Table 2. — Numbers and percentages of barnacles [Lepas (Dosima) fascicularis and Lepas 



(Lepas) pacifica] on various substrates. 



The most common barnacle-bearing substrate 

 was foimd to be bird feathers (90 items). The next 

 most common were leaves of the surfgrass Phyl- 

 lospadix (86 pieces) and tar (57 lumps). Other sub- 

 strates included bits of brown algae Colpomenia, 

 Egregia, Halidrys, Macrocystis, Sargassum, 

 Scytosiphon; leaves of the sea grass Zostera; pieces 

 of wood; cigarette filters; peanut shells; and plastic 

 drinking straws. (Pieces of other debris without 

 barnacles, such as polystyrene cups and plastic 

 bottles and caps — many clearly of local origin — 

 were not collected and are not further discussed 

 here.) 



Most of the barnacles belonged to two species: 

 Lepas (Dosima) fascicularis Ellis and Solander, 

 the soft blue barnacle (about 75% of the individu- 

 als); and Lepas (Lepas) pacifica Henry, a common 

 Pacific goose barnacle (about 25%). Two other 

 species of barnacle were also found: three speci- 

 mens of Tetraclita squamosa on pieces of Mac- 

 rocystis stipe, and one young specimen oi Lepas 

 (Lepas) anatifera on a piece of tar. These have not 

 been included in the data of Tables 1 and 2, and 

 will not be considered further. 



Unattached (Figure lA, B) 



An appreciable number of the Dosima speci- 

 mens (61) were found unattached to flotsam, 

 either occurring singly, each with its own float, or 

 else with several specimens sharing a communal 



float. Whether these had previously been attached 

 to any substrate was not determined. The 13 unat- 

 tached Lepas specimens found in our collections 

 had probably become detached from substrates 

 after they were collected. 



Feathers (Figures ID, 2 A, B) 



The feathers bearing barnacles were mostly 

 large, more than 10 cm long, and were relatively 

 intact with both quill and vanes. Most were white 

 or grey; the species of seabirds from which they 

 originated were not identified. Though a few of the 

 barnacles were attached singly along the shaft, 

 most occurred in clusters, generally near the dis- 

 tal end of the feather. Such clusters comprised as 

 many as 20 individuals of different sizes, many or 

 all of which must have contributed to the com- 

 munal bubble floats which in some specimens 

 reached a diameter of almost 20 mm. The largest 

 Dosima specimen found on a feather was 20 mm 

 long; the largest Lepas, only 13 mm. About 50% of 

 the feathers bearing barnacles had only Dosima 

 specimens; only seven (7.8%) were found carrying 

 Lepas alone, and on all of these the barnacles were 

 rather small and few. On the feathers that carried 

 a mixture of both species, the majority of the ani- 

 mals were Dosima; in fact, some 18 of the Lepas 

 specimens (all less than 10 mm) were found at- 

 tached to the larger individuals of Dosima. The 

 highest cluster numbers found on single feathers 



214 



