REPORT OF COMMISSIONER OF FISH AND FISHERIES. CXXV 



The Spanish mackerel were never abundant, and in the beginning 

 the prospects seemed very discouraging, but about June 24 somewhat 

 better runs began. The small amount of spawn taken, however, was 

 not due entirely to the scarcity of fish. The difficulty arose mainly 

 from the fact that the fish appear to spawn chiefly at night or in the 

 early evening, and when the traps were hauled in the morning the 

 ova sacs were generally empty. The great pressure produced by the 

 lifting of the nets and the violent struggles of the fish when they are 

 closely massed together may also be held partly accountable for this 

 result. The experience gained this season in the collecting of the fish 

 leads to the conclusion that the pounds as run for commercial purposes 

 can not be relied upon to furnish a large supply of spawn, and the use 

 of gill nets proved an entire failure, as described in the last report. 

 In the event of extensive operations in the hatching of this species it 

 would, therefore, be greatly to the advantage of the work if one or 

 more pounds could be controlled entirely in this interest, in order that 

 they might be tended and the fish removed at the proper times to 

 insure the retention of the spawn and milt. Such an arrangement 

 could readily be made. The most satisfactory fishing-ground was 

 found at the mouth of Hungers Creek, where there are also excellent 

 facilities for the establishment of an inexpensive hatching station. 



The spawn of the Spanish mackerel does not all mature at the same 

 time, and each of the full ovaries examined contained eggs in all stages 

 from the ripe condition down to the minute, nucleated, cell-like eggs 

 of incipient development. Each fish, even under the best conditions, 

 yielded only a comparatively small amount of mature eggs, the 

 greatest number taken from a single individual having been 60,000, 

 and this was far in excess of the usual experience. It is impossible to 

 reconcile this result with the figures given in connection with earlier 

 experiments respecting the Spanish mackerel, made in the same 

 locality, when over a million mature eggs were sometimes credited to 

 a single fish, but this much can be said, that the observations made in 

 1892 were conducted with great care, and it is considered that they 

 may be entirely relied upon. It is also noticed by Mr. Moore that the 

 two sexes seemed to school more or less separately, and of the speci- 

 mens secured the males greatly exceeded the females in numbers. 



The experiments appeared to indicate that it is immaterial whether 

 a constant current of water is maintained in the hatching apparatus or 

 not, so long as the jars are kept scrupulously clean and are not over- 

 crowded. The good eggs are all hatched before they can be affected 

 by the decomposition of a few dead ones, when the fry can be removed 

 to a place of safety. The jars should be made of glass or at least have 

 enameled surfaces to prevent the rupture of the egg membranes, which 

 are especially delicate in this species. The tidal cod jars were employed 

 with best success on the Fish RaivJc, not more than 60,000 eggs gener- 

 ally being placed in each. One small lot of eggs treated in a jar of 

 this character, with quiet water, hatched to the extent of 90 per cent. 



