105 



between Tsetse-flies and big game, cannot fail to have noticed in certain 

 instances a marked conflict of evidence and opinion among some of 

 those best qualified to furnish both. This fact alone should make 

 us hesitate before adopting what to some may appear obvious con- 

 clusions. A further word of warning also seems necessary. The close 

 association admittedly existing between certain species of Tsetse-fly 

 and big game, in parts of the African continent, must on no account 

 be assumed to be those obtaining between game and all species of 

 Glossina, everywhere throughout their range. Thus, writing with 

 regard to conditions in the islands in Lake Victoria, Uganda, between 

 Entebbe and Jinja, Carpenter (26) considers that the extermination 

 of large mammals would have no effect upon G. palpalis, which prefers 

 reptilian blood (see above, p. 91), and that the destruction of all 

 crocodiles and other large reptiles would be a difficult matter. 



We may conclude from what has been stated above that, though 

 there be definite grounds for considering big game as constituting a 

 reserve of food enabling Tsetse-flies such as G. morsitans, G. pallidipes 

 and G. brevipalpis to subsist in a given region, there is as yet no scientific 

 proof that the presence of these animals is absolutely indispensable to 

 the continued existence of the insects. Under these conditions the 

 utmost caution would seem to be necessary before definitely advising 

 the taking of measures which would have irreparable results. 



" The disappearance of species of animals which adorn our globe, 

 and are important assets in the maintenance of native populations," 

 says M. Perrier, " besides being regrettable in the highest degree from 

 a scientific standpoint, would have repercussions that it is impossible 

 to foresee. By destroying the equilibrium established in nature, we 

 may lay ourselves open to disasters of the most serious description." 



Before we decide to take action in the sense indicated, science must 

 have expressed its opinion with no uncertain voice, and even though 

 it should definitely pronounce judgment against big game, we must 

 see that the measures that we are compelled to take do not degenerate 

 into abuse, and are limited to zones in which the introduction of stock- 

 raising is not merely possible but also realisable under present condi- 

 tions. To permit the destruction of important natural resources, on 

 the pretext that they may be inimical to more or less uncertain 

 colonising projects, would be tantamount to sacrificing substance for 

 shadow. A further preliminary condition is that we shall have devoted 

 serious study to the other possible methods of destroying or banishing 

 Tsetse-flies, and that no effective treatment for trypanosomiases has 

 been discovered. 1 



1 In this connection the following extract from a paper by the late Captain 

 R. B. Woosnam (164) is worth quoting : 



" From the point of view of game preservation there are six questions which 

 need answers, and until these questions are answered it is impossible to decide 

 upon a definite and practically useful plan of campaign. Briefly these six 

 questions are : 



"1. Are game animals the only wild animals which are acting" as ' reservoirs ' 



for trypanosomes ? 



" 2. Are the trypanosomes found in the blood of game animals pathogenic 

 for man and domestic animals ? And if so, are not the trypanosomes 

 found in the blood of other animals also pathogenic ? 

 "3. Are tsetse flies the only transmitting agents of these trypanosomes in the 



infected areas ? 



"4. Are game animals the only source from which the tsetse flies or other 

 transmitting agents draw their blood supply ? And if not, what are 

 the other sources of supply ? 

 "5. Can tsetse flies live and breed upon food other than blood, such as plant 



juices ? 



" 6. Are the distribution, increase and spread of tsetse flies, if this latter 

 occurs, dependent upon game alone ? And if not, what are the 

 governing factors ? " 



