Cerorhinca monocerata: Rhinocerous Auklet -The Race Rocks Taxonomy


This Rhinocerous Auklet was photographed by Ryan Murphy in Race Passage, late September, 2009

Rhinocerous auklet are frequent fall and winter visitors in the waters around Race Rocks. They forage for feed by diving in groups. The pictures above are of the same group, shown in different positions . Click for enlarged version
Domain Eukarya
Kingdom Animalia
Phylum Chordata
Sub-Phylum Vertebrata
Class Aves
Order Charadriformes
Family Alcidae
Genus Cerorhinca
Species monocerata
Common Name: Rhinocerous Auklet

Other Members of the Class Aves at Race Rocks.

taxonomyiconReturn to the Race Rocks Taxonomy
and Image File
April 2009 Raisa Mirza

Larus thayeri: Thayer’s gull – The Race Rocks taxonomy

Thayer’s Gulls aligned for wind, November, 2005

Domain Eukarya
Kingdom Animalia
Phylum Chordata
Class Aves
Order Charadriliformes
Family Laridae
Genus Larus
Species thayeri
Common Name: Thayer’s Gull

History: Formerly considered as a subspecies of Herring Gulls. It is sometimes regarded as a subspecies of Iceland Gulls.

Physical Appearance:22 1/2″ – 25″ wide Mantle slightly darker grey Grey on the underside of the wing tips is distinctive. Yellow bill with red spot on lower mandible. Pale to brown eyes, with a purple-red ring around it. Darker pink legs.

Sound: Long mewing call: hiyah
Warning call:
 gah-gah-gah

Nesting: Usually 2 or 3 olive-brown, heavily blotched eggs in grass nest on sea cliffs in the high arctic. They only overwinter at Race Rocks, feeding on the small herring and krill in the surrounding waters.

Habitat: They are seabirds of the arctic, coastal rocks and rocky headlands. They are usually located on the Pacific coast on North America during winters. At Race Rocks, they often number in the hundreds out on the South West corner of the larger island, as the numbers below show.

Immature Gulls: They are similar to herring gulls, but slightly smaller and with proportionately smaller bill.

Other Members of the Class Aves at Race Rocks.
taxonomyiconReturn to the Race Rocks Taxonomy
and Image File
pearsonlogo2_f2The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote control webcams. March 8 2003- Kevin Mingyui Chau

Uria aalge: The Common Murre- The Race Rocks Taxonomy

Common Murre – photo by Raisa Mirza

Where at Race Rocks?: Flocks of several hundred common murres will be seen in the waters of Race Passage from August to October, with smaller numbers staying around through the winter. They usually come ashore at Race Rocks only if they have been oiled in an oil spill in the Strait. Occasionally there will be high mortality to large flocks of these birds in the strait of Juan de Fuca when they are caught in fish nets at night.

Domain Eukarya
Kingdom Animalia
Phylum Chordata
Class Aves
Order Charadriiformes
Family Alcidae
Genus Uria
Species aalge
Common Name: Common murre

Interesting local ecology/behavior/adaptation: Common murres are usually a length of 14 inches. They are an immature-like, basic-plumaged adult but often with a thin, pointed bill and small, rounded tail. Blurry streaks make its flank appear dusty, and this thin white trailing edge is visible at rest. Its head, neck, back, wings, and tail are all blackish, and its breast, belly, foreneck, and undertail are white. A dark line extends from its eye across its cheek, and its white breast meets its dark neck as a blunt, rounded intrusion. Both sexes are very similar. Common murres often raft on the surface of the water, fly in lines, and stand erect.

This rare image of a Common murre ashore on the island was photographed by Pam Birley with remote camera 5 on the West side of the island at Race Rocks in August 2009– See Pam’s other images of this murre in her August log .

Distribution elsewhere: All coast of the Northern Hemisphere where cold currents of upwellings nourish a multitude of fish. In the west, they nest in colonies in western Aleutians and from Arctic Alaska to central California. They are found on the ocean or in large bays.

Reproduction and feeding particulars: Eggs of common murres are produced one at a time and are variable in colour, coming in blue, green, or buffy with darker blotches. They are long and pear shaped, and are laid on inaccessible cliff tops on vertical, narrow ledges, especially on rocky islets or head lands. Each nest has enough space for one egg and one incubating parent. Breeding is their main purpose of coming to shore.

Reference: Peterson, Roger Tory, Peterson Field Guide to Western Birds, New York, Houghton Mifflin Company, 1990

Udvardy, Miklos D.F., The Audubon Society Field Guide to North American Birds, New York, Chanticleer Press, 1977

Common murre – http://www.mbr-pwrc.usgs.gov/id/framlst/i0300id.html

n sea clifts. They are accomplished divers that “fly” under water in pursuit of a small fish.
Other Members of the Class Aves at Race Rocks.

taxonomyiconReturn to the Race Rocks Taxonomy
and Image File
April 2009 Raisa Mirza