Meeting Abstract

P3.18  Thursday, Jan. 6  The Role of Innate Metabolic Capacity in the Courtship Behavior of Male Red-Sided Garter Snakes (Thamnophis sirtalis parietalis) MICHAELSON, JB*; POWERS, DR; FRIESEN, CR; MASON, RT; George Fox University, Newberg, OR; George Fox University, Newberg, OR; Oregon State Univ., Corvallis, OR; Oregon State Univ., Corvallis, OR jmichaelson07@georgefox.edu

Red-sided garter snakes are an exceptional model for study of energetic costs of courtship and mating as they fast during the spring mating season segregating the cost of energy acquisition from the cost of courtship and mating. Male red-sided garter snakes (Thamnophis sirtalis parietalis) can upregulate their group metabolic rate (MR) 18X SMR during courtship of females. However, males within a mating group exhibit variable behavior with regard to how actively females are courted making it likely that the males courting most intensely upregulate MR higher than the group mean. To test if a male’s courtship ability is related to metabolic performance we measured resting metabolic rate (RMR), courting metabolic rate (CMR), and metabolic scope (MS; CMR-RMR) in single males collected from natural mating groups. During CMR measurements a courtship score (CS) was calculated to correlate CMR with courtship activity. We tested males from mating groups that 1) copulated (A), 2) courted but did not copulate (B), and 3) were near but did not court (C). RMR, CMR, and CS did not differ between groups. CS did not differ between A and B males, but was significantly lower in C males suggesting that although C males are different from A and B males this difference is not driven by metabolic performance. Similarity of A and B males was supported by supplemental video analysis of natural mating groups suggesting that the probability of mating by these males is influenced by position in the mating group and that male position changes with female movement.