BIOLOGY AND CONSERVATION OF THE COMMON MURRE 1 03 



and may have been the main factor leading to final 

 extirpation of this colony. The colony also may have 

 been affected in the nineteenth and early twentieth 

 centuries by undocumented human disturbance, egging, 

 hunting, deaths from oiling, climate change, or factors 

 at the southern edge of the breeding range (Hunt et al. 

 1980). Other murre colonies also could have existed in 

 the northern Channel Islands (especially at nearby 

 Castle Rock off San Miguel Island where suitable habitat 

 exists) but were extirpated before the 1880s when egg 

 collecting became focused at Prince Island. 



Northern California Colonies 



Castle Hock (Castle Complex) 



Castle Rock probably was egged heavily by early 

 residents of Crescent City (e.g., about 800 residents by 

 1854 [Smith 1989]) because of easy access by small 

 boat. The first record of murre breeding on Castle Rock 

 was an egg collected on 6 July 1894, without other 

 data, in the egg collection of C. I. Clay which is housed 

 at the museum within the Department of Wildlife at 

 Humboldt State University (HSUWM No. 605). 

 Numerous eggs were collected from Castle Rock 

 between 1917 and 1 935, after the South Farallon Islands 

 and Prince Island no longer provided specimens for 

 collectors (see above). On 20-22 July 1917, C. I. Clay 

 collected at least 4 eggs and murres were noted only as 

 "seen" (HSUWM Nos. 345-347, 1387; C. I. Clay, 

 unpublished field notes in the HSU Special Collections 

 Library [HSU-SCL]; see Osborne 1972). On 23 June 

 1923. at least two eggs were collected, without other 

 data (HSUWM Nos. 1615, 1618). On 18 May 1925, at 

 least one egg was collected (HSUWM No. 1088). On 2 

 June 1 924, F. J. Smith (probably with C. I. Clay) collected 

 at least five eggs; two eggs were marked as sets numbers 

 3 and 10 (WFVZ Nos. 32,111; 32,115) from a "small 

 nesting colony." whereas three other eggs had the same 

 date, without other data (HSUWM Nos. 309, 1614, 

 1616). On 23-25 June 1925, F. J. Smith and C. I. Clay 

 collected at least seven eggs and one small chick that 

 was found dead (MCZ 328596). Two eggs were marked 

 as set numbers 2 and 40 (WFVZ Nos. 73,885; 140,5 13) 

 and three eggs were marked as set numbers 1, 2, and 3 

 (MCZ 9421-9423). whereas two other eggs had the same 

 dates without other data (HSUWM Nos. 1386, 1613). 

 One other egg bore only the date 1925 (HSUWM No. 

 1623). Clay (unpublished notes in the HSUWM egg 

 collection) made a list of eggs of several seabirds 

 collected at Castle Rock on 24 July 1925, noting 50 

 murre eggs collected. In June 1 926. at least one egg was 

 collected (HSUWM No. 1621), whereas one other egg 

 bore only the date 1926 (HSUWM No. 1617). On 22- 

 24 June 1928. F. J. Smith and C. I. Clay collected at 



least 10 eggs (WFVZ No. 73,886; BMVZ Nos. 13,284- 

 13,291; HSUWM No. 296). Clay (unpublished notes in 

 the HSUWM egg collection) made a list of eggs of 

 several seabirds collected at Castle Rock on 24 June 



1928, noting 100 murre eggs collected. On 17-18 May 



1929, F. J. Smith (probably with C. I. Clay) collected at 

 least 1 5 eggs: three eggs were marked with set numbers 

 9, 10, and 16 (WFVZ Nos. 37,036; 73,887; 73,888), 

 whereas 1 2 eggs had no other data (HSUWM Nos. 293, 

 294, 302, 310, 340-344, 684 [note: HSUWM Nos. 340, 

 342, and 344 include two eggs per specimen number]). 

 On 25 May 1929, J. T. Fraser collected at least one egg, 

 marked as set number 3/29 (WFVZ No. 88,133). On 9 

 July 1929. G. D. Atwell collected at least three eggs, 

 marked as set numbers 117-119 (HSUWM Nos. 1738- 

 1740). On 18 May 1930, L. Zerlang and J. T. Fraser 

 collected at least four eggs: three eggs were marked 

 with Zerlang's set numbers 1 , 2, and E5, and one egg 

 was marked with Fraser's set number 2 (WFVZ Nos. 

 37,036; 73,887; 73,888). On 28 June 1930, at least six 

 eggs were collected, probably by C. I. Clay (HSUWM 

 Nos. 295, 299, 669, 671, 675, 676). On 20 May 1931, L. 

 Zerlang collected at least one egg, marked as set number 

 4 (WFVZ No. 47,408). On 27 June 1931, at least four 

 eggs were collected, probably by C. I. Clay (HSUWM 

 Nos. 297, 298, 300, 301). On 12 June 1932, L. Zerlang 

 and J. T. Fraser collected at least four eggs: two were 

 marked with Zerlang's set numbers 17 and 57, and two 

 with Fraser's set numbers 332 and 532 (WFVZ Nos. 

 46,406; 47,409; 88,111; and 88,113). 



On 20 May 1934, C. I. Clay collected at least ten 

 eggs, of which nine eggs are in the HSUWM collection 

 (HSUWM Nos. 1,089; 1,090; 1,095; 1,096; 1,098: 

 1,100; 1,105; 1,107; and 1,680). Clay (HSU-SCL 

 unpublished field notes) provided additional 

 information for each egg collected (field nos. 2305- 

 2310, 2313-2317), including the following notes of 

 interest: No. 2305 (HSUWM No. 1,100) - "Colony 

 murres on north side and about 1 00 feet above sea level; 

 large colony with eggs close together"; No. 2,306 

 (HSUWM No. 1095) - "All the eggs in 3 major colonies 

 were laid on bare rock; in some cases extremely rough"; 

 No. 2,310 (HSUWM No. 1090) - "... taken on extreme 

 top of the highest peak on rock. Estimated 167' above 

 sea level"; No. 2,313 (HSUWM No. 1089) - "... in large 

 colony on extreme seaward side of island"; No. 2,315 

 (HSUWM No. 1,089) - "This egg placed in center of 

 large colony of murres on the east side of the island. 

 Birds in this colony touched each other, while on the 

 nest, they were so thick. This colony laid eggs right out 

 to the edge of a more than 100 foot cliff..."; and No. 

 2,316 - "Same nesting side as the last runt egg [i.e., No. 

 2,315]... The colony was the most compact nesting of 



