Nature Watch: Fruits of the Land

About the author: Steve Ellis is a naturalist and Land Trust member who enjoys sharing his love of the natural world. His blog series, “Nature Watch,” will appear each month in “Habitchat,” chronicling native plants and wildlife you can expect to see during that particular time of year. We thank Steve for sharing his passion, illustrating the importance of island conservation.

Overview

Berries and other fruits are essential dietary components of many bird and mammal species.

At least two dozen native tree and shrub species along with a couple of herbs produce some kind of fruit. In our area, these fall into five general categories: berry, drupe (a pulpy mass surrounding a seed with a stony covering); hip (the fleshy covering around the nutlike seeds of roses); cherry; crabapple. Together they span the four seasons, with some snowberries persisting until the ripening of berries in late spring.

Fruits can also be found at every layer, from ground level to treetops, giving all birds and mammals a chance at the bounty. Wild strawberry and trailing blackberry hug the ground. Shrubs such as thimbleberry and red huckleberry extend to the understory, while bitter cherry and Pacific crabapple display their fruits thirty to forty feet in the air.

Plants produce fruits to entice birds and mammals to eat them in order for the seeds to be scattered. Seeds that pass through the digestive system of birds have a higher germination rate than those eaten by mammals or those that fall directly to the soil.

The role of fruits changes with the seasons. Salmonberries are fed to innumerable American Robin and Swainson’s Thrush nestlings whose parents are looking to provide their young with liquid in the form of juicy berries.

Red huckleberries, ripening in shaded forests, are a good food source for birds in midsummer. Robins especially retreat to forest interiors as the sun bakes exposed earth and makes worms less accessible.

The value of fruits becomes critical with the onset of fall and winter, as other food resources dwindle. The abundant sugars in fruit is converted by birds into energy needed to either survive local winters or to make the long journey southward to Mexico and beyond.

An amazing array of bird life includes fruit in their diets, such as woodpeckers, finches and sparrows. Even some shorebirds, along with warblers, swallows and waterfowl including Snow Geese and Mallards ,will take berries if they are accessible.

Mammals also binge on berries and other fruit. I’ve observed deer rear up on their hind legs to snatch mouthfuls of red elderberries and watched them slurp up wind-fallen madrone berries. Chipmunks are fond of bitter cherries, and 20% of all western yew trees get their start from caches of drupes made and then abandoned by little rodents. Townsend’s voles seek out trailing blackberries and coyotes eat fallen crabapples.

After the birds and mammals have their fill, then invertebrates feed on over-ripe remnants. Red admiral butterflies often visit rotting fruits along with wasps that are attracted by the sugars.

Fruit-bearing flora can be seen in most habitats. A stakeout with multiple trees or shrubs will certainly offer views of wildlife to a patient observer.

Red huckleberry by Martha Ellis.

Flora: Red Huckleberry (Vaccinium parviflorum)

One of the more intriguing fruit producers is the red huckleberry. This member of Vaccinium, the huckleberry/blueberry group, has traits that set it apart from its relatives.

Red huckleberry grows to an average height of 3 to 6 feet, although some specimens may attain 12 feet.  Unlike other vacciniums, red huckleberry keeps its branches and twigs green in every season. The leaves are small and oval-shaped. Despite it being a deciduous shrub, some leaves will persist throughout the winter.

The berries are eaten by several bird species. I once saw three birds – an American Robin, Spotted Towhee and a Dark-eyed Junco – all amicably sharing the attractive berries in one shrub.  Raccoons, chipmunks and deer mice also eat the berries and deer browse the foliage.

Red huckleberry can thrive in a variety of conditions, from sun to full shade. It does well in acidic soils, and often a shrub will grow from a nurse log or at the top of a stump.

The greenish twigs help jumpstart photosynthesis in late winter. This is critical for a small-leaved shrub growing in shade.

Look for red huckleberry in any local forest type. The tart berries are an acquired taste for humans – I only eat a few a year, preferring to leave them to be ingested by birds which will help to scatter the seeds.

Green twigs, small delicate leaves that turn reddish in the fall, and attractive berries make this shrub a bright star in our shadowy forests.

Cedar Waxwing by Martha Ellis.

Fauna: Cedar Waxwing (Bombycilla cedrorum)

Who can describe a Cedar Waxwing without using the word elegant? Not only are they one of the most attractive bird species, but they’re also responsible for “planting” many trees and shrubs.

Waxwings get their name from the bright red waxy substance found on the tips of their secondaries, those wing feathers found closest to the bird’s body. The more tips that are red, the older the bird.

Cedar Waxwings are 7 inches in length and have a wingspan of 12 inches. The face has a black mask edged in white. The head has a prominent rear-pointing brown crest that gives them – well – an elegant appearance. Light brown is also the color of the back and wings, while the undersides are yellowish. The tail tip is bright yellow.

Nesting for this species is later than in most songbird species. The female chooses a site and make nest-building motions. She’ll go on to do most of the construction and all the incubating. Her mate will guard the site and feed her while she’s on the nest.

Younger birds, those with fewer waxy tips on their wings, choose mates from their generation. Not surprisingly, older and more experienced individuals have a higher breeding success rate.

In spring, waxwings eat flying insects. They also include flower buds and petals at this time.

As summer progresses, they switch to a menu that includes fruit. Favorites are red-flowering currants, twinberries, bitter cherries and serviceberries. For the most part, waxwings avoid spending time deep in forests, but I’ve seen them make an exception when red huckleberries ripen.

If there is fruit available in fall and winter, then waxwings don’t find it necessary to migrate. When those crops fail, these birds will wing southward to winter in Mexico and Central America. The planting of non-native fruit-bearing trees and shrubs has increased the number of these attractive birds willing to spend winters in the north.

Read more Habitchat blog posts