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In a somewhat similar mannerthe cod of the AtlanticCoast are being investigated.We are learning many importantthings about their lifejPAGE FOUR THE COLLECTING NETConservation Work ofBureau of Fisheries(Continued from Last lisue)history and their migrations.From 1923 to 1926, over 36,000Icod, haddock and pollock weretagged off the coast of NewEngland. Approximately 1600of these were recaptured. Therecan be no question that tl;e dataobtained will be of incalculablevalue if the time ever comeswhen it will be necessary to protectthese fisheries. Fortunatelythere is no evidence at thepresent time that depletion istaking place, but the great fishingbanks are being exploitedmore and more each year, notonly by the fishermen of theUnited States and Canada butalso by European fishermen.Division of Fish CultureVery early in its history thebureau undertook the propagationand distribution of themore important food and gamefishes. The hea,;est mortalityamong fishes occurs duringtheir early life. Just as thereis a greater death rate amongbabies than among older peopleso there is a greater death rateamong young fishes during thefirst few days or months oftheir lives. Artificial propagationis designed to eliminate thehazards of life in the earlystages of fish development.From asmall beginning thisservice has now come to be oneof the largest in the Bureau andannually millions of young fishare reared and distributed inthe interior and coastal watersof the United States. Duringthe years 1925 and 1926 theannual distribution of fish of allspecies and stages of developmenttotaled approximately5,232,000.000 and of these all butabout 108,000,000 were of directcommercial importance. In theproduction of this enormousnumber of young fish the Bureauoperated 70 separate fishcultural stations. An importantphase of this work has beenthe cooperation between the bureauand the various Stateswhich have thus far taken anactive interest in practical fishculture. Such cooperative workhas been varied in its nature,involving in some instancesjoint operations at egg-collectingstations, and frequent exchangeof eggs of various .speciesfor the convenient distributionof the resulting fish. Inother cases the bureau hasloaned its distribution cars toenable the States to quickly andjconomically distribute the fishfrom their hatcheries. In stillother cases the bureau has beenable to incubate fish eggs in itshatcheries acquired by Statesnot operating hatcheries, theresulting fry or fingerlings beingplaced at the disposal of theState officers. Further cooperativework has been carried onin conjunction with clubs andindividuals who have establishednurseries for rearing tolarger size fish furnished by thebureau. The net result has beento increase the fingerlings productionfor 1926 two fold overthat for 1925.In addition to the work ofpropagation, this division 'hasdeveloped methods of rescuingfish from the pools left by recedingriver waters followingspring floods. This work isconducted mainly in the upperMississippi Valley and about150,000,000 fish are rescuedeach year from pools wherethey would undoubtedly die andare returned to the main river.This is one of the most importantand popular features of thebureau's work in fish conservation.During the year 1922this work attained its greatestvolume in the number of fishhandled. A total of nearly180.000,000 fish was thus salvagedand either returned to theoriginal waters or delivered toapplicants for planl-ing in adjacentterritory.The salvagedfi.shes comprise practicallyeveiT useful species common inthis region. There is considerablefluctuation in the volumeof this work, which depends uponclimatic conditions and thestage of the river.The division of fish cultureand the division of scientific inquiryhave cooperated for anumber of years in the developmentand conservation of thefresh-water mussels of the MississippiValley. The shells ofthese mussels form the raw materialwhich is used in the manufactureof pearl buttons—anindu.stry of considerable importanceproducing an annual outputof about $7,000,000. Theyoung mussels during the firsttwo or three weeks of their livesare minute microscopic animals.During this stage of their existencethev live on the gills ofcertain fishes. It is necessarythat they find the proper hostfish soon after they are releasedfrom the narent or else theyperish. The young mussels dopractically no harm to the fishon which they are living andthe Bureau has aided the maintenanceof the supply of musselsby bringing the young musselsand the proper host fishes together.This work is donemainly in connection with therescue operations. At the timethe fish are taken from the poolsand before they are returned tothe river some are placed in atank of water in which enormousnumbers of the minutelarval forms of the mussels havebeen liberated. In a very fewminutes hundreds of these haveattached themselves to the fishwhich are then released. Intwo or three weeks the larvalmussels will free themselvesfrom the host and will drop intothe mud a;t the bottom of therivers and smaller streamswhere they may develop intoadult mussels of commercialsize.Division cf Fishery IndustriesThe activities of this divisionare directed along several lines;the gathering and study of fisherystatistics, collecting data onthe methods of the fisheries, andtechnological work looking towardthe improvement of methodsof preparation and merchandisingof the fishery productsand of the use of their byproducts.The importance of adequatefishery statistics in a programof conservation, can not be overestimated.It is only by the collectionand study of such statisticsthat the diminution inthe stock of fish may be detectedbefore it has progressed tosuch an extent that it is apparentto fishermen. In that eventit has already proceeded to sucha degree that a rehabilitationof the stock is very difficult, ifnot impossible. The division offishery industries attempts tocollect as complete statistics asis possible with its limited personneland funds. In order tocanvass the fisheries of theUnited States, it has been necessaryto divide the country intoa number of sections whichare canvassed at intervals offive or more years. The sectionsare as follows: The NewEngland states, the Middle Atlanticstates, the South Atlanticstates, the Gulf states, the Pacificstates, the Great Lakes andthe Mississippi River and tributaries.It is recognized that statisticscollected at such intervals arereally not adequate for conservationpurposes. In view ofthis fact, special systems of statisticshave been instituted forsome of the more importantfisheries, especially those of internationalcharacter. Theseconsist of statistics which arepublished monthly of vessellandings at the principal NewEngland ports, and at Seattle,Washington, and also annualcanvasses of the shad fisheriesin the Hudson and PotomacRivers. The statistics in allcases include information onthe number of men engaged andthe gear employed in order thatthe intensity of the fishing effortmay be evaluated. Suchdata are of great value and providethe only source of informationwhich we have of thepresent tendency of our fisheries.They foi-m the foundationon which must be based thepractical application of measuresfor conservation.Supplementing these statisticson landings of fish there isan annual report on the productionof canned fishery productsand by-products, and a monthlypublication of the amounts offish frozen and held in cold storage.The latter are collected bythe Department of Agriculturethrough its Bureau of AgriculturalEconomics. These serveto furnish information of valuein following the development ofthese two very important phasesof the fi.shing industries.The extent to which fisheryproducts may be made availableto the people of the country isdetermined to no small extentby the price paid by the ultimateconsumer. This price is determinedin part by the cost offishing operations and this inturn is determined in part by.the cost of gear. Within thepa.st few years the division offishery industries has conductedextensive investigations lookingtoward the improvement of netpreservatives. It has developeda method of prolonging the lifeof fish nets by means of a coppercompound which has foundconsiderable favor, and is beingused ratlher extensively. Fui--ther experiments are being conductedalong these lines.Studies of the basic principlesinvolved in the preservationof fish with salt have madepossible the successful saltingof fish at higher temperaturesand therefore in wanner climates.Such methods are noAV incommercial practice. Improvedmethods for freezing fish forstorage land transportation havebeen worked out. Such improvementswill tend to reducethe losses during shipment,which are wasteful of a valuablefood product and which arean important factor in increasingthe cost of fish to the consumer.Improved mpfhods havebeen developed for the canningof sardines which, it is believed,will make for a better pi-oduct;possibly produced at a lowerprice, and which will tend to reducethe waste of this valuablefish.These examples are illustrativeof the technological workof this division. The importanceof this work from theviewpoint of conservation liesin the fact that the developmentof better methods of handlingfishery products will preventunnecessary waste and will improvethe product and at the(Continued on Page 8)