416 
FOREST A X 1) S T R E A M 
July, 1918 
TICKS AS PARASITES OF GAME ANIMALS 
THEIR DANGER TO HEALTH LIES NOT SO MUCH IN BLOOD-SUCKING PROPENSITIES 
AS IN THE MALIGNANT FORMS OF GERM LIFE WHICH THEY FREQUENTLY CARRY 
T HE following letter from Mr. Arno J. 
Vivian, of the Culver Military Acad¬ 
emy, Lake Maxinkuckee, Indiana, is 
of much interest in its relation to the dis¬ 
tribution and relative abundance of small 
mammals. Unfortunately, little is known 
regarding ticks and other ectoparasites of 
game animals, except that hardly any spe¬ 
cies of the latter is free from their rav¬ 
ages, and that some of these parasites have 
very curious life histories, living on dif¬ 
ferent kinds of hosts during their young 
and their adult stages. 
“Editor of Forest and Stream :— 
In the last couple of years I have no¬ 
ticed a very pronounced decrease of the 
red squirrels in this section of the coun¬ 
try, and I think I have at last found the 
reason for this. As I was walking the 
other day I noticed a squirrel lying on 
the ground gasping for breath. I picked 
it up and saw a number of little gray 
objects on its head and back. Upon ex¬ 
amining one of these I found it to be a 
gray tick or bug with a red head and 
legs, and which seemed to be sucking the 
blood from the squirrel. 
“I would like very much to know if 
you could give me the name of this 
little animal, and tell me whether it is 
a common pest or not.” 
From Mr. Vivian’s meager description of 
the ticks it is impossible to name them 
with certainty, but they doubtless belonged 
to one of several species of blood-sucking 
Acarina, of the genera Ixodes or Hccma- 
physalis, known to infest rodents and other 
mammals. Young ticks of the latter genus 
often live upon birds, but the adults are 
usually found on rabbits. In New Hamp¬ 
shire I once accidentally caught a hermit 
thrush in a trap set for shrews, and the 
head of this bird was completely covered 
with tiny ticks which were identified as the 
young of Hcemaphysalis leporis-palustris. 
The thrush had been so badly injured by 
the trap that I had to kill it, and as soon 
as it became cold the parasites all left its 
body. This was probably due rather to the 
coagulation of the bird’s blood than to the 
lowering of its temperature, for related spe¬ 
cies of ticks live on the cold-blooded 
turtles, lizards, and snakes as well as upon 
warm-blooded animals. 
Rabbits and hares are quite commonly 
speckled with these ticks, especially in the 
autumn, but they seem to be of rarer oc¬ 
currence on squirrels. They often cluster 
thickly about the long ears of their rabbit 
hosts, and are present in various sizes from 
pinheads to buckshot. On one occasion I 
HE Natural History Department 
has been for nearly half a 
century a clearing-house for infor¬ 
mation of interest to all. Our read¬ 
ers are invited to send any questions 
that come under the head of this de¬ 
partment to Robert Cushman Mur¬ 
phy, in care of Forest and Stream. 
Mr. Murphy, who is Curator of the 
Department of Natural Science in 
the Brooklyn Museum, will answer 
through these columns. [Editors.] 
picked up a young Long Island cottontail 
rabbit which was so completely covered 
with these irksome blue pests that I doubt 
whether it could have survived the loss of 
blood and the irritation to the skin. 
It is well known that one or more of our 
North American ticks can be no less 
troublesome to human beings than to small 
wild mammals. When the “wood-ticks,” as 
they are called, get a firm yet subtle and 
painless hold, they cannot be dislodged 
without pulling the body of the creature 
from its buried head, which remains in the 
skin and causes a persistent itching, some¬ 
times for months afterwards. 
RECORDS OF WINTER BIRDS 
OF PREY 
HE winter of 1917-18 was marked by 
an exceptional abundance of destruc¬ 
tive, northern birds of prey, such as 
goshawks, horned owls (including the 
arctic and western varieties), etc., in vari¬ 
ous parts of the New England and cen¬ 
tral states. In southern Connecticut one 
gamekeeper is reported to have trapped and 
shot 225 hawks, mostly goshawks, "and 76 
owls, mostly great horned owls. A Provi¬ 
dence, R. I., taxidermist is furthermore 
said to have received upwards of fifty 
goshawks for mounting. 
It would be a matter of much interest, 
with a bearing upon the war-time conser¬ 
vation of the nation’s game resources, if 
readers of Forest and Stream would send 
their records of all kinds of birds of prey, 
made during the last winter, to the editor 
of this department. The data might then 
be summarized and published in these pages 
next autumn so as to be available for com¬ 
parison with the hawk and owl invasion 
during the winter of 1919-1920. 
But the worst danger from ticks is not 
the mere annoyance that they cause, and 
I am inclined to believe that healthy wild 
animals seldom suffer prolonged ill effects 
from ordinary and equally healthy ticks, 
which are of normal occurrence upon them 
and which drop off of their own accord 
when they have become sufficiently inflated 
with the blood of their host. But, on the 
other hand, ticks, like yellow-fever mos¬ 
quitoes and tsetse flies, are potential car¬ 
riers of disease. Within their bodies they 
sometimes harbor various species of blood 
parasites—single-celled animals which cause 
dangerous fevers in man and the lower 
animals. “Spotted fever” and “biliary 
fever ’ are only two of the maladies orig¬ 
inated by organisms introduced into the 
blood by ticks. It has been estimated that 
during one year (1907) one hundred mil¬ 
lion dollars’ worth of cattle were lost in 
the United States through the ravages of 
tick-borne diseases. Probably whole races 
of wild animals have in the past been ex¬ 
terminated in the same way, and we may 
he sure that if the diminution in the num¬ 
ber of red squirrels recorded by Mr. Vivian 
had any relation to the presence of the 
ticks, the rodents were killed through in¬ 
oculation with a fever or plague and not 
because of the loss of blood, which was 
trifling and of little importance. 
As regards the life history of ticks, the 
female, which alone becomes distended with 
blood, eventually drops from her host to 
the ground and proceeds to lay her eggs. 
These are enormously numerous; as many 
as twenty thousand have been counted! 
The mother then dies. When the young 
ticks hatch, they climb up adjacent vegeta¬ 
tion and await the approach of their host. 
Time is no object with them, for they are 
capable of living for months or even years 
without food. A certain proportion of 
them finally achieve a contact with some 
bird or other suitable animal, and at once 
work through the feathers or fur and bury 
their mouth parts in the skin. When they 
have sucked blood for an appropriate length 
of time they again drop off and undergo a 
metamorphosis resembling that of insects. 
(I may here insert that the ticks are, of 
course, not insects but belong to the same 
group as the spiders and mites). After the 
completion of the metamorphosis, the ticks, 
which now for the first time can be distin¬ 
guished as males and females, repeat their 
tactics in search of an unfortunate victim 
from which to suck more blood, and per¬ 
haps to give in return a mortal disease. 
R. C. M. 
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