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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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BEST COPY AVAIMBLE a. By the cljrectionof DASG a medical e?ko-ologicalsum’ey~iasconducted on selcctcd corol islets of the Env,wtakAtoll to determineall real and potential entomologicalproblems to be encounteredduring cleanup a fragile and unstablebiologicalcomnmity. Tk introductionof higher animal life forms has been artifici~.1.This sit~]ationhas allowed a number of species to inhabit the i~lctsuncheckedbY natural . c. A variety of factorshave successfullylimitedthe t!,eestablishment 1) Limited acces;abilityof the islets. 3) Limited land area, breeding sites, appropriatefood sources and d. These factors have, for the most part, restrictedthe establishment ; of medically importantarthropodaon the islets. k a. A total of 12 isletswere selected for surveillance.Selectionwas based on the followingcriteria: Vegetation and stmctuml harborage. Operationalaspects related to cleanupmission. civilians and natives. r“ Informationprovidedby engineers~u.weyj,]]g various islets.
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breeding sites und l}arboragc~lieresom~~lcd,]Jig}lttr~Ps\~~rcset out in areas u-herewind shelter~~’asprovided to sample nocturnalactivity. Rodent surveillancewas visual and with traps. llave-a-F1enrttraps equipment indigenom to the survey teams pro~~idedample work and scopicallywith the use of appropriatekeys. d. The followingisletswere surveyed: a. The predo,minanatproblem on the atoll is thelargepopulationof rats. Two spdcies of rats l~rerenoted,
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The total absence of natural predationon the’isletshas allowed the “ population to soar and-be limited only by populationpressure, “ P the exceptionof the islet of Ene’,~stakthe rat populationreached the “ Mice, though not taken in traps, a:e presenton t~leislets”“’”Eviden?e’~’””1. used to determine their presenceW-S the collectionof frass and ‘,- signs of dtamage.The populationof mice on the individml islets is”’.”.-~ obtain ectoparasitcsfrom the rats. -. 3) Visual examinationof the ‘bo+fand hair with the aid ofmao~ifying “ Lack of higher ectoparasiticpopulationis attributedto extremely. ,“ limited contactwith other maminalianspecies. Various species of stinging (aculeate)wasps are present on all of the islets. Polistes _ fuscatus-var.aurifer is the most aggressive. Ropalidiamarglnata Parasiticwasps of the family Sphscidaewere also collected. “b In all cases the wasp populationsper islet is low. However, where present the wasps tend to be concentratedin small areas. For example,on the islet of Jedrol (Rex) a P. fuscatus colony viable and nests varied in size from the diameter of a quarter to the size of a football. About 25wasps were present in the refrigeratorbuilding amda ‘~ number were observed foragingin the area. The estimatedliving populationof the colony is ben~een 100 and 150 wasps. . Limited natural food sources and high winds have severly restricted the numbers of wp.spscapable of survivingon the islets. Normal limited. Coloniesare thereforesmall anclfocal. They mayusuall} be located in dense foli~.~e,well shieldedfrom the wind and close to the ground. Sore;R. marginatawere observed nesting up tosix feet above ground on–thyl=e of the foliage.
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4) The wasps normlll.yare not ag~ressiveand CIOnot seek out or type stings with a wheel-flairreactionand pain lasting from , although some people recalledbeing stung 4 or s times.“One - - report OE 20 stin~s could not be confirmedantiis considered “ ~~ only no;iced when the integrityand safetyof the colony or ..;.: ; has been bitten by a mosq’.lito.High wj.ndsare the major factor Spiders are present thro~@out the atoll’s islets. Specimensof what appears to bc the block wjdo:{have been collectedby pcrsomel of have been sent to the Bishop ihs~ti~, Ilawii for confirmation. No “ other venor[lousspi.dcrsha~’ebeen reportedfrom or collectedfrom the Snakes are not present on EnewetakAtoll. Flies affecti;gman ~ppear limited to severalspecies of the Kenus breeding areas are in anclaround waste disposalsites. Populationsare small and of nuisancevalue. Some transmissionof entcric-diseases structural integrityof buildinss. The rodent populationsrequire control of the earliestpossibledate. Baiting with zinc phosphide is the most acceptableto this writer. However other baits arc ava~lablc. A s~cci:llamex to this renort will be 1 presence’of zinc phosphide to dete~minewhich is the most acceptable I to the rats. Upon completionof preba.itingthe actual zinc phosphide ~ bait should be employed. Each islet shouldbe prebait.cclimmediately - prior to baiting.
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Prebait and bait stationsshould be placed”ih the exact same locations., . of the baiting cycle. Unconsmed baits shouldbe retrievedwithiti48; 72, ~ hours of their placement tO limit contactwith non target organisms. “-,.. The process of cleaningup the islets by engineers~villitselfhive’”’”,’,:~. anclfood sources. This combined integratedcontrolshould significantly ~ reduce, but not bradicatethe rodent population. Continuedsurveillmce by certifiedpest controlpersomel (LIoS-91S,civilianor engineers). under the direct supervisionof a professionalentomologist. Thereafter’ number and size of the islets selectedfor control. If control is “’ f required for the base camps of Lojwa and Enewetakonly, then approx~matel$ personnel and one Entomologist. ,* Control on most or all of the isletsmay requirea minim~bf 21 peop~e ““” (20,’91’s,1 Entomologist)and a period of 3- 4 weeks. Accessibility ~. to the islets by helicopter\(ouldreduce the time requirements. No specificcontrol is required for the wasps. However, certainprecautic are warranted for persomel working in thick foliage. ., 3) NO bright colored or pastel coloredclothingsuch as reds,’yellows, 4);, Insect ~ellents are of no value in protectingagainst.waspsand be; tides as they are located. I
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to work as a comparativelysmall number of insects}~ave,beensuccessfully in~roduceclon the atoll. It would be helpful if incomingcargo were,..... ‘b. Pest control on any large scale is not requiredfor any aninal or in&ct
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Arthropods: ‘“The taxonomic class ifi~ation which includes the body ot a host organism such as a rat. i’ Entomology: The study of insects. .,.,.. 1’ 5. Have--A-Heart Traps: A brand name of a rodent trap which . 1P. . catches the an~mal alive and without ln]ury. The black widow spider. 7. Le~idopterous Larvae: Moth and butterfly catterpillers. 8. Musca: The genus of flies to which house flies belong. 9. p. fuscatus: See 10 below. .: 10. Polistes fuscatus Var. aurifer: A common variety of paper . 111.. Polistene I’pe Sting: Typical sting of the paper wasp 12. prcbaiting: Positioning a bait without the pres~nce of a poison to measure the acceptability and consumption by the rodent to be controlled. Furthermore, it indicates if other non-target organisms will be attracted to it. A common paper wasp similar to tbe 16. Sphecidae: A mud wasp which is predacious against spiders.. ...’ Normally, it does not sting man but 1s capable.. 17. “ Vespidae: A large taxonomic group of wasps which include the
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of ‘typically hasmany wasp5~xle a raised blanched center across surrounded by a large red ~~P about 1/2 to 1 centimeter . ,“~