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Show TAG CRABS AND LOBSTERS Government Does It So That Migrations Migra-tions May Bo Traced. Ingenious1 Government scientists havo devised a novel nnd curious means of keeping track of tho movements of marine ma-rine animals such, for example, as tho edible crab, whose perambulations in its native waters have been found worth studying, says tho Chicago Chronicle It has been ascertained that, for some unknown un-known reason, nearly all of the femalo crabs In tho Chesapeako are In tho lower low-er bay a fact In all probability having something to do with the density of tho water and the United States lisherles bureau bu-reau wants to learn whether any migration migra-tion occurs, of males or females, and, If so, at what season of the year. Information Informa-tion on this point might be useful in tho experiments now contemplated for breeding breed-ing these crustaceans, which aro threatening threat-ening to become scarce, artificially. It Is proposed to catch a few dozens of both sexes and fasten securely to each specimen a small copper tag bearing a number, thereupon restoring tho animals to their freedom. Kach tag would also bear a request for Its prompt return to the lisherles bureau at. Washlnston by anybody chuncing lo capture the wearer. The tags being numbered consecutively and memoranda being kept of the placo at which each crab was liberated, the Journey mado by thu crab between tho date of consigning It to the water and the dato on which It was caught would be exactly known. This method has been practiced with considerable success in the cases of lobsters, lob-sters, ,179 of which were liberated recently recent-ly In Buzzard's bay and adjacent waters. Notwithstanding the fact that the Greek and Portuguese fishermen who own most of the lobster pots in that vicinity were disposed to retain the lags in their possession pos-session for use as charms, seventy-six were returned. "When tho data thus supplied sup-plied wore reckoned out much useful knowledgo about the movements of the anltmtjs was secured nnd Incidentally ll was discovered that these crustaceans are much more rapid t:velers than had been supposed. Some of those released were found to have Journeyed -ten miles or moro within forty-eight hours. One naturally thinks of tho lobster as a slow-moving creature. It Is such. Indeed, en land, but In the water It can not only run with great rapidity, but wlin also with a swiftness that would do credit to a fish. It Is known that lobsters migrate from the shnllows lo the deeper water In winter to escape the cold, returning shoreward In the spring; but It Is likely that they travel at other times in pursuit pur-suit of the food of which they aro most fond such, for Instance, as the shellfish, which they crush with their powertul claws. A lobster, of course, has one claw for crushing and another for cutting, tho two being quite unlike In structure as anybody may see for himself. Tho tags wero fastoned to the lobsters noses. "Whon experiments were made by tho fisheries bureau, uol long ago. for tho purposo of keeping tub on salmon after they went to set. the pieces of copper were attached, necessarily, lo the back tins of the llshes. The salmon, ns everybody every-body knows, Is a deep aea llsh. which runs up the rivers to spawn. Hatched In the upper waters of a stream, tho young salmon makes Its way to tho ocean and atavs there until It Is ready to reproduce. repro-duce. Its species. But what does It do meanwhile? How far doca It go away from the mouth of its native river? How old Is It whon It seeks fresh water to spawn? These wero ono or two of tho questions which tho exports wero unablo to answ.er. Bv tagging many of the young fishes, however, and liberating them, tho re-qulsllo re-qulsllo Information was obtained with the utmost accuracy. TCach tag bore a date showing the age of uny adult tlsh salmon that was afterward caught thus ticketed. The age of spawning wsih found to vary a good deal with the species, but tho tacs used In a number of rivers on tho west const proved that these Jinny creatures never go far away from tho mouths of the stream In which they wero hatched and to which thoy return when they are old enough to breed, Some of the tugged salmon, by the .way, wero caught in the deep ea off the coast of fishermen. It used to be supposed that shad made an annual migration up the Atlantic coast, entering the rivers successively as they proceeded northward; but now It Is known thnt they spend most of tho year, like the itnlmon. In the deep sea oft tho mouths of tho rivers In which they were hatched, feeding on the bottom and never zolng verv far away When they arc old enough they enter the rivers to spawn. Perhaps some more fncts of Interest nnd value might be ascertained about tho shad by utillzlrg tho tagging plan with them. |