BIOLOGY AND CONSERVATION OF THE COMMON MURRE 1 05 



count (Osbome 1972). However, 2,500 breeding pairs 

 were reported in 1969 by Osborne (1969). Osborne 

 (1972) reported 10,000 breeding pairs in 1970. On 18 

 July 1976, 1,200 murres were reported at False Klamath 

 Rock (T. Schulenberg. American Birds Files and personal 

 communication). 



Redding Complex 



Osborne (1972) reported that Clay told him that 

 murres bred on Redding Rock in the 1930s. No reference 

 to this observation or any visit to Redding Rock was 

 reported on paper by Clay (HSU-SCL unpublished field 

 notes). Osborne (1971) and Osborne and Reynolds 

 (1971) noted 200 breeding pairs at Redding Rock in 

 1969. Osbome (1972) noted 300 breeding pairs in 1970 

 based on an aerial survey on 12 May. A navigational 

 aid light was placed on Redding Rock prior to the 

 1950s. Annual maintenance activities by the U.S. Coast 

 Guard have affected the colony (see Chapter 2 text). 



Trinidad Complex (Green Hock, Flatiron Flock. 



Pilot Hock, Blank Hock, White Hock, 



and Sea Lion Hock) 



Trinidad Bay was discovered on 9 June 1775 by 

 Juan Francisco de la Bodega y Cuadra aboard the 

 Spanish ship Sonora (Coy 1929). The pilot A. Mourelle 

 noted: "At the entrance of the port is a small island of 

 considerable height, without a single plant upon it [Pilot 

 Rock]; and on the sides of the coast are high rocks, 

 which are very convenient for disembarking [e.g., 

 Flatiron Rock]; ..." Thus, some harvesting of seabirds 

 or their eggs may have occurred. In late June and early 

 July 1817, the British ship Columbia visited and the 

 chief officer noted: "This bay is full of high rocks, which 

 are always covered with birds, and round it are scattered 

 many Indian villages." Trinidad was one of the first 

 settlements along the northern California coast, 

 established in 1 850. These rocks probably were egged 

 heavily by early residents but egging by native people 

 also probably took place because of the accessibility of 

 these colonies by canoe from the Yurok village of Tsurai 

 (Heizer and Mills 1991). On 2 July 1897, murre eggs 

 were collected from unidentified "rocks off the coast of 

 Humboldt Co." (probably off Trinidad) for A. M. Shields. 

 A total of 72 eggs were found in the WFVZ collection 

 (set numbers between 3 and 198). On 18 July 1900, 

 murre eggs were collected from unidentified "rocky 



islands of the coast of Humboldt Co for L. Kessing." 



A total of 343 eggs were found in the WFVZ collection 

 (sets of 20 eggs each, set numbers between 1 and 133); 

 thus, as many as 2,660 eggs may have been collected. 

 On 28 June 1901 . at least four murre eggs were collected 



from unidentified "islands off Humboldt County . . . 

 collected by a sailor for W. L. Chambers" (WFVZ 

 47,401-47.402; 47,664; 80,928). This group of colonies 

 near Trinidad in Humboldt County probably were the 

 breeding rocks in Humboldt County referred to by 

 Dawson(1923). 



Green Rock was first reported as a breeding colony 

 in 1930s by Talmadge (Osbome 1972). On 1 1 August 

 1938, Clay (HSU-SCL unpublished field notes) reported 

 finding a dead murre "in the surf at mouth of Luffenholtz 

 Creek, 2 miles south of Trinidad ... California Murre 

 nest on fishermen's rock [i.e., Green Rock] 1 Vt miles 

 north of Trinidad." On 10 May 1941, Clay (HSU-SCL 

 unpublished field notes) noted a substantial colony at 

 "Fishermen's Rock" (i.e., Green Rock) and described it 

 as follows: "A considerable colony of California Murres 

 nest on this bold, rather round dome 1 25 feet above the 

 waterline. I have worked other rocks along this locality 

 many times in past years; but never this particular one; 

 it being the only accessible one with a murre rookery in 

 these parts... I doubled back and up an sought ridge of 

 easy going soon to hear the incessant grumbling roar of 

 the approximately 2000 California Murres which were 

 packed tight on the very top of the rocky dome. I was on 

 a rather, grassy flat 1 feet wide running in a circle at the 

 bottom of a 6 foot wall, just out of sight of the murre 

 colony." These notes and the lack of observations at 

 other nearby islands suggest that murres only bred on 

 Green Rock in the Trinidad area from at least 1910 to 

 the early 1940s. W. Anderson (HSU-SCL unpublished 

 field notes) reported murres as "numerous on sea cliffs, 

 Trinidad" on 15-16 May 1943 and "A few left on rocks 

 off Trinidad" on 15 August 1943. These observations 

 appear to refer to Green Rock alone, but also may refer 

 to Flatiron Rock (see below). Murres were not reported 

 on the cliffs of Trinidad Head in 1910-40 by Clay (HSU- 

 SCL unpublished field notes) who conducted extensive 

 collections in this area. Anderson (HSU-SCL 

 unpublished field notes) also noted murres breeding, 

 probably at Green Rock and Flatiron Rock, in 1947 

 (see below). On 10 June 1948, two eggs (set number 

 236) were collected from a "large colony on island near 

 Trinidad" (probably Green Rock but possibly Flatiron 

 Rock; see below) by A. Andresen (WFVZ No. 68,333). 

 Osbome (1969) reported 1.200 breeding pairs in July- 

 August 1969. Osborne (1971) and Osborne and 

 Reynolds ( 1 97 1 ) noted 1 0,000 breeding pairs of murres 

 in 1970. In fact, counts ranged between 6.000 and 20,000 

 birds on various dates in April-June 1970 and colony 

 attendance began in February 1970. Osborne (1972) 

 reported 20.000-24,000 breeding pairs in 1969-70. If 

 a k correction factor was applied to 1 970 counts, a range 

 of 10,000-33,000 breeding birds or 5,000-1 7,000 pairs 



