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<br />]68
<br />
<br />CALTFORKIA FISH AND GAME
<br />
<br />below Imperial Dam (1); Haughtelin Lake (3) ; Haslam Slough"'
<br />Palo Verde (1); Lake Havasu (1), White crappie were collect
<br />follows: head of the Alamo Canal (2) ; mouth of the Gila River
<br />Haughtelin Lake (5) ; Headgate Rock Dam (1). In California,
<br />as is known, the white crappie is confined to the Colorado River dra:
<br />
<br />Remarks, The apparent scarcity of these fishes and the paucity of ~.
<br />material do not permit more than passing mention of their life his .
<br />or their roles in the river.
<br />The largest blaek crappies taken were 8,] inches in
<br />largest white crappie 12,0 inches, '
<br />.All black crappies seen (range, 5,7-8,1 inches) were adults. -
<br />caught in late January had well-developed gonads, Those tak
<br />May (4) were ripe. . ~'
<br />Nine white crappies 5,9 inches or over in length which wer
<br />were adults. Three ranging from 4.9 to 5.4 inches in length wer~
<br />sidered immature. The one adult :fish taken in May was a ripe fe.
<br />The others were collected in January (7) and in April (1), -
<br />somewhat swollen gonads.
<br />The stomachs of 8 out of 9 white crappie (5.1-10.0 inches inl
<br />which were examined contained food. The frequency of occllIT-
<br />food items found was as follows: chironomid larvae (8 times);
<br />crustacea, primarily cladocera' ( 5 times); backswimmers (4.:'
<br />mayfly nymphs (twice); damselfly nymphs (twice); bluegillsl.
<br />Two black crappie (5.6 and 5,7 inches long) contained ostracods..
<br />nymphs, backswimmers, and chironomid larvae, From these scant
<br />--or better, from our knowledge of crappies in other wate~
<br />assume that they ma~' offer decided food competition to the other~
<br />chids of the Colorado by utilizing both the smaller and larger
<br />foods, It is well known that crappies mayk decidedly pisel
<br />For example, studies of both species in Foots Pond; Indiana, by...
<br />and Ricker (1942) showed that over 70 per cent of the foodb$'o
<br />was composed of fish. .:
<br />Both crappies are recognized game fish or pan fish in the:.
<br />States, and .will, if the)'increase iunumbers, secure this place'
<br />Coloraao'Rlver .----.M:afiy.li.ng~ers'report-that,-fishing for-..crapJll.
<br />uncertain sport. At times they seem to biM voraciously; at oth
<br />it is most difficult to take them even from waters wherei '
<br />abundant. Only at Haughtelin Lake, where large schools we
<br />times seen, did we find people :fishing for crappies as a primaryI"'
<br />Small artificial !lITes or bait may be used for their capture. "~
<br />'Parts of California a live minnow seems to be the most killing off
<br />. 'Thompson and Bennett (1938) and Bennett (1943) hav~~
<br />,evide~eeto 8howthat crappies may be serious competitors of la.i'.
<br />cc:o;:',--:. ,bass; "',.And' in the publications of se-yeral other fisb.eriesuwQt,
<br />-nOtes a growing feeling that the presence of crappies iSinimiclt
<br />-,i:,~:' :: ~~ _,. ~st inter~ of_ a, bass fishery. Their occurrence in tJ:e~ CoI!"...
<br />.';:,,:-._ _ not be desrrable. It maY be, of course, that the competItlOn Dr
<br />~;;="c}. . :,,". ,,~,con 1(l.no.t.J1.ttamJ,.lt~~~l"!~in the more open ' 'lakes" of ,th
<br />
<br />)j!'~':~~__~'-~f:t~:S~~~n~~~:~,~era. -0~-~:--~u-.:, .', .::.
<br />
<br />,",!~ .......-:;:'"
<br />
<br />THE FISHERY OF TIlE l.oWER COLORADO RIVr:R
<br />
<br />)()9
<br />
<br />Bluegill, Lepomis .",acrocbir2ls Rafinesque
<br />
<br />l.oca7 }.:ames. Bluegill, bluegill" perell," "perch," sun perch, sunfish,
<br />
<br />I:(coQ1iit'ion Characters. The bluegill and green sunfish can be told from
<br />t llr (:i-appies by the following cbar~cters : ana} fin less tba,n half as long as
<br />d(ll'~a] : 3 anal spines; 10 dorsal spll1es, TheIr short bodIes (depth about
<br />onc-half standard length) and the presence of a black" ear flap" on the
<br />!!ill coYer easily distinguishes them from the hlack basses (Huro and
<br />,'Vicropterus). .'
<br />These two sunfislles are frequently confused lD the Colorado RlVer
<br />l\~ in many other parts of California, The following tabl~ will serve to
<br />distinl!uish them, It may be noted that these two specles frt'quentJy
<br />hybridize, and hybrids were seen at several points along the river,
<br />
<br />Character Bluegill Grccn 8tlnfi~l,
<br />l','rliull of opercular flap Thin and flexible Stiff and bon)'
<br />hearing black spot
<br />
<br />1'1'1"'1 jaw
<br />
<br />l'ot extending nearly to
<br />middle of eye
<br />
<br />Extending nearly to (or
<br />eyen be~'ond) middle of
<br />e~'e
<br />
<br />Short and rounded (4
<br />times in standard
<br />length)
<br />
<br />l'f.('\oral fins
<br />
<br />Long and pointed (at
<br />least 3 times in stand-
<br />ard lengtb)
<br />
<br />Distribution' Abundance; Habitat. The bluegill is abundant in the
<br />quiet waters'all along the lower river, and in irrigation canals where t~e
<br />water is cheeked. It is especially common in areas where the cover IS
<br />thick as 'in the brushy portions of the lakes above Imperial Dam, n~ar
<br />boat landings, etc. It seems to be the most abundant of the centrarchIds,
<br />despite the report that it is quite a newcomer to the river,
<br />
<br />Haue:hteUn La.ke, an 01bo,..,,,,he~e blueg~lls are a.bu~'d&ri(:Ji~. 1942. .
<br />. __...._ __;......"'-.A--=.---'-'_,+_.~__ ~ .u_,_,_~________,__,"_
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