Black Oystercatcher (Haematopus bachmani)

You probably have a loud, outgoing friend or two that can be trusted to make their presence known whenever they walk into a room. If you’re a resident of the intertidal community between Alaska, and Baja, California the Black Oystercatcher could be that friend. The Black Oystercatcher is a keystone species in this region and is believed to be a particularly sensitive indicator of the overall health of the rocky intertidal community. This large, long-lived shorebird measures approximately 15 inches in length with a long, thick, reddish-orange bill, a yellow eye encircled by an orange ring, and pink legs. These colors stick out against the bird’s black and dark brown plumage. In addition to its eye-catching appearance, black oystercatchers are gregarious and noisy birds, making several different types of noises to call to each other loudly and to scold other birds that may get too close to where it is feeding.

Oystercatchers inhabit marine shorelines, making their nests above the high tide line on offshore rocks, rocky shores, and sand or gravel beaches. If disturbed, they take flight with loud, ringing whistles easily heard above the sound of the waves. Despite its name, this shorebird seldom eats oysters. Instead, it feeds on a variety of intertidal invertebrates including mussels, limpets, chitons, crabs, barnacles, and other small creatures.

Black oystercatchers are highly vulnerable to natural and human disturbances. Major threats include predation of eggs and young by native and non-native predators; coastal development; human disturbance; shoreline contamination including oil spills; and global climate change. According to the U.S. Fish and Wildlife Service, the entire world population of black oystercatchers is estimated at about 11,000 individuals. More than 50 percent of that population lives in Alaska. If you have the chance to see a Black Oystercatcher next time you visit the beach in Oregon take a moment to appreciate this interesting bird, but keep your distance and help preserve this unique species.

You probably know that the bedrock along the entire coast of California and southern Oregon is comprised of a chaotic mix of rock types, generally referred to in the literature as Franciscan mélange.

Pillow basalts are among the most common of these types and are recognized by their distinctive pillow-like shape, glassy margins and interstitial calcareous mud. They form under water, in this case the Mesozoic ocean floor prior to subduction.

In addition to these rocks, there are so-called exotic blocks within the mélange. Their origin is much more problematic because they have been thoroughly metamorphosed at great depth during the subduction process. They have since been uplifted and are now found in various localities including the Bandon area. The minerals in these blocks, some as large as houses, are hard and dense, imparting great resistance to erosion. They form some of the best sea stacks along the coast.

 

The second image here is a close-up of some of these minerals. The blue mineral is glaucophane, the spherical red mineral is garnet and the green mineral is pyroxene that is rich in jadeite. People occasionally find gem quality jadeite along the beaches there. All of these minerals are strictly metamorphic, having formed at depths on the order of 20 km and temperatures on the order of 500 degrees Celsius!

 

(Thanks to Dr. Jim Stout for his insights into local geology!)

You can enhance your next visit to the coast by hiring a professional guide to reveal some stories of the fascinating coastal rock formations! One such company is Wavecrest Tours in Coos Bay

Steller’s Jay (Cyanocitta stelleri)

The Steller’s Jay (Cyanocitta stelleri) is the largest jay in North America measuring in at 12-13 inches. Like many humans, this bird knows it never hurts to have a few tricks up your sleeve. They have a few unique skills that might surprise you.

The Steller’s Jay is related to the Blue Jay but has a slimmer bill and longer legs. It is also the only western jay with a crest. The front part of this jay is black while the back, wings and tail are dark blue. This coloring helps the Steller’s Jay easily blend in with the evergreen forests of the mountainous West where it is typically found, although this bird is also known to frequent campgrounds, parks, and backyards.

This bird is very intelligent and opportunistic. Steller’s Jays usually travel in pairs or family groups. They have a complex social and communication system, with a variety of calls, postures and displays. For instance, a spread wing shows submission, and a raised crest might mean attack. Steller’s Jays may also mimic the screams of hawks and Golden Eagles. This bird feeds mainly on acorns and pine seeds, but will raid other bird’s nests for eggs and nestlings. They will also eat small reptiles, nuts, berries, fruits, and insects.  Curiously, these jays have distendable esophagi that they are able to use to carry acorns and nuts. These foods are often cached for the winter or saved for eating at a later time. What unique skills do you have up your sleeve?