It was therefore more than clear that spraying at the rate of a pound of DDT to the acre pos ed a
s erious threat to the fis hes in fores t s treams. Moreove r, control of the budworm had not been
achieved and many areas were s cheduled for re -s praying. The Montana Fis h and Game
Department regis tered s trong oppos ition to furthe r spraying, saying it was ‘not willing to
compromis e the s port fis hery res ource f or programs of ques tionable neces s ity and doubtf ul
success.’ The Department declared, howeve r, that it would continue to coope rate with the
Fores t Service ‘in determining ways to minimize adverse effects.’
But can s uch coope ration actually s ucceed in s aving the fis h? An expe rience in Britis h Columbia
speaks volumes on this point. T here an outbreak of the black-headed budworm had been
raging for several years. Forestry officials, fearing that another season’s defoliation might result
in s evere loss of trees , decided to carry out control operations in 1957. There were many
cons ultations with the Ga me Department, whos e officials were concerne d about the s almon
runs. The Fores t Biology Divis ion agreed to modify the s praying progra m in every pos s ible way
s hort of des troying its effectiveness, in order to reduce risks to the fish. D es pi te thes e
precautions , and des pite the fact that a s incere effort was apparently made, in at least four
major streams almost 100 per cent of the salmon were killed.
In one of the rivers , the y oung of a run of 40,000 adult Coho s almon we re almos t completely
annihilated. So were the y oung s tages of s everal thous and s teelhead trout and othe r s pecies of
trout. The Coho salmon has a three-year life cycle and the runs are compos ed almos t entirely of
fis h of a single age group. Like other s pecies of s almon, the Coho has a s trong homing ins tinct,
returning to its natal stream. There will be no repopulation from other streams. This means,
then, that every thi rd year the run of s almon into this river will be almos t nonexis tent, until
s uch time as careful management, by artificial propagation or other means, has been able to
rebuild this commercially important run. There are ways to solve this problem—to preserve the
forests and to save the fishes, too. To assume that we must res ign ours elves to turni ng our
waterways into rivers of death is to follow the counsel of despair and defeatism. We must ma ke
wider use of alternative methods that are now known, and we mus t dev ote our ingenuity and
res ources to developing others. There are cas es on record whe re natural paras itis m has kept
the budworm unde r control more effectively than s praying. Such natural control needs to be
utilized to the fullest extent. There are possibilities of using less toxic sprays or, better still, of
introducing microorganisms that will cause disease among the budworms without affecting the
whole web of forest life. We shall see later what some of these alternative methods are and
what they promis e.
Meanwhile, it is important to realize that chemical spraying of forest insects is neither the only
way nor the bes t way. The pes ticide threat to fis hes may be divided into three parts. One, as we
have seen, relates to the fis hes of running s treams in northe rn fores ts and to the s ingle
problem of fores t s praying. It is confined almos t entirely to the effects of DDT. Another is vas t,
s prawling, and diffus e, for it concerns the many different kinds of fis hes—bass, s unfis h,
trappies , s uckers , and others that inha bit many kinds of waters , s till or flowing, in many parts of
the country. It als o concerns almost the whole gamut of insecticides now in agricultural use,
although a few principal offenders like endrin, toxaphene, dieldrin, and he ptachlor can eas ily be
picked out. Still another problem mus t now be c ons idered largely in terms of what we ma y
logically s uppos e will happen in the future, becaus e the s tudies that will dis clos e the facts are
only beginning to be ma de. This has to do with the fis hes of salt mars hes , bays , and es tuaries.
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