Biology ETDs

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Seven hundred and forty-four specimens of the Rio Grande mountain sucker collected in Jemez Creek, a tributary in the Rio Grande system, were measured, sexed and aged. Both length-frequency and scale methods were used to determine the age of these specimens. The oldest males were six years of age, at which time averaged 134 mm in standard length. The oldest females were seven years of age, and average 159 mm in standard length. First spawning for both males and females occurred in the spring after they had completed three full years of life. The onset of senescence, expressed as a relatively sharp reduction in growth rate, occurred in the fifth growing season in males and the sixth growing season in females.



Document Type


Degree Name


Level of Degree


Department Name

UNM Biology Department

First Committee Member (Chair)

William Jacob Koster

Second Committee Member

William Clarence Martin

Third Committee Member

Clarence Clayton Hoff

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Biology Commons