Chapter 5: Nesting Biology and Behavior of the Marbled Murrelet

Abstract

We summarize courtship, incubation, feeding, fledging, and flight behavior of Marbled Murrelets (Brachyramphus marmoratus) using information collected at 24 nest sites in North America. Chick development, vocalizations given by adults and chicks at the nest, and predator avoidance behaviors are also described. Marbled Murrelets initiate nesting as early as March. Females lay a single egg and both adults participate in incubation, exchanging duties every 24 hours at dawn. Most incubation exchanges occur before sunrise. Chicks hatch after 27-30 days. Adults feed chicks single fish up to 8 times daily, but most feedings occur at dawn and dusk. Dawn feeding visits occur over a wider time period than incubation exchanges, with some occurring as late as 65 minutes after official sunrise. The timing of incubation exchanges and feeding visits are affected by weather and light conditions, and adults arrive later on cloudy or rainy days. To minimize the attraction of predators, visits to the nest are inconspicuous, with adults entering and exiting the nest during low light levels, and primarily without vocalizations. Because of this seabird’s secretive behavior, our understanding of murrelet demography, nest site selection, and social interactions remain limited.

Parent Publication

• Ecology and conservation of the Marbled Murrelet

Citation

Nelson, S. Kim; Hamer,Thomas E. 1995. Chapter 5: Nesting Biology and Behavior of the Marbled Murrelet. In: Ralph, C. John; Hunt, George L., Jr.; Raphael, Martin G.; Piatt, John F., Technical Editors. 1995. Ecology and conservation of the Marbled Murrelet. Gen. Tech. Rep. PSW-GTR-152. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture; p. 57-68