394 U. S. BUREAU OF FISHERIES 



has not yet been satisfactorily explained in the case of any marine 

 species. 



)Vhile each year's study has added considerable knowledjie to the 

 store needed for rational exploitation of the mackerel fishery, the 

 problem is so complex that the ii'oal is yet far from attainment. 



With fluctuations the dominant feature in this resource and with 

 their causes due to natural conditions not subject to control by man, 

 the problem of proper utilization depends on making the most of 

 what nature provides. There are at least two problems involved in 

 ])roviding the information needed to bring about such wise use. 

 Most obviously useful is to find means whereby the fluctuations may 

 be anticipated so that fishing and distribution may be adjusted to the 

 rapidly changing volume of supply. The other is to find out what 

 age (or size) of mackerel may best be fished in order to get the 

 most of each year class, and to find means of encouraging the methods 

 of fishing that, on the average, will take such sizes. 



Considerable progress has been made in developing means of fore- 

 seeing the changes in the supply of mackerel. Pi-edictions have 

 been prepared and, except in the case of 1935, published at the be- 

 ginning of each season since 1928. Within their scope, these pre- 

 dictions have been encouragingly close to the mark but their utiliza- 

 tion by the industry has not been extensive. This appears to be due 

 to their being restricted to estimates of only the larger sizes of mack- 

 erel, and further limited to estimates of the probable results of the 

 season as a whole rather than its separate parts. Our present inabil- 

 ity to predict abundance of small mackerel (under one pound) is 

 serious because frequently a large portion of the catch consists of 

 these small mackerel, known as ""tinkers'' to the trade, and their 

 abundance often makes the difference between a good and bad season. 

 Similarly, the changes in abundance within the season often are 

 more important than the total catch for the year because the prin- 

 cipal means of adjustment is to freeze or process surplus fish; and 

 to adjust such o])erations to the season's run it is necessary to know 

 when the surplus will be greatest. For instance, dealers are loath 

 to freeze fish early in the season even when the market is full and 

 prices low, for fear that later the oversupply may be still greater 

 and prices still lower. 



To be able to predict abundance of tinkers and thus round out tlie 

 forecast service reqidres that their abundance be measured during 

 the first year of life, which in turn requires special observations at 

 sea that can be made only by means of a research ship. Work on 

 this phase had progressed to a promising stage, but ceased in 1932 

 when the Albatross II was decommissioned for lack of operating 

 funds. Although observation in this field has been discontinued, the 

 analysis of results is still under way (as above mentioned) and will 

 have important bearing on any future work in this field. 



The problem of predicting the "run" at various ])arts of the sea- 

 son is amenable to solution. There are indications that there exist, 

 within the mackerel population, different types whose habit is to 

 a{)])ear fairly regularly at certain times and places, depending on 

 their age. These peculiarities were taken into account in the pre- 

 diction for the 1935 season and pointed toward an unusually large 

 run in the offing of southern New England in the spring season 



