attracted to both sources was probably due to physiological requirements of the sexes.

Biology and Bionomics of Bloodsucking Ceratopogonids

In recent years there has been increasing attention paid to three genera [Culicoides, Leptoconops, Forcipomyia (Lasiohelea)] of ceratopogonids, whose females feed on warm-blooded vertebrates. This habit makes them pests of man and livestock. They are a nuisance to humans living on the coast and in poorly drained inland areas, but they are most important as vectors of virus diseases that are transmitted to domestic animals. Culicoides are proven vectors of bluetongue to sheep and cattle (93) and have been incriminated in the transmission of horse sickness to equines and ephemeral fever to cattle (26). The involvement of bloodsucking ceratopogonids in the transmission of human and animal diseases was reviewed in 1965 (60) and their bionomics and control in 1962 (59) and 1969 (61). The present review refers only to work covered in the latter two articles where necessary for the appreciation of more recent research. Current interest in ceratopogonids has been fostered by a biannual news letter, Ceratopogonid Information Exchange, edited by J. Boorman, Animal Virus Research Institute, Pirbright, Woking, Surrey, U.K.

Insect growth regulating agents for control of arthropods of medical and veterinary importance.

Extremely low concentrations of insect growth regulators (IGRʼs) have controlled mosquitoes, midges, flies, and biting lice in field tests. This effectiveness is undoubtedly related to the protected habitat of many of these pests of man and animals. Thus, species of Aedes have been controlled by applying as little as 0.14 kg IGR/hectare of water surface to the larval environment, but other species of mosquitoes such as Culex must be treated with much higher concentrations. All insects tested have shown marked susceptibility at a certain stage: 4th-instar Aedes larvae are controlled with 0.014 kg/hectare, but populations of mixed ages require 10 times that amount. Slow-release formulations of IGRʼs or those that protect the IGR from ultraviolet light are more effective. Otherwise, repeated applications are usually necessary to control a population containing all stages of a species. Development of new methods of application is being increasingly stressed, and feeding the IGR to cattle to control manure-breeding insects has been successful. Some IGRʼs have a rather broad-spectrum effect, particularly against manure-breeding flies; others are Selective, and a considerably greater quantity is needed for control of one species of fly than for control of another species.

MOSQUITOES AND HUMAN DISEASE IN CANADA

AbstractIn the early 19th century, malaria was indigenous in Upper Canada (Ontario), but indigenous infection has not been seen in Canada since about 1909. For many years mosquitoes were regarded principally as harmless pests of man and domestic animals until the recognition of a number of mosquito-borne viruses. At present, mosquitoes in Canada are known to be involved in the maintenance or spread of at least seven arboviruses. One of these viruses, western equine encephalomyelitis, occurs in epidemics in man and horses at irregular intervals in the western provinces. The extent to which the other arboviruses might cause disease in man or domestic animals in Canada is unknown at present but California encephalitis virus infection rates can be high in human residents of central Saskatchewan, central Alberta, and southern British Columbia. On the basis of observations made in the United States, St. Louis encephalitis virus could pose a threat to public health in Canada whereas the Cache Valley virus might involve livestock. Even if man and livestock are not involved at present in epidemics of disease due to these viruses, the presence of the viruses and their vectors should be of concern. Epidemics could arise either from amplification of causal viruses already present in indigenous foci or by amplification of viruses from new enzootic foci recently established by extension of the geographic ranges of the viruses. Evidence indicating which category each of the known viruses in Saskatchewan belongs to is briefly reviewed. Japanese B encephalitis virus has not yet been seen in Canada but the environmental prerequisites for an epidemic or epizootic due to this virus appear to be present and awaiting the arrival of the virus.

A CONTRIBUTION TO THE BIONOMICS OF THE TABANIDAE (DIPTERA) OF ALGONQUIN PARK, ONTARIO: SEASONAL DISTRIBUTION, HABITAT PREFERENCES, AND BITING RECORDS

Abstract Some aspects of the biology of the Tabanidae (e.g., seasonal distribution, relative abundance, habitat preferences, and innate host preferences) which influence the extent to which certain species are found biting various host species are discussed in relation to the tabanid population of the southern portion of Algonquin Park, Ont., Canada. Of the 36 species collected in this study, relatively few were sufficiently abundant to constitute serious pest problems.The analysis of collections of tabanids from carbon dioxide-baited traps placed in different habitat types revealed several patterns of distribution of the Algonquin Tabanidae: ubiquitous, exclusively sylvan, preferentially sylvan, riverine, and riparian species.Lists of the tabanids attracted to or biting man, moose, and white-tailed deer are presented. These lists constitute the first extensive records of the Tabanidae attracted to the Cervidae in the boreal forest region of Canada.The Chrysopinae selected smaller hosts than the Tabaninae and were severe pests of man whereas the Tabaninae were only minor pests of man but severe pests of moose. The tabanids attracted to deer presented a picture which was intermediate between that of man and moose. In addition, a few species of tabanids were unusually common on one or more hosts suggesting that some species may have innate preferences for certain hosts.

Blood Sucking Asian Leeches of Families Hirudidae and Haemadipsidae

Abstract : The report is a general, but far from complete account of the Asian blood-sucking aquatic leeches of family Hirudidae and the land leeches of family Haemadipsidae. While other blood-sucking leeches occur in Asia, the majority of the species known as pests of man and domestic animals are land leeches of genus Haemadipsa, and aquatic leeches of genera Hirudinaria, Hirudo, and Dinobdella. In western Asia the nasal leeches of genus Limnatis are also of human and veterinary medical importance. The report contains information on the identification, distribution, and habits of each of the species discussed. Finally, information is given on personal protective measures against leeches, and on the effectiveness of insecticides, molluscicides, and natural enemies in leech control. (Author)

Reduction of parathion residue on celery.

We have seen in the past 20 years the rapid growth and expansion in the use of chemicals in the control of insect pests of man and animals and in weed control. Their use is an absolute necessity if we are to continue to attempt to meet the food needs of our time and the daily increasing needs with increasing population. Pesticides, as necessary as we believe they are, provide us with the now well-known concomitant complex problem of residues. The goal toward which we aspire, of course, is that of a pesticide which will perform its work and then disappear entirely in its toxic form from the environment so that no residue problem will exist. One of the more difficult areas of pesticide research is that of removing from a particular commodity any toxic residue, altering the commodity in as small a way as possible. This is not an unexpected difficulty since most pesticide formulations emphasize broad contact and adherence to the sprayed or dusted object for best possible pest control. The particular interest in the research reported here is the attempted removal of parathion from mature celery. Some work was also done with escarole and lettuce which will also be reported.

CONENOSE BUGS (TRIATOMA) VISIT UNOCCUPIED BOY'S CAMP IN LOS ANGELES.

Previous studies of Wood (1953, 1960) and Mehringer et al (1958, 1961) have shown Triatoma protracta protracta (Uhler) to be a pest of man in Griffith Park Youth Camps. The bugs attack man under temperature stress and during absence of natural rodent hosts. Details of habitat are described by Mehringer & Wood (1958). During the summers of 1962 & 1963, the Boys' Camp (City Fire Dept. Map Areas 29 & 30) remained unoccupied except for caretaker Arthur L. Gladwill. Collections were made of Triatoma during 25 July-21 Aug. 1963 (Anderson) and continued to 14 Oct. by Gladwill who compiled most of the data.

THE PROBLEMS OF BITING MIDGES (DIPTERA: CERATOPOGONIDAE) IN QUEENSLAND

AbstractQueensland's geographical position gives a midge fauna active in all seasons, containing numerous species suspected or known to feed on birds and mammals. Taxonomy is incomplete but allows a start on the problems midges present both as pests of man, retarding settlement and tourist industry, and as vectors of disease, especially their potential as vectors of the blue‐tongue virus in sheep and of African horsesickness. More knowledge of midge taxonomy and biology is needed to solve these problems. Known Queensland species of Culicoides, Lasiohelea, Leptoconops and Styloconops are listed.

Studies of Populations of Adult and Immature Culicoides sanguisuga (Diptera: Ceratopogonidae)1

The method used in making landing-rate counts of Culicoides sanguisuga (Coquillett), an abundant pest of man in the Adirondacks, is described. Landing rates were low initially at a given site, and increased to a peak 10 to 12 minutes later. Counts were highest about an hour after sunrise and at sunset. In open meadows the counts generally declined to zero during the day between the morning and evening peaks. In moist, shaded sites, protected from the wind, landing rates diminished but punkies continued to be annoying during the middle of the clay. It is suggested that the rate of moisture loss is an important factor influencing the activity of the punkie, and a close relationship between the evaporation rate and landing rate is demonstrated. Seasonal changes in populations of C. sanguisuga , as indicated by landingrate counts and light-trap collections, were comparable. The first females appeared in late May. Populations then increased rapidly and reached peak numbers in late June and early July. The numbers diminished slowly thereafter and punkies were found only in small numbers after mid-August, although occasional specimens were present into October. C. sanguisuga overwinters in the larval stage. In 1961, larval populations were high in early May, then declined during the period of pupation from late May into early June. Numbers increased thereafter owing to the appearance of recently hatched small larvae. Prepupation population levels were reached by late July.

Occurrence of Eye Gnats (Hippelates spp.) in the Central San Joaquin Valley, California

An adult. Hippelates eye gnat survey was conducted in the San Joaquin Valley near Fresno, California, from March 1960 to March 1961. Collecting equipment and techniques included egg bait traps and human attractants. A reliable volumetric method of estimating numbers of eye gnats in large collections was developed. Hippelates collusor (Townsend), a highly anthropophilous species, was found in greatest numbers and was observed to be the most important pest of man. The second most numerous species trapped, H. robertsoni Sabrosky, was not an important pest of man. Small numbers of two minor species, H. dorsalis Loew and H. microcentrus coquillett, also were taken. The numbers of H. Collusor were related to average weekly temperatures throughout the year. The numbers of H. robertsoni increased with average weekly temperatures until the average temperatures exceeded 70° F., then declined. The threshold of gnat. activity in terms of average weekly temperature was approximately 50° F.

Biology and Control of Labrador Black Flies (Diptera:Simuliidae)

Twenty-five species of Simuliids are listed with indications of their relative abundance, importance as pests of man, seasonal appearance, temperature requirements, and larval habitats in Labrador. Seven of these are undescribed species. The most important species are Simulium venustum Say and Prosimulium hirtipes (Fries).A circular area of 200 square miles around Goose Bay airport was surveyed for important breeding sites. Of 163 streams and rivers investigated, 77 were suitable as larval habitats, and larvae were virtually eliminated from them in June, 1950, by applications of a 10 per cent, solution of DDT in fuel oil at the rate of 1–5 p.p.m.- minutes from a helicopter, conventional aircraft, or boats, or by hand application from the ground. Methods of application are discussed.The repopulation of the area by black flies was studied, and deductions are made concerning the flight habits of the most important species. On the basis of averages throughout the season, a great reduction in numbers of black flies at the centre of the area was obtained, and a worth-while reduction to a distance of between 4 and 6 miles from the centre. Even near the centre of the area, however, black flies were sometimes troublesome late in the season.It is suggested that, where P. hirtipes is the important species, relief for at least one season could be secured by eliminating larvae within a radius of 2 miles; for S. venustum, 6 miles is suggested as a suitable radius. No adverse effects on useful animals were recorded.

Successful Feeding Experiments with an Adult Trombiculid Mite (Order Acarina)

ALTHOUGH certain species of Trombiculid mites belonging to the sub-family Trombiculinae have long been suspected of being the carriers of tsutsugamushi disease, now more commonly referred to as scrub typhus, it is only recently that Blake et al.1 have demonstrated the presence of Rickettsia orientalis in Trombicula fletcheri Womersley and Heaslip. In their paper., which contains a valuable review of the literature on scrub typhus, they say that "existing knowledge regarding the life-history, habits and bionomics of trombiculid mites is quite inadequate in view of their importance as disease vectors and pests of man". This is particularly true of the feeding habits of the nymphal and adult stages. Miyajima and Okumura2, who first established Trombicula akamushi (Brumpt) as the vector of tsutsugamushi fever in Japan, say that "in nature the nymph and adult seem to live on the juice of plants". Womersley and Heaslip3, too, appear to believe that the adults are probably vegetarian. Banks4, on the other hand, makes a general statement to the effect that the mature mites feed on small insects, and mentions particularly plant lice, young caterpillars and grasshopper eggs. But l*e gives no details of any observations on the subject. Blake et al. (loc. cit.), in summing-up our present knowledge of the feeding habits of the nymphal and adult stages, say that "the food of these stages is variously reported to include plant juices, decaying organic matter and insect excrement". It would appear., therefore, that though adults have occasionally been reared in the laboratory there are few, if any, definite records on their feeding habits. Indeed it would seem doubtful whether they have actually been observed in the act of feeding.

Indigene Versus Alien in the Development of Arid Hawaiian Vegetation

The conflicts of the old and the new, the conservative and the radical, the classicist and the romanticist, represent fundamental types of activity in the organic world. We find that their observation and study have been prominent for centuries. More recently, with the extensive introduction into new lands of human beings, of cultures and civilizations, of plants and animals, and of diseases and pests of man, long established equilibria have been disturbed and new ecosystems of very different nature are in process of formation. One unusually interesting aspect of this readjustment is that which is taking place today between the indigenous and the alien plants of tropical regions of both hemispheres. The author's purpose is to reveal the problem as one involving the ecology of individual species, and not involving an anthropocentric sentimentalism that breeds a spirit of defeat and that prevents experimentation and further observation. The island of Oahu, Territory of Hawaii, is the scene of one of these conflicts, where the plant life has been vastly altered since the impact of Europeans and their civilizations. More than two thousand cultivated and naturalized plants have been

THE COAST TICK (IXODES CALIFORNICUS BANKS) PROBLEM IN BRITISH COLUMBIA

During recent years the tick, Ixodes californicus Banks, has attained considerable prominence as a pest of man, pets and livestock in British Columbia coastlands. This progression from a parasite of relatively little importance to one of major economic significance has been brought about not only by the gradual spread of human settlement into the habitat of the tick, but also by a resulting marked increase in the population of the pest. The present economic status of this tick, as observed by officers of the Dominion Entomological Laboratory at Kamloops during the past eight years, is presented herewith.

New Blood-Sucking Flies from Utah(Simuliidæ, Diptera)1

Flies of the family Simuliidae have long been known as serious pests of man and livestock in various sections of the country. Literature abounds with life-histories, taxonomies, and distribution of these pests; in none of the writings, however, have the writers found mention of members of this family occurring in Utah. From the material at hand we list two genera and five species from this state, four species of which are described as new.

The Bionomics of Some Tabanidæ (Diptera).*

Although the early stages of the Tabanidae have been studied in considerable detail, both in this country and in other parts of the world, only a relatively few species of this large family were involved in these studies. The importance of horseflies as irritating pests of man and domestic animals, and as potential vectors of disease organisms makes a further study of their biology desirable. The following study was carried out at Ithaca, N. Y., only a few larvae being collected elsewhere.