Effects of carbosulfan and permethrin on fresh-water shrimp (decapoda. caridea): in southern Togo, west africa

;i.{ t ocp/vcu/nYBro/86 .17 ENGLISII ONLY EFFECTS OF CARBOSULFAN AND PERMETHRIN ON FRESH-WATER SHRTMP (DECAPoDA. CARIDEA) IN SoUTnERN ToGO, WEST AFRICA SUMMARY a. In enclosed lab tests, all insecticides. Mortalitles to the permethrin, CS = carbosulfan): by Bruce M. Wahle shrimp ln the treatment tanks were effected by the two lnsectlcldes were ln the followlng order (P = P 3Or = P 10r > CS 1or > p 5' > CS 5' > p 1'e 20 C > P lrG 25 C =CS I'G 25 C > CS lrG 20 C b) In fleld situattons, the shrirnp were, not greatly effected by the additlon of either of the lnsecticides. Larger doses of permethrin applied repeatedly did eliminate M. raridens from a stream (Everts et al. 1978). Normally the shrimp are retlring airfng Ea-ay and are not seen, but are actlve at night (Lewis "t "1 . Lg66,Ohno et al. L977, per comm. with Togolese locals). Wlth the applicaEions of lnsectlcide to bot.h rivers, shrlmp were observed after treatnent. Earlier (Interim Report), I had called this a behavioural change, but this is actuall-y the inhibitlon of acetylcholinesterase causing agltatlon and hyperactivity, the first slgns of pyrethrin and carbamate poisonlng (Albaugh L972), Takken et al. 1978, Shukla and Omkar L984, Omkar and Murti 1985, Omkar and Shukla 1985). We observed these actions in the early stages of the lab tests with the insecticldes. c) In lab test where the shrlnp could not escape, the lnsecticide caused greater signs of toxicity, (e.i., tetany, death). When the shrimp are unable to move theirgllls and the water in the tanks has probably less than l-00% dissolved oxygen, the shrimp may actually die from oxygen starvatlon. Whereas ln the river, the flow of the current may provide sufflcient oxygen to the shrimp untll thelr sytems recover, ln cases of mild intoxicatlon. Investigators feel thaL Lhe tetany ls not the actual cause of death for the shrlmp (Salgado et al. l-983, Omkar and Murti 1985). d) The purpose of thls contract was to gal4 lnformation about the effects of two alEernate insectlcides that will be used lf reslstance appears to temephos, the main Simullum larviclde ln the OnchocerclasLs Control Programme treatment area. The lEoratory test whlch the trilo lnsecticides demonstraied a high shrLmp toxiclty. The rlver tests we dld showed that, at larvicldal coneentrations, a minimum impact onjuvenlle to adult (TL-22-L27 nm) Macrobrachium vollenhovenli could be expected. Other investl.gators(Bridges1961,sand)reportedthattoxic1t1es were higher ln field than lab sltuatlons. This specles probably reproduces success- fully ln freshwater as do some other Macrobrach{um specles (Maclolek 1972, Wllliamson L972, Lee and Fiel-der L979). A wlde ;€nge;GLres of shrimp were present in the MonoRiver dralnage and recenEly fertillzed females were collected with spermatophores attached. We dld not colLect zoeal or postlarval stages becauses we were not looking for them and we had a larger mesh net that would not have retained them. The placement of dams has caused the decllne of some Macrobrachlum species, whlch require a return to more saline waters for breeding from arG-aToliiJ-llE dams (Ilorne and Beisser Lg77). I'{. carclnus is one specles that needs to reproduce Ln estuaries, but has not ocP/vcu/HYBr0/86 .17 Page 2 had lts range reduced by darns. IE is reported to readily Leave the water (Ilorne andBeisser L977). M. vollenhovenil Ls reported to leave the water by Togolese locals.Macrobrachium australiense were observed making a six meter vertlcal cllmb over a dam reisadamontheAmoutchouRiverbetweentheEwospots where we collected. Shrimp were present both above and below this dam. If the adults dohave to return to the sea to reproduce, the dam under construction at Nganbeto, Togo is much more of a threat to the upstrean migratlon of shrlmp to the upper Mono Riverdrainage than the spraying of these lnsectLcldes in selective sections of the dralnage.M. vollenhovenii ls one of the speciess of Macrobranchium that produce many, small eggE. ttrrffihruon or non-abbrevtated p.r""*""idae developmentar type that produces nany offspring that pass through nany zoeal stages (Sollaud Lg23). st"ares by Bluzat and Seuge (L979) found that concentratlons of Carbaryl that the adults of Lymnaestagnalis could llve in, were lethal to the young snails. The effect of peGffi?tn and carbosulfan ls unknown on the larvae of M. vollenhovenil. The spawning season appearsto extenred, as ir ls la Liberia (May to-JanGs@r 1971): The inrenrlon of ocpis to spray the main river on1y. Smaller streans w111 act as refugia for repopulatlon, as well as migration back into the sprayed area from up and downstream (ltaciolek L972,Lee and Fielder L979). Previous exposure to lnsectlcides provldes a higher resistancein Procambarus acustus to later exposures (Albaugh Lg72). ialearnonetes kadlakensis alsostroffiithcarbamatel.nsectic1der(N;q;i.,"." stagnalis exhlbits a tolerance to carbaryl (Bluzat and seuge LgTg)o e. Some shrirnp nolt skins were found after the second treatment. The only tlme molt sklns were observed, in alL the river surveys ln Togo, was after the insecticidetreatements. Moltlng during laboratory insecticide tests rras considered due to thestress of captlvlty (Ahsanullah L976, omkar and Murtl 1985). Molt skins were observedonly a few times, but only after permethrin (1) and carbosulfan (3) treatment. Fowleret al. (L975> found that 92-1ooZ of pluEonium ln crusEacea rdas lost with the molted exoskeleton, and another study found that 927. of neptunlum-237 was in shrimp exoskeleton (Guary and Fowler 1978). However, only OZ ot the plutonlum, in Cancerpggurus,_in a study ln the natural environment, was found ln the exoskeietonlG?y etal' L976). Possibly the irritatlon of the insectLcide, may induce shrimp that are ina stage cl-ose to moltLng, to molt earlier, in an effort to rtd the body oi ttreirritatlon chemical-. f' In the Mono and Anie Rivers there are many of mussels and freshwater oysterspresent. These sesslle organisms could act to concentrate insecticldes that are repeatedly applled to stream sectlons in an effort to control Simulium 1arva1populatlons. These molluscs are a popular food source wtttr toETffiie and are easierto collect than shrlrnp. After the last two weeks of carbosulfan treatment recently dead mussel sheLls were notlced ln the treatment area. These may have been natural deaths orthey nay have been harvested and cleaned by humans. PURPOSE OF VISIT 1. The purpose of my contract, as stated in a letter of 6 August 1985, was "evaluation of effects of insecticldes on freshwater shrimp and other Lnvertebrates". On further dlscusslon wlth Laurent Yam6ogo ln Ouagadougou, Burklna Faso, three projects were outllned to be done sLmultaneously deaLlng only with freshwater shiimp: 1) a rlver survey of southern Togo to locate shrimp populations, and to locaEe two rivers wlth adequate sections for observlng the effects of pest,icldes on freshwater shrinppresent; 2) colLect Large numbers of shrimp and transport them back to the laioratoryto test two insectlcides (carbosulfan, permethrin) ln tank tests; 3) apply a "standard"dose of an lnsectlclde (carbosulfan O.O5O ppm/lo minutes, permetnrfn O.Oli ppm/fO minutes) once a week, for four weeks, to each rlver sectlon and observe the Lffe"t" o.,freshwater shrimp. Freshwater shrlmp are an lmportant part of lotlc ecosystems(Truesdal-e and Merrnil-liod L979, Ilart 1980) and thus the onchocerciasLs Control Programme Ls Lnterested in Ehe effects of thelr lnsectlcldes treatments on these organisuns. The work in Togo took plaee from 14 November 1985 to 13 December 1985. rt 1) J l OCP/VCU/HYBIO/86 .17 Page 3 PROJECT AREA 2. The study Eook place in southern Togo, West Africa. Seven rlver slEes suggested, by the Ouagadougou office, to survey on four rivers: Anie River (Akaba, Blitta, Pagala), Amou River (Amou-Ob1o), Mono River (Tchamba, Landa-Mono), and Wawa River(Djodji). Addittonal sites qrere sampled by myself ln an effort to locate shrimp populations. A complete descriptlon of each site is given in section "RLver survey". The project area is bound on the north by the Tchamba slte (-9 Or N., L 26' E.), on the south and east by the Tetetou site (-7 0r N., 1 30 E.), and on the rf,est, at the Ghana-Togo border, by the Djodji site (7 361 30" N., O 35'8.). FINDINGS 3. The results from t.hls short term contract provlded four sets of separate information. These are each discussed below in separate sectlons: rlver survey, shrimp species present, laboratory resulEs and rlver tests. The Harmattan arrived 3 December 1985, causing the temperature to drop appreciably for several days. River survey River Survey of Southern Togo 4. The river survey was done with two purposes in mind: 1) to locate rivers with sufflclent river shrlnp populaEions to collect for laboratory tests of insectieides; 2) to locat.e two rLver sections, with rlver shrimp, that would permit the observation of the effects of two insecticldes applied once a week for four weeks. In addition to the river sites suggested by the OCP office in Ouagadougou, I vislted other sltes ln the area ln an effort to locate adequate populatlons of rlver shrimp. 5. Shrimp presence was assessed by asking the local people whether shrimp were present, vlsual observaEion for habitat sultability for shrimp, and electro-fishing. Electro-fishing was accompllshed using AC current from a small generator (Honda Portable Generator EX50O, 6O Hertz) or a large generator (Honda Generator E15OO, 50 Hertz). The larger generator r.sas more efficient Ln collecting shrlmp. The rivers observed could be divlded lnto two categorles of catch per unit of effort, uslng the electro-fishing equipment., two men, and one dip-net: low (O-10 shrtmp/hour), or high(30-100 shrfunp/hour). Seinlng and trapplng was al-so atteupted, but could not be realistlcally counted on to provide shrimp in sufflcient quatitles for 1ab rests. Addltlonal shrimp specluens were provided by two other investigators working ln the area at. the same tlme (Bass, Benech). Latitude and longitude information was obtained from maps of Togo (1:20OrO0O, 1:50O'OOO) and Anonymous (1966). A descrlption of each slte is listed below. I Mono River Drainage, Togo Amou River 6. North of the town of Amou-Oblo, Togo (7 24'N., O 52t E.). Electro-flshlng showed shrimp and crab present, in low numbers. Insects, -frogs, snakes and fish present. Water uoderately fasE and clear, depth upto -1.3 m. This was chosen for a rLver test slte, It aPpears to be a spring-fed st,rearn that changed 1ltt1e ln flow during our four week study, except after rains. The area ls a laundry and bathing area for locals. Sarnpled L5-16, 2L-23, 28-38/xr, 5-7, L2-L4lXrrl85. 7. North of present. Sand mean depth 0.5 the town of Glel, Togo (7 2OrN.,1 10t E.). A large populatlon of shrimp(rnajority), boulder and bedrock bottom. Maxlmum depth -1.4-1.5 m, and m. Current moderately fast and water clear. Gastropoda (Thiaridae fish present. Sampled. 6-7/XII/85 by electro-flshing.Potadoma sp. ), Amoutchou River 8. AmoutchourTogo (7 23' N., 1 1lt E.). Electro-fishing shrimp. High turbidlty, and mostly deep. A dam is located 9 lxrr/8s . ? ocP/vcu/HYBTO/86 .17, Page 4 collected sma1l numbers of usptream. Collected 1ocals or electro-flsh. Sandy pool area. One crab seen. 9. Ebeva, Togo (7 32' N., bottom, poor looking habltat Visited 22/xr/85. Anie River 1 6r E.). InIe did not talk to around the bridge, and a deep 10 Akaba, Togo (7 57'N.,1 2t E.). Locals say shrimp present and electro-flshlng confirmed this. Bottom mostly sand wlth gravel, cobble, and boulders. VLsibility poorin deeper pool area. This was chosen for a rlver t.est site. The reach is a laundry andbathing area for the locals. fish, snakes, freshwater oysters, mussels, crabs, frogs, and insects present. sire sampled 17, L9-21, 26-29/xr, 3-5, Lo-L2/xrr/g 11. Blitta, Togo (B 19'N., o 59r E.). Locals say a large and sma1l species of shrimp present. Mixed substrate of sand to bedrock; habltat looks good for shrlmp.I{ater visibtlity good in shallower areas, depth to -1.5 m. River too deep an6 visibillty bad overall for a river resE. visired 14, 17/xr/85. L2- Pagala, Togo (8 llt N. o 58r E.). River too deep and vislbiliry poor for rivertest.. Locals say a large and small species of shrimp are present. Cichlidae(Hemichromis fasciatus, upxo 22 cm) and pelecypods present. Vislred LTIX1,/85. 13. Exact location not given, Kra or Gare, Togo (-7 10 N., 1 lOt E.). Two shrimp were supplied by Dr Benech, which he collected whlle gilI netring fish, 6/XII/85). Mono River L4. Atchinedji, Togo (7 site, 5 December 1985. 34t N., L 2L'E.). Two shrlmp provided by Bass from this 15. Landa-Mono site, between Sessara and Diome, Togo (-8 4Or N., 1 13t E.). people say only a few shrimp present (-50-60 nm). Stream falrly fast and deep, and very sandy. Fish, freshwater mussels and oysters present. Not chosen for river testing slte because stream visibility poor, the l-ong distance from Atakpame, dlrt road travel sI-ow, and road construction on-going. If the water leve1 decreases, this would be agood tesr site. Visited 17 November 1985. L6. West of Tchamba, Togo (-9 O? N., I 26t E.). Substrate mainly (85"/.) sand, somegravel and bedrock. Local people say no shrimp present. Habltat looks poor for shrimp. Visited 14 November 1985. 17. Tetetou, Togo (-7 198s. Oule River or N., 1 3Or E.). One shrlmp provided by Benech, 5 December 18. Ezime, Togo produced a few of a population this was (7 29? N., O large speeies. not pursued as 56r E.). Locals say Habltat looks good, a collectlon site. shrlmp present. Electro-fishing but because of the low Sampled 22 November 1985. ocP /vcu /HYBTO/86 .17 Page 5 Asukawkaw River Dralnage Wawa River 19. Djodji, Togo (7 36t 30" N., o 35r E.). rn Togo this is referred to as theGban-Hou River, but changes to the wawa river in Ghana; it is known as the Wawa rlverat thls point. The bottom is a mixture of sand to bedrock substrate, with a 1ot of overhanging and inundated vegetation. River clear, fast, upto 1.5 m depth. Water chemistry taken with a llach Chemical Klt showed: pH 7.5r-haidness 34.2 rg/f,phenothaleln alkalinity o, nethyl orange alkaliniiy 68.4 rlc/L. Electroshocking equipement worked well in shallower water (both g"rr""rto""j. Large populatlons ofshrimp present ln main river and small site stream. Flsh, Lnsecte, crabs, gastropoda(Pllidae, I1]l-"n.) were present. we collected shrimp from here for the laboratorytests. Sampled 18, 25 November, 2 December 19g5. Shrimp species present in Southern Togo 20' Three species of freshwater river shrinp (Decapoda, Carldea) were identifled fromour extensLve survey and additional data provided by Bass and Benech. These are theAtyidae, Caridina afrLcana, and the Palaemonidae, Macrobrachium sollaudil andMacrobrachiumvo11enhovenii.Carid1naafri-canaaniwereonIy "rffir"J. "ioi.">,and all specimens collected ln the Mono River drainage were Macrobrachium vollenhovenii. 2L. Shrlmp species were identified using tlolthuis (1949), Miller (1971) and Monod(1980). Lengths were measured using r..ri"., with 1 mm divislons. Total length was measured from the posteriormost margln of the orbit, at the base of the eyestalk, tothe posterior edge of the uropods. carapace length was measured frou the posterlormost margin of the orbit to the dorsal-posterior edge of the carapace. Dorsal and ventralteeth on the rostra were counted by eye or dlssectlng microscope. Egg measurements were determined with a ruler wlth 1 nm divislons and a dissecting microscope. Shrimp were preserved in 80% a1coho1, and measured wlthin 29 d,ays. Because of tinelimltati-ons, the shrlmp were not sexed or welghed, and not all M. so1laud1i andcari.dina africana were measured. The specimens are retalned rn-ttrEffiTEtor control@ ouagadougou, Burklna Faso. Caridina afrlcana Klngsley 1882 22. This species ls rnainly present in aRiver, but lE was also col_lected from the at this site. It keys out rdell ln Monod rosEral teeth 6. The total lengths of the mm. Ovigerous females, 17-19 mm. slow moving side-stream taht enters the l.Iawa main river. It is present in large numbers(1980). Dorsal rostral teeth 21, ventral specimens measured (n = 20) were from L2-2O Macrobrachium sollaudli (De Man) 23' This species was collected mostly in the main wawa river, but was also present inthe side-stream. rt ls present in large numbers at thls slte. rt is not listed lnMonod (1980), but is descrlbed ln Holthuis (1949). The rostrum is stralghter andbroader towards the tip, than M. vollenhovenli. The rostral dorsal tooth count ls g(7-11), and ventral counE 2 G=3)-G-=B);The rorat lengrh (n = 101) was from tg ro62 mm, and the males were larger than the femaLes. Ovigerous females were from 45-46mn (n = 4). The eggs were round, large (2-3 mm), and few. This type of egg isdescribed by Sollaud (L923) in the Palaemonldae as "abbrevlared- (i:"., triir,!-t.ru. and larger eggs wlth many zoeal stages ellminated). Thls river eventually drains intoLake Volta, and this populatlon probably completes its 11fe-cycle in freshwater. ,oc.P/vcu/HYBro/86 .17 Page 6 Macrobrachlum vollenhovenli (Herklots 1857) 24. This was the only species collected ln a wide ranging survey of the Mono River drainage. Specinens lf,ere collected by electro-fishlng, trapping, g111 nettlng, and hand capture. It was usually present ln low numbers at the sites I sarnpled. According to informaEion given Jon Bass (personal communicatlon) by the local people, the lowest numbers of shrimp occur during November to January. This large specles ls commerclally important in Senegal (Gruvel 1908), Guinea, Ivory Coast, Gabon, Congo, (Gruvel L9l2), Benin (Monod 1966), and Liberia (Miller L97l). Holthuls (1980) said that due to its occurrence ln low numbers, it probably never supports a large flshery. In Togo, this speeies is reported to show up in the market occaslonally ln Atakpame and Anie, selllng for approxlmately 100 FR CFA/60-100 grammes. It is captured by the local- people for thelr own use. 25. The specles keys out well in Monod (1980). The rostrum has 13 dorsal teeth (12- 18) and 4 ventral teeth (2-7) (n = 115). Shrimp we captured had total lengths from 22 to L27 (n = 115), but we had a wide mesh dip-net. The rostrum is expanded towards the tip, and the tip is slightly upturned. One ovlgerous female was collected, wlth many, smal1 (( O.S nrn) teardrop-shaped eggs. This developmental type is known as "common" or non-abbreviated (i.e., many srnall- eggs and larvae which pass through many zoeal stages)(Sollaud L923). Miller (1971) found females wlth eggs ln the advanced stage of development from May Eo January in Liberl-a. This long reproductlon period would explain the wide size distribution. The males grow larger than the females. 26. Although a habitat study rdas not an intended part of thls work, many rLvers rrere sampled in the Mono River dralnage looking for adequate shrimp populations to collect for lab studies, many methods were tried, and many 1ocal people were questloned. Smal1 shrimp (TL 22-39 mm) were collected from clear, shallow (10 cm) raplds, with gravel bottoms and river edges wlth sand bottorns and vegetatlon. Juvenile shrimp (TL 40-84 mm) were collected from l-ess clear, deeper waters (1-70 crn). The largest shrirnps (TL 9O-L27 mm), we captured, tend to move to the deeper pools, but were also collected and observed in shallow water. They require something to hide under, and were sometimes collected around boulders in deeper raplds. Laboratory tests with carbosulfan and perrnethrin on Macrobrachium sollaudil, M. vollenhovenii and Caridina africana 27. River shrimp were collected from the wild and transported by truck to the OCP l-aboratory aE Atakpame, Togo. A11 tests were conducted with shrimp collecEed from the Wawa River, with the exception of one test. (9 Decenber 1985) after a large number of M. vollenhovenii were collected. The najority of shrimp tested were M. sollaudll, @ afrlcana were usuall-y present. The shrimp we?e correctea uyelectro-fishing. The were transported back to the 1ab in large tubs half fllled with unaerated rlver water, a two hour trip. Extra river water was brought back in glassjugs. The shrimp were rested i.n aerated water ln the laboratory from 19 hours to 8 days (usualLy 2 days) before a test was run. AeratLon was provlded by stone diffusers. At Atakpame, there ls no electricity every day from O5:OO to 1O:OO hours (wlth sporadic black-outs at other tlmes). A generator supplled electrlclty to the laboratory during thls perlod, however lt was not usually started by the staff untll O6:00-06:30 hours. Water temperatures were measured with a hand thermometer. The tests were conducEed on the floor in a congested area of the lab. ocP lvcu lHYBro/86.17 Page 7 28. Laboratory insecticide Eests were conducted ln 1O 1lter plasLic (type unknown) tubs. No attempt was made t.o fllter the river water for Ehe tests. although the water was always settLed, the amount of suspended partlcles varied from test Eo test. The river water was always at ambient temperature. The water warrned up slightly from the river sittlng in the lab. The tests where the water temperature was cooler were due tothe arrival of the llarmattan, reduclng the air temperature. No food was given to the shrimp durlng the tests. The number of shrlmp used for the lab tests ranged fron 19-30per tank, dependlng on how many we had available. Equal numbers of shrimp were placedin each tank (control, test), with 5 llters of rlver lrater. The desired quantit.y ofinsectlcide, permethrin (o.o15 ng/1) and carbosulfan (o.05o mg/1), was added to the test tank by plpette, and mlxed int,o the water. The shrimp remained ln this solutlon, wit.hout aeratlon for the duration of the exposure (1, 5, 10 or 3O minutes), At the end of the time period, the solutlon was poured through netting to capture the shrlnp. These shrimp were then put in a fresh tank of aerated, river water and observedperiodleally for 48 hours. A serlous problem was the loss of shrimp due to otherfactors (Jurnping out of the tanks, cannibalism) than the lnsecticlde. Cannibalism Ls aproblem wlth crayfish and river shrimp studies (Miller, L97L, Jolly et al. 1978b, Truesdale and Mermilllod L979). To stop the shrlmp from jumplng out of the tanks, various tank covering were used (papaya leaves, banana leaves, a 2nd tank). Because of other tasks that requlred that we be out of the lab, the observation tlmes occurred at odd tlme Lntervals. Shrimp rdere usually observed for the first two hours after atreatment, at 24 and 48 hours. Dead shrimp were removed and recorded, as they were observed, and preserved in BO% a1coho1. A shrimp was considered dead when it showed no movenent and did not respond to gentle prodding. Moribund shrinp were eonsidered to be those shrimp that sti1l were alive, but did not respond "normally". This represents a condition from a shrlmp laylng on iLs side with only one appendage feebly moving, to a shrimp Ln normal standlng positlon but not moving around or responding to movementsdirectly above lt by the observer. "Normal" shrinp would move around or dart away from overhead observation (Shukla and Omkar 1984, Omkar and Shukla 1985). The test \,ras termlnated at 48 hours or as soon after thaE as we could return to the lab. At the end of the test, the shrlmp that remained alive were ki11ed and placed in B0% alcohol. The test tanks washed with laundry detergent and air dried. 29. A series of nine tests \rere run; the availabllity of shrimp was the limiting factor. Each test is described brlefly. The results are summarized tn Table 1 and 2. 30. Test 1. Run 21 November 1985 wlth Permethrin 0.015 mg/l for 1o minures and 3O minute[IEEr temperature 25.5 C. A mlxture of Macrobrachium sollaudii and Carldlna afrlcana was used frorn the wawa River, with l^Iawa ffi.ffiil- Effiffi leere cofG?I6l-18NovfiEer 1985. The control tank trad ihrtrnp with a roral lengrh (TL) of 16-43 mrn. In the 1O mlnute tank (TL L6-52 mm), after 5 minutes the larger shrimp were agitated., Jumping around, and losing coordinatlon and lying on their sldes; after 1-O mlnutes, after transferal to the other tank, all were moribund or dead. In the 3O minutes tank(TL 14-54 nm), after 15 mlnutes, all shrimp were morlbund or dead, after 37 minut.es aL1 aPpear dead. The test \ras prematurely ended after 10.5 hours due to a language communlcation probLem between myseLf and my lab assistant. 31. Test 2. Run 27 November 1985 with carbosulfan O.O5O mg/l for 5 minutes and 10 ninute[ilTer temperature 25.5 C. A mixture of Macrobrachium sollaudil and Caridlna afrtcana was used from the wawa Rlver, wlth tla*a ffi.:Iil shrirp ,r.re coffi25 November 1985. In the tank of 5 uLnute exposure, after two minutes shrlmp (and couple of flsh that were added) were affected, and shrimp were jumping out of the tank; after5 mlnutes all shrimp were morlbund; afEer L7-35 minutes all but 2-4 shrlmp seemed to have recovered; after one hour deaths started to occur; by 2L hours 45 minutes all flsh were dead. In the 1O minute tank, after 1O minutes all shrlmp (and added fish) were moribund, by 46 hours all the fish (3) were dead. At 45 hours 5 minures, all remalning shrimp ln the control tank were dead. I belleve thls was caused by residual pesticidefrom the tank of airstone. a, oc? lvcu lHYBro/86 .17 Page 8 32. Test 3. Run 4 December 1985 with carbosulfan O.O5O mg/l for one minute and permeth-m-b-.015 mg/l for one minute, water Eemperature 20 C. The water was very turbid. A mixture of Macrobrachiurn so11audil and Caridina africana was used from the Wawa River, wlth wawa ffiJGE- ffi'p were coffi2lA6EAr 1985. rn the carbosulfan tank, after 8 minutes the smal1 shrimp were very active, after 32 minutes they settled down and acted "normal" until the end of the test. In the permethrin tank, the shrinp were acEive and trying to leave the tank for frorn B to 31 minutes; shrimp started becoming moribund after one hour and remained effected until the end of the test, deaths began to be recorded after 7 hours. 33. Test 4. Run 9 December 1985 wlth permethrin 0.015 ng/1 for 5 minutes, water tempera=EliE-2s.5 C. Macrobrachium vollenhovenll from the Amou River were used, with Amourl.verwater.sember1985.After1m1nute,theshrimp were jumping around the tank. After the transferal- after 5 ninutes, all morlbund. They never recovered, although some were showing some feeble signs of Life after t hour 5 minutes. 34. Test 5. Run 1O December 1985 with permethrin 0.015 mg/l for one minute and carbosffii-o.O5o mg/l for one minute, ,ri"r temperature 25 C. Macrobrachium sollaudll fromtheI,IawaRiverwereused,withAmouriverwater.Shr1mpweE-ffiI--2DeceEber 1985. The control tank had shrimp wlth a total length from 26 to 46 mm. In the permethrin test (TL 19-62 nm), after 15 minutes about 40% of the shrlrnp were moribund, after t hour 34 mlnutes all but a couple of the shrimp were moribund, at the end of Ehe test one sma1l flsh in the tank was sti11 alive. In the carbosulfan test (TL 22-45 nm) after one hour 16 ninutes, a few shrimp were moribund and some were jumping around. From t hours Eil1 the end of the test, the remalning shrimp that were alive acted "norma1". DISCUSSION 35. The shrimp reacted to both chemicals similarly wit.h agit.ation, jumping around and trylng to leave the test container, loss of coordination, paralysis, and death. This follows the course of events reported in similar tests with crustacean specles (Albaugh L972, Takken et al. 1978, Shukla and Omkar 1984, Omkar and Murtl. 1985, Omkar and Shukla 1985). In the enclosed space where they could noE escape, all shrlmp were effected by Ehe additlon of the l-nsecticlde. Both chemicals formed a whltish emulslon, so Lt was not posslble to see all movements taklng place in the tanks. The shrimp became agltated and jumped around the tanks, trying to escape from the chernical. Depending on the length of exposure, when the shrlmp were transferred to clean water they were agitated and trying to leave the tank to moribund (not rnoving, ususally lying on thelr sides, but sometimes in an upright poslt.ion. The lrritatlve actlon of the pestlcide had a rapld effect on the shrinp. The insectlclde appear to cause a paralysis resultlng ln death. The shrimp dle on their sides with thelr tal1 curled up, other times they die paralysed in a "normal" uprlght positlon. 36. The results from the 1ab tests are summarlzed ln Table 1. When calculating ruortalities (Tab1e 2), shrlmp ln the morLbund column have been combined with the shrlmp ln the dead column, under the assumptlon that moribund shrimp will not survive. The mortalities have been calcultated includlng both the missing shrimp and not lncludlng the misslng shrimp. It could be argued that the shrimp dled'or were weakened as a result of the insecticlde, and thus were eaten, or they were effected by the insecticide that they jumped out of the tank and would have become moribund later if they remained. The other assumption ls that al-l missing shrlmp would have lived. ocP lYcu /HYBTO/86 .17 Page 9 37. The permethrin results graphically shown in Figure 1, clearly show a decreasing rate of morEalLty wlth decreasing tlme exposure: 30r = 10r ) 5' > lrG 20 c > l'G 25 C Other lnsecticide studies have stressed lncreased toxicity wlth increased exposure time(Shukla and omkar 1984, Omkar and Murti 1985, Omkar and Shukla 1985). The morraliries in permethrin treatments with misslng shrimp ineluded are 1002 and 851l, and without misslng shrirnp lOO% to 802. The control mortalltles with missing shrlmp lncluded are 37% to O%, ar.d wlthout mlssing shrimp 71[ to O%. The one minute tests varied in temperature and degree of turbidity of the water. 38. The carbosulfan results (Figure 2) also show a decreasing rate of mortality with decreasing time exposure: 10'>5r>l'G 25C>1rG 20C The mortalities in carbosulfan experlments with nissing shrlmp lncluded are 1OOZ to 53"/,, aad, without misslng shrlmp included are 1O0Z to L311. The control mortalities with mlssing shrimp are 37% (LOO% lf considering the contaminated control tank) to 4%, and without missing shrinp 9Z (52"1, with contamlnated tank) t.o O"l. Permethrin O.O15 ng/l per one mlnute at 25 C and carbosulfan O.O5O ng/l per one minute aE 25 C had approximately the same rate of mortality for the shrimp. The toxlcity of the permethrin treatment for one minute at 20 C rnight have resulted from an increasedtoxicity due to lncreased suspended sollds or from a decreased temperaEure. 39, A11 shrlmp in the tanks treated with the lnsecticides appeared to be effected to some degree and the action was rapld. Mulrhead-Thompson (1970, 1978) reported that permethrin had an irritatlng actlon on Simuliurn larvae wlthln a few minutes, even at sublethal doses. Mulla et a1. (1978) reporE.a-that permethrin acted wtthin 5-10 minutes on mosqulto larvae. The shrinp, after sometimes appearLng to recover, wouldlater become moribund and die. Albaugh (1972) found that the majority of his insectlclde deaths of Procambarus acustus occurred L to 24 hours after exposure.Permethrinreadi1yadsffiie1andisnoEeasi1ydesorbed(Sharonand Solomon 1981) and the possibillty exists that it may be adsorbed onto the exoskeleton, and from t.here may continue to be absorbed Lnto the body after the lnsecticide solutlon has been removed (by changlng test t.anks or flushlng of the dose downstream). It also readlly absorbs onto particulate matter (Muir et al-. L979 ). Jo1ly et al. (1978 a) reported a permethrln 96 hour LC5O of O.O0O39 ^e/t for 8-12 mm (newly hatched)Procambarus clarkil and O.00062 mg/1 for juvenll-es of 20-30 mm. Muirhead-Thompson @hourLC9o-95,aft'eraonehourexposure'forGammaruspup1exof 0.001 ng/l. Permethrin letha1 toxlcity to ral-nbow trout varies inv@TiE[-ILter temperature (Kumaraguru and Beamish 1981). 40. Llttle work has been done wlth carbosulfan to date. Previous work focused on carbaryl and carbofuran. A 96 hour LC5O of 0.5 mg/l, for both carbaryl and carbosulfan, was rePorted for Procambarus acutus aeutus (Carter and Graves 1973). The 96 hour LC50 of carbaryl for pala;;;ffi ;@€ was <o.L2 trte/L (Navql and Ferguson 1g7o,Chaiyarachetatffi24hour..'a4Bnouil.c5oorio.oozmg/ifor Penaeus duodarum was reported by lowe (197O). Carbaryl and carbofuran are generalJ-y ffirytoxtctocruStaceans(Cheaheta1.Lg7g).Carbosu1fan1s approximately eight times less toxlc to rats than Carbofuran, and Carbosulfan is mainly metabolized to Carbofuran by the house fly (Marsden et al. 1982). Carbamates are reversible lnhibitors and other sltes and actions are the posslble cause of death(0nkar and Murrl 1985). ocP/vcu/HYBro/86 .17 Page 1O 41. Both permethrln (a synthetic pyrethrin) and carbosulfan (a carbamate) are acetylcholinesterase inhlbitors (Millet 1976, Marsden et al. L982, Omkar et Murtl 1985). Permethrin ls a type I pyrethroid (Narahashi 1980) lnsecticide, which causes extensive repetltive firing in many types of nerves. This causes symptottrs such as hyperactiviEy and uncoordinated movements, and 1s Ehe probable cause of rapld knockdown; "but it is poorly if at all correlated wlth toxielty" (Salgado et al.1983). Camougis (1973) reported that pyrethrins caused excltatlon then a block of activlty ln insect and crayflsh nerve preparations, and thaE this block was responsible for the terminal symptoms of "paralysis". But long after this "paralytlc" state has been reached, f1y motor units were active (Miller and Kennedy 1973), this paralytlc state has been called tetany and can be applled to most caEegories of lnsecticides, except for large overdoses (Mi11er and kennedy L972). The actual cause of death for most insectlcides ls unknown for insects (Mlller 1976), and the "blochemlcal mode of the actlon of the insecticides of the pyrethroid group remains almost unknown" (Bounias et a1. 1985 ) . River tests River test with carbosulfan and rmethrin on Macrobrachlum vollenhovenii 42. The Anie River by Akaba, Togo was chosen as the site to apply carbosulfan and the Amou River by Arnou-Oblo, Togo was chosen as the site to apply permethrin. The ehoice of which rlver to apply perrnethrin to, and which to apply carbosulfan was random. 43. Stream dlscharge was determined by measuring stream cross-sectlonal area and velocity at a point of steady flow. Stream width was determlned by measuring the width frorn bank to bank wlth a long rope, and using a small measurlng tape to measure the rope. The stream depth, at. Lhe same cross-section, was measured r.rlth a po1e, and the depth measured from the pole with the measurlng tape. The depth rdas measured aE a number of points to calculate a mean stream depth. Veloclty was at first calculated using a fLoat (orange) over a measured section during a t.imed passage, rnultiplied by O.B5 for a roughness correctlon factor. During Ehe second week a current veloclty meter I requested from Ouagadougou arrived. No lnstructlons arrived wlEh it, but my 1ab cechnician assured me that he knew how Eo use lt. Since OCP owned current meters, I assumed that their use was "standard" for current veloclty measurements, and switched t.o uslng Ehe current meter. It turned out the lab technician did not know the entire procedure and, as a result, a multLplicatlon factor of 2.6 was not applled. The resulting discharge calculatlons are approximately 38% of the actual values, thus the t.reatment is approximately 387" of. the desired dose. I^later temperatures \{ere measured with a hand thermometer, approxlmately 1O cm below the surface. Stream sections were measured by my paclng off the distance (1 pace equals 35 lnches, 1 meter equals 39 inches). 44. The steps taken were: 1) to deEermlne the dlscharge of the river; 2) determine the amount of active ingredlent (ln grarns) of the insecticide needed; 3) determine the amount of stock solution (in mllliliters) needed to deliver the desired amount of active ingredient. The amount of lnsectlclde to use was calculated wlth a formula rnodifled from ArmLne (1983): grams actlve lngredient = flow (1/s) x 6O (s/rnln) x (no. mln) x dose (micrograms/1) 1,Ooo rooo 45. The carbosulfan sotck solution was 250 grams of actlve ingredient per llter, manufactured by Marsha11. The Permethrin was 2OO grams of active lngredient per 11ter; the manufacturers name was not supplied to me. The lnsecticlde dosage was measured out, by graduate eyllnder or plpette, and dlluted to 5 1lters with rlver water. Both ocP lvcu/HYBro/86 .17 Page 11 lnsectlcides were applied by pouring the solution, from a 5 llter plastic bottle. I walked across the river, back and forEh, pouring the solution as slowly as possible untll the bott,le was empty. The bottle and measuring equlpment were then washed ln the stream at the same polnt. The lnsecticide was applied ln the nlddle or in the tall of a riffle. The effects on the aquatlc fauna were then observed for approximately 3OO meters for two hours. We returned to t.he sites at approximately 24 and 48 hours to observe the sections and talk to the loca1 people. Local people were asked to not bathe or collect water in the test slte area for t.wo hours, after we had treated the river. 46. The original intention was to apply carbosulfan O.O5O ng/1 per 10 minutes to the same section of a rlver for four weeks, and perrnethrin 0.015 mg/l per 1O minutes to another river for four weeks. Because of the change ln velocity measurements, the desired dose was only applied the first week (Table 3) or the flrst two weeks (Table 4), to their respective sites. The correct discharge is shown ln the tables, along\rith the actual dosage app1led. Nevertheless, shrimp (and other organlsrns) were kllled by the lower doses. 47. Although the effect on shrimp was the object of this study, we observed the other organisms in the rivers after treatment. Some of the other organisms effected were collected and identifled (Daget et Durand 1981, Demoulin 1981, Dethier 1981, Forge 1981' Philippon 1981, Harper and Stewart 1984). The tests at each rlver are discussed in detail below. Permethrin River Test 48. The slte selected for the permethrin river test was the Amou River approximately 200 meters downstream from the road bridge crossing 1t. The section ls essentially straight, with two rapid-pool complexes. The insecticide was applied in a rapide. The sectlon could be waded from O-79 m and 250-3OO m; from 79 m to 25O m it was too deep to wade and the edge too choked with rlparian vegetatLon for observatLons. Most attention was paid to the stations at 5O , 79, and 250-3OO m. The area between O to 45 m is a laundry and bathing area, and frorn the third week on, gravel was being removed, from the stream bed in this area for constructLon, by the local people. 49. The river looked llke good habitat for shrimp and large shrimp were collected and observed here, but with electro-flshing (both generators) only a few shrimp were collected here. Unseasonally late thunderstorms occurred in the area. This river appears to sprlng-fed, arising from a nearby plateau, and remalned at a relatively constant level, rislng somewhat after Ehe rains. A detailed descriptlon of each rLver test with permethrin is given below, for a summary of the results see Table 3. 50. 21 November 1985. A gill net was placed across the stream at 79 m in an effort to collect any shrimp that mlght be dead of moribund and drlft wlth the current. Ten minutes after the treatment, two adult terrestrlal lnsects (1 Anisoptera, moribund: 1 lightning bug, dead) were found floating on the surface. Aquatlc adult llemiptera(Pleldae, Plea sp.) were actlng disoriented. After one hour at station O m, Ephemeroptera larvae (0ligoneuriidae, OligoneurLopsis sp.) were found morlbund. Some of the Ephemeroptera had Simulildae (Simullum (Phoretomyia) bernerl) atLached to theirprosterna. After 1.5 hour at statio" O ,, we Eundla Grge EErfrop-(carapace length 38 mm) that acted normal, but was soft as lf lt had just molEed or was getting ready to molt. The 9111 net was checked each hour, only tow healthy flsh r,rere captured in lt.Thls method of capturing drifting organlsms was abandoned, since lt was obvious that neither insecticlde caused thls kind of mass knockout of shrimp, at these doses. After 24 hours, nothing out of the ordlnary r.ras seen ln the rLver. After 48 hours, one shrimp rnolt-skin (carapace length 45 mn) was found at approximately 5O m. ,. OCP/VCU/HYBIO/86 .17 Page L2 51. 28 November 1985. After 17 minutes at 5 mr2-3 spp. of Coleoptera (one a Gyrelndae sp.) were effecEed, moving slowly and drifting on the surface. Odonata nymph moribund in drift. After 27 mlnutes at 79 m, Odonat,a nymphs, Hemiptera adults and one terrestrial Hymenoptera (Formicidae) were found moribund in the drift. After 37 minutes at 300 m, a large shrlmp (>1OO mm) was seen walking at the head of a rlffle. After one hour at 25 m, a small shrimp ( 3O rnm) rras seen walklng ln slack water. After 24 and 48 hours, nothing out of the ordinary was observed. 52. 5 December 1985. After 30 minutes at o m, three familles of Coleoptera (one a Gyrinidae sp.) were effected by the treatment. After 35 minutes at 2 m, one Trichoptera larva was observed in the drift, and at 79 n Gyrlnidae adults and Ephemeroptera larvae were noribund in the drift. After one hour at 79 m, Gyrinidae adults and Ephemeroptera larvae were moribund. After one hour 37 rninutes at 300 m, and Ephemeroptera larvae (I{eptagenlldae) was moribund. At one hour 40 mlnutes at 5O m, a small shrimp was found dead. At one hour 5O minutes at 50 m, an Odonata nymph was observed morLbund. After 24 and 48 hours, nothing out of the ordlnary was observed. 53. 12 December 1985. At the beginnlng of the test, the turbidity was increased from the previous tLmes because of rain the night before ln the area. After 34 mLnutes at 7O m, a morLbund fish (Barbus (?) sp.) was found. After 44 ninutes at 50 m, a large crab was found moribund and two smaI1 fish were dead. After 54 mlnutes at 25 m, a frog(-50 mrn) was found moribund. After 59 minutes between O-79 m, there were a number of moribund or dead aquatic insects in the drift. After 24 and 48 hours, nothing out of the ordinary was observed. Discussion of permethrin River Tests 54. Norma11y, shrlmp were not observed in the untreated rivers. Durlng three of the four river test.s, shrimp were observed moving in the test section, after treatment. Only one shrimp was killed by the insectlclde. Permethrlm appeared to have lit!le deleterlous effect on shrimp ln these river tests. 55. Aquatlc (and terrestrial) insects were effected by the treatment, malnly Ephemeroptera and Coleoptera. In other studies, Ephemeroptera (nostly Baetidae) were adversely effected by permethrln (Mulla and Darwazh 1976, Mul1a et a1. 1978, 1980, Paugy et al. 1984). Muirhead-Thompson (1978) reported that Baetis rhodani, Gammarus pulex and Slmullum equl-num exhlblted a high degree of actlvatlon and detachment. from the substrate with short permethrin exposures, whLle llydropsyche pellucidula and Brachycentrus subnubllis do not. Aerial spraying (7O-rams a.i./IEfii'th permethrin resulted in an immediate increase of aquatie Lnsects (Klngsbury L976). 56. At the tirne of the last river test wlth permethrin, lt rained the night before and more sediment was suspended i.n the rlver than in the previous tests. Unfortunately, we dld not have a thermometer wlth us to measure the water temperature. The water temperature in Ehe Anle River had remained 1ow after the Harmattan, so the tenperature ln the Arnou River was probably lower than 23-24 C. With this last test, fish, a crab, and a frog were intoxlcated. These animals were not effected by the Permethrlm treatment here, previously. Pernethrin has a low toxlclty to flsh in lower doses (Kingsbury 1-976, Muirhead-Thompson 1978, Mulla et al. 1981). Aerial spraylngs(1.9-530 grams a.i./ha) for adult Simulium damnosum and Glossina specles control have producedtrrt"offish,crabanas@1.1frE-]ffikeneta1.197B,Smies et a1. 1980, Douben et al. 1985). 57. By chance the locat.ion I selected to apply the permethrin treatment ls the exact spot that OCP uses as an adult capture station on the Amou River ({126L2). Capture data from Ehe Atakpame, Togo office showed the effects of the permethrln treatment on the blEe raEe and numbers of parous females (Tab1e 5). The percentage of parous females greatly lncreased after treatment downstream from the collectlng slte, indlcatlng a decrease in the numbers of nulllparous females entering the populatlon. OCP/VCU/HYBIO/86 .17 Page 13 Carbosulfan River Test 58. The site selected for the carbosulfan river test was the Anie River, starEing approximately 185 m upstream from the road bridge. The sectlon was straight and could be waded for all exeept a deep pool area beEween 2O0-3OO m. The section nas observed mainly aE statlons 50, 1O0, 195 and 300 m. The lnsectlclde was applied in the tail of a rapid, as trro channels joined after passing around an island. The area between lOO- 195 m is a bathing and laundry area. 59. The rlver at this tlme of year, does not look that good for shrlmp because there is little overhanglng or lnundated vegetation. Electro-fishing showed low numbers of shrimp present, but speclmens of all slzes were observed in the area. This river, unlike the Amou Rlver, does not rely on groundwater, but on runoff. The river discharge continued to decrease throughout our vlslts. 60. 19 Novernber 1985. Wlthln 5 mLnutes at 50 m, Ilemiptera (Pleldae sp.) were swirnming disoriented. After 15 rninutes at 1OO mr. Ephemeroptera (Heptageniidae) Notonurus sp.) were dlsorlented. After one hour, Epherneroptera (Ileptagenildae, Orectogyrus sp.) were disoriented and dead, Gyrinidae between 1O0 to 20O* n swimming wl1d1y, many Odonara (Gonphidae 2 spp.) nymphs moribund at 1OO m and 2O0 m, at lOO n Plecoptera (Perlidae sp.) nymph moribund, Coleoptera (Ilydrophilus sp., Ilydraenidae sp.) found morlbund. Chlldren said there ldere a number a smalI flsh moribund in Ehe drlft at 195 m, and shrotly afterwards a number of cattle egrets were feeding heavily ln the shallows at 300 m. After one hour 3 mlnutes at 1OO m, a juvenile Gerridae was found noribund on the surface. After one hour 55 minutes, a smal1 dead shrimp was found at 70 m. After two hours at 300 m, locaL children had colleeted a number of small, dead Cichlldae (-2O'4O rnn), with thelr mouEh agape. A second dead shrimp was found at -7O m. After 24 hours nothing unusual was observed and locals said there have been no further problems. After 48 hours, nothing unusual was seen. 61. 26 November 1985. After 30 minutes at -60-70 m, about 5O fish, the same specLes as before are moribund or dead. After 4O minutes at 150 m, a sma11 dead fish was found. After one hour Co1-eoptera (Dytlscidae sp., Hydrophllus sp.) and Hemiptera(Pleldae sp.) were found ln a side pool, with loss of-Aoordinatlon. After one hour tlrenty mLnutes at 1OO m, a large, healthy shrlmp was observed under a rock. After one hour fourty mlnutes at 30 m, a Clchlldae (Hernlchromis fasclatus) was collected noribund. At 170 m another H. fgps,leqqq was-fyfng;;tioiGss on the bottom, bur moved away when touched. After 241oiffit-Too m, two shrimp molt skl-ns were found. After 48 hours at 7O m, a partial shrlmp molt skin was found. 62. 3 December 1985. in drift, and Gyrlnidae morlbund Odonata adult H. fasciatus were dead. 63. 10 December 1985. After 4O minutes at 70 m, Odonata (Gomphldae sp.) nymphs andIlemiptera (Nepidae sp.) moribund. At one hour 50 minutes at O m, -10-15 smal1 flsh, Odonata (Anisopter) nymph and small shrimp were dead. After 24 ar.d.48 hours, nothing unusual noted. 64. Only a few shrlmp were killed by Ehe carbosulfan treatment, and in the rlverlnetests, lt appeared that carbosulfan had a low toxlciLy to I'I. vollenhovenll. Increased drlft of aquatic lnsects was noted each tlme. Carbaryl c-ause.s an fncrease indrift of stream organisms (Courternanch and Glbbs L98O). The most lnterestlng observatlon rras the specles specLfic toxicity of Carbosulfan for Hemlchromls fasciatus.Someofthesef1sh,usua11yfinger1ingsof2o-4omm'wereki11ed@ carbosulfan treatment. After 26 minutes at -7O m, Ephemeroptera nymphs (3 mm) rnoribund novlng very fast on the surfaee. After 48 minutes at 3OO m, a Anisoptera was seen on the surface. At O m, a number of smalL After 24 artd 48 hours, nothing out of the ordlnary was seen. ,l 0cP/vcu/HYBro/86 .17 Page 14 65. At thls site there are mussel and freshwater oysters. These are collected for food, more often than the shrimp are. During the last two field tests, she11s of recently dead mussels were found. These could have been collected and cleaned by humans, died naturally, or died because of the lnsecticide treatment. RECOI'IMENDATIONS 66. In riverlne systems, I belleve it ls safe to use permethrln mlnutes and carbosulfan O.O5O rf:C/\/LO minutes. oCP/ONCIIo plans to as backup insectieldes in areas of temephos resistant populations the main rivers. at o.015 u.ClLlLo use these chemicals of Simullum spp. in 67. Treatment should be confined to the daylight hours, lf posstble. species are more active at night and it has been suggested that evenlng may be more toxlc (Takken et aL.1978). I believe OCPrs normal aerial linited to daylight hours. Macrobrachlum appllcatlons spraying is 68. Increased turbidity and lower water temperature appear to increase the toxiclty of permeLhrin to higher animal groups. Permethrln toxlciLy ls negat.ively correlated with temperature (Kumaraguru and Beamish 1981, Douben et a1. 1985). Consideratlon should be given to a lower dose or time exposure, under these conditions. 69. Carbosulfan selectively kills Hemichromls faseiatus and posslbly other fish species,main1ythejuveni1es.wt.e''@eco11ectedandeatenby humans. 70. If shrimp (and crab) are consldered by the Ecology Comrnittee to be an lmportant part of the riverine ecosystem ln the OCP project area, more ls needed to be known about thelr biology and ecology. Millerrs (1971) work is the only study that has dealt extensively with the West African shrimp species common in the Mono River drainage, and that work was done on a coastal population. 71. In the Mono Rlver drainage of Togo, mussels and freshwater oysters (Etherla elipttca) are common. These are readlly used by the local human population as a food source, more extensively than the shrimp, it appears. In treatment areas near human popul-atlons, the concentration of lnsectlcldes by these sesslle organisms (as well as flsh and shrimp) should be of concern. Studies of thls type have been done before by WHO on other lnsectlcides (Quelennec et al. L977). It has been reported that both insectlcide contaminated water and sedlment are causes of toxicity to arthropods (Nimmo et al. L971, Friesen et a1. 1982). 72. The OCP/ONCHO offtce at Ouagadougou and Bouake should each have one, or more, 5O meter or 100 meter surveyorrs tape of cloth, flber glass or metal for river surveying. Page 15 Llterature cited Ahsanullah (M.), 1976. Acute toxicity of cadmlum and zlnc to seven invertebrate specles from Western Port, VictorLa. Australian J. Mar. Freshw. Res. 272187-L96. Albaugh (D.W.), L972. Insecticide tolerance of two crayfish populatlons Procambarus acutus- in South Central Texas. Bull. Environ. Contam. Toxicol. 8(6):334-338. -Amrine Jr. (J.W.), 1983. Measuring stream discharge and calculating treatment rates of Bacillus thurengiensis (H-14) for black f1y control. Mosq. News 43(1):17-21. Anonymous 1966. Togo. Officlal standard names. Gazetteer No.98. 0ffice Geogra., Dept.Int., Washington, D. C. 100 pp. Bluzat (R.) and Seuge (J.), L979. Etude de la toxiclt6 chronique de deux insectlcides de Lymnea stagnalls L. (Mollusque: Gasteropode: Pulmone). I Croissance des coquilles.Ilydrobiol. 65( 3) 2245-255. Bounlas (M.), Dujin (N.) and Popeskovlc (D.S.), 1985. Sublethal effects of a synerhicpyrethroid, deltamethrin, on the glycemina, the llpemia, and the gut alkaline phosphatases of honeybees. Pest. Biochem. Physlol. 24(2) : 149-160. Bridge (W.R.), 1961. disappearance of endrln from fish and other materials of a pond environment. Trans. amer. flsh. Soc. 402332-334. Camougis (G.), L973. mode of action of pyrethrum on arthropod nerves. In (J.E.) Casida(ed.9. Pyrethrum. The natural insectictde. Academic press, New york. Carter (F.L.), and Graves (J.B.), L973. Measuring effects of insecticldes on aquatic animals. La. Agric. L6(2):14-15. Chai-ryarach (S.V.) Ratananun and Harrel (C.H.),1975. Acute toxicity of the lnsecEicides toxaphene and carbaryl and the herblcides propanll and molinate to four specles of aquatic organlsms. Bul1. Envlron. Contam. Toxicol. 14(3):2BL-284. Cheah (M.), Avault Jr. (J.W.) and Graves (J.B.), L979. Some effets of rice pesticides on crawfish. La. Agric. 23(2):8-9, 11. Cheah (M.), Avault Jr. (M.W.) and Graves (J.B.), 1980. Acute toxlclEy of selecred ricepesticides to crayfish Procambarus cLarkii. Prog. Fish.-Cu1t. 42(3) 2169-L72. Courtemanch (D.L.) and Gibbs (K.E.), 1980. Short and long-term effects of forest spraylng of carbaryl (Sevin-4-oil) on stream invertebrates. Can. Entomol. lL2z27l-276. Daget (J.) et Durand (J.R.), 1981. Poissons. pp. 687-77L in Durand, (J.R.) et LevQque(C) (eds). Flore et faune aquatlques de lrAfrique sahelo-soudanienne. tome II. ORSTOM,Parls, IDT No. 45. Demoulin (G.), 1981. Ephemeroptdres. pp. 4O7-443 in Durand, (J.R.)(eds.). flore et faune aquatiques de ltAfrique sahelo-soudanienne. Parls IDT No. 45. Dethier (M.), 1981. HeteroprEres. pp. 661-685 in Durand, (J.R.) et(eds.). Flore et faune aquatiques de lrAfrlque sahelo-soudanienne.Paris. IDT No.45. et Lev6que (C.) Tome II. ORSTOM, Lev6que (C.) tome II. ORSTOM Douben (P.E.T.), Everts (J.W.) and Koeman (J.H.), 1985, Side effects of pyrerrholds used to control adults of simullum damnosum s.1. ln a riverlne forest in Togo (westAfrica).DeptToxico1.,eg@Wagen1ngen,theNether1ands Page 16 Everts (J.W.), Boon von Ochssee (G.A.), Pak (G.A.) and Koeman (J.II.), L978. Reporr on the side effects of experimental insecticide spraylng by helicopter against Glossina spp. in Upper Volta, 1978. Dept. toxicol, Agrlcultural- Univ., Wageningen, the Netherlands.i+25pp. Forge (P.), 1981. col6optEres. pp. 487-5L6 in Durand (J.R.) et Levdque (C.) (eds). FLore et faune aquatiques de lrAfrique sahelo-soudanlenne. Tome II. ORSTOM, Parls. IDT No. 45 Fowler (S.W.), M. Heyraud and Beasley (T.M.), L975. ExperLmental studles on plutonium kinetics ln marine biota. pp. 157-177 7n impacts of of nuclear releases lnto the aquatie environment. Vienna, IAEA. Frisen, Margaret (K.), Galloway (T.D.) and Flannagan (J.F.), 1983. toxicity of the insecticide permethrin ln water and sedirnent to nyrnphs of the burrowing rnayfly Hexagenia rlplda (ephemeropteras ephemerldae). can. Entomol.115:1O07-1014. Gruvel (A.)r 1908. Les p6cheries des c6tes du s6n6ga1 et des rividres du sud. Soci6t6 Edit. Geographique maritime et coloniale, Parls. 245 pp. Gruvel (A.), L9L2. Les crustac6s comestibles de la c6te occidentale drAfrlque. mission Gruvel sur la c6te occidentale drAfrique (1909-1910). Ann. Inst. Ocenaogr. Monaco 5(1):1-18. Guary (J.C.) and Fowler (S.W.), 1978. Uptake frorn water and tlssue dlsEribution of neptunium-Z37 in crabs, shrimp and mussels. Mar. po11ut. bu11. 9:331-334. Buary (J.C.), Masson (M.) and Fralzier (A.), L976. Etude preliminaire, in situ, de 1a distrlbution du plutonlum dans dlff6rents tissus et organes de Cancer pagurus(Crustacea: decapoda) et de pleuronectes platessa (Plsces: pleuronecLldae). Mar. bLo1. 36rL3-17 . Harper (P.P.) and Stewart (K.W.),1984. plecoptera. pp. L82-230 tn Merritt (R.W.) and Cumulns (K.W. (eds.). an introductlon to the aquatic insects of north Ameri.ca. 2nd ed. Kendall/Hunt Pub1. Co., Dubuque, Iowa. xili * 722 pp. Hart (R:C.) 1980. Enbryonie duration and post embryonic growth rates of the tropical freshwater shrlmp Carldi.na nilotlca (Decapoda: Atyidae) under laboratory and experimental flel-d condltions. Freshwat. biol. LOz297-3L5. Holthuls (L.B.), 1949. on some specles of macrobrachlum (Crustacea: Decapoda) from west Africa. EOS XXV: 175-185 Holthuis (L.B.) 1980. vol l-shrimp and prawns of the world. FAO species catalogue. FAOfisherles synopsls No. 125, Vol. 1. FIR/S125 Vol 1. FAO, Rome. 271 pp. Horne (F.) and Beisser (S.), 1977. Dlstrlbutlon of river shrtmp ln the Guadalupe and San Marcos Rivers of central Texas, U.S.A. (Decapoda, Caridea). Crustaceana 33:56-60. Jolly (Jr. A.L.) Avault (J.W.), Koance (Jr. K. L.) and Graves (J.B.), L978a. Acute toxiclty of permethrin to several aquatlc animals Trans. Amer. Fish. Soc. 107-825-827. Jolly (A.L.), Graves (J.B.), Avault (J.I{.) and Koance (K.L.), 1978. Effects of a new insectlclde on aquatlc animals. La. agr. 2L(2):3, 16 Kingsbury (P.D.), L976. effects of an aerlal applicatlon of the synthetlc pyrethrold permet.rhin on a forest stream. manlt. entomol. 10:9-L7. Kumaraguru (A.K.) and Beamlsh (f.W.H.), 1981. Lethal toxlclty of Permethrln (NRDC-143) to rainbow trout, Salmo galrdneri in relation to body wetght and water temperature. Wat. Res. 15:5=3-505. Lee (C.L.) and Macrobrachium Flelder (D.R.), L979. australiense Holthuis, Page 17 A mass migratlon of the freswater prardn, 1950 (Decapoda, Palaemonldae). Crustaceana 37 :2L9- 222. Lewis, food of Lowe (J.I.)r L97O. Bioassay screening test-carbofuran. p. 101 ln initial sclentific and minleconomlc review of carbofuran. U.S. Environ Prot. Agency. npes+O/f-76-009. Maciolek (J.A.), L972. Macrobaqtrium 1ar as a culture prawn ln the tropical insularpacific. proc. Ann. conFffiffi-Ts5o-f. state Game Fish Comrnissloners. 52:55o-558. Marsden, Paul (J.), Eichi Kuwano and Roy Fukuto (T.), l.982. Metabollsm of carbosulfan2r3-Dihydro-2r2'd,imethylbenzofutan-7-yl (di-n-butylaminothio) methylcarbamare in rhe rat and house fly. Pest. Blochem. Physiol. 18:38-48. Miller, Georges (C.), L97L. Commercial fishery and biology of the fresh-water shrimp, Macrobrachium, ln the lower St. Paul Rlver, Llberia, L952-53. Nat. Mar. Fish. serv.Trop. Atlantic Biological Lab., Miami, FL. 33149. spec. Scl. Rep.-Fish. 626. L3 pp. Miller (T.A.), L976. Distinguishlng between carbamate and organophosphate insecticidepoisoning in house flles by symptornology. Pest. Blochem. Physiol. 6:3O7-319. Ml1ler (T.A.) and Kennedy (J.M.), L972. flight monitor activity of house flies as effected by temperature and insecticides. Pest. Biochem. Physlol. 2:206. Miller (T.A.) and Kennedy (J.M.), L973. Ln vlvo measurement of house f1y temperature,flight muscle potentlals, heartbeat and locof,nGlon during tnsecticide poisonLng. pest.Physlol. 3:37. Monod (T.), L966. Crevettes et crabes de la c6te occl-dentale drAfrique. pp. 103-234 tn R6union de speclallstes C.S.A. sur les Crustac6s, Zanzibar 1964, Ilem. I.F.A.N., No. 77. Monod (T.), 1980. Decapodes. pp 369-389 in Durand (J.R.) et Lev6que (C.) (eds). Flore et faune aquatlques de lrAfrique sahelo-soudanlenne. Tome I, ORSTOM, parls. IDT No. 44. Muir (D.c.G.), Merner (D.A.), Blouw (A.p.), Grift (N.p.) and Lockharr (w.L.), lg7g.Effect of water chemistry on the uptake of organlc pollutants by fish ln river water.pp. L2'26 ln Kl-averkamp (J.F.), Leonhard (S.L.) and Marshall (K.E.) (eds.). proc. 6rhA. Aquat. Toxicity Workshop, Winnepeg, Manitoba, 1979. Can Tech. Rep. Fish. Aq. Sct.975. John (B.), Jonet Ward and Alaln Mclver, 1966. the freshwater shrimp MacrobrachLum earclnus the breeding cyc1e, growth and(Llnnaeus). crustaceana LOz48-52. pyrethroids Roy. Soc. Muirhead-Thompson (R.C.), l-97O. the potentiatlng effect of pyrethrins and on the action of organophosphorus larvicldes ln Simullum control. Trans.Trop. Med. IIyg. 64(4):895-906. Muirhead-Thompson (R.C.), 1978. Lethal and behavorlal lmpacr of permethrtn (NRDC 143) on selected stream macrolnvertebrates. Mosq. News 3g(2) :1g5-19o. Mulla (M.S.) and Hussan (A.) Darwazeh (H.A.) L976. Field evaluatlon of new mosquitolarvicldes and their lmpacL on some non target organlsms. Mosq. news 36(3) z25L-256. Mulla (M.S.), Datwazeh (II.A.) and Dhl1lon (M.S.), 1980. New pyrethroids as mosquitolarvlcldes and their effects on non target organLsms. Mosq. news 40(1):6-L2. Mulla (M.S.), Darwazeh (H.A.) and Dhillon (M.S.), decamethrin and permethrtn and freshwater flshesToxicol. 262689-695. 1981. irnpact and joint acrion of on mosqulto€s. Bul1. Environ. Contam. aPage 18 Mu1la (M.S.), Navvab-Gojrati (II.A.) and Darwazeh I{.A:), L978. Blological activlty andlongevlty of new synthetic pyrethroids against mosquitoes and some non t.arget insects. Mosq. News 38(1):9-96. Narahashi (T.)r 1980. Site and types of actlon of pyrethroids on nerve menbrane. pp. 15-17 ln Pyrethroid lnsectlcides : chemistry and actlon. Tables Rondes Roussel UCLAI. No.37 Naqvi (s.M.) and Ferguson (D.E.), 1970. Levels of lnsecticide resistance in fresh-warer shrlmp, Palaemonetes kadlakensis. Trans. Amer. Flsh. soc. 992696-699. Nimmo (D.R. ), wilson (P.D. ), Blackman (R.R. ) and wilson (A.J. ) lr. l.g7]-.Polychlorinated btphenyl absorbed frorn sediments by fiddler crabs and pink shrimp. nature 231:50-52. Omkar and Ram Murti, 1985. Toxicity of some pestlcides to the freshwater prawn, Macrobrachium dayanum (Henderson) (Decapoda, Caridea). Crustaceana 49 (1):1-6. omkar and Shukla (G.S.). 1985. Toxicity of lnsectlcides to Macrobrachium lamarrel(H. Milne Edwards) (Decapoda, palaemonidae). crusraceana 4gflt : 1T. Ohno (A.),Ogasawara (Y.) and Yasuda (F.), L977. Distributlon and habitat of the long- armed freshwater prawns of the genus Macrobrachium Ln the Shimanto Rlver, Shikoku.Nihon Seitaigakkai 27 :23-32 Paugy (D.), Yam6ogo (L.), Bihoum (M.) and Coulibaly (B.), L984. Short rerm impacr ofPermethrl,n on the non-target aquatie fauna. OCP/VCU/HYBIO/84.14. WHO, Ouagadougou, Burklna Faso. 14 pp. Phillppon (B.). Simullidae. pp 643-659 in Durand (J.R.) et Levdque (C.) (eds.). Flore et faune aquatiques de lrAfrlque sah6lo-Eudanlenne. Tome II. ORSTOM, parts. IDT No.45 . Quelennec (G.), Miles (J.w.), Dejoux (c.) and de Merona (B.), 1977. cheraical monitoring for temephos in mud, oysters and flsh from a rlver wlthin the OnchocerciasisControl Programme ln the Volta River basin area. WHO/VBC/1977.683. WHo, Geneva. 6 pp. Salgado Vlncent (L.)' Stephen (N.) Irvlng and Miller (T.A.). 1983, The inportance of nerve terminal depolarlzation ln pyrethroid polsoning of insects. Pest. Biochem.Physiol. 20zL69-L82. Sanders (H.O.), 1969. Toxiclty of pestlcides to crustacean Gammarus lacustrls. Tech.Papers, Bur. Sport Flsh. Wildl. 25:1-18 Sharom (M.S.) and Solomon (K.R.)r 1981. Adsorptlon and desorptlon of permethrin and other pestlcides on glass and plastic materials used ln bloassey procedures. Can. J.Fish Aq. Sci. 38:L99-2O4. Shukla (G.S.) and omkar, 1984. Insecticlde toxlcity to Macrobrachlum lamarrel (H.Milne Edwards) (Decapoda, Palaemontdae). crusraceana 46(3[lEi3EN: Smles (M.), Evers (R.II.J.), Peijnenburg (r.H.M.) and Koeman (J.H.), 1980. Environmental aspects of field trials wlth pyrethroids to eradlcate tsetsefly inNigerla. Ecotoxlcology and Environ. Safety 4zLL4-IZB. Sollaud (8.), L923. Le d6veloppement larvalre des Palaemoninae. BulL. Biol. Fr.Belglque LVII(4) :509-663. Page 19 Takken (w.), Balk (F.), Jansen (R.c.) and Koeman (J.H.), 1978. The experimental appllcation of insectlcides from a hellcopter for Ehe control of rlverine populations of Glossina tachinoi-des Ln I,Iest Afrlca. VI, Observatlons on slde-effects. PANSza(T)iFie6;- Truesdale (F.M.) and Mermllliod (W.J.), L979. The river shrimp, Macrobrachium ohione(Smith) (Decapoda, Palaemonidae) : lts abundance, reproductlon ana@E-E-e Atchafalaya River basln of Louisiana, u.s.A. crustraceana 36t6L-73. Willlanson (D.I.), 972. LarvaL development in a marine and a freshwater specles of Palaemonldae). Crustaceana 23:282-298.I'I4qlgbtach ium ( Decapoda : ocr/vculrrrrc/e6.t1 h q L .x ;l. ;,=r:TlI[;.* rj,i-i., i .$liiffi *ilffiI Hilti.Nfl ==:i,:i :d:.H,l- ft:-:::.trr--'--rr. l- I =,ii.fi--te l,J-lEllfi-=I-'u [;1ll =Eir,.XEI"t lj,]Ui== ljfl ',;1,, i$ -.llr=l_l =H#e*:1*ll ::::l-.:,t :::.lt'll .-.,.t '.. ..,-1..f. ....{...1 ::::l:::: :-:l=; ....1.... ::: I : ::: !:"r.,*t,rt, 12-188 Msde rn USA J G\r o of,.tcrr lo tho C.eotlrnctcr t2-1 88 Mldc h USA ocP/vcv/rr".T0/86.L7 +\\-l.-l{i#iliJ+r* ::: : l. : \ - : :.1:'li.: I :: ::i::: : : I. I :l -: l:li: : lh + l9 l- lta $ ,,,,rctt lo tho Ccnrlmctcr 6o66 NA €m-€ Aon-m Ctl €<!lFr m-nrOa <ogNru F ruru aodrv dN aoa on-< N cfP/vctfirYT.To/a6.t7 nr on-ON- F€ otsdEo # rE rE $H * oo tsQ< r f,!{5 fE6m-h R' {a rt L4 n -d n tl'CA nn OCdi C LE Il & n ,i #il It oEf,63 ff,€ =FE 6t il il . !,t!l .5rJru (\, 6 rutlr- d+-tu5 6 6 -55Ffi 26=dqFNrn-!) oturn!a -o- -om Q6<tutu <dN --- s B o J r0 Rta OY4 !Eo ou > o{ I Jd nda OF oor €t €l)n )d{u nu dL-Lo5 0G6n6n ld lc, nndd BC Lt. e4 nn oo -o CG LLECII!(&aEEI $ma8 -G. -F. -F. ,AA-n,-rEE EE IE ?nonQ{on -L.<t<Lo- o5 0b o6n 0n on 6 Jd ld fc, d O n r.ef,[ aeeoEOEE dddd CCCC -{-a9g aatil3388 L!LLaSaoggErg \\ x FF\Na-= nnrddGro GG !LCE llLA&&gB I F P 6 a C J Eab! L loaaIt ooL CI. od2 I F a - 6c) !)o LI -E-ti4& OL -?-86laonats6- IIo oa 26qtfI ..?L O n^O - (Ue r 8.-E! CA 590 E HE 'oxaL Ugd E la3T oF 0 td .8fi{C lz! '!A ocP/\tcv/tt1To/86.L7 Table ?. Shrinp nortality courrtirrg and nc,t ctrurrtirrg rissing shrino. (lllc,ribund shrinp considered as dead. llissrng rnciudes shrino that rere eater, and shrimo that ;unped out of the tank). Date Insectieide Dose Exoosure Test krtality: {rinutes) Percent Percent Tine rith rrthout (mirr) llissing liissing &,ntrol orial ity: Percent Pert-eni Tine n:th xithout {r:rr) Ili ssing I''li ssinq ?llXIl83 Pernethrin 0,815 por 30 100 i00 l0h35o 35 0 ?lltllBS Pernethrin gl(lllgi Pernethrin 4/XII/85 Perrethrrn 0.015 ppn 1A i00 180 l0h?5e 16 $9m 7h 2?hPl n .r'lh33n 47hlln 5$40n th3l r ??h46n 3l h4r 5$38m 10h35m i0h?5n 3h3m 3lh33B 47hlln 55h40rn 95h?8m 3hSrn 30hc'5m 48h50r 3h 15't 7h20m ??h??n 55h50ru 54hSEn 100 t00 r00 t00100 r80toe t00100 100 toa 100 7A 55 75 7888 75g5 80 0.015 poa 5 0.015 ppr I 78 96 % 48 100 t0Q l3 l7 EA ..t) 65 70 00 77 377 l0/XII/85 Permethrin 0.015 ppn I ?7llll8il Carbosulfan 0,050 pp t0 ?7llll$i Carbcrsulfan 0.050 por 5 4l[ll/83 Carbosulfarr 0.050 ppm I I0/III/85 Carhosulfarr 0.0S0 ppr I Penrrethrin (lin-max) Carbosulfan (rintax) l5 70 lh 87 3h5m 87 48hl[tr 48 th 100 $r?0. 100 7h?0n 13 th L7 7h44m 13 55h50n 60 thZr 55 54h55m 44 'l 9 r00 5e 4 4 3t 85-100 8g-100 53-t00 l3-100 t5 0-37 4-37 {le0) 0-7 0-9 {53) 27 ocP/Tcu/EYBra/86.L7 6'!JOE +t)nE(l d.o,<0rrI,(JrurlJuto 'f 0r.- s 'r (:a ct 6L/!0,6LrrL(uo.or# o G ,E#oLr + a(] or E E 8t E E E E e g.E l!(r(LrEO,or L+ ,E# O, (:+ o.$ o ,o o ecti(ll.aorEr.{Eg8,5,f;1 T OJl!+o,l-,t06 rULciE0+ o L.H + o# u.-3ETE'; €r 8€ = Ct r-l a g1 tJ1 TI6r (J o ll. trJ l,lmEIL0, .-o Gf(tql oJ6A 'r, ID t/l 'Do,lr'l rtsi x >. lJ') _\+CO .r -o F< f.C]x .HL\ 'o r{1JEF.{ lr-,(D h E ,E rl^ lr-IdJ rali\J E {,ta m fq ti ,3 E IIJ =tn .E {t,ra .t_ -f{tJ (J tlt.E orF- '. (U .oF. -f .a \-{ s ru F-(9 r.2 rtj r-. ur E u lfa a) olEI ,. ,!E C) rn a (1l IU :E sl!,LLaLJ L 0r (uE .i rLJ(J (ll [,E. l; ll,LL a .J '!-c, l^. L,E o,= 'cl$(l,TLo/r,LutLTTdg L) l.) r1J tt T F co f,tu o, aa <f !u lr_i LN -s + (r) <r Lo /o t LA ..r(n .a + lr-t Lq, E a (O .'t m\' + .+ !: L0, ro3 tn m -+ + a EO E aL ulN OJ (lrG ao a!(E (r) aS.E, G, E(9 (9 ul aS.(9 (9 v2 aEt (9 t e (!9 clls ooro tn C) .a lr, ch(5, (3 E tnt4 t-tt6) r:D(5, t\J o,I F !l crt 6J u')d) !: o l:]i-- t,) .6(1'\ l)xClt0 J tt)U !=rI ,O c L -r-' o,, L at)JL u"!{: q) l.< o iiltut-- t-(lj le 1 s(r 1.' or ,'1 0, ry'Et-o ocP/vcv/H\BT)/86.L7 { Lfl,o roES+ di rnoQd(lJ .HLEUlr')LJM *888 6t.(U ,o+Lcl-Or() +3.ruoqr+Uft(ft6o(lJ(UtuHi o dO (L'o .{(JU6T l!Lro l!L+oo+ L,l(] otu U, .H (J '<ttn .](Ua(-J :T CL 6L(U +fr{(uO,LLltJor&d(ULn,#Dai +OI+CIC\t]m .:EE88ftg AE(,(lJ.<urr#,fl8Eage EI tu 4Ju tll i.- LU E*n5 '-oct6gr (rJ6J (J e .l,F L(l, E r:} 61a (9 r1J :] fr n E u r)a(J qlgt L ,uEuUI q ILl(Ul+l-E i4l+ t;trL L)(J L(y +,llJE + OrLLa(J ro o r! ,! IL oE13+ q,3 -o +(l,ELoaLUtLr!a* tl r?, lr', tn tn E a E F E rE u CL o- CE ILIUlarIrOlr lsI o..t l.slLhl+l+lars! Itcot.lLll-< I I I IILl0JtnlrE1.:t I tel-I t-)l(hl.+l+ I lf! Ilua!-+ I I I I I I I It.-IE I1.9I 1.1l.ol-+l*lalti Ilc9lr\l* I IILltul+l,!l!.t.-l.llrlt<ll.ott-+lttt+tlrt.<tlEttttt[3 IlHlttltltl*ltultldlrortlHllutlEtl-ltstl5ll()ll.fl (rJ(rJ € r3 t\ (,1 (9 lr') at, (9 fi(9 (l} t a 49 clrE oor ,! rnI I I I I I I I I I I I I I I II I I I I t I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 6. .+ -c 'tS,OJ!-) &etr) g)(9 .t o,c u1 u:t tr)d:t 11 t:J u(Dl- al 'r -(: rrfror\JJcI € @q- a rn EL 't(l tr)E(D lx qll-- L o, ft u, 'IE + o, 0 €s .!ro l- (f -t at! ocP/vcv/trt?,ro,1/86.t7 Tabie li. The effesc'bs t'tf Pti'rnrebhrirr Lr'e;rtrnerr'b at'bhe OCp captLtre stat r,::,rr ff,86 1e i,n t1ro 611nr,Lr River. at Arn,:tt-flb1c,. 'l-r;rgC,. Data 'p,^r;rlfl the O[YIS/'0NCHO c'ff icer Atal<panre, Tc'gc'. Nr..trrtberr' c,f Per*c errtFJ F.,I' rrr E, L Ir r i rr Tl- eirt rngrrrl: Dat e ,:, l" Cei p'i: t-trc;r Dat a Hlrrrr;,irr BitCrs c'f PElrC,Lt:; Ferrra I es !:1/XIiS5 { rzt. Lll 5 nFnr./ 1O rrri rr) ABi X I 1'85 ( [r. Orel6 pprn/ I tit rn i rr ) 5ixiii85(A.tlOG ppnr/1O rnirr) i?.ix i ii s5 (urr. ulr7t6 pprn./18 rn:i rr) ra.ixlit35 zBi'i I /65 4 /Xl I /45 1.?/X i :t /95 ?: 43.5 84. tt aa.9 7s.9 ].3 4e t? 3o