Is mate choice based on a mate’s breeding experience?

Box plots of pair age differences in the year of pair formation with respect to a mate’s breeding experience by northern goshawks in Arizona, USA. Vertical bars are medians (i.e., 50th percentile), boxes contain the central 50% of differences (i.e., bounded by the 25th and 75th percentiles), and dots are outliers. “Both recruits” pairs are both first-time breeders, “recruit/exp” pairs are male recruit/female experienced, “exp/recruit” pairs are male experienced/female recruit, and “both exp” pairs are both previous breeders. (A) Known-age hawks only and (B) hawks aged ≥4-years-old with their known-age mates where relevant.