114 
BULLETIN OF THE BUREAU OF FISHERIES 
Date 
Number 
Size 
Date 
Number 
Size 
Jan. 24, 1921 ... 
1 
Milli- 
meters 
57 
Jan. 17, 1916 . . 
14 
Milli- 
meters 
50-60 
Jan. 26, 1921. 
1 
52 
Jan. 18, 1916 
2 
48-50 
Mar. 27, 1921. . . 
3 
52-59 
Feb. 19, 1922 
2 
54-57 
Mar. 2S( 1921... 
i 
57 
Little is known of the rate of growth of the American eel or the approximate age at which it 
reaches sexual maturity and returns to salt water. Some attempts have been made by European 
investigators to determine the rate of growth and age of the European eel by an examination of 
the otoliths, the centra of the vertebrae, and the scales. Information derived from these studies 
indicate that the life of the eggs and larvae may be two years (the American eel, however, is said to 
require only one year to pass through the metamorphosis), and that they probably have an aver- 
age length of IY 2 inches when 6 years old, and that at the age of 9 years the average length of the 
male is 14 inches and that of the female 15Y inches. Some evidence has also been obtained which 
indicates that maturity is reached at from 7J^ to years of age. What becomes of the eel after 
it has spawned in mid-ocean also is not known, but it is generally supposed that it dies. 
It is impossible to segregate eels into age groups based upon size, for all sizes are well repre- 
sented in the catch of collecting seines. Commercial seines and nets have a mesh of such size that 
the smaller eels escape, so that data from this source are worthless as a means for determining rate 
of growth. However, our finest-meshed seines have caught enough very small eels so that some 
idea of the early growth may be had. It has already been pointed out that the "glass eel” that 
reaches our coast during the winter (January to March off the Chesapeake; as late as April in the 
Gulf of Maine) has a length of from 48 to 60 millimeters and is about 1 year old. The following 
catches of young eels that have passed the glass stage and possess the pigment of the adult have 
been made in Chesapeake Bay: 
Date 
Number 
measured 
Inches 
Date 
Number 
measured 
Inches 
2 
2. 4-3. 1 
Sept. 30 
1 
3 
3 
2.3 
Dec. 20 
1 
2.9 
1 
2.5 
Apr. 18 
4 
4. 6-5. 5 
3 
2. 7-3. 9 
Apr. 24 
6 
4. 4-6. 5 
July 23.. 
3 
6.9 
Assuming that the fish have been grouped correctly in the foregoing table, the increase from 
one April to the next is from about to 5 inches, the greater length being attained when the eel 
is a little more than 2 years old. 
The fresh-water eel is very common in the Chesapeake region, and in many places it is abundant 
in brackish water at the mouths of rivers and creeks. 
The eel was considered so destructive of other fish that the legislature of Maryland, in 1888, 
passed an act and appropriated funds providing for the destruction of this fish. In 1892 and 1893 
one-fourth of the funds appropriated for the use of the State fish commission was set aside for the 
destruction of the eel (Sudler and Browning, 1893, p. 27). The oak -split eel pot, baited with "fresh 
offal of any kind,” was utilized in the capture of the eels. According to the report of the com- 
missioners of fisheries of Maryland for 1892 and 1893 (p. 27), $3,413.25 were expended during these 
two years for destroying eels. A total of $80.77 was realized from the sale of the eels thus taken. 
No information concerning the number of eels destroyed or marketed is given. The work was 
discontinued in the following year. The effects upon the abundance of the eel and other fish, if 
any, which were brought about through the attempted destruction of eels, is not stated. 
The following incident, which appears to be worthy of note on account of the difficulty with 
which an eel, because of its “slipperiness,” is captured and retained after capture, was made by 
the junior author, whose field notes we quote: 
