10 U. S. BUREAU OF FISHERIES. 



Observations were first undertaken in White Lake, near the Gulf, 

 where the Superintendent of Fisheries had previously conducted in- 

 vestigations of the spawning of pacldlefish. Owing, however, to 

 changes having occurred in the lake due, it was believed, in part to 

 drought and removal of water from the lake for irrigation of rice 

 fields and in part to overfishing, no pacldlefish were obtained. The 

 investigator then proceeded to Natchitoches and Red River Parishes, 

 where better conditions were encountered both in the Red River and 

 in the Oxbow Lakes adjacent to it. Here over 300 paddlefish were 

 taken, of which 17 were mature females with eggs and 3 were mature 

 males. No females with eggs free or running were found, but one 

 spent female was taken April 2 and another April 11. 



An experiment was made in retaining large paddlefish in a good- 

 sized inclosure formed by placing fine-meshed wire netting across the 

 mouth of an arm of a bayou. Although no results in propagation 

 were obtained, it was demonstrated that paddlefish could be kept in 

 such an inclosure for two or three months at least. It was found also 

 that by tethering a paddlefish by a line 5 or 6 feet long to an empty 

 gallon jug the fish could be kept in good condition and recovered at 

 will. 



It was observed that while large mature fish may be found in iso- 

 lated lakes, young paddlefish are found only in those lakes or bayous 

 which have a connection with the river. Nevertheless, it may be that 

 pacldlefish propagate successfully in isolated lakes of very large size, 

 such as White Lake (in former years), where the chance of avoiding 

 enemies is better. Fish retained in small pens or tied with a line were 

 frequently attacked and killed hy turtles, principally the soft-shell 

 turtles. The turtle evidently sought the eggs, since this was the first 

 part of the fish to be devoured, and turtles taken in the vicinity were 

 observed with paddlefish eggs in mouths and stomachs. 



In the spring of 1920 more attention was given to river fish than to 

 those landlocked in lakes, but on account of flood conditions only a 

 very small number were secured and none of these were mature males. 

 While awaiting more favorable conditions, experiments were con- 

 tinued upon the lake fish, the eggs being treated by the artificial fecun- 

 dation method successfully used with sturgeon. Eggs in sand re- 

 mained free of fungTis, but no development was observed in any of 

 them. It is believed that success depends upon securing river fish 

 (among which only have spent females been found), but a favorable 

 season without too much high water is necessary for this. 



LIFE HISTORIES OF MARINE FISHES, 



One of the most important conditions of intelligent exploitation 

 or protection of the great fisheries of the seas is a knowledge of the 

 life histories of the species. Such knowledge is difficult to obtain, 

 since it is manifestly impossible to observe directly the daily and sea- 

 sonal movements of inclividual fish that possess the freedom of the 

 sea. The desired knowledge can be accumulated but slowly through 

 the pursuit of oceanographic studies and the continual collection of 

 fishes under conditions of accurate record, with especial reference to 

 eggs and larvae. The material and the data accumulated at any one 

 time may tell no useful story, but when there has been gradually 

 gathered together a great store of materials, many of the several 



