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Eggshell fragments were found below tree in lower Alder Creek.
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Another view showing deformed limbs with platforms.
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In September of 1993, consultants cruising timber stands in lower Alder Creek encountered eggshell fragments that were later confirmed as being occupied by Marbled Murrelets. Since this discovery, lower Alder Creek has intrigued many biologists because the habitat used by murrelets here is so radically different from other areas where murrelets nest. This area really bucks the trend when it comes to the habitat characteristics commonly cited as important to murrelet occupancy and reproduction.
The following information was obtained from a memorandum distributed to the California Department of Fish and Game, the United States Fish and Wildlife Service, and several murrelet biologists in the region.
Nest Site
The location where eggshell fragments were found is approximately three acres in size and is largely dominated by Douglas-fir (Pseudotsuga menziesii). Other species within the stand include California bay (Umbellularia californica), Pacific madrone (Arbutus menziesii), canyon live oak (Quercus chrysolepis), California nutmeg (Torreya californica). Vegetative characteristics were measured within a 30-meter radius circular plot centered at the possible nest tree. Douglas fir trees within the plot had a mean diameter at breast height (DBH) of 28.6 inches and a mean height of 92.3 feet. Three trees within the plot were aged to ca. 85 years using an increment borer at breast height. The stand has a single canopy layer and a crown closure around the nest tree of approximately 30 percent.
'Nest' Tree
The possible nest tree is an 85 year-old Douglas fir having a DBH of 51.2 inches and a height of 121 feet. This tree is located on the lower third of the slope (elevation 640 feet), which has an aspect of 164 degrees and a declination of 98 percent. The nearest perennial source of water, Alder Creek, is located 600 feet downslope. The closest opening to this site in an abandoned logging road located 180 feet upslope.
'Nest' Stand
The stand surrounding the three acre 'nest' site is comprised of coast redwood (Sequoia sempervirens) and Douglas fir trees that are 10-20 inches in size (DBH) with a canopy closure of 40-70 percent. This stand, which has a history of timber harvest and no evidence of fire, is approximately 60 acres in size.
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