Win, lose or draw: a comparison of fight structure based on fight conclusion in the fallow deer

Fights between male fallow deer (Dama dama) may conclude with the contest decisively resolved in favour of one animal (the winner), or, there may be an inconclusive resolution, in which case there is no winner. We sought to compare the structure of fights between male fallow deer in order to determine what factors might be important in influencing how fights are concluded (i.e., decisively or inconclusively resolved). We compared differences in the number of backward pushes, jump clashes and retreats over fight duration; we also compared the duration of bouts of fighting. Fights that were decisively resolved had a significantly higher number of backward pushes and jump clashes than fights that were inconclusive. Decisively resolved fights also had a higher number of retreats in the final quarter of contests suggesting that, overall, fights that resulted in a winner were more costly than fights that were inconclusively resolved. There was a significantly larger asymmetry between opponents in decisively resolved fights in the proportion of backward pushes and jump clashes recorded suggesting that opponents in fights that ended inconclusively were more evenly matched. There was no difference in overall contest duration or the duration spent fighting between decisively and inconclusively resolved fights. These results indicate that the manner by which a contest concludes, is determined by the difference in action performance between contestants and also, a difference in the rate of behavioural actions as a function of time spent fighting.