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Machine-read from the scan, so expect some errors. Lines that couldn’t be read are left out.
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a. By the djrectionof DASG a medical entomologicalsurveywas conducted on selectedcoral islets of the Eneweta~<Atoll to determineall real and potentialentomologicalproblems to be encounteredduring cleanup b. Biologicallyand ecologicallythe islets arc still evolvingand represent a fragile and unstablebiologicalcommmity. The introductionof higher animal life forms has been artifici.!l.Mis situationhas allowed a number of speciesto inlha’oitthe isletsuncheckedby natural c. A variety of factorshave successfullylimitedthe t!e establishment 1) Limited accessibilityof the islets. 3) Limited land area, breedingsites, appropriatefood sourcesand d. These factorshave, for the most part, restrictedthe establishment of medicallyimportantarthropodaon the islets. a. A total of 12 isletswere selectedfor surveillance.Selectionwas based on the followingcriteria: 1) Size. BEST AVAILABLE COPY Operationalaspects relatedto cleanupmission, Informationprovidedby engineerssurveyingvarious islets.
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Each islet was surveyedidentically. Walk-throughsurveillance with insect nets and collectingequipmentwas conducted. All possible breeding sites and harborageswere sampled. Light traps were set out in areas where wind shelterwas providedto samplenocturnalactivity. Rodent surveillancewas visual and with traps. Have-a-Hearttraps were set in associationwith burrows,nests, high activityareas and equipmentindigenousto the survey teams providedample work and identificationrequirements. Insect identificationswere made microscopicallywith the use of appropriatekeys. a. The predominant problem on the atoll is the largepopulationof rats. llvosp$ciesof rats were noted, 1) Rattus rattus (roof rat)
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The total absenceof naturalpredationon the’isletsbs allowedthe ‘ populationto soar and-be limitedonly by populationpressure, the exceptionof the islet of Enewetakthe rat ’populationreachedtie Mice, though not taken in traps, are presenton the islets. Evidence~~ used to determinetheir presencewas the collectionof frass and signs of damage. The populationof mice on the individualislets is prqbably low’dueto successfulcompetitionfrom the rat population. Ectoparasitesfound on rats were limitedto mites of undetefined ‘ ‘ species. No ticks or fleas were found. Three methodswere used to obtain ectoparasitesfrom the rats. 3) Visual examinationof the body and hair with the aid ofmsa~ifying Lack of higher ectoparasiticpopulationis attributedto extremely limited contactwith other mammalianspecies. Various speciesof stinging (aculeate)wasps are present on all of the islets. Polistes fuscatus-”var.aurifer is the most aggressive. Ropalidiamargmata and an unident~pecies in the familyVespidaeare also present. Parasiticwasps of the family Sphecidaewere also collected. In all cases the wasp populationsper islet is low. However, where present the wasps tend to be concentratedin small areas. was locatedin a refrigeratorbuilding. The colonywas old but viable and nests varied in size from the diameterof a quarter to the size of a football. About 25 wasps were present in the refrigeratorbuildingand a nurber were observedforagingin the area. The estimatedliving populationof the colony is between 100 and 150 wasps. Limitednatural food sourcesand high winds have severlyrestri.cte the numbers of wasps capable of survivingon the islets. Normal fdods such as lepidopterouslarvae,nectar etc, are extremely limited. Coloniesare thereforesmall and focal. mey may US~MII? be locatedin dense foliage,well shieldedfrom the wind and close to the ground. Some & marginatawere observednestingup to six feet above ground on the lee side of the foliage.
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4) The wasps normallyare not aggressiveand do not seek out or attack people. The sting is in accordancewith most ~listene type stingswith a wheel-flairreactionand pain lasting from althoughsome people recalledbeing stung 4 or 5 times. One report of 20 stings could not be confirmedand is considered only noticedwhen the integrityand safetyof the colony or nest was directlythreatened. f. No mosquitoeswere collectedthoughlight traps,natural and artificial nesting stationswere used. Furthermore,interviewsindicatedno one has been bitten by a mosquito. High winds are the major factOr f?” Spiders are present throughoutthe atoll’s islets. Specimensof what appears to be the black widow have been collectedby personnelof the MPML thoughnone were found during this survey. The only island reportingthe collectionof ~. mactans is Enjebi (Jane). Specimens have been sent to the BishopM..seum,Hawaii for confirmation. No other venomous spidershave been reportedfrom or collectedfrom the h. Snakes are not present on EnewetakAtoU. i. Flies affectingman appear limitedto severalspeciesof the genus Musca or house flies and sarcophagi(fleshflies). Inmost cases the =ing areas are in and aroundwaste disposalsites. Populationsare small and of nuisancevalue. Some transmissionof is possible thoughnot likelydue to good sanitary The rodent populationsrequirecontrolof the earliestpossible date. Baitingwith zinc phosphideis the most acceptableto this writer. Howe other baits are available. A specialannex to this report will be preparedwith specificguidelineson baiting requirements. . Bait stationscontainingzinc phosphidein a formulationacceptableto the rats shouldbe used. Severalprebaitsshouldbe testedwithout the presence”ofzinc phosphideto determinewhich is the most acceptable to the rats. Upon completionof prebaitingthe actual zinc phosphide bait should be employed. Each islet shouldbe prebaitedimmediately prior to baiting.
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Prebait and bait stationsshould be placed in the exact”same locations. Placementofprebait afidbait shouldbe directlyassociatedwith of the baiting cycle. Unconsumedbaits shouldbe retrievedwithin48 - 72 hours of their placementto limit contactwith non target organisms., The process of cleaningup the isletsby engineerswill itselfhave”’ “. and food sources. This combinedintegratedcontrolshould significantly will be requiredalong with “rodentproofing”of buildings. Criticalprebaiting,baiting and post surveillanceshouldbe conducted by certifiedpest controlpersomel (MOS-91S,civilianor engineers) under the direct supervisionof a professionalentomologist. Thereafter engineeringpersomel will be adequateto maintaincontrol. Manpower and time requirementswill be directlyproportionalto the number and size of the islets selectedfor control. If controlis requiredfor the base camps of Lojwa and Enewetakonly, then approximate seven - fourteendays will be requiredutilizingseven pest control persomel and one Entomologist. Control onmo,stor all of the isletsmay requirea mininwmof 21 people (20, 91’s, 1 Entomologist)and a period of 3 - 4 weeks. Accessibility to the islets by helicopterwould reduce the time requirements. NO specific control is requiredfor the wasps. However,certainprecautj are wan-antedfor personnelworking in thick foliage. Long sleevesand pants. No bright coloredor pastel coloredclotliingsuch as reds, yellows Insect repellents are of no value in protecting against.wasps and , Nests may be destroyedwith Wasp Kill or similarregisteredinsecticides as they are located, Personnelhow-n to be all&gic to insectvenoms should not be permittedtowork in risk areas as described.
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s. .. . small and not at a level which in anyway is to be considereda,.; problem. ..,.’ ,. to work as a comparativelysmall number of insectshave beensuccessfull . introducedon the atoll. It would be helpful if incomingcargo were: screenedto insure that new pests are not introduced. ,, b, Pest controlon any large,, other than the rodentsas.- scale is not requiredfor any animalor insect
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1.,, ‘Arthropods: - The taxonomic classification which includes - Insects, spiders, millipedes, scorpions; etc, Ectoparasites: Fleas, ticks, lice, mites, .etcs,’li-ving on ~ the bodY of a host organism such as a rat. Entomology: The study of insects.3. Examples would be trash dumps, Have-A-Heart Traps: A brand name of a rodent trap which catches the animal alive and without injury. Lepidopterous Larvae:. Moth and butterfly catterpillers.7. Musca: The genus of flies to which house flies belong.8. Polistes fuscatus Var. aurifer: A common variety of paper Polistene 1’ pe Sting: Typical sting of the paper wasp Fee Wheel ~lair Reaction). Prebaiting: Positioning a bait without the presence of a poison t- measure the acceptability and consumption by the rodent t be controlled. Furthermore, it indicates if other non-target organisms will be attracted to it. Predator: Usually an animal which specifically seeks out and destroys .another animal; i.e., cats to rats and mice. Ropalidia rnarginata: A common paper wasp similar to tbe A mud wasp which is predacious against spiders. orrrially,It does not sting man but is capable.. Vespidae: A. laqge taxonomic group of wasps which include the
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Wheel-Flair Reaction: A common local reaction to the of many wasps. One typically has a raised blanched center about 1/2 to 1 centimeter across surrounded by a large red circle with a common total diameter around’ the size of a to a half dollar.