rAll.C1.1W_Ea FISHERIES RESEARCH' BOARD OF CANADA Translation Series No. 717 , Sa1m0 si3lar Lin., its parasiticfauna and ita nutrition in the sea and in fresh waters.': A:parasitological-biological atudy ; • By Friedrich,.AugustHeitz': Original title: Salmo salar Lin., seine Parasitenfauna und seine ErnNhrung im Meer und im Süsswasser. Einè parasitologisch-biôlogische Studie. Inaugural-Dissertation to attain a Doctorts Degree • at the Philosophical Faculty of the University of Basle. Stuttgart.' 139 pp. 1917. Translated .by Translation Bureau (MV) .Foreign Languagés Division : . ' . ••. -Department.of the Secretary of Stat e.of Canada , . Fisheries Research Board of Canada Biological Station, St. Andrews, N. • „i f. SALMO SALAR LIN., its parasitic fauna and its nutrition in the sea and in fresh waters , • Inaugural Dissertation to attain a Doctor's Degree • at the Philosophical Faculty of the 'University of Basle, Stuttgart 1917 E. Schweizerbartische Verlagsbuchhandlung . • NUgele & Dr.,Sproesser. t. ove•d parents Approved by the Department of Mathematics and Natural Sciences of the Philosophical Faculty upon application by Professor Dr. Fr. ZSCHOKKE and Professor Dr. P. STEINMANN Professor Dr. Fr. FICHTER • Dean January 26, 1916 n Contents I. Introduction 4 (1) * 1. Preface 4 (1) 2. The nutrition of Salmo salar at various developmental stages, and in the sea and in fresh waters 9(4) 3 • Chronological review of authors who have examined Salmo salar for parasites or at'least have mentioned and described parasites from salmon 26 (15) 4. History of the research into the parasitic fauna of salmon 33 (21) II. Systematic part • 42 (28) I. Preliminary remarks, 42 (28) 2. Endoparasites 45 (29) (a)Trematodes S 45 ( 29) (b) Cestodes S 58 (39) (c)Nematodes S 81 (55) (d)Acanthocephala 92 (62) (e) Parasites froM American and Asiatic salmon 117 (78) 3. Ectoparasites S S 121 (81) (a) Hirudinea 122 (82) .(b) Copepodfs 123 (82) III. Comparative faunistic part 126 (85) 1. Rhine salmon and its parasitic fauna 126 (85) • 2. The parasitic fauna of other 'salmon and salmon species 148 (100) 3. The parasitic fauna of some other migratory fish S 169 (114) IV. Geographical part 178 (121) V. Summary of results • 189 (128) VI. Bibliography and explanation of figures 195 (133) Translator's note: the figures,in-brackets -refer-to-the pages in the original-text -- 3 1. Introduction 1. Preface On the basis of his intensive studies, Friedrich MIESCHER (66) makes the following statement: "From the time it leaves the sea until it hAs spawned, t Rhine salmon doés not eat,'and usually not even afterwards." Friedrich ZSCHOKKE (110, 111, 112, 114) tried to furnish parasitological proof for MIESCHER's statement by inferring from the qualitative and quantitative composition of the parasitic fauna of Salmo salar in various waters the nutritional habits of the fish in the sea and in the various rivers. He reached the foilowing conclusion: "Salmon does not take in any food in fresh waters, at least not while ascending and spawning." Since the publication of these two reports, many more have been published by English, Scottish and Dutch researchers, in Particular, which in part reject, in part agree with the above •views formulated on the basis of accurate and thorough studies. •Until today opinions differ on the feeding or fasting of salmbn fresliwaterS., • It appeared therefore desirable to continue ZSCHOKKEts studies on'a large scale to achieve definite results. Another reason for this study was also the fact that the abundance of salmon in the Rhine is decreasing slowly on account of increasingly Smaller spawning grounds. By dams of all sorts of factories, but particularly by the many power stations, the spawning grounds of the salmon which used to ascend the Aare, Reu8 and Limmat Rivers as far as the Alps, have been restricted pb the short distance between Augst and Basle in the Upper Rhine. For this reason and the-one nfeiftioned previously I started __— studies on the salmon, and put myself a question which I tried to answer'first for the Rhine salmon, and then also for salmon from other waters, namely the questiOn: Can inferences as to the nutritional habits of Salmo salar be drawn from the parasitic fauna of the Rhine salmon and from the parasitic faunas of salmon of other waters, and by comparing these faunas with each other? , to express it in more general terms: What is the significance of parasitological-faunistic );• findings for nut-riefen biological reflectionsl on. n - iri? I started my studies at the end of the'summer term of 1912. The conditions prevailing here permitted my collecting efficient •fish material only during the autumn and winter months. Only a few intestines were examined during the spring and summer months and those were mainly of non-Swiss salmon. A total of 200 salmon' intestines was examined which were of the following origins: From the Upper Rhine ' i28 , River area o From the Middle Rhine 8 the Rhine From the Lower Rhine (including the 11 170 mouth of the Rhine) 17 From the Moselle River (Alzet) 17_ From the Weser—RilieF-- 21) From the Loire River 5 From Norway 200 Professor Dr. Fr. ZSCHOKKE was good enough to put at my disposal the material collected by him) fOr statistical purposes and I shall make use of it particularly in the chapters on the frequency, number and origin of,the salmon parasites. Here 1 would also like to include the following material in order to give à complete review of all the parasitàs collected el. Basle: 1889: • 45 salmon fich from the 1891: 129 ' 11 1896: 5 from the Middle and Upper Rhine 1896: 3 from the Dutch Rhine 10 from the North Sea Total: 181 salmon fish I have not included the 20 salmon specimens examined by HAUSMANN (3.5) in 1897 because his parasitological examination dealt only with trematodes. • If we add the salmon examined by ZSCHOKKE and by -myself for parasites, We get a total of 381 salmon,.307 of which came from the Rhine and 74 of which originated from other waters, partly from rivers, partly from the sea., The material to be examined - the fish intestines - were put at my disposal most willingly by fishmongers in Basle. Whenever possible, the intestine was cut off at the anus and pulled out with the head, together with all connected organs such as liver, spleen,agdnital glands,etc. In this manner I at least obtained the complete intestines and presumably also the Majority of parasites in the body cavity. It was of course impossible to ascertain "what remained behind in the body cavity, but in my opinion itwas not much. Most of the parasites were incapsulated in or on the various glands, on the intestine and between the pyloric appendages. Now and then I obtained intestines alsb from inns. Several times I took blood frôm a fresh catch of Rhine salmon on the spot to examine it for blood parasites, but the results of such tests were always negative. I would like to take this opportunity to express my heart- felt gratitude to everyone who has assisted this study by his advice or cooperation. Above all I wish to thank my venerated teacher, Professor Dr. Fr. ZSCHOKKE, from the bottom of my heart for his unfailing devotion in supervising my work, encouraging and assisting me with valuable advice and permitting me to make full use at any time of his extensive collection of literature of parasites. Thanks to him I wes able to use the facilities of the Zoological Station at any time, even during the war which caused considerable delay in my work, and also during the long vacations, I was thereby enabled to continue my work in spite of having to devote much time to my duties in the border control service 1914/15. I derived the greatest possible benefit from his extensivè experiences in the field of parasitology, especially during our ■ •■ working together on the parasites of Salmonidae from Kamchatka. I am greatly indebted to Dr. C. von JAMICKI for his vivid ready interest in the progress of my studies and his/advice and cooperation. I would also like to thank the two fishmongers in Basle, .2 Mr. CHRISTEN and Mr. GLASER; especially Mr. Christen andhhis fi supplied me in the most generous way with an abundance : of mater for 'my studies and always tried to comply with all.my .requests 2: The nutrition of Salmo salar at various develoe- mental stages, in the sea and in fresh waters In the following I would like to summarize our knowledge on the nutritional habits and food of the salmon at its various developmental stages and in its various habitats (sea and rivers). We will see that opinions still differ widely on all questions concerning the nutrition of Salmo salar. (a) The young fish in fresh waters: Depending on the temperature of the water and on general climatic conditions, the young salmon hatch from.the egg membrane after 45 - 148 days..They are born as tiny fish, with the vitelline sac still attached to them which is their first source of food. Their mobility increases by the gradual resorption of the vitellus,until finally they are able to look for food themselves. They find the rich mud and àoil fauna of a mountain stream ready for them to feed on. The bigger the fish becomes, the more insatiable is its aPpetite. It does not ' feed so much on the plancton which occurs only in scarce amounts in flowing water, but mainly on the living beings under stones and on' plants. The following list will give an. idea of the variety of food of the young salmon: According to HOEK (40, 41): Larvae of Chironomus, Baeti Simulium, Perla, Sydropsyche, Cloe, Enhemerella; diptera, insects; rarely Ancylus (house with snail); insect eggs.