|
<br />
<br />)
<br />)'6
<br />
<br />/ ,;ik/(~)/tf },,',4J
<br />
<br />QJJ2L
<br />
<br />.D~uql(j~ I ~ !lq62
<br />
<br />:OMMISSION
<br />
<br />ilme Commission of
<br />\\'ing resolution:
<br />as a member of th"
<br />lllber 19, 1939; as
<br />to .J anuary 9, 1948,
<br />
<br />aI'S I-,ee Payne has
<br />. the State of Cali.
<br />
<br />Id
<br />. Pavne has meril e(l
<br />e p~rsonnel for his
<br />e his unerring keell.
<br />firm decisiveness on
<br />the fish and gal1ll'
<br />
<br />~iates that the C<lll.
<br />e has been furthel,,'(1
<br />IV, therefore, be it
<br />; commission and ..{
<br />,ed to Commissio)! e1'
<br />resident of the c,.]!i.
<br />~'ears, together 'v i \ Ii
<br />o serve as an acti,e
<br />
<br />rwarded to the C;,,\,.
<br />I' Payne of the }':si,
<br />I' offi~ial journal, 1)1'
<br />l, of Fish and G311le,
<br />
<br />NOTES ON THE SPAWNING OF THE HUMPBACK SUCKER,
<br />XYRAUCHEN TEXANUS (ABBOTT) 1
<br />
<br />By PHILIP A. DOUGLAS
<br />Bureau af Fish Conservation
<br />California Department of Fish and Game
<br />
<br />INTRODUCTION
<br />
<br />The humpback sucker, Xyrauchen texan1ts (Abbott) is one of the few
<br />Jlative fishes remaining in the lower Colorado River drainage. In the
<br />l'pring of 1950 the writer made some observations on its spawning activi-
<br />ties in I,ake Havasu (an impoundment of the Colorado River), San Ber-
<br />nardino County, California. Other writers (see references) have pub-
<br />lished material on the humpback sucker, and some of these have recorded
<br />sexually mature fish, but none of them has included information on the
<br />:-pawning activities of the species. Thus, the ,'Titer believes that his
<br />presently described observations, incomplete as they are, are wortby of
<br />record in published form.
<br />A general description of the lake, spawning locale, spawning observa-
<br />tions, and collections in chronological order, are presented here.
<br />
<br />GENERAL DESCRIPTION OF LAKE HAVASU
<br />
<br />Water storage in this basin began in October, 1938, following comple-
<br />tion of Parker Dam. The total capacity of Lake Havasu is 770,000 acre-
<br />fret, its maximum area is 20,000 surface acres, and its maximum depth is
<br />I\:! feet. In 1950 the mean air and water temperatures were 74 degrees
<br />F. and 70 degrees F., respectively, while the air and water temperature
<br />ranges were 29.127 degrees F. and 42-85 degrees F.) respectively. Mean
<br />rainfall in this Lower Sonoran Life Zone was 6.0 inches for this veal'. A
<br />brief chemical analysis made at Lake Havasu on October 10, 1950, by
<br />:lletropolitan ,Vater District hydrologists C. C. Elder and L. D. Martin
<br />i~ as follows: pH 8.3 at 23 degrees C. ; ph-th 3 p.p.m. ; M.O. 125 p.p.m. ;
<br />hardness 311 p.p.m. CaC03; CaC03 125 p.p.m.; Ca(HC03h 186 p.p.m.;
<br />Mal alkalinity 618 p.p.m. CaC03; free CO2 1.0 p.p.m.; electrical con-
<br />lluetivity 994 reciprocal megohms. High winds are generally prevalent
<br />iiuring the spring months. No stratification occurs because of the constant
<br />oYerturn in this shallow (average depth approximately 30 feet) lake.
<br />Current velocities are practically zero.
<br />
<br />'SUbmitted for publication November, 1951. In view of the recent adoption of the
<br />common name "humpback sucker" in place of "razorback sucker" by the American
<br />l"isheries Society, the California Department of Fish and Game is taking a similar
<br />course.
<br />
<br />( 149 )
<br />
|