Oxygen Consumption Rates for Bighead and Silver Carp in Relation to Life-Stage and Water Temperature

ABSTRACT

We measured bighead carp (Hypophthalmythys nobilis) and silver carp (Hypophthalrnythys molitnx) oxygen consumption rates (M02) at several water temperatures (5—25°C) and life stages (juvenile and adult). The relation between M02 and body mass for both species was allometric, with body mass correlated to M02. The mass exponent used to correct mass-related bias (b) for bighead carp was 0.70, while the calculated b value for silver carp was 0.76. Temperature significantly affected mass-corrected M02 in both species (P < 0.05), whereas life stage did not (P > 0.05). Mean mass-corrected oxygen consumption rate ranged from 0.21 to 0.97 mg O₂hr⁻¹ and did not differ between species (P=0.60). Our results suggest that Asian carp have high metabolic rates compared to native fishes occupying a similar feeding niche. These data also suggest that Asian carp could exceed native filter-feeding species energetic demands that could have potential negative long-term effects on ecosystems in which they become established.