is 13 days...Our analyses are s howing high concentrations of DDT in the tes tes and ovaries of
breeding birds ,’ he told a congress ional committee in 1960. ‘Ten males had amounts ranging
from 30 to 109 pa rts per million in the tes tes , and two fe males had 151 and 211 pa rts per
million respectively in the egg follicles in their ovaries.’ Soon s tudies in other areas began to
develop findi ngs equally dis mal. Profes s or Jos eph Hickey and his s tudents at the University of
Wis cons in, after careful comparative s tudies of s prayed and uns praye d areas , reported the
robi n mortality to be at least 86 to 88 per cent. The Cranbrook Ins titute of Science at Bloomfield
Hills, Michigan, in an effort to assess the extent of bird loss caus ed by the s praying of the elms ,
as ked in 1956 that all birds thought to be victi ms of DDT pois oning be turne d in to the ins titute
for examination. The reques t had a res pons e beyond all expectations. Within a few weeks the
deep-freeze facilities of the institute were taxed to capacity, so that other specimens had to be
refused. By 1959 a thous and pois oned birds from this s ingle community had been turned in or
reporte d. Although the robin was the chief victim (one woman calling the ins titute reported 12
robi ns lying dead on he r lawn as s he s poke), 63 different s pecies were included among the
s pecimens examined at the ins titute. The robins , then, are only one part of the chain of
devas tation linked to the s praying of the elms , even as the elm program is only one of the
multitudinous spray programs that cover our land with poisons. Heavy mortality has occurred
among about 90 s pecies of birds , including thos e mos t familiar to s uburbanites and amateur
naturalis ts. The populations of nes ting birds in general have declined as much as 90 per cent in
s ome of the s prayed towns. As we s hall s ee, all the various types of birds are affected—ground
feeders, treetop feeders, bark feeders, predators. It is only reas onable to s uppos e that all birds
and mammals heavily dependent on earthworms or othe r s oil organis ms for food are
threate ned by the robins ’ fate. Some 45 s pecies of birds include earthworms in their diet.
Among the m is the woodcock, a species that winters in southern areas recently heavily sprayed
with heptachlor. Two significant discoveries have now been made about the woodcock.
Production of young birds on the New Bruns wick breeding grounds is definitely reduced, and
adult birds that have been analyzed contain large res idues of DDT and heptachlor. Already
there are dis turbing records of heavy mortality among more than 20 other s pecies of ground-
feeding birds whos e food—worms , ants , grubs , or other soil organisms—has been pois oned.
Thes e include three of the thrus hes whos e s ongs are among the mos t exquis ite of bird voices ,
the olive-backed, the wood, and the he rmit. A nd the s parrows that flit through the s hrubby
unde rs tory of the woodlands and forage with rustling sounds amid the fallen leaves—the s ong
s parrow and the white-th roat—thes e, too, have been found among the victims of the elm
sprays. Mammals, also, may easily be involved in the cycle, directly or indirectly. Earthworms
are important among the various foods of the raccoon, and are eaten in the s pring and fall by
opos s ums. Such s ubte rranean tunnele rs as s hrews and moles capture the m in numbe rs , and
then pe rhaps pas s on the pois on to predators s uch as s creech owls and barn owls.
Several dying s creech owls were picked up in Wis cons in following heavy rains in s pring, perhaps
pois oned by feeding on earthworms. Hawks and owls have been found in convuls ions—great
horned owls , s creech owls , red-s houldere d hawks , s parrow hawks , mars h hawks. Thes e may be
cas es of s econdary pois oning, caus ed by eating birds or mice that have accumulated
insecticides in their livers or other organs. Nor is it only the creatures that forage on the ground
or thos e who prey on the m that are endangered by the foliar s praying of the elms. All of the
treetop feeders , the birds that glean their ins ect food from the leaves , have dis appeared from
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