Pacific Banana Slug

We discovered our first Pacific Banana Slug on our driveway in Olympia on 5 April 2019. These slugs are the second largest species of terrestrial slug, growing up to almost 10 inches. (The largest, which grow up to a foot, are found in Europe.) Colors vary from yellow to tan or white. Their black spots can make them appear to be black. The colors also vary with food, light, moisture and/or health of the animal. Banana Slugs are prone to desiccation. To avoid drying out, they often secrete a layer of slimy mucus. They remain inactive in dry conditions and are often most active at night.

Banana Slugs are found from southeastern Alaska to Santa Cruz, California. They inhabit coastal coniferous rainforests. These slugs eat dead leaves, small plants, and animal excrement and recycle these materials into the soil. They consume mushrooms and spread mushroom spores. The slugs have a number of predators, including raccoons shrews, moles, garter snakes, waterfowl, and salamanders (Wikipedia). 

American Dipper

On 12 April, Erika and I hiked along Tumwater Falls, a city park in the middle of Olympia. We saw American Dippers there on a previous visit. Dippers are thrush-like, gray birds that feed along mountain streams. They are our only truly aquatic songbird, often submerging completely in search of food. On this trip, however, we thought way too much water cascaded down the falls for even dippers to handle.

Dippers used to be named Water Ouzels. The name was changed to dipper to conform with nomenclature of the four other dippers in other parts of the world. Dipper species are found North and South America, Europe, and Asia. The word dipper describes the bird’s habit of bobbing up and down at the water’s edge, alsmost if the bird was exercising. My father, who took us boys on our first birding forays in central Mexico, took delight in Blake’s calling these movements spasmodic bobs.

Dippers give the impression of being closely related to thrushes, and early traditional DNA research suggest that is the case. Willson and Kingery 2011 report that recent mitochondrial DNA research indicates that dippers are more closely related to starlings.

Black-capped Chickadee

Seven races of Black-capped Chickadees are described from North America. Black-capped Chickadees in Olympia surprise me.  I assume they are the Pacific Coast race, Poecile atricapillus occidentalis. Their wings are at least a centimeter shorter than those of Minnesota birds. This difference may not seem very large, but it is obvious in a bird being banded. Olympia Black-capped Chickadees have far less white in the wing, and, overall, are duller and browner. They are far more different to my eye than Black-caps compared to Carolina Chickadees. I wonder what their genetics are like?

Hutton’s Vireo

A fancy bird in my banding net yesterday—a Hutton’s Vireo. The species looks like a kinglet, but note the stocky, hooked bill. The drab plumage and incomplete eye ring both suggest Hutton’s Vireo. This vireo is an uncommon resident in Washington, and ranges south across the Pacific Coast to Baja California and in the Southwestern United States south through central Mexico. I have only seen the species once before, over 50 years ago in Mexico.

Because they are drab and inconspicuous, the biology of Hutton’s Vireos is little known. Even the bird’s call is described as “persistent but insipid” (Davis 2018). Some populations, such as those in the Southwest, are migratory. Resident, non-migratory birds, like those in Washington, may wander locally, but these movements have been little studied.  Davis suggests that the Hutton’s Vireos of the Pacific Coast and Mexico differ sufficiently genetically as to warrant being considered separate species.

Chestnut-backed Chickadee

As you probably noticed in my last few bird blogs, the Federal and State authorities have authorized me to band birds here in Washington. I am grateful for these permits, since they can be difficult to obtain. Despite our living among 175 moving boxes, I did open a single net in my backyard. The first bird banded in Washington was this Chestnut-backed Chickadee.

The second bird banded was a Black-capped Chickadee. Erika and I wondered how these two similar birds coexist. Chestnut-backed Chickadees forage higher in trees than do Black-capps and are more restricted to conifers. Chestnut-backed also forage more often on the upper sides of leaves and branches. Finally, Black-capped Chickadees employ more feeding strategies than do Chestnut-backs (Dahlsten et al. 2002).

Chestnut-backed Chickadees are found from southern Alaska to southern California. In the last 50 yeas, this range has expanded a bit into the central Sierra Nevada and suburban areas in eastern San Francisco Bay. Ornithologists can not explain these changes (Dahlsten et al. 2002). 

Bushtit

Bushtits are common in our Olympia backyard. They are small but interesting birds. For one thing, females have bright yellow eyes, whereas males’ eyes are dark. Another curious fact is that Bushtits appear to have come to North America via the Bering Land Bridge some 11 million years ago. They are the only European long-tailed tit found on our continent. Despite their name, long-tailed tits are more closely related to Old World warblers or swallows than they are to titmice and chickadees (Sloan 2001). 

Pacific Trillium

Pacific Trilliums (Trillium ovatum) are blooming in our Olympia backyard. This flower is variable, ranging from white to purple. It grows in western mountains and along the Pacific coast, from California to British Columbia and Alberta. The species blooms early in the spring, and, for that reason, is also called wake-robin, They are occasionally commercially grown, although seeds take many years to germinate. The plant also propagates asexually by root growth and division, Trillium is pollinated by ants. What appear to be Trillium leaves are actually flower bracts and their stems are extensions of their roots (USDA). The true leaves are tiny, scale[like structures that grow on the roots. Although the leaves can be boiled and eaten, the berries and roots are known to be of “low toxicity” (Lady Bird Johnson Wildflower Center. This source advises caution since closely related plants are poisonous,

Song Sparrow

Song Sparrows are common in OIympia. Here in the Pacific Northwest, Song Sparrows are much darker than eastern birds. These sparrows vary greatly across their wide range across North America, from northern Mexico to central Canada. Ornithologists recognize 24 races and have, at one time or another, named twice that many. Generally Song Sparrows are darker in regions with high humidity and larger in northern areas (Arcese et al. 2002).

Northern Pintail

After many visits to Olympia, by the time we moved here my Thurston County list was just shy of 100 bird species. To my delight, this Northern Pintail at Nisqually National Wildlife Refuge on 30 April 2019 proved to be number 101. Northern Pintails are common ducks. In 2013, biologists estimated the North American population at 3.3 million, up from three million in the late 1980s and early 1990s. This sounds great, but in the early 1970s, the estimate was six million. Draught and habitat destruction combined to cause this decline. Conservation efforts, however, provide hope that populations of pintails should remain at current levels or increase (Clark et al. 2014), 

Sooty Fox Sparrow

Fox Sparrows are drab in the Pacific Northwest. This bird at our bird feeder on 29 March 2019 does not even seem like the same species as bright reddish Minnesota Fox Sparrows. This species is highly variable across its range. Eighteen races are described, which fall into three or four subspecies groups. Coastal Washington birds are most likely Sooty (aka Pacific) Fox Sparrows, which lack wing bars and have relatively short tails. Their lores, the area between their bills and eyes, are dark. The various groups of Fox Sparrow races only rarely interbreed. Ornithologists may someday split these groups into distinct species. For now, more genetic study is required (Weckstein et al. 2002). Meanwhile, if you are into listing birds, you may be wise to keep track of what kind of Fox Sparrow you find.