State of Maryland

BOARD OF NATITRAL RESOURCES

DEPARTMENT OF RESEARCH AND EDUCATION

'I'ME LIFE HISTORY OF THE SILVERSIDE Menidia myteuzidia (Einnaeus)

FYIeLLIAM H. BAYLIFF, JR.

AUGUST, 1950

PUBLICATION NO. 90

CHESAPEAKE BIOLOGICAL LABORATORY

S010nlons Islandl Maryland

State of Marylacci

@omrr~isslone1-:i :

Franlilin D. Day, Chaii.$nair ........................................................................................ Centerviile

Ernest Pi" Cory ................................ College P a ~ k r- EarIe T. Rawkin~s ................ .. ............................................................................................................... 1 ovison

F r e d Tressel

E. R. Willie a l t i c~ore

State PT7eather Sc?-vic.e :

George N. Braneato, B. S., !TIeteoroioglst i n C h c r r g ~ ........................... ..,...... 3zltinlore

3 y r o c L. Ashbaagh, N. Ed., Educstio?z Assistcc?zt William H . Bayliff, Jr., B. A,, Fi.s.heq~ Iwvestigator. G. I?. Beaven, ?/I. A., Bioiogist I , Oyster I?rvestigutions Janies H . Carper~ter , 3, k., Clzevzist I I I Goit KT. Coker, M. A., Biologist 11, FisKeg-y In.cjesiyat.i'o~zs L. Eugene Cronin, PE. B.? Biologist T; G?.a5 I.nvestigut.i:o.i:s Thonzas S . DeLong, M. F., 8iolog*lst 111 (Forestrz;) Harold J. Eiser, Ph. ?it., Bio log is t XI1 (Aqziaibcj Vagn F. Flyper, B. S., Rioiogist I11 ( G a m e )

George B. Gray, B. S., Adrt~inistl-ative Assistant d l

I ia r ry A. Hensel, JT., d?zvestigatcr Galen H . Xcxfiz!d; G. S . , Ciologist 11, Fishcru Inuestigario!rs Earvey Mister., Captain, Fish CulCilrist, 112 Charge of Covzme~cia! Fish

Hatche~zes Fred W. Sieling, E. S., Ei~Zugist I I , Otjstei. Inv?sti,aaticns Leah Belie Sutton, Se?zioa+ SZenoyarap7ze.r R. V. Truitt, Ph. D., Bio!cgist F,. D. V a n Deusen, 11. S., Eiolcgist I , 111 Charge, Xataral Resoz~sce i;?ve:oto?-y Doris M, Woodburn, Sec;#.etal.y

THE LIFE HISTORY OF THE SILVERSIDE

INTRODUCTION

This papel is based on an attempt to assemble the existing knowledge of the silcerside, LIIenlclia menidla, and to contribute to what is known about the life histol) of this species. 4 Tast amount of work is needetl on tlie ecological relationships between the food fish and the forage fish. One of the most important forage fishes on the Atlantic Coast is the silverside. T o understand the inter-relationships between the food fish and the folage fish i t is necessary filst to unclcrstand the life histories of both. Fm this reason it is important that the life history of this species be studied.

For contribu~tions that made completion of this paper possible, appreciation is expressed to:

1. Dr. R. V. Truitt, director of the Chesapeake Biological Labora- tory, who suggested dle plobiem and cncouraged the study in addition to making funds and equipment available.

2. Mr. Coit M. Coker, thead of the Fisheries Division of the Chesa- peake Biological Laboratory, who supervised the work.

3. Mr. Romeo Mansueti, fisheries biologist of the Chesapeake Bio- logical Laboratory, urho made his field notes and specimens available.

4. R4iss Ann O'Rourk, of Tliestern Maryland College. who identified the parasites found on the fish collected.

5. 'ti'orkers at the Chesapeake Biological T,abbora,tor:, who aided in making collections and who gave much valuable advice.

MATERIALS AND METHODS

Fi,sh were collected in a number of ways. A hundred foot haul scine with ol~~e-quarter ill'ch bar mses.h, six foo't depth at the brails, and ten foot depth at the center was used wit11 either one or two Operators. L4 fifteen by three and a half foot seine with mesh fine enough to 21old eggs or th'c smallest fry was used by two operators. Part of the hun- dred fsoot seine was stretched across thee mouth omf the Green Holly Creek (described later) with the rest piled on shore. The'fifteen foot seine was then taken by two operators ab,out fifty yal-ds upstl-eanu and

worked down the narrow eleek, driving the fish zoward :he hundred foot seine. When thc fifteen f o o ~ seine had la-early reached the hiin- dred foot one, :he free end oL' the latter was quickly brought aro~~nc'i in such a rvay as to enclose t h e fish and i t was hauled irr the regular

Fscr dipnet coi!rctiolis, rvlzich were ~ a d c at nigh:, a crab net ti;velve in'ches in diametei- T,\-ith ozc-qua~ter inch bar mesh was usccl. A sr=,al! spot light bulb furnished light necessayy for the operation. Fish were not attracted ta :he light but were see.? s r~- in~rning by.

Salinities ar-c express~ed in parrs per thousand a l ~ d temperatures in centigrade degrees. Cullcciionj were p r s e r ~ ~ e d c ten percent lormalia a i d exalxined lorty-eig-ht or luolc hours a l e ppreservatio~~. Lengths ar? expi-'esse,d as tota! length in miilicne~rrr after preservation. Scaly5 were taken h-om pi-eserved specimens, rinsed i n iia:c::, and pressed to 6:-y between or'dinary microsccpe sIides. After drying. they 1ver.c piaced in scale envelopes for 'iacer euav.ination.

I , Sandy Poi~it, Solomons Is;ar;d, I\Pd.-drc~nE zbout rnlee feet in first hundlc-L sea lettuce present, saric) b o t t o x ~

2. Bay side o! 14ru.rri Point, Calvert GCIIII:~, XId.-Lropoff aboat four , ~

feet ir, first two huadreiL, eel grass scarce iiz semmg place b n ~ abxn6ant r'sl-iher nut and present on either i i ce , bottn~l; san'dy or shailo~t, dia~omaceoi~s ooze.

3. End of Chesapeake Biological Laboratory pier at Solonloss Island-$even hundred feet froin 5hol.c. d e p ~ h abotrt eig!lt Ice[, eel grass ab8usc',ar,t, !ice sandy hotto:n.

4. Mouth oi Green HsI?j Cieek, St. h1alr's Co7~c:j, %id-zi7~omt twenty feet wide acd two and n half leet deep re! ?lass a5.1~dant a r o u ~ ~ d ourhide of mouth bnt no r.c?etzttnos ;r creek paper, sand) bottom.

5. Msolly's Island, Solomons Harbo'x--dropoP a?orrt forla- feet iil firit h'undret?, r_o vegetation, sandy bottom.

6. Front of Chesapeake Biolugical Lab-%.- ,A ,t.l;ry, Solomons s i a n d , lXd.-L~-opoE 2:33ut OIIC COO: ill fi1.s; h;-~li'~?i.'eG; ~ e i i le';tl;ce absent

. , ear,y I:I jeason ~ s i l e n samplrs ~.vc'c takeu bu: .zljii;i;iz~il later oii;

. ~$

. h e sandy k-itarn: er ipci~d by l~e1.y :o~v ::u:s.

DESCRIPTION OF THE SPECIES

The specics .llenzd?a n ? ~ n z d l n has beell diviricd into two subspecies, Menidia menzdia menzdln (Linnaeus) and . l fenidio rn~nidzn notatu (A1itche;l) , the former bcirig the more southern type. KendaIl (1902) discuuscs the differeil~es sa)ing:

"Beginning with the St. Johns River, )If. dentex agrces most neai-'lp wit11 the dcs'cription of M. ~nenidin fllIe71irlin nzenidia ~ n e n i d i a ] ; north- ward the intergradation b,ecomes Inore and inore evident, reaching its height in the Chesapeake I-egion, whence noi-thxvard the chal-acters appl-oach typical ,If. :~ottria [hfe?zidir~ menidia nototo], apeeing per- fectly in nearly all specime~is north of Cape Cod.

"The differential cha~actels heretohie considered specific were the nioie backward situation of the fils1 do~sa l , fewer scales in longitudinal and cross series, and the deeper body of ;21. n?rtzztlia . . .

"11; Chcsapeake Bay thp differeiltial cllai actel s do not confoin~ to thc specific ieq~l i l -~ment , : thus ir~cbividuals with the backward position of the first doisal have the slencicr bodies and more numerous scales oE A I . notntn and lice 5ersa. With specimens from TZToocls Hole aglee- ing perfect]) wit11 L\/l. notntn, mixed forms as well ds peifcct &I. nlerlidin ale louncl, the majorit) being the ,If. me?/lclzn form.

" l ' he range of Menidin nzcnidicr, as given by Jordan and Eve.rmann in Fishes 01 Korth ant1 Middie America, is fro111 Ca.pc Hatteras to Florida. Curiously, the range of Af. notala, in the same work, is given south to Cape )fay, leaving an in~,e~-vening space of many miles-Cape hIay to Hatteras-seemingly urioccupied by either forni, but ~ ~ h i c h is inhabited by intergrading or mixed .forms o~f rIl. me~l idia and M. notntn . . .

"The intergradation, hou.e~;er, is not uniform. .4s has been said . . . specimens have been takcn in t,he Chesapeake which corilorm rcspec- tively to the descriptions of A I . nzenitlin and iM. il.~ofato; at tile same riirle others d o not ag1.e- with the description of &her, or rather par- rakc of the ,&a]-acterr of both fo1113s to such an extent that i t is irn- possible to say to which form it bclongs. Speciinens have been found at \fC;oods Hole, even, which were ess~ntially the M . ~rlenidia form. This is I~ai~dly an ideal intcrgratl;l.tion. rath.er such as might he expected iron1 thc interbreeding of two closely r-elatcd spccies and the occurrence of stragglers o f either of the .trzZo h r m s or their hybrid offsprirng nortll or south of the point of iritcrmingling."

Hiltlehrai~d and Schi-ocder (1927) state thst, “Tile extrelnes as n:ei: as the intermediates son~etirnes o'ccur in a single lot collected in one l'vczlity rcithiii a few hours." Elowe\-er, th is tasononlic diflerence. if any, shoulct not mean a difference in ihehabits of the fish. N o attempt was made to differentiate samples b> subspecies and literatul-c. on both fo'rnls has be-n used. Heliceforth the fis!~ in question i'~,ill be rcferred to as ltfeizidiu naeniditr or the silverside.

Fig. 1. Menidiu lr~enidir! : a11 inlnlature specimen, 56 mm. in lengrh (x 1031 .

7 lle following des~riptioll of ,Ilenzdla rnri7itl~u ii gi\cr, b \ I l ~ l d e - bi arid and S~111-o-cIer ([bid.) :

"Head, 4.15 to 4.7; depth, 4.3 ;o 6.93: 1). I11 to VII-I: 7 to 10 (usual foil-mula I V to 1'1-1, 8 ur 9) ; A. I. '30 to 26 ( u s ~ ~ a l formula I, 22 to 25) ; scales, 44 to 50 (!5 to 18 oblique rurb-s or, sides hetween 'zppcr angle of gill o'pening an'tl origin of spinou, dorsal). Uodp variable: lery slcnder LO mode1~itely de'ep and coinpressed; caudal pc~iluncle ratllcr long, its deptli 2.2 to 3 in head; head dcpl.essed above, narroti.er beLon,; snout modcratel:, lung, pointed, its length 2.7 to 3.75 in head; eye, 2.75 co 3.75; intcrorbital, 3.35 to 3.8; irlouth sinall; moderately obl iq~rr , nearly terminal, the l o w e jaw being slight!?. included: teeth in jaws pointe'd, in narrow banrls, wirh the outer wries somewhat enlal.ged; scales firm, with margins cntire, exterl'dinq soir~rrvhat on tllc base gf cau8dal but no: on the soft d'orszi and anal; urigir, oC spicous dorsal rather xariable, sonieiirnr~s about cquidiscarlt from tip O F snout and 'base of caudal, rnorc us'ually near.er the latter, he predorsal riistar,'ce 1.75 to 2 in lengt l~ to base of c ~ ~ u d a l ; second corsd situaieci ober middle n! anal base; caudal Gn moderatell- iorkccl; anal fin long, its base abou! an eye's 'diameter iongel- than head; ventral fills small, inae1-ted ecjui-

distant from tip of snout and end of anal base, or more usually some- what nearer the former; pectoral fills moderate, pointed, 1 to 1.3 in head.

Fig. 2. Silverside scales: A. Menidia ~nea id ia , Septenlber 10, 1949, 88 mm.; E. Mew~bras v a g m m , June 1, 1946, 104min.; C. Menidia menidia, July 21, 1950, 124mm.; D. ;l.lewidic: menidia, Septenlbcr 10, 1949, 90 nim. (nute doublc focus).

"Color greenish above; more or less silvery, with metallic luster in life hel,ow; sides with a bright sil~er):, ~vell-defin'e'd band, about half diametel- of eye, bounded above by a dark line; scales on upper. part of sides and hack rvith nulnerous bl.o~vnish dots; fins plain translucent; periton'e~uln black."

The largcst specimen found in this study was 140 mxn. or five and a half inches in length. There is 110 external difference between the

sexes, and the young after attaining t~<-e:ily mm. ar- pr~~ctically idcn- tical with the adults (see fig. 1) .

Th'e genllj 1Lfenidi.i may; i ~ e distinguished from the gcnus 3lembi-os , tile rough siiversidc, i11 1l12.t i t has cycloia scales ~.blli!e tile latter has strongly ctenoid scales (see fig. i'. A and B) . T h e sp-cies nzenidin :nay b'c di~tin~guished from Lhe species liei.yllinn, tile fr~sh.r.ratel- silccr- side, by the following table adapted fl-om figi~res giwn b y Kilclcbranri and Schroedcr (ibid.) and Kendaii ( u ! ~ . ( i t . ) :

Species Rozos of Scales in Laterni

S e ~ i e s Front U p p e ~ A,t~gie of

Gill Openiirg f c Ea,slr of C ~ ~ t t d c l Fi:'

AT. l j?enidir~ 39-50 .;If. beryliiitn 37-41

Rows of Scales So f t Axnl C o l o r of in Late?,al R ccgs i 'er i ta?zez~~~~

Series f.i-c,nz Black U p p e ~ Ang lo o j

Gill O ~ e t ~ i n ~ g t o Origin. of

Fivst Dorsal Fit6 1.5-i8 26-29 "Silvery, m i t t i2-14 14-20 or withoi~t

dasky cune- tuations!'

Differ8elltiation of t i l t t1t.o species by peritoncum ~ o l o r has proved in practice to be ar, unreliable method. J fc l z id ia brr-yllirro r-areiy attaini a It-ngth of o x r tiller and a half inches.

Afznidio ~neniilicc has been cal led capelin. smelt, >,oun? smcii. glecn smelt, saricl smel:, sardine, anchovy, sILin'er, smal! fry, 11-ier, brit; spear- ing! sperling. whitebait? a d sil~.el-ide. T h e first sercn names arise fro111 confusior. with other species. I11 N c n Ycrk City, ~vllo!esalerj and retailers of silversides call i \ l ~ r~ id iu tnerjidiu "spearing" and !!Menidin bei-jll ina "~vhitebnit," difieientiating the species by tile greater si7e of the lo'rmer. Wo\v8ever, 'u) far the :nost cornlnon ilalrle for tlie genus , l fenidiu is "si!vcrside."

Silverbidcs ,ha\-e I~eer, tol.~nd in t!-:e a~umachs nf biuefisi:; Pu~tri i to inz~s s i i l t a i ~ i x , striped bass, Rocrzrs sccxatalis. g r a y squeteague, Cy!~o.:clon 7-egmlis, Slack -sea bass, C e ~ j , t ~ . o l ~ ~ . i : i e ~ sti-ii:tzl.r: northern scup, Sicrz~to~sz: ls c l ~ , y s o p s , Atlantic msckcrel, S~.unzDer sco?n(;~rts , Arinntic bo~lito, Snl-do s n ~ d a , cunner, Tnzitogolnbi~cis adspe;-.<us. silver hake. ~?fer-licctilcs hi- linen?.i.~, Atlantic coCi Gudr~s n i o r i i ~ i n , Atlantic tolxcori, 1\4icr-3gndr!s iontrnd, and squii-I-ci hake, Crolrhyi.is clz~rss (Bigclo~\- arid TVeish, 1924) . :\'lerriman (1941) studied the fooc, habits of the striped hass allti co1-i- c l d e d that, "The incst conlmon lorm of £006 in C0~11ertic~i.t v x t c i - s

is the shixer, or silversides (1Menidia fner~idia natata) . This is a species whi'ch spawns ill the spring (Hilclebrand, 1922), and the young of each year stay so close to shore and are of such small size that they d o not become available to the st]-iped bass as food until August. At this time they .reach 2 cm. in length and often stray farth'er offshore. . . . Stonlach content analysis o,f striped bass 30-50 cm. long . . . in 193G an,d 1957 shorwd that adult Menidirc and the conllnon prawn (Petlae- moneles vulgaris) formet1 the main h o d from April to August, but t.11at in August and September the bass fcd on juvenile ~Wenirlia lo a large exbcnt. Shortly after this changc irm diet in 1936 there was a decided increase in the growth rate of the two-year-ol'd striped bass . . . whi'ch, despite tbe drop in MiaLer temperature . . . was 91-eat,est i n O,cto,ber. T h e presence of rvhat was apparently an unusually great number of j n ~ e n i l e menhaden (Brevoortia tyronnus) in 1936 may also have played a part in this irbcreascd growth rate, for from August o n striped bass commonly fed heavily on this species during this year. IImowever, juvenile menhaden tvcrc not as abundant in 1937 in this area, yet the growth rate 01 striped bass in September and October continue'd much as it had throughout the summer in spite of thc drop in temperature. . . . It therefore appears that the increased food s.upply of striped bass resulting from availability of juvenile Mcnidin after fth'e middle o'f August may be coaelated with the lnaintenance or in.crease of the growth ra te in the early fall when the water tem- perat'ure falls rapidly, and when th,e normal expectation ~vo'uld be that the growth rate 1,vould slmow down." 'l'he silversi.de, being restricted to the shore zone more than anchovy, A~lchoviella, the menhaden, or the Atlan.tic 'l~erring, Clupen harengus, is presumably a less iin- portant ,forage fish than these but still valuable in this role.

It is reported that in 1946, 126,300 pounds of silversides were caught commercially in New York State (Anderson and Power, 1930) . Accord- ing to 1Yillia11l H. Dnmont, Acting Chief, Branch of Commercial Fisheri'es. U. S. Fish and IL'ildlife Service, in an unpublished letter, tthese silversides arc Menidia n?enidin, knorvn to ~hol~esa le r s and re- taile1-s as spearing. Tlhe); are sold in S e w York City restaurants, par- ticularly ,those patronized by the Latin races. T h e fish sold as whitebait in New York City are chiefip Menidia bcryllina but may contain young of other species, partic~llarly Alcnidi~c n~en id iu . Anderson and Po'wer (ibid.) report that 32,000 p m n d s 01 whitebait were landed in New

Yurk Statc in 1946. Silvenides are uscd to some extent as bait but are inferior because they die too quickly for live bait and so'ften too

soon on a hook (lier~dal!, op . ci t . ) . 011 Prince Ed-rra.1-d Island they are sometimes canned or used for fox fwd (McKenzie and Day, 1949), and in so'rrie locaiities they are used ;o hair eel pots.

Reports on :he palatability of <?I\-ersides have bee11 highly f'a;;orab:e and i t is q u i ~ e possib!'e. that they could sp~ifig quickly to popularity as food for h i ~ m a n c o u s ~ ~ m p t i o ~ ~ and he Ilea~i!)- fished by man. h large scale rell?v\:al of this natul-c x\rould not necessarily meall depleiion of this species. Usraalil- an opticlxm fiiiling pressure can be established for a species where ari a r n ~ l c 3:-uod stock is left. Even if dcpletivr: ~i lonld result i t cannot he saic: to be ha1nlC~11 u:?tii tile cco:qical rela- tiorlshi'ps ol L ~ O si!i;erside with othel forage fish; with the young of corn- :llc:-cialEy important species, a116 i'vitli its prcdatar-s is thcrou:;.hIy urlde~s.l.stond.

SPA%'NING, EMBRYOLOGY, AND LARVAL DEVEEOPBqEPJT

SiEvorsidrs hatcheil in :he spring iri the Ciresapeake Bay reach their adult size, usually a little ox-el- 100 mm.: by Decernber of the same year. T i ~ c iemales aveiage slig1":ltly largcr than tke males. Thc goliads develop sluxvly but 5:eadil)- throughout rhe wir.ter and up until spawn- ing takes placr. T i m e of spaw:lliiig varies T$-irh the latitude, the peak ili Chesapeake Ba)- occur~ ing i?. May. In N o r ~ l ~ Ca'rolina ripe fish ai-r found as early as March anci as iatc as r i ~ g u r t (Miid'ebrand, 1922) with t!ic peak occurring i;i *%pril a d >lay. ill S e w Englarrc!, the peak occurs in !ate june bxt ,pz-~~-ning is knox~-n co have o.ccurl-ecl as early as &la) (Sigeiow and l\'els!~, 3) . cif.) . l i l t data in 'T'able I snow :he de\-elopment of the gonads, the :i!rle of spawning, and ihe size of the 5sh a! sparvnil:g time of five samples of sil\:ersidc5 taken in CIlesapeakr Bay, These data ir?'dicate that:

i . T h e spaivlli~lg peak occurs in May.

2. T'he1.e is a positive cot-relation heriveen gre2ter size aild earlier ;naturi ty.

3. Females at ~ n a t u r i ~ y a;-? Pargcr than :lla!e>. . .

4. Thougil tilere x a ) - b- g x a t val:ailoE i? individual collections, 11:i:rel-ica!!\: :tie sexes in : ipt: ii,h a:-e appl-oximaie!y equal.

ESildebra~ld ( o p cit.) an& Hiidebrzcd and Schroedcr ( c p . cit.) suggest t!la~ silverhides spawn lllove tiian occe during a seasoil, basirig

their assumption 047. the long period oi time in whch ripe fish are found and the presence of diEerent sizes of eggs in the gol?ads at one rime, That pl~enau,irmenon was observed in this study. Ro.cve\-er, all eggs examinNed were opaque except those of the iargest size which were virtually, transparent. Since snaall isanslncent eggs wrrc seen in the Bate fall, i t is to be implied that these smaller opaque eggs seen in the sprhgtirne were either d a d 01- arrested ones that svouid nor de- velo'p further. No cane 5as reported finding ripe fish in l uge nammbers at any time oth'er than spri~lg and early summer and no larvae have been reported found after th'e eighth of Aug.casi, In fact, when t,he spawning peak was passed only a few of the fish of the spawning Lass .were fourid in this study, the Bast being fo-iln'd OE. July 21. Thus i t is almost certain that this species spawns only once, at: least ir. Chesa- peake Bay. Figure 3 does suggest, however, that :here m a y h,p two spawning beats a few .weeks apar; by ~ w o po'pulations of fish. Gunter (1945) s!l'owec? that. Me.vzidia be~yiirna pereins~ulae, a Gulf Coast species co'nltparable 1.0. Menldia mereidia, spawns twice a season, once in the spring and on,oe in the Pate summer, It may be t h a t an inrcli.riidnai fish in chis am-ea spawn twice during a season, or that eacn spawning beat is ac,cos?aplishe~d by fish i>f a different age class.

T ~ h e fish conp-egate %n shallow water cl'ose to shore, when spawning, and ,deposir their eggs and lnile where in r o ~ y strands the eggs cllir,g to vegetation and to each ocher. Fowler (1918) gives :he fo!.lo\iiing descri,ptio,n of the spawning act: "'May 12 we found bunches o f spawn in the meado~v grass, j'ust below high tide, along [he shor'es of Magothy Bay at Long Point Island [Northharnpton Cou~lry, Vir. giniaj. Also a mum be.^ of d'ea'd fish was found in the trash an? debris w ~ s 1 a e d above the tide-mark. These had all spawned several days beforet as they were a61 q u i t e fresh. Mr. George Skidmore; wIm re- porte'd seeing a large sschs'ol spawning in this locality on May I, was attra'ctcd by the gfeat -num.b.es of fish c~ngre~gated, whi'ch N7er.e appar- eastPy to the r~umber o,f several thoasarrd. individuals; all c~llie'ct~ed ai: high waxer over the grass. At khis time the wat,er was but severaI iilck~es deep : and the fish occupie'd an area of a hundred oi- more s p a r e feet. The waier i o ~ a still. greater area was all white avhh the expelled milt 0.i' the males, so chat i t had a cor,s'pica;ous milky appeaanoe. Ail the ffisfi were ~ r e a t l y agliated, tossing and tum,bling about. As :he tide wenit down they ail noved OR-shore with it, and the eggs were left at:ach'e'd oi- scre'ened by the grass orr he dampened shc~re to await the reeurli of high water, Doubtless aiae ' seater part fi'f these eggs perish

ii;. d1.e devo~~recl by crabs, 5i;.:lj, ptc." Burr-nus ( ? f j S S ) 2nd HiIdrbrand. (n?. rat.) also =enti02 eggs being :eft a:: silo:.:: by fiFe receding tide, Ryiier (4853j sugges7:ed ::laat the si!ve-side is a :~~c:il::laI spawmsy bjjr no ocher ~,bse?-k-,n:- cc'nfil-:ns this ehcory. Repeated ieai-ch,es were mace, in :!;is ,tud), on the b ~ a c k e s cf a creek where !z::ge nu:~iSers of ripe

.> .~ siive:-s:c.-s :xTe-e fou3.I bur no spaxv:~izg iish or eggs i ~er t . seen. .? f i n e nmeshe'd seine was draggec t-5rrix'gh the ee! gr2ss or. ser:eral spring

~ * seming :rips wf.5out findin.- eizlner eggs or :al:vae; a:~?. w81znkrori tows cl,=sc to _ahore also fzil'ed to pro'duce larvze or. eggs. 'jns::ccessful seal-,cSes in!- eggs a ~ ~ d spawning fisk xccrc rnade along a. beach where, iatei-, lar8ge r-ui;l'se~s of the ~ ~ ~ l ; r ! ~ , ~ 5sh Ic:r,e f~ ' a ; ; d ,

Dnr.ing the pe-iod when ~-:pe fi's'h wcrc ioucd, eg,gs were stripped inte s11aPic'w dishes c ~ n r a i z i z g a i i ~ t l e sez water: milt was srripped o7.w- :h.ern, acc" momre wrter- was addi-2. ZzThe:~ th!ese eggs :4:eh-r brc~mght to the lab~~laiui-); noneof tkcr hatched or s3o~~:ed evicler~ces of hzving be'en fertilizei!. Ri?e ma15 an? fez.ale 5sh wcrc ?!aced in 12 ya?!lon - a~cxaria 5i!cd with sea .it7ater in hope tha t t'le:; would spawn. Eggs were exitded soon af:er~vard by scmr- of the icinzles hut this was

*" ~ probably more i r i the nature oi a miscarriage ?.l;ar, s ~ a w n i n g , ,b'snee runl:ing sa l t iirE'ier w a s zoi: avzilable r3.e Ssl; die'& aiter 2 Ee.crr days.

A ri'pe ielzale ~ o n t a i z s aboult 3@G mrtr;re eggs and :nar,y sli~ztl ie~ -. seemingly dezd. o'r a-rested ggs . I h'e zggs are slightly more than z

. 7 . .

mlilrficter in iliamete:- a;zd splierical ic s i ~ a ~ e . T h e y aye yeliowis;: 111 ccloi., se~i- t l .~~ns ,pas-e~~!i , and hzavie'r rilzn sea-~vate:. Tkere is a:- :ac;lcd. zi- one pssle a ri~:lrlLer c! gelztinox t:x.eac!s aboiit five rimes

7 ~ . . . as 1or.g 2 3 the di2met,cr i:?e e m s Tj?ese :breads aye ?:uo:;.c:~- 1:; t f ielx . .," ija

ac:.,mcy to strcrc" and cs.ntract, very mugh and czpabye of a 'd l rer iq . . . ~

:,,rltil g r x : : , ~ n ~ ~ i l v 1.3 $ ~ . : ~ 3 ; 0 ~ : ~oj; c;k,ecl the:. er_ccn?~lrel-, Inc!~~&:rg

~ : : ~ c ~ eggs. 7 - h ~ funcf:c:l of t.l~::si. <nreaCj a;jpc.a:s tc L:. :(: cling to +.e T.!ccFr,~-

. . , ,L.:hi=; ans ;s:evCn: .;hi. -gqj 5~121 :ias:::ng :sils:e 5: ::es:ifi.z

on hs;:.;.,~ ;<lle;-e sz!.r:jLvmi !-har?.cei z:? p:-ohsb:!; :cx,.e:- S,=X:~T?.~ oi:

g!cj/)u?cs 0f ~ : ~ r y i n g sizes are Sound :n ea.clm egg

.. . - h-0 j:udy ol :he ec;by!;~.!ogy 0: :hc saix.ersrac x.;~ u:L2.e:-~skc.n r,i?e

, . couLrse c,f !:hi,! work bu t the scblec; nas nee:L :.,,e:! ccc.ered by R-!;fiiz and Ra.dci'Se ('zSi7j ; Hilciebrand (op. tit.) : a::d Ciari a:;& Xo\ll:'or; (1949) ~

-* 1;l.e inc~:Sai:i~r: p f ~ i c ~ d i~ a b o ~ t ten d a y s at rrorl?~:zl t::u:peracures

. - and t5e new:? .hatched 1.1-i-ae a:-e aboct fivr rxr;; rz kc , -9 . "I'hesc

la] \.ae h a ~ e lost I ii tually all theil yolk sac but still 11ar e a continuous vertical fin-told (Hildcbrand, op. cit.) . By the time the l a r ~ a e ha1.e reached twelve to fifteen inm., the fin-fold is lust and it resembles the adult (Bigelo~v and TVelsh, op. cit.) except that the lateral band is not \\ell differentiated (Kuntz and RadcliEe, op. c ~ t . ) . Larvae, 4.4 to 9.1 min. in length, were taken b~ Pelltnutter (1938) from Ma) 12 to August 8 in plankton tows off Long Island, New York.

LIFE CYCLE AND HABITS

After spawning har taken placc in the spring, young sil\ersidcs can be found along the shores of salt and blackish water bodies thlough- out the ~ummei . They trax el in schools and often go above tile low water ma1 k. Because of thejl extended spawning pel iod, there is great laliation in size through most of the summei. Slze distribu- tional hlstogian~s (fig. 3) seem to indicate that more than one popu- lation exists as a result oT mole than one spawning beat. Blocks I-1- and 16 each ma! shosv t-wo populations, the )ounger being on the left. In block 17, the younger popuIaeion has cwnle into piedominance while in 18, 19, and 20 the older one p~edonlinates. As indicated in table 2, houever, 14 and 1'7 weie collected with a 13 foot fine meshed seine in bhalloxl %vatel while 16. 18, 19, and 29 were caught ~vi th a 100 foot, one-qualter inch bar seine in water up to four feet deep. T h e large seine, because of ~ t s greater length and because it c o ~ ezed deeper watel, was better able to get larger fish, whiIe its coarse me5h undoubt-edly caused it to lose many of the small sil\~eisides. Convelseiv the silialler seine, because ot its lesser length and becauqe it covered onl) shallo~vcr %vatel did not collect m d n ~ lalger fish, while its fine inesh inade it efficient in capturing smalla ones. Hence samples obtained with the laigc seine are biased in the dilection of greater lengths, while those obtained with the smalle-t seine ale biased in the opposite diiection. The srnaIIer seine was used earliei in the season and the larger one late1 because the former rvaa p~obabl) less biased when the fish ~cc l c smallel and !atel the larger seine was probably capable of getting a better sarr~ple. T h e data ale far too inadequate to establish the exiatcnce of pol~ulations but do suggest their plesence. XVhethel these populations, i f an!, pel5i,t 01- ale erased by c~n>pensatoi-y growth is unkno~vn-1949 yea- class si/e distributional histoglams (fig. 3, hlockb 1 to 11) gix e no indication of mole than one population. T h e erratic lengt-11 distributional cuir es obtained by '1VarTel and Merrirnan (!944) sceili LO indicate rnorc than one population. T o establish the existence

60

4 0

20

m

60 W

5 - 40

C3

LJ

a 20

Y,

6 0 be

0

4 0

IL

brl 20

m

2

3 60

Z

40

2 0

0 B 50 100 150 50 100 150

J O T 4 L L E N G T H

Fig. 34, Length frequeacles In mm. of dierzzdia v ~ e n i d i a collec~ed at Solo- Inoris. The total peiioci here 1s from Augcst 10, 1949 t o Xarch 24, 1950, and ~ a c h numbered block s u n s ap several collecriov% aq

~naicated :n Table 2.

0 50 100 150 50 100 150

T O T A L L E N G T H

Fig. 3B. Length frequencies in mm. of A%Ienzdia merzidiu collected at Sola- mons. The total period k.ere is from ApriY 6, 1950 to P ~ l y 13, 1950, and each numbered block sunis up several collections as indicated in Tahle 2.

or non-cxistencc oT popularionj and spawning beats will require many .iargc, cal-t.E111!y collccteil samples and extensi1.e S'ata on spawning.

T O T h L L E N G T H

Fix. SC. Length f:.eyue:~cies ir 111111. of 31 enidis 17~e)ridirr collected at Sdo- mans. The totlxl period '?.ere is f rom July 17, 19.50 to August 4, 1950, and each nuinhered block SUJ-ns up severa1 collecti3ns as iridicated in Table 2.

Cko\vt.ll of sii~rj-5ides in Chesapeake Bay is rapid th?o-ugi~uur the snlnmer .so that they Irave reac!ze< adult bize by winter (see fig, 4 ) . Vcrrilu'm (op ci t . ) saiirpiecl siiversideb from July 17 :o Srplerriber 2, 1937 in Corriircticut an? got a ~ : r m t h rate f a r siouyer than tliat foun:l i n C!lesapeake Ba), suggesiirig ilia,. Cennecticui 5ilversiS.e~ rake TWO'

year, TO rnature. IT h i s is the case, t!len i t is concei\able that hiai~le ji!x~cr.side> require throe yrar-r to mature arid Florlda silvelsitles might have habits si~riiiar to those oL' i i ~ p Gulf Coast lol.n~, .VIenzc/in be.r)1llina pt-nin~ztlac (sec 'page ! I ) . B i g c i o ~ ~ ~ an:I Weish (0) . tit.) ; in reporti~ig o n 5 s h e of the Cuif of Maine sa!.: "P~obabl>- :he silve~sirle attains 11ra~urity a t on? year r;f age" and Tracy (19i0') is of this opi:iion i3 ~ c g s r i . to Rnode Is!a::c! s~i~.ersi i ies.

, Is the wi te l tempcratur r d~opoei! rn 11;e fall. s~lxe: d e i bet amc scalcer in heirling h a i r . - ~ h ~ l t . ,ilidr\-~nter haul5 cangh: n o fish st all

en a n d Merrixan ( o p s i t . ) were miable to catch (see table 2) . Wa-l silversides b'y seinilng in midwinter. T h e method em8ployed in tihis stad? for getting fisl: in the winter was that of dipping Prom tiie end ol a seven-hundred-foot pier o w r eight tert of wake?- with a dipnet and Tight at night. This merhod was productive of srrmaU numbers of siive'rsi'des ~firoughorrt the w i n t a . This cvidence wnuld ee~nd to incli- cate either thar. rrlost of them have migrated ro deeper waters DT died by wintertime. Several authors hold that silvcrsides are found alorig thc shores ~ h i - o u g h o ~ ~ ~ . thc winter. "Silversides aTe probably resident thrnugilorit the year r:7herecer faunci," (Rigel'ors and 'T!'e!sh, i b d . ) "It is rhe orb17 fish whic'h accu1.a in large numbers in the s!la!low waters, t~hrclvgh;ho;a.~ ihe winter, l a r ~ schou!s may be seen alo'ng ~ l l e shores of Pivers Island [Eorth Caroli~laJ duriug the coldest days, when pra'ctically all other fishes have migrated to deeper water or to a rVarl-ner Iatitude." (Hiidebl.ar-ad, op. r i t . ) "Br pmbabiy remains ncar shore ciurir?g mosi of the winter, hut part of t h e m at lealst retire to deepcr wa:ter. during i1-1e perioc! of low t.:mperatures. . . . S'il~;essides were caught in many beam-li.arvi hauis during these w-inte8r months, but the aggrrgatc catch was sil srirall in corngal-ison with .tile known a,bun'danr-e of tlie hsh along shaft-e during most of the year that i t is doubtful if the deeper waters of the Say can be considered a. t\~interirig gruunci." (Hildebsand and Schroeder: op. r i t .) . i t is poasi,S!e tii'at. >he reason Ilildebrand a n d S'cbroeder found so few fish irn the winter was 11a.t because most of them rv8ere close to shore b:rt became most of them ha'd died by winm-time. The nuinbcr of fish found in the course of this ini:estigatlon in the spring Mias f a r less than he n~irnber found the preceding fall. Bezn j1903) says, "Tile coinmoe

silversides . . . lives in Gravesend Ra-)i (New York) alrncsr ail rbc year, lsiherriating in spring Iloles i n winter." LITll.~n Grecn Holly Greek waq sampled on M\/ial-,ch 2.1, 1959 about 500 iish were h~lni";.

These fish illa)i have spent :he cvinter these-nu pi.i.vious samp!ing was

done, It is doubtful that the tr'ernei?doun numbers of silversides found in the silmlrrrr 2nd; fall could spend the cvincer in this and sirnilxr creeks witho~lt being rioticed, hilr rvith a henvy nlortaliry in the fall it is c.0'1-~ceivable that this might happen. 'Tile c;uestion of silrersiclei' winter- ing grounds is stjl! an o;,en one..

Growth. of sA!\ ersidcs stops d r r ~ ~ n g elle vrintcl (see hgs .'$ and 41 In1 thc spring of 1950, ?drge numbers of ripe fish \yere found in f h r mouth GI Grcci; Holij $:reek SQnings 3: that tame alor~g places

rchere they arc fouild during the sulnmer failed to produce fish and it is pussi,blc that this creek and silnilar lo'caliti'es are favorite hazlnts of I-ipe silvcrsides. Felt, silversides of the 1949 year class were fuiln'd after the): had spaxvned in the spring of 1930. Fo~vler (op.cit.) mentions s?lvc~si\des dying after spatvning (see pages 11,12) . 'The ]as': silverside of thr 1949 year clash was found on July 21, 1950. Scales showcct a rvintci- and,'o~ spawning ring follo~ved by growth (set: fig. 2C) . If a silverside \\;ere to livc and grow at the rate shown through its second summ'el. and fall in Chesapeake Bay it woul'd attain a length 02 eight inches or more. No fish of such sizes have been observed in this st.udy or repar'ted by othrrs, strongly indi'catiug that silversides meel death in one tvay or other s'oon after spa\,\li~ing.

O L ~ L of 880 fish whose gonads were exalllined, 356 were males and

524 were females. In 19-19, from eal.1~ August until the end of December, 145 males and 325 females were found, ~,i,ilile in 1950 the same gear class showed a ratio that was nearly equal, 199 rilales to

214 females. bt is signif,cant that thc ratio is so nearly equal near the spawning time alter being- so far off rvh'en thr fish were yaungel. 111 i~ldividual coPlectior~s thc ratios varier1 highly, for instance: .4ugust 16, 31 ~xales arlcl $9 fcmaies; -4pril 6, 78 males and 24 females; April 24, 41 males and 39 felnales; Ma): 1 4 , 1 male and 29 Lennales.

T,\.'arfet and hlerl-iman (op . cl t . ) found t,hat the silvel.,sicle population 01 an area in Coilnccticnt had a tendency to iacr-ease slol~i~ly anrl steadily irl numbers for one to r~vo months in rile s:mnlrncr and h e n to show a suddcn dropoff follow~d by- a similal. building-up procejs and arlo~ller dropoff. I ' h i s pattern was erased as the fish disanpeal-ed from r!le arca with rh,e aclve~lt of cold weather,

_\frnidia ?t~e?zidiid ranges f:-om Nova Scotia to Florida in salt and brackish waters. The species intcrgrad,es ~vitPl Mell idia Oeiyllirzcc in waters that are nearly fresh. Large numbers O F i\S~rl.iclia belplliria were f m n d in front of the Chesapeake Biological Laboratory (station 6) in hlarch, April, and &fay. Alcn id ia nzrnidia i s the predominant species of silversi'des here In the summer when they are s111aPl but during those montlls ~vlien onl!: large ilferze'di~c ? ~ z e n , i d i ~ exist 'the i l l cn id ia be?-yll'ina are ablc to rake over. IJsually at salinities ovcr ten AZen,idia wlenrdia

predominates (Manstleti, 1950) .

FOOD HABITS

Kradall (op. tic.) examined 367 siiverjicies srr)lnachs at frequent inte:-va!s fi-om April 1 to December 2 i , 1900, in a nunlber of ioca!itie.? in the vicinity ol kVoods Hole, Massachusetts. He d o e not specify .hat these fish weye ,?fenidin nze?lidia hut lrom the accompanying length measui-eilienrs and the places of capture there is little question but that the!- were of this species.

Through the mon'ths of April, May, and June ro'pepods werc found in most o l :hese stomachs and usually iriade .up most or all of the toia; vo'lunle of food in (the individual stoinachs, i\.lyis was found fr-e- quently in April and early &lay ;chile fish eggs (mostly, if not all, their u.\\-n) we;.e found in late June. Empty stomachs rvere Tare d u ~ i n g these months. During tlie rnonths of July through November, food was murh more varicd and few strong trends were ~?otecl, Lnpepods were rare during thcsc morlths while empty stomachs were illore conlrnon. Prawi~s wme failly com'mon in late September and in Orto- ber and November. In late September and early October a number oE ins~c t s of the ordcrs D i p t e ~ u alld Hynienoptera were found. Decem- ber sho~.iie'd only cmFty stomachs on the two dates sampled.

Other foods found by Kendall were diatoms and unidentified algae. annelids and unide~ltified xvnrms a squid, amphipods, crabs, a clado- ceran and u n i d e ~ ~ ~ i f i e d crustaceans, an rrniclerrtilied insect, sniall fish, and ooze.

Thesc fish were taken froin a number 01 localities hut no change of food habits ill1 di8erent environme~~ts is eviclenr. T h e lengths of the fib rvci-e given, ranging from less than three to over five inches. Average lengrh and length rangc wei-e about the same througl~out ~ i l c sarnpliug period eliminating tllc poaiibilitl of the food changeovel- being due to a change in the size o l tlie fish. ? herefore thc c'hange- over from copepods is probably due LO a change in the availabilit) :,f food, April, Ma)., and June sccn: to be, on the basis of low incidence

of enlpt); stomachs, the moriths of best feedizg lor the :~lont~lis salnplcd.

These figures cover only a nine month sat-ilple in soutlieai Nassa-

chusei~s. VlTilether the feeding pattern is sirr,ilar ex-ery ?ear in tiiat

locality and whether i t is siillilar to those of other !ocalities is unknowr..

T h e stornaclis of a number of silversides taken in Junp vhich axci-

aged about 3.5 nim. in !en@ w e i r examineti at the Chcsapeake Bio-

logical Laborator!. 'Pliese stolnaclls contailled irlostly sand wit11 a few diatoms and molluscs.

Feeding can be adjusted to changing conditions. For instance, Kerrtlall fou1n.d diatoms were eaten on t11,ree occasions only and the i,ncidences on .th,esc occasions were l~i'gh. Probably the diatoms vxre available a t other tiines but not eaten by adult fish excepi wll~,en little o ~ l l e r food TI-as asaila'ble. I n a sample of 30 adult fish takcil in this study on May I I , 1950, every fis11 was found to be gorged ~ , i , i~ l l annelid worms. These probabl~r became available suddecly in large ql~an~ti~ieu and the fish took advantage of :he situation. It is evident from rlxe bods taker1 in that the silvcrside i j both a top and bo t to~n leedcr.

PREDATORS

As m a y be seen by the figure on page nine, man is o.nly a mirim- predator of the silversirle. Beside the fish mentiorled or? page eight, the needlefish, Tylnszi1-~is,, sea robiri, Pri?r'onot~~s, the sculpins. family Cottidire, toadfish, O$slrnus tau, ai~r l ~vinclo~vpan,e, Lopl~a.s~ttcx, aquosa are known to fe'ed on silverjidcs (Bigelo~v and T,l'elsh, op. cit.) . How- ever, i t ma); safely be said that any fish that lives asscrciated with the silverside and. feeds on small fish uses he silverside as fooc?. l3ecans.e of the to'p-swimming habits of the silverside, gulls, terns, kingfishers, and other birds prey upon i t .

PARASITES

No spcrific study of the para~ites ot the s i l~a-s ide was made hu t the following were obselae~? i n the cour>e nf this \vorEr:

Glasb Tienzatot ln , one uniden~ifiecl species

Class Nzrz/dzanet~ Piscicola, tn7o unidelltificd species

S u ~ n ~ i e r , Bsburl?, and Cole (1913) give the folln~uing ;>a.!-asire~ icu:ic! 011 silversides in thc J-icinit); of Woods Kol,e, Masiacilusetts.

Distomuln sp. Gaste?-stonazrrrr. sp.

Cldsq Cestoda R>hnrobothriz~ni bzclbifer Kyhnchobotl~riz~rn z n ~ p a ~ i s p t n e

Class _Ven~ntoda Fllo~-ici sp.

3lart1n (1939) s:a~ed that A I e n l d ~ n nrenzdza pases oil the Trematode, Shephnnosfomum tenzre, to the stliped bass. i t is probable that the silvcrside iq an internlediate host for other palasites that ale found in rhe food fishes.

SUMMARY

1. T h e sil\er5ide, Menidia ~rzen fd fn , is a small fish of the family AtJ?e).~nrdiie, 01-der Mi~gilzfo? rncs.

2, Though it finds 11nlited use as bait and h o d f ~ r human and animal cnssunlption, the PI-inciple value of the silverside is that of a forzge fish.

8. Spawning takes piace in shalloh water in the spring and eaily s u m m e over a:1 extended period of rime.

4. T!le ~ilverside in Cllesapeake Bay live5 only one !ear arid dies soon aftcr spawning.

5. Thc sex lat io in young fish in the11 hrst surnnler is about 2 tu 1 In fasol of femdles. During spalining season, :lovt.ve~-, the ;atio is a'Jor?t equal.

6. It is a marine and bra~kisn ttater hsh of the Arlantic Coast of the United States ant1 Canada. It liite~.grades rb i th ,l/lerzidzn beryllir~o as the water grotvs f~esher .

7 . It i\ lairly adaptable ill it? food habits, Cecdlng mainly upon algae, i a l ~ a c , and imall an~rnals.

A The silxerside 19 p e \ e d upon extensilelv by other fi?h, i n~ lud i zg rrlany of the cornlllel ~ i a l l ) important specie,, and b\ birds.

This bibllog-laphy replesents, so fa1 as call be ascer tallled, a corrlplete list uf iehelenccs peitaining- to ll/fenidtn ~ n ~ n r d r a witl-I he exccptlon of work o n paia5iteb.

AXDERSON, A. IT. and E. A POWER. 1950. Flshery Statistics of the United States, 1946. U. S. F i sh and Wildl i fe Semlice, Statistical Dzyest 19. Pp. 118.

BAIRD, SPENCER F. 1855. Report on Fishes Obser-ved on the Coasts of New Jersey and L o n g Island during the Sutllmer of 1854. hTi?zth Annual R a p o ~ t o f thr Srnitlzsonian l n s t z t u t i o ~ ~ , 1854. Pp. 338-339.

BEAN, TARLETON H. 1901. Catalogue of the Fishes of Long Island. Six th Anr~tual Report of the Fuuest, Pislz, a~zd G a m ~ Com~nissiofi of h'ezu Y o r k , 1900. Pp. 413.

BEAN, TARLETON H. 1903. Cabalogne of the Fishes of New Yvrk. ATeiu Y o ~ k State AW~~seztrn, Bulletin 60, Zoology 9 , 1903. Pp. 357-359.

BEAN, TARLETON H. 1908. Food nrld Garv~e Fishes of A'ew Yod: . Pp. 362-36:3.

BEAN, TARLETON H. 1888. Report of the Fishes Observed in Great Egg Warhor Bay, New Jersey, during the Sumnier of 1887. B~rl le t in , United Sfaten Fish Co?nmiss7on, Vol. VII, 1887. Pp. 146.

BIGELOW, HENRY B. and WILLIAM W. WELSH. 1925. F ~ s h e s of thz Gulf .of Mane. Blilletzn, Uizited States Burea7~ oj Fisl~eq~ies, Vol. XL, Pt. 1, 1924. Pp. 178-181.

BREDER, CHARLES &I. 1929. Field Book oj 3Iari1ze Fishes o n tho Atlu?ttic Coasts j 1 1 . 0 ~ 2 Labrador to T ~ z u s . Pp. 111-112.

BUMPUS, HEPV'RY C. 1898. The Breeding of An~rnals at Woods Hol; during Lhe Months of June, July, land Sugust. Science, V J ~ . VIII, No. 207, 1898. Pp. 854.

CLARK, EUGENIE and JAMES M. MOULTOP;. 1949. Embryolcgical Notes on PIenidin. Copeia, 1949, No. 2. Pp. 158-154.

EVERMANN, BARTON W, and SAMUEL !$. HILDElBRAND. 1010. On a Coilection of Fishes from the Lower Potoinac, the Entrance of 'Chesapeake Bay, and from Streanzi: Flomlng mbo these Waters. Pro- ceedzngs, Bioloyiec~l Society of washing to^^, Vo1. XXIII, NO. 37, 1910. Pp. 160.

FOWLER, HENRY mr. 1918. Fishes fmni the Middle Atltantic States and Virginia. Occu,sional Papers of t h p Mzcsez~w o f Zoology, Universi ty o f ~Uich iya?~ , No. 56, 1918. Pp. 17-18.

GOODE, GEORGE B. and TARLETON H. BEAK. 1879. A List of Fishes of Essex Counly, Including those of Massachusetts B,ay, i2ccording to the Latest Results 08 the Work of the United States Fish Conlmission. Bzdletin, Esses Institzcte, Vol. XI. Pp. 21.

GOSLINE, WILLIAM A. 1948. Speciation in the Fishes of the Genus ~PZenidia. Evozz~t io?~, Vo1. 11, No. 4, 1948. Pp. 306-313.

GREELEY, J. R. 1939. Fishes and Habitat Condit~ons of the Shore Zone Based on July and Angust Seining Investi&cions. A Biological Sur- vey of the Salt Waters of Long Island, 1938, Pt . 11, No. XV, Supple- mental t o the Twenty-eighth 41z7zual Report, 1938. N e ~ t York Csn- servation Department. Pp. 85.

GUNTER, GORDON. 1943. Studies on the Marine Fishes of Texas. Pub- L~ctctio?zs of t he I l z s t i t ~ ~ t e cf Marine Sc;eizce, Val. I: No. 1.; 1945. Pp. 49-50, 186.

NILDEBRAND, SARLUEL F. 1924. Kotes on Habits and DeveIop~zlelit of Eggs and Larvae of the Sllversldes ikle7zidiu n7ei7idiu and l l le~zidia be,ylli.na. Ezclletziz, Utz i t ed S t a t e s Bureaz! of Fisheries, Vol. XXXVIII, 1921-1922. Pp. 112-11s.

HILDEBRAND, SAMUEL ancl WILLIAM C. SCHROEDER. 1928. Fishes of Chesapeake Bay. Bztl let i l~, C ; ~ i t e d S t a t e s l?vi.eazi of Fislzei-ies: Vol. XLIII, Px. 1. 1927. Bp. 187-189.

JORDANU', DAVID S. and BARTON W. EVERMANN. 1896 The Fishes of North and 3Iiddle Anlerica. Bzrlletin. L'w~ted S t a t e s Nataoizal ,?iluselri.i.r, No. 47. Pt. I, lF96. Pp . 796, 800-801.

JORDAN, DAVID S. and CHARLES H. GILBERT. 1882. Synopsls of the Fishes of North Anier i~a . 3ul le t l . i~ . Uaired Stcctes N a t ~ o n a l ? ~ L L - sezcn~, No. 16, 1882. Pp, $07-409.

JORDAN, DAVI'D S. and CARL L. HUBBS. 1919. A Monographic Reviex of the Family Atherinidae or Silversides. Lela;zd St,an!toi-d J u l i i o ~ L in . i~ !e~s i t y P~rhliuntio~z~s, i3il'ive.i-sity Ser ies , 1919. Pp. 52-54.

KENDALL: WILLIAM ,I. 1962. Kotes o'n he Silversides of t h e Genus Me?ddin or" the East Coas: of t i e United States with Descriptions of Two New Subspecies. R e p o r t , United S t a t e s Co~n?nissinn o f F i s h omrd Fis I~er ies , 1901. Pp. 241-267.

K'JNTZ, ALBERT and LEWIS RADCLIFFE. 1918. Notes on the Em- bryology and Larval Deve-opment of Twelve Teleostiau Fishes. Ez~i - l e f ; ~ i , Un i t ed S t a t e s Bz[? .em~ of Fishel lcs, Vol. XXXV, 1915-1916. Pp. 127-134.

BIdNSUETI, ROMEO. 1950. An Ecoh~ica! and Dlstributiollal Study cf t h e Fishes of the Patuxent River Watershed, IUaryland. Lr,-rivei.sity o f IPui yluitcl, .clzpublished thes is , 1950. Field notes.

MARTIN. W. E. 1939. Stndies of the Trelnatodes of Woocls Hole 11. Th: Life Cycle of Stephe.izostol?zz/wt temti (Linton). Biologiccll Csrllet i i~ N3. 77, 1939. Pp. 65-73.

KERRINAN, DANIEL. 1947 Notls on the Afids~mnler 1chtht.ofaur.a of a Connecticut Eeaeh a t Di9erent Tide Levels. Copem, 1947. No 4 Pp. 281-286.

MEBRIMAN, DANIEL. 1941. Studies o'n the Striped Bass (Roeczrs saxa- tilis) of the Atlantic Coast. U. S. E'islz a n d W i l d l i f e Sel.ricc: Flshei.g Bzillati?z 35 , 1941. Bg. 52-55.

NcKENZIE, It. -4.. and L. X. DAY. 1919. The Smelt, Capeiia, a r d Silver- side. F;sAei,ies Resenrclz Eoa7.d o f Cu~zuda , A t b u ~ ~ t i e G%o!oyical S t a t i o ; ~ , C.2i.sulc~71, Geae?.al S e ~ i p s , No. 15, 1949. 4 pp.

PEARSE, A. S., H. J. HTJrUIN and G. W. WII i lRT3N. 1962. Ecology c f the Sand Beache- a: Beauford. 3. C.. Ecr~ logzca l JIonsgi a p h s , Vt-1 XlI . No. 2. =2pril, 1942. Pp. 136-190.

BEARSON, JOHX C. 1041. The Yonng of Some Marine Fishes T ~ l i e n ic. Lower Chesapeelie Sag, Virgixia, with Special Reference to the Gray Sea Trout C y ~ ~ o s C i o ~ i i - ~ g c ~ i i s (Bloch). 7:. S, F i s h and Tflildlije Se r - vice, Fis5er.y Bztlletin 36, i942. Pp. 85.

BERLALUTTER, ALFRED. 1939. -4n Ecological Survey of Young Fish and Eggs Jdentified from Tow-net CollecLions. A Biological Survey o f the Sal t Waters of Long Island, 1938, Pt. TI, Ko. XV, Szcpplci?zentnl to the Tzoentg-eight A n n t ~ u l R e p c ~ t , 1938, New YorB Con~ervation Department. Pp. 22-23, 56.

BYDER, JOHN A. lF83. On the Thread-Searing Eggs of the Silversides (.Mcnidin). H~~Eletin, United S ta te s F i sh Cornmission, Vol. TII, 1883. Pp. 193-196.

SCHUTjTZ, LEONARD P. 1948. A Revision ~f Six SSPl'nfniilies of Atherini. Fishes, with Descriptions of New Genera arid Species. P/*oeecclixgs, U S. Natio?~al J lzcse~~i~z, '01. 98, 1948. Bp. 1-48.

SMITH, HUGH M. 1898. The Fishes Found in the Vicinity of Woods Hole. B-~tlletin. United Stales Fish Co.illnzission. Vol. XVII, 1897. Pp. 94.

SMITH, HUGH M. 1907. The Fishes of North Carolina. Nortlz C~~-oli?icr. Geoiogisal and Eco1zol7iic S u ~ ~ l e g , Vol. 11, 1907. Pp. 94.

SMITH. HUGH N. 1892. Notes on a Collection of FShes from the 1.ower Poto~nac River, Maryland. Btrll~tirz, United S t a t ~ s Fish C o . ~ i ~ n ~ i s s i ~ ? z , Vol, X, 1890. Bp. 69-70.

SUNNER, FRANCIS R., EAYNOND C. QSXORN. and LEON J. COLE. 1913. A B:wlo.-ical Survev of the Waters of Woods Hole and Vicinitv. Rzilletin, United S t n f ~ s -~tuerc l t o f F i s d t e > ~ e ~ , Vul. XXXI, Pt. i1, See. 111, 1911. Pp. 743.

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WARFEE, HERBERT E. and DANIEL MERRIMAX. 1944. Studies on the Xazinc Resources of Southern Kew Bhgland, I. An Analysis of the Fish Population of the Shore Zone. Bzclletin ot +he Ei)~gha?lz Dceavuy~.npkic Collection, Vo1. IX, hi+- Z2, 1944. Pp. 1-17, 61-91.

DESCRIPTION OF TABLES

iiurnbels used to indicate gonad development are to be irlterpre~ccl

as iollo~vs:

1. Gonads firm but qrxall and underdeveloped, eggs vi>ible but

mrall.

2. Gonads larger, eggs about two-thirds lull uize.

3. Gonads ripe. eggs full si7e, rgps and milt capable of being squeezed

fiurn the fish.

4. Gonads all or partly spent, bloodshot in females wit11 i e ~ v tians-

lucent eggs, flabbr, and walery in males.

Table 2.

The numbers to tlic left of the dates rep~esent the groups into which

the data was dirided f a - length distributional anal~sis (see fig. 3 ) .

A description at' stali,ons, gears, m,ethods of measurement, and clie~mical

methods may be found under "'Materials and Methocis." "EEo~L" refers

to the number of hauls when seines tt7eue used or to the number of

minutes spent wll'en a ,dipnet was used. Under "Nurnber- of Spcci-

mens," whcri a number is f o l l o ~ ~ e d 63)- mother in parenthesis, the

Eormer is an eatinlate od the m a 1 number caught and t11e lattel- is tile

number fi-oin ~vhich the data war taken.

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