f > MM
COMMON TERN.
STEMNA HIRUNDO, LINN.
1'L.A'I K CCCIX. AJTOI.T.
AI.THOUOH thé Prince of MUSIGNANO hasJthought that the bird
named the Common Tern in America, differs f&oïn that beariag the
same name in Europe, and has in consequence changed its appellation
to that of Wilson's Tens, I iim of opinion that AS! difference-exists
between the Common Terns of the two Continents. The cry of both
is besides precisely similar, so ¡that ivith mo there is 110 doubt whatever
as to their identity.- .Expérience has shewn me that the .markings
or ¡White spots onthe primary quills ¿of Gulls, at one time assumed
as a criterion -by which species might be distinguished, cannot in the
least be depended on, varying, as Sigf always do, MHdividuals of
the same species, at almost iiaêh successive moult. Then why, Header,
should not Terns exhibit analogous changés'? The fact is, they do so;
and it is' almost impossible, 'on closely ïiispèctSig a dozen or imffle
specimens procured at the same period, in either country, to find two
individuals exactly Corresponding in seVeryparticular, Some have tin:
bill almost entirely black, «lïilo -others have'it more èr less fed and
black, and 'tipped \vith 'yellow. The length Of %he tail-feathers, that of
the tarsus, and the size of tin; inter-digital merâbranes, -are all fnund
to differ in some degree, if minutely compared. Ii' species are to «he
^bunded on such slight differences, an ample field is open to those
„},„ are ambitious of being discoverers. At all events, I cannot help
remarking here, that it seems to me improper to impose new names
on objects, until-it is proved by undeniable fects that they present
permanent differences.
I have' observed this spCeies along the Atlantic coast of North
Aïâériià;irôm Galveston Island in Texas to the Straits of Belle Isle
on the coast of Labrador, both in spring and in early autumn. Biit
when on the islands là Galveston Hay, in the month of -April, I saw
only a few'àïriving there from thé west ; -whereas, in thesbeginning of
May great numbers arrived there from the east, settled at once, and
commenced breeding. I felt convinced that the numbers which came
COMMON TERN. 75
from the direction of the Floridas were much greater than those which
arrived from the westward, and judged it probable that vast numbers
had at the same time left the Peninsula on their way northward.
Should other travellers observe the same or similar phenomena at the
season mentioned, it will be proved that this species does not extend
its autumnal migration so far as several others, which I observed arriving
at Galveston Island from the south-west, for example, the Least
Tern, St,mm minuta, the. Gáyense Tern, 8t. cayana, and the Black
Tern, lit. nigra.
The Common Torn commences breeding On the coast of our Middle
Districts about the 5th of May. On my voyage to Labrador, I found
its eggs on the. islands in the Gulf of St Lawrence, and especially, on
the Magdalene Islands, which I visited on the 11th of that month.
On the 18th I saw them in great abundance in the neighbourhood of
American Harbour, on the coast of Labrador, where thousands of
Terns were plunging headlong after shrimps all round us. in that
country, their eggs were deposited among the short grass, and the
places which they occupied "were but slightly scratched ; whereas on
the Magdalene Islands, where they breed on sandy ridges, slight hollows
were scooped out, as is generally the case along the eastern coast
of the United States. Their sojourn in Labrador is of short duration
; and when we were at Newfoundland, on the 14th of August,
multitudes were already passing; southward. At the same period considerable
numbers pass by an inland route from the Canadas, and all
our great lakes, travelling along the Ohio and Mississippi. While residing
at Henderson, and afterwards at Cincinnati, I had ample opportunities;
of watching their movements in the month of September.
Arid .yot, you will think it strange;, that, during their vernal migration,
I never saw one ascend any of these rivets or the streams connected
with them. Perhaps the inferior temperature of the waters, compared
with those of the océan, in the. early spring months, may induce them
to abandon their route at that season. In. «autumn, on the contrary,
when these rivers are heated and reduced in size, the Terns may find
in them an abundant supply of the fry of various fishes. It woAdd
thus appear, being corroborated by other observations which I have
made relative to migration, that species whose range is extensive, are
determined in their movements by a genial temperature and an abundant
supply of food.