Strong and others 



Chapter 32 



Distribution and Population Estimates in Oregon 



Table 3 Mean density of Marbled Murrelets per km 2 from air, vessel, and shore-based surveys in the summers of 

 1992 and 1993. Km = km of coastline travelled by vessel, used in extrapolating density to population estimates. 

 Sample size n refers to number of days surveying (vessel, shore) or number of overflights by each observer (aerial, 

 see methods). C. V. = coefficient of variation (V i 100, where s = standard deviation and x = mean) 



1 The 2 1 July transect density of 29.4/km 2 (line) or 24.2/km 2 (strip) was not included here, see text. Vessel offshore 

 densities varied with distance from shore and are shown in figures 5 and 6. 



348 



USDA Forest Service Gen. Tech. Rep. PSW-152. 1995. 



