cousidered harmful everywhere, I must yet disagree with the Committee regarding 

 the manner iu whicli the end has to be achieved. Ooe thing we must remember, 

 namely, that the fight with these harmful animals is everlasting; the 

 species can never be quite extermiaated. For example, howewer much the public 

 have helped to the extermination of the prawn as a useful auimal, it has yet not 

 en ti rely disappeared from auy of our small fjords. It is thus a perpetual fight, 

 and we must consider who has to bear the expense iu the loug run; the ouly 

 way this eau be met is to find a profitable use of the animals iu questiou for in- 

 dustrial or other purposes, as the Committee indeed also suggest; but at present 

 we do not understand how to do this in Denmark. The conditions here are uot 

 the same as in other countries, uor can we directly introduce the results from the 

 latter into Danish conditions; these results must first be tested and studied, then 

 perhaps the right man will come who eau solve the problem, lu my opinion, 

 therefore, it would uot be right, as the Committee propose, to use 20,000 Kr. di- 

 rectly in rewards for the harmful animals mentioned indiscrimiuately and especially 

 not everywliere in Denmark, as it is quite possible, that after a uumber of years 

 have gone past we will be exaetly at the same place as we are uow, namely, that 

 we will not know whether it is of advautage to coutiuue or not; provisionally we 

 should certainly keep to experiments in small waters, as the large would assuredly 

 show no result at present. We may remember here, how strougly the war against 

 the rats had to be organised in this country, before there was auy hope of aehieviug 

 auything worth meutioning. The faet is, that it is of uo use to destroy a small 

 number of a harmful species, the remaiuder live and propagate just so much the 

 better and more rapidly; in other words, the stock remains the same every year; 

 ouly when more are exterminated thau are yearly produced, eau we 

 manage to reduce the stock, and the fight must be contiuuous. A wood 

 does not disappear from cutting dowu the trees; to obtaiu this result, more must 

 be cut down thau grow yearly, and the cutting must be continued. 



The rate of propagation of the 5 animals mentioned is however very 

 differeut, and the same is the case with their biological conditions. If, from my 

 kuowledge of these conditions, I were to mention which of them might most easily 

 be combated iu our small waters, the whelks would be the first, uext the crabs 

 and sea-scorpions and lastly, the sticklebacks and starfishes. 



The whelks (Bnccinum) are not able to swim, either as small or as adult, 

 and consequeutly cauuot spread iu this way, and crabs and sea-scorpions do not 

 propagate in several of our small, enclosed fjords; ou this accouut their numbers 

 here might probably be kept down somewhat by a constant warriug against them. 



On the other baud, I at present consider that Ihe fight with the sticklebacks 

 and starfishes is hopeless in our country. 



With regard to the whelks, I have seen this year, 1909, during my in- 

 vestigations in the Limfjord, that it would be quite useless to give rewards for 

 the number of whelks the fishermeu bring to land when fishing for plaice; this 

 uumber namely is too small a part of the stock. lustead of this a special whelk- 

 fishery might be orgauized here with hive-traps or such like. Such a fishery 

 might well be established. From a couple of motor- boats, eaeh with 2 men and 

 several hundred hive-traps, some thousands of barreis of whelks could be fished 



