Even the casual visitor to many of our small Tidewater Virginia fishing communities will see signs of diminishing prosperity. A prosperous era has been succeeded by a period of lower economic and social levels.
What are the underlying causes of this declining trend? In facing this problem, so broad in its scope and so serious in its effect, the Virginia Fisheries Laboratory has, during the past year, effected an organization for analyzing conditions in our commercial fisheries and for disseminating facts about them and the need for their conservation

Newcombe, Curtis L.

English

College of William & Mary: W&M Publish

W&M ScholarWorks VIMS Articles Virginia Institute of Marine Science 1941 Conserving our salt-water fisheries: work of the Virginia Fisheries Laboratory Curtis L. Newcombe Follow this and additional works at: https://scholarworks.wm.edu/vimsarticles  Part of the Aquaculture and Fisheries Commons \' 1111.:iHUlA r1v111...,u'"'"' -.. -: -YORKTOWN, VIRGINIAVIRGINIA FISHERIES LABORATORY AND DEPARTMENT OF BIOLOGYCOLLEGE OF WILLIAM AND MARY CONTRIBUTION NO. 5 ,,., ,,  .. -CONSERVING OUR SALT-WATER FISHERIES WonK op THE VIRGINIA FISHERIES LABORATORYCURTIS L. NEWCOMBE . Reprinted from THE COMMONWEALTH, 5' 6z...) : December, 1941. Work of the Virginia Fisheries Laboratory 1 By CUR TIS L. NEWCOMBE Direcwr EVEN the .casual visit·or to _many _of oui small 1 1d ewate r V1rg in1a f1 sh1n,g communi ties will see signs of diminishing prosperity. A prosperous era has been succeeded by a period of lowe r economic and social levels. What are the underl ying causes of thi s declin ing trend ? In facing thi s problem, so broad in its scope and so serious in its effect, the Virg inia h sheri cs Laborato ry has, during the past yea r, effected an or-ganization for analyzing conditions in our commercial fisheries and for disseminat-ing facts about them and the need for their conservation. Virginia has a big stake in the seafood business and with proper methods of utilization this asset may be greatly in-creased. The fi sheries of Accomack, Math -ews , Northumberland , and Lancaster counties, the four largest -producing coun -ties of Virginia, have an average value per co_unty of about half a million dollars an -nually, the average popubtion of these count ies being approximately I 5,000. Of the tota l vo lume of production of the t\\O Chesapeake states, Vi rginia produced in 19:\9 more than 80 per cent, or over 262, · 000,000 pounds of seafood and other marine products, va lued at four and one-half million dollars. Mary land' s output was about 6 1,000,000 pounds, wo rth abo ut two and one-half million dollars. Wh ile some of Virg inia's fi sheries are expanding, as a resu lt of increased de-mand or better gear, others are experi -encing downward • trends of production . 'Co11t,·ib111io11 No . 5 of the Virg inia Fisheries Laboratory and Depar tment of Biology, Co ll ege of Wi ll iam and Mary. ' The Yo rklow11 Lci/Jorc1torv For exunple, the shad fis hery has shown a decline from more than 6,000,000 pound~ in 1929, valued at nea rly one and one-half mil lion doll ars, to around 3,-500,00D pounds in l939, valued at one-third of a million dollars. The General Assembly of 194 0, recog-nizing the need for conservation studies of the marine resources of Virginia, ap-p:-opri, ted fund s to the Commission of Fisheries and the College of William and Mary c0 initiate this work. The late G. Walte1 Mapp, then commiss ioner of fi sh-eries and rector of the college, saw and appreciated the great part that scientific manag~ment is destined to play in the conscrn tion anLI ade(1uate utilization of the fishery resources and the advantages of bringing the facilities of the commis-sion and the co ll ege to bear on the ~olu-tion of the problems of the fi sheries . Un-der his influence and that of President John Stewart Bryan, the Virginia Fish-eries Laboratory was established on July l , 19'1 0, to develop and conduct the re-search and educational prog rams. Field studies are centered at the laboratory in [ l ] Yorktown and the teaching work is con­ducted at the College of William and Marr in Williamsburg, experimental work being carried on in both locations. The Commission of Fisheries has continued to give fullest support to the work of the laboratory under the commissionership of J. Brooks Mapp.THE LABORATORY'S /'eJeMch prog/'(11// aims to .find out biological information about the local commercial species that is needed to permit a more intelligent utili­zation of the fisheries. Through field and laboratory experiments practical methods are sought for improving conditions in the shellfish, the fin fish, and the blue crab fisheries. Thus far the oyster and its enemy the screwborer, the mussel, and the blue crab have been stressed. In addition, this program aims to develop gradually an improved system of fishery statistics as a basis for regulating fishing intensity in the interests of conservation. Regarding the oyster, the Commission of Fisheries needs more information on the productive characteristics of the dif. ferent oyster bottoms, the grounds that favor the attachment and survival of the young larval oysters and those best suited for good growt�. The oyster planters recognize the same need. The laboratory has made a start in this direction. During the past summer representative oyster areas were selected for regular examina­tion of the condition of the oysters, the abundance of larvae in the water, and the conditions most favorable for securing the best "strike" of young oysters. Clean shells ( culch) put down at random and without regard to the spawning condition of the brood stock yielded fewer than sixty-five young oysters per bushel of shells, whereas "culch" properly planted, when the numbers of larvae in the water · were known to be adequate, gave severalthousand "spat" (young oysters recentlyattached) to the bushel. This shows howmuch effort may be wasted and loss in­curred by oyster operations carried on without an understanding of local and seasonal conditions. The oyster grounds of Virginia are now producing annually around 3,000,000 bushels, a quantity which can be greatly I increased under proper management. The ·1,greatest number taken is from a little over 60,000 acres of private grounds, which I represents a small part of the total acreage I capable of growing high quality oysters. j' It is generally recognized that much of the state's best acreage is each year de- Icreasing in productivity or is being ren- \ dered useless for producing oysters. Facts clearly show the need for careful study of local oyster problems to assist the industry in much the same way as the demonstra­tion farm serves agriculture. In connec­tion with the oyster work the laboratory is investigating practical means of con­trolling the infestations of the oyster drill estimated to cause a loss to the state of �ore than $150,000 annually. Dur­ing the transplantation of oysters, drills (screwborers) or their eggs are not in­frequently carried to uninfected ground. In this \vay 'lhe pest has been widely spread. Steps are being taken to e_ncour­age trapping of drills and screening of oysters to rid the beds of this enemy. Throughout the summer, experiments · were conducted on the use of cheap toxicsubstances sufficiently concentrated to killthe eggs of the drill without harming theoyster to which they are attached. It waspossible under laboratory conditions tokill the eggs by submerging the oystersbearing them for one minute in a solutionof copper sulphate, one part in 500. Afterdemonstrating in the laboratory and in thefield on a small commercial scale the ef­fectiveness and the practicability of im­proved control measur-5, it is necessary toget their trial and adoption by the oyster.men.During the past two years, the ribbed [ 2]mussel, Volul!ci demissm, has come into prominence because of its value as a source of provitamin. In view of the im­tn d" e iate demand for more mussels and 'fHE FIN-FISH PROGRA:r,t OF THE LABORA­tory calls for close cooperation with the shad program of the U. S. Fish and Wildlife Service. During the last five years there has been a relatively low catch of shad in Chesapeake Bay and also a low price level. What steps are being taken to preserve this highly important fishery, to restore former production· and also price kvels? In general, two methods are employed aiming to restore the shad the almost complete lack of 11revious work on th · L' e1r 1JtOlogy, the laboratory is con-Cent f h _ra mg on those research problems _avmg direct bearing on mussel produc­tion. !he yield of blue crabs has been fairly llntform . v· . . ! . cl , • 111 1rg1111a l unng the past ec-,\Je, 1 he hard crab population that en­ters d · tl , Ba , tree Y into the fishery of the lowerY ts composed of some male crabs un-spa d Wne females ready to spawn or nearly so, and females that have spawned one or ml ore times. The relative abundance oft1esep 1. th . opu at1on groups vanes through lis� d'.ffere�t geog�aph_ical a.reas. To estab-crab sanctl!arres 111tel11gently and to;egulate the crab fishery in such a way as do a�sure a high, permanent level of pro­, nctron, more facts are needed concern­tg the composition of the crab popula-1011 Th . d k h · ere ts nee to now definitely ow many " " b . d t .. sponge era s are require O Se d" h it is be. t e Bay adequately. At present b elteved that more crab spawn should l c, s�ved, but it is not possible to state Jrec1s l h t' d, e Y ow much saving must be prac-ice or how this saving may best be ac­�Otnplished. During the past t�o sum-snoers the laboratory has investigate! with' tne s ( uccess ways of removing crab eggstrsponges) at the commercial hous\!S,ansp h t h. ortmg them to the laboratory, andt a c tng the larval crabs for distribution Ti . Water suited to their development. 11s artificial hatching of blue crab eggs \vas first of, accomplished during the summerfishery, namely, operation of hatcheries and regulation of the intensity of fishing. In usual hatchery practice, eggs are stripped from the, shad, hatched, grown to the fry stage, and then released to natural waters. At this stage many ,ue de­voured by enemies in the river waters where the young shad remain until fall. At present the Commission of Fisheries is conducting experiments to find a satis­factory, large-scale method for holding young shad in ponds and floats protected from predators during the summer months. When released in early fall, the young fish are about three inches in length, better able to survive and ready to start their seasonal migrations down the rivers to the sea. Thus far the results of these experiments are promising. Perhaps the most effective method for bringing back the shad is through intelli­gent regulation of the catches. There is evidence that the decline in Virginia's shad catch is due to too great intensity of fishing. This simply means catching Jish too soon, frequently brfore they 11ave reached maturity. R. A. Nesbit, federal fish expert, has assembled data showing the relative num­bers of shad of different ages in the Hud­son River and in the Chesapeake and sibl:94o. Last summer it was found pos­t �o hatch out over 3,000 eggs in ac ray eight by nine inches, and a 90 per , ent hatch was regularly obtained. Promis­��g _results for large-scale hatching were w tarned by suspending in open offshorew�ters individual "sponges" protected by North Carolina area. By reading the age of the shad ,.from . the scales, it is known that fish which .·· escape being caught. m�y go to sea and return to the rivers for spawning for as . · many as Jive successive years,- Thus there ire scr . . eenmg agamst possible enemies. [3} �ending the )\[gts Virginia's Mlty waters yield ,i livelihood for thousands, but intelligent conservation measures are c,1lled for if nature's bounty is to be maintained and increased [4] (5] Y. Kr. of ( '. are five year-classes and the fi sherman has in all five chances at the fi sh. In the Hud -son River 60 per cent of the total popul a-tion of shad are caught each year, and , j() per cent are allowed to spawn. In the more southern region, 90 per cent are caught and only 10 per cent are left to spawn . In either case it is estimated that 80 per cent of the shad that go to sea re-turn to the rivers to spawn the fo llow ing year. Thus, for every 1,000,000 fi sh in their first spawning year, there are in the Hudson 320,000 in their second year of spawning as compared with on ly 80,000 in Chesapeake Bay. Fish in their third, fomth , and fifth spawning years are even less abundant in Chesapeake Bay as com-pared with the numbers found in the Hudson. Acco rding to N esbit's find ings, in order to change the conditions in the Chesa-peake to those prevail ing in the Hudson, it would be necessa ry to use one-third less gea r for catching the fish. In its first year of operation such a scheme would entail catching actually one-third fewer fish . But as the years went by the num-bers of older fi sh would steadily increase. Because more fish were being allowed to spawn, more could thus return to the ocean, and, of these, 80 per cent ( accord-ing to Nesbit ) would come back to the rivers the fo llowing year and so contribute to the nuITtbers of the next year-class avail ab le for catch ing or spawn ing. Over a five-year period , for eve ry l ,000,000 fi sh in their first spawning year entenng the Bay, a total of 879,051 fi sh would be caught, including many large one., as compared with the 978,258 fi sh, with few large ones, which are being caught under existing condit ions." The 879,051 fish wou ld undoubtedly weigh more than the larger number caught as a result of pres-" ent fi shing intensity in Chesapeake Bay. This, :ts has been noted, would be with 'The fig ures used may have; an appearance of undue precision. T his is bc:cause they are wken from a tabulati on worked out mathe1rn1tio lly by Mr. N esbit on the bas is uf pe rcentages which are be lieved to correspond closely with the foctS, and have not been rounded to g ive the ,1ppcM· ancc of representative: r.1 th L·r than exact figure>-Fishing a pound net on Chesapeake Bcty [ 6] the use of one-third Jess gear, so that the cost_ of fishing in proportion to the weight of fish taken would be greatly decreased. The fishermen in Chesapeake Bay are now l · h If · used ( i.e. operating cost) has nearly doubled! In Chesapeake Bay, there are several declining fisheries that need analysis from the point of view of intensity of catch, fishing effort expended, and spawning reserve in much the same way as the cat-fish and shad fisheries are being investi-gated. Each fish has its own particular problems and requires individual treat-ment, but the principles are essentially the same. )t1ying a again as many nets as the3, 11c'e l h · ( , an extra cost w 1ch re1, resents a t t l J 0 a oss. In the Jong run, the excess gear. not only fails to catch any more fish llt it prevents a recovery of the fishery. PERHAPS THE MOST IMPORTANT NEED for determining the best way to rehabili-tate. a fishery is adequate statistical infor-mation. Such information is an essential tool to . . f 1 r. The Virginia Fisheries Laboratory, in cooperation with the Maryland and fed-eral investigative units, aims to develop an improved statistical system which will make possible more efficient and economi-cal management of the great fisheries which Chesapeake Bay is capable of sup-porting. 'f success u ushery management. he present statistical data consist mainly 0 ~ total production figures, and these pro-vide Iitt] I · e more t 1an a relative basis for compa . h ·' nng t e volumes of the several fisheri 1'1 es. . 1e total catch records provide scant inf . tl . ormation on the total supply in le w t 1 a er un ess the fishing effort ex-pend I · 1' h ec is also known. For a measure of t e fi h. ti is 111g effort, records are needed of 1e d ·1 . . a1 y deliveries of each boat the size a l , t nc type of boat and the amount and Ype of gear used the number of men ern J ' P oyed, the length of their em1Jloy-ment d h h , an t e.' number of hauls made with eac t I ob· ne eac 1 day in each location. The to Ject of getting these statistical data is of me~sure the yield in terms of a 1111it d fishing effort. It is this statistic that is c. epe_nded on to tell whether the supply of ilS<1 IS . , 0 • rna1nta111ing a fairly constant level, r 111cr · eas1n er or decrea 0 1'n1> t k' b ,,, ,· fish a mg a small but important local · ery a th t 's an example, it has been found a the J annu. al catch of catfish in the amts R· Ye · Iver area has, during the last five ars m · . of ' ainta1ned a fairly uniform level 193;round 600,000 pounds, valued in ab] <lat about $27,000. However, avail-e ata · rig seem to indicate that the aver-j1a; ;eight of the individual fish caught fr~111 :opped during the five-year period ont O bout one and one-half pounds to P tmd and that the amount of gear THE tec1ching progrc1m OF THE LABORA-tory includes college instruction, high school demonstration, and public exhibit aiming to acquaint a large part of the population with the conservation ne~ds of Virginia's marine resources. The 111-structional work is conducted in the de-partment of biology at the College of William and Mary. In additiori to the regular undergraduate instruction, courses in fishery biology stressing the aspects of the subject treated in this article are of-fered. There is, consequently, an oppor-tunity for the high school graduate. "'.ith fishery interests to receive college trammg in this branch of applied biology. The cur-riculum also includes courses of instruc- . tion for the graduate student who wishes to specialize further in the subject and to meet the requirements for the master of arts degree. In summer, courses in the conservation of aquatic resources and re-lated subjects are offered. Encouragement and assistance are given to high school teachers of Virginia to interest their stu-dents in the biology and conservati?n of local forms. · ' [ 7 J Demonstration material illustrating the biology of local marine forms is made available to high schools and pamphlets · are issued to give the students a better understanding of the materials presented .. The laboratory has made a motion picture film in color showing the anatomy and early life history stages of the oyster, crab, and mussel, and also methods employed by the industry in taking and handling I 8 I these: forms. A biological exhibit open to the public throughout the year is main· tained at the Yorktown laboratory. These several methods of disseminat· ing knowledge of the fisheries are serving a common aim. That purpose is to enable people to understand the conservatio_n problems of the fisheries and to apply this understanding toward the economic and social betterment of thtir communities. 

Conserving our salt-water fisheries: work of the Virginia Fisheries Laboratory

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Conserving our salt-water fisheries: work of the Virginia Fisheries Laboratory

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