Tuesday, January 27, 2015


For a unique and intimate experience with waterfowl and other birds, visit George C. Reifel Migratory Bird Sanctuary west of Ladner, British Columbia.

Reifel Refuge, as it’s called by many, is a 300-hectare (740-acre) plot of land on Westham Island on the Fraser River, about an hour’s drive from the metropolis of Vancouver. George Reifel bought the land in 1927 and established a family recreational retreat on it, creating waterfowl habitats as well as road access by a series of dikes and causeways.

In the 1960s, the Reifel family granted a lease to the British Columbia Waterfowl Society to create a bird sanctuary on the land. Helped by the management of Ducks Unlimited Canada, wildlife habitat was preserved and expanded with the provincial government establishing a game reserve on adjacent land. In 1972, the family further donated and sold the land to the federal government on the condition that it would be maintained as a sanctuary.

The government designated part of the sanctuary and the area adjacent to it, some 328 hectares, as the Alaksen National Wildlife Area. Some activities are permitted on this land but not the free access to the public that characterizes the sanctuary.

The sanctuary charges a nominal entrance fee and is open from 9 am to 4 pm every day. Sometimes it has quite large crowds, not a place to go if you want to get away from people for your nature experience. However, the high density of humans day after day is what has conditioned the birds to be as unafraid of us as they are.

The sanctuary was set up for waterfowl, and there is always a good representation of local waterfowl species, both dabbling and diving ducks. Large numbers of Snow Geese migrate through the adjacent wetlands, some of them remaining for the winter, and mostly those will be seen overhead moving between feeding areas. All the ducks present are somewhat used to people and will furnish close viewing and great photo opportunities.

There is a small population of resident Sandhill Cranes, most of them not pinioned, and some of them will feed from the hand. Some of them are good at gently taking seeds from an open palm, but be aware that you’re taking the chance of a poke with a sharp beak from those that aren’t. There are also Black-crowned Night-Herons roosting near the entrance to provide good looks at another unexpected species.
There are feeding stations everywhere, and during the winter they attract great numbers of seed-eating birds, for example Black-capped Chickadees, Red-winged Blackbirds, Spotted Towhees, Fox, Song, and Golden-crowned Sparrows, House Finches and House Sparrows. The chickadees are so tame that anywhere along the trails they will land on your hand if you open it with sunflower seeds on it. Occasionally a Red-breasted Nuthatch may do the same.

Brown Creepers and kinglets are also often seen, and like other birds there are quite tame. Quite a few other passerines inhabit the patches of woodland, and unusual visitors are seen with some regularity, for example Bohemian Waxwings and Pine Grosbeaks recently. And it’s always worth watching for less common sparrows such as Swamp, Harris’s, and White-throated along the path.

Because of all the feeders and seeds, rats and mice and Eastern Gray Squirrels (including the black morph, established in the Vancouver area) are also attracted to the area, and the local owls know it. A pair of Great Horned Owls is regularly seen, and there are always Northern Saw-whet Owls present, if very hard to see in the dense foliage where they roost. Other species of owls are seen from time to time, and there are usually hawks and falcons about, interested in the songbirds as well as the rodents.

You can buy sunflower seeds at the office and carry them around to feed to whichever birds you like. You may give them all to chickadees, as there is something wonderful about one of these tiny birds landing on your hand. You may be attacked by Mallards before you barely get going onto the trail, and Mallards are the most abundant and insistent ducks in the place. But look closely, and among the Mallards there will be at least a few American Wigeons and a few Northern Pintails.

More than these, there are Wood Ducks scattered around the area, and they too are interested in handouts if they can get to them before the omnipresent Mallards. They are shy enough that you’ll have to seek them out, but one way to feed them is to put seeds on top of fence posts, which the Wood ducks—tree dwellers that they are—can easily get to. Of course they have to beat the chickadees and Song Sparrows to them.

Dennis Paulson

Thursday, January 22, 2015


North America has the distinction of being the only continent on which a group of birds has evolved the ability to tap into the sap of living trees. These are the four species of sapsuckers (Sphyrapicus): Yellow-bellied (S. varius), Red-naped (S. nuchalis), Red-breasted (S. ruber) and Williamson’s (S. thyroideus). The first three replace one another from east to west across North America, while Williamson’s occurs with both Red-naped and Red-breasted in the West.

Sap flows through the xylem and phloem of a tree with a function rather similar to that of blood in animals. It’s not important in respiration, as it is in us, but nutrients and other chemicals circulate in it. It is full of sugars, presumably an important component of its nutritive value. Phloem sap of deciduous trees can contain concentrations of greater than 25% sugars in summer.

Sapsuckers dig holes in the bark of trees to get at this sap. They dig phloem holes, usually square and shallow, and continue to enlarge and add to these holes, excavating new ones above the old in a vertical arrangement. They also dig xylem holes, smaller and usually circular and penetrating the cambium layer to reach the xylem. These are arranged in horizontal rows. Some trees show both types of holes, easily distinguished.

As soon as these holes are dug, sap begins to flow into them, and they can then be considered sap wells. They continue to flow while temperatures are sufficiently high, but when air temperatures drop below freezing, the sap freezes in the wells and is then inaccessible to the sapsuckers. This is why sapsuckers are the most highly migratory of woodpeckers. As temperatures drop during the winter, many Red-breasted Sapsuckers, normally nonmigratory, descend from the mountains to appear in Pacific Northwest lowlands in numbers.

Sapsuckers may spend over half of their foraging time constructing and maintaining their sap wells. They seem to prefer tree species with higher sucrose content in the sap rather than those in which flow rates are higher. However, their wells have been found in about 1,000 species of woody plants, native and introduced.

They also feed on insects attracted to or trapped in the sap as well as additional arthropods captured on the bark or in the air. They also take some fruit and leaf buds. Insects are captured to feed the young, but the adults often stop at sap wells and dip the insects in sap before taking them to the nest. This may be for added nutritional value or to acclimatize the young to feeding on sap.

Numerous other species find these sap wells nutritious, including both birds and mammals. In the Pacific Northwest, species that I have seen coming to the wells include Anna’s and Rufous Hummingbirds, Downy Woodpeckers, Black-capped Chickadees, Ruby-crowned Kinglets, and Eastern Gray Squirrels. The wells may be especially important to hummingbirds, some of which actually follow individual sapsuckers to note the distribution of their wells. Sapsuckers actively defend their wells against some of these species, but each sapsucker has so many wells that this isn’t a very productive tactic.

The fact that there aren’t any sapsucking woodpeckers in the temperate forests of Eurasia is an elegant example of the idea that not all niches are filled. But of course sapsucking insects of the order Hemiptera (true bugs, aphids and their relatives) are everywhere in the world.

Dennis Paulson