PROGRESS IN BIOLOGICAL INQUIRIES, 1926 625 
the mullet fishery is considered acute in North Carolina, and has, therefore, 
received first attention in that State. As a basis for effective regulation of the. 
fishery, observations on the life history of the mullet have been undertaken, and 
I shall outline for you briefly what is known from popular knowledge and from, 
my own observations of the habits of this species. 
Only two brief papers on the biology of the fish have appeared in America, 
and recently some observations on rates of growth and similar facts concerning 
an allied species have been published in Egypt; but it is surprising how little. 
attention has been paid to the mullet, despite the fact that it has been cultivated, 
in foreign countries for ages. 
The mullet is a shore species, living in rivers and estuaries where an abundant 
growth of eel grass on muddy bottoms is found. In North Carolina the mullet 
seatter over the tide flats of the extensive brackish and salt-water sounds, feed- 
ing largely on the bottom mud and its contained organic matter. During the. 
autumn months the scattering individuals congregate in schools and migrate. 
from the sounds to the open sea. It is at this time that the commercial fishery 
takes toll of the migrating schools, which are packed so densely that many 
thousands of pounds are landed at a single haul of the beach seine; such as, for - 
example, a single haul made at Beaufort in October, 1926, which yielded 62,000 
pounds. The schools are composed of fish singularly uniform in size, usually- 
of a Single age class, although in the larger fish several ages undoubtedly are. 
mingled. The early fall runs, beginning in August, usually are composed of- 
the younger fish—the 0 class—with occasional schools of the 1-year-old fish. 
In September the usual runs are of 1-year-old fish, known as “fat mullet,’ 
because the abdominal cavity is filled with rolls of white, fatty tissue. Follow- 
ing these come the older fish, or roe mullet, which dominate the fishery after 
the middle of October. Virtually all of the mullet have left the sounds by 
early November, and it is at this time that spawning is believed to occur in the. 
mouths of estuaries and in the open sea. The fish apparently do not remain in 
the open sea during the winter. The schools are observed traveling southward 
and entering the inlets again, and it is known that many of them either remain 
in the sounds or return during the late fall, for occasional catches are made 
during the cold winter months farther up the rivers in fresh water. 
These fall migrations always accompany a change in weather, marked by- 
falling temperature and northerly winds. Fishermen believe that the schools. 
run before the wind out of the sounds, for they have been observed to return to 
the sounds if the wind suddenly shifts to the southward. Inasmuch as the 
younger fish take part in this migration, it can scarcely be considered a spawn- 
ing migration; but as it comes at the time of the year when the eggs reach. 
maximum observed maturity, there may be close relationship between the two 
phenomena. At present no spawning fish have been observed, nor have the. 
eggs been taken in tow nets, but it is believed that proper means will reveal 
the presence of eggs in the open sea. As the fish with evidently mature eggs. 
are taken on their seaward migration at this time of year, spawning may be said 
to occur during November and December; and it is likely that the spawning- 
season ‘s of limited duration, as the eggs are of approximately the same develop- 
ment throughout the ovaries of the fish, and as the young appear the following 
spring in very uniform size groups. 
The larval stages of development of the mullet are unknown, but juvenile 
fish appear in the sounds about Beaufort in early February, when they are. 
from 18 to 25 millimeters in length. Fish smaller than this size are seen rarely, 
but the group increases in abundance and the larger members of it become more. 
numerous during the latter part of April, and by May even the smaller sizes 
show distinct growth. It is during April that the so-called “ metamorphosis ”’- 
occurs. The fish that formerly were silvery become pigmented over the dorsal: 
areas. They are also said to change from surface or midwater plankton foods 
to the bottom foods, and distinct growth in seales can be observed. The circuli. 
on the scales, which in the juvenile cond ‘tion are transverse, now begin to grow- 
in a more nearly concentric form, inclosing the juvenile scale so as to show a 
typical winter check. Scales from collections of these small fish made during.’ 
early March had no marginal circuli, but a collection taken on March 24, 1925, 
contained three fish with one or two marginal circuli. Another collection, on, 
March 30, contained a few in this condition; but by the middle of April the. 
scales from all the collections of fish of this size group showed varying num- 
bers of marginal circuli inclosing the so-called “juvenile scale.’ The mean. 
length of this size group increases rapidly in May and maximum. growth occurs. 
66552—27—_8 
