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BULLETIN OF THE BUREAU OF FISHERIES 
water as for example in South Bay, Long Island, setting occurs from the bottom to 
nearly high-water mark, while in South Carolina and Georgia the set is found chiefly 
between low and high water marks and not below low-water mark. 
On a given area of bottom in Milford Harbor the setting was found to be unevenly 
distributed and varied in intensity according to the distance from the spawning bed 
and the depth of water. In the harbor the set was found to occur on such areas as 
are covered with water when the tide is 2 feet above mean low-water mark, with the 
exception of a small portion above station No. 1, where setting rarely occurs because 
of the discharge of fresh water. In 1925 a set of commercial value was found prin- 
cipally within a radius of 300 yards from the spawning bed, the number of spat 
ranging from 5 or 6 spat per shell on the outside edge to 200 and 300 per shell in the 
central portion. The spat were most abundant on shells planted over the spawning 
bed and within approximately 100 yards of its center. The concentration of spat 
at the 100-yard circle averaged 50 per shell. Though setting occurred practically 
the same distance upstream or above the bed as it did below it was found to be of 
slightly greater intensity in the areas lying below or toward Long Island Sound. 
The horizontal distribution of the set in relation to the spawning bed clearly shows 
that the oyster larvae remain close to the place where they were produced. 
EXPERIMENTS IN SEED-OYSTER COLLECTION 
Various types of spat collectors and materials suitable for the attachment of the 
oyster larvae were used during the past four years in Milford Harbor. In 1925 birch 
brush, glazed tiles, and wire baskets filled with oyster and clam shells were used. 
In 1926 triangular crates made of lath were filled with shells and set out on the tidal 
flats in various formations. In 1927 and 1928 wire bags filled with oyster shells 
were used on a much larger scale and were tested out in Milford Harbor and several 
other localities in Connecticut. In 1929 experiments were conducted with partition 
type collectors. In order to simplify matters each summer’s experiments will be 
discussed separately as to the methods employed and results obtained with each 
type of collector. 
In 1929 a new type of collector was developed for the gathering of seed oysters 
in heavy setting regions. This device consisted of a series of waterproof cardboard 
partitions, similar to an egg case filler, which was covered with a thin coating of 
cement. It gave a total collecting surface of approximately 1,000 square inches. 
In Great South Bay, Long Island, 1,000 of these partitions were planted by the 
Bluepoints Co., and a similar number were set out by the Connecticut Oyster Farms 
Co., on the tidal flats in Milford Harbor. 
In each region the partitions proved to be very satisfactory and collected from 
2,000 to 25,000 spat on a single partition. The advantage of using seed collectors 
of this design lies in the fact that they are inexpensive and suitable for collecting large 
numbers of spat which can be separated easily when a few months old. The supply 
of oyster shells has been steadily decreasing each year and consequently the develop- 
ment of partitions as a practical substitute is significant. 
The partitions are superior to shells principally because they can be broken up 
or separated thus saving the spat after they have grown for two or three months. 
For full description of the preparation, use and planting of partitions for the 
collection of seed oysters the reader is referred to Bureau of Fisheries Document 
1076, “Improved Methods for the Collection of Seed Oysters” by H. F. Prytherch. 
