Different Lineages, Shared Strategies: Trail Cameras Reveal Similar Incubation Behavior in Wood Ducks and Hooded Mergansers in Louisiana and Mississippi

Madeleine E. Gess^1,*, Dylan L. Bakner², Katie E. Miranda¹, Michael D. Kaller¹, and Kevin M. Ringelman³

¹School of Renewable Natural Resources, Louisiana State University, Baton Rouge, LA 70803.²Department of Natural Resources Science, University of Rhode Island, Kingston, RI 02881.³Department of Wildlife, Fish, and Conservation Biology, University of California - Davis, Davis, CA 95616. *Corresponding author.

Southeastern Naturalist, Volume 25, Issue 1 (2026): 52–72

First published early online: 19 February 2026

Abstract
Incubation behavior reflects how birds balance the thermal needs of developing embryos against their own requirements for self-maintenance, with consequences for nest survival and hatching success. This behavior is expected to vary among species based on evolutionary history and life-history strategies. We used motion-activated trail cameras to compare incubation-recess behavior of 2 cavity-nesting ducks, a perching duck (Aix sponsa [Wood Duck]) and a sea duck (Lophodytes cucullatus [Hooded Merganser]), both using nest boxes in Louisiana and Mississippi. Despite differences in life history and foraging ecology between perching- and sea-duck guilds, the species exhibited broadly similar nest attentiveness. Wood Ducks averaged 2.55 ± 0.58 recesses per day, and Hooded Mergansers averaged 2.49 ± 1.12 recesses per day, and daily incubation constancy was similar (87.1% vs. 86.9%). In contrast, recess timing differed consistently between species. Wood Ducks initiated morning recesses earlier (06:54 ± 0.58 h) than Hooded Mergansers (09:01 ± 0.76 h), whereas Hooded Mergansers tended to recess earlier in the afternoon (15:18 ± 0.40 h) than Wood Ducks (16:19 ± 1.12 h). Within species, Wood Duck morning recess duration decreased with increasing clutch size (-7.9 ± 2.9 min/egg), while Hooded Merganser morning recess duration declined across incubation (-5.6 ± 1.9 min/day). Overall, the clearest divergence between species occurred in recess timing rather than the intensity of incubation behavior.

Download Full-text pdf (Accessible only to subscribers. To subscribe click here.)