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'" exception of fungus. Greatest incidence of parasitism was in the Yampa River with 41. 5 per cent of all fish examined. Next high was Echo Park with 31.3 per cent and third was M::lnument Headquarters (Split M:>unta1n) with 22.2 per cent infestation. l)8mage to the fisb was difficult to estimate. The very poor condition ~ . the cham1el. catfish could certainly be due in part to the paras ites. Deformity of t~ fins could be traced in many instances to ~eat numbers ~ tbeparasites on the fin base. One small squawtish showed possible bl1ndr1ess in one eye due to the presence of three copepod parasites near it. All fish vith the copepods shOl-1ed white ulcerous growth near the po1ut of attacbmen.t. These copepods can and ho.ve caused serious problems with trout shouli this habitat ever become that type of stream. Effectiveness 2!. sampling gear rt hae been clearly demonstrated that the most effective sampl1n8 proee4ure for the Green and Yampa Rivers 1s to assemble rather sizeable working crews that are tully equipped l1ith electrofishing devices I large and sma.ll seines (Figure 5) and fish toxins for small side channels. Altboush daily sampling efforts were made by ltr. Banks, with a variety ~ gear that can normally be handled by one man" the massive physical problems and fluctuations of the Green River made sam,pling difficult and unrewarding at times. As previously mentioned, gUl nets could not be used ettectively Wltil the end of the summer. Hoop nets and tyke nets were also of little value. Throw lines caught fish, and in 'ltJS,'tty instances the only large fish. It is of great interest to note that these lines took fish only next to the shore. Beyond the third hook, about ten to fifteen feet, no fish ",ere ever taken. Certa1nl;y this suggests that most tishdid not venture far into the swUt and turbulent waters. lor one man efforts, Mr'. Eanks found a small push net quite effective in talting small fish. For many collect ions he enlisted the aid of park Service personnel or visitors in his sampling areas. For the bottom samples and plankton samples needed, an ordinary Surber square foot bottom sampler and standard plankton net were adequate. October ~ r.esults On October 12, Dr. Hagen traveled to Dinosaur National M:>nument to Eke necessary arrangements with Park Service personnel for an extensive s~l1ng expedition to cover the same stations investigated in october ot 1961. Mr. Eanks and Dr. Hagen visited several of the sites on the Green and Yampa Rivers and made several preliminary observations and checks on the following two days. Dr. Hagen returned to the M:>nument uith 14 students on October 19. The Dlen were divid"'d into two survey parties. .Crc~r No. 'l thoroughly . =7= -