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Abstract
Clark's nutcrackers (Nucifraga columbiana) are well known for using conifer seeds as their principal nutriment source. Seeds are primarily harvested from whitebark (Pinus albicaulis), piñon (P. edulis), limber (P. flexilis), southwestern white (P. strobiformis), Jeffrey (P. jeffreyi), and ponderosa (P. ponderosa) pine as well as Douglas-fir (Pseudotsuga menziesii) (Tomback 1998). However, prior to our studies, sugar pine (Pinus lambertiana) seed harvest by Clark's nutcrackers was not documented. Sugar pine seeds, which bear long seed wings, are among the largest of pine seeds (average of 0.216 g; Tomback and Linhart 1990) and the cones are the longest among all pines (up to 66 cm, Kinloch and Scheuner 1990). Observations over several years in Crater Lake National Park (CLNP), Oregon, indicate that Clark's nutcrackers harvest sugar pine seeds, but only for about a week in late September when most cones open. The first observations of nutcrackers using sugar pine seeds in CLNP were made by Michael Murray from 2004 to 2006, and then more detailed studies were conducted by Taylor Turner, Brad Van Anderson, and Diana F. Tomback in 2008 and 2009, working in the old-growth sugar pine forest.
Parent Publication
Keywords
high elevation five-needle pines,
threats,
whitebark,
Pinus albicaulis,
limber,
Pinus flexilis,
southwestern white,
Pinus strobiformis,
foxtail,
Pinus balfouriana,
Great Basin bristlecone,
Pinus longaeva,
Rocky Mountain bristlecone pine,
Pinus aristata
Citation
Turner, Taylor J.; Tomback, Diana F.; Van Anderson, Bradley; Murray, Michael. 2011. Sugar pine seed harvest by Clark's nutcracker: Annual use of a transient resource in Crater Lake National Park, Oregon. In: Keane, Robert E.; Tomback, Diana F.; Murray, Michael P.; Smith, Cyndi M., eds. The future of high-elevation, five-needle white pines in Western North America: Proceedings of the High Five Symposium. 28-30 June 2010; Missoula, MT. Proceedings RMRS-P-63. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 72-73.
