Despite the fact that Tree Swallows (Tachycineta bicolor) are not uncommon on southern Vancouver Island we only have a single record of this species at Leaning Oaks, a pair of birds on migration in April. It is very likely we have overlooked "fly over" Tree Swallows. Like the much commoner Violet-green Swallow, Tree Swallows are cavity nesters, using woodpecker holes, rotted cavities in trees and nest boxed to raise their families. Here on southern Vancouver Island they are more closely associated with water than Violet-green Swallows, which uses a wider variety of habitats.
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California Quail (Callipepla californica) are noisy, visible parts of the avifauna of Leaning Oaks. We have several pairs using the property this breeding season. Some years they disappear for the winter months, and some years we have large groups visiting the bird feeders throughout the year. They almost always successfully hatch chicks here, but some years the chicks succumb to wet weather and other years they are preyed on extensively by Cooper's Hawks. California Quail are introduced species here, brought onto Vancouver Island as a game bird. Chipping Sparrows (Spizella passerina ) are the smallest sparrows that visit Leaning Oaks. They are uncommon summer visitors here, and to our knowledge have not bred on our property, although we have seen newly fledged young very close by. This year provided our earliest spring record, with a pair on the lawn eating dandelion seeds on 23 April. Our latest record in the year is the 2oth of July, so they don't linger here very long. I have spent a lot of time listening to recordings and searching for calling Chipping Sparrows, some of which sound an awful lot like (some) Dark-eyed Juncos. Despite diligent study, I still make mistakes and feel far more sure of an identification when I see the bird involved. Small, dapper and pale with a bright rufous cap, they don't look anything like a junco - fortunately. Yellow-rumped Warblers are found here at Leaning Oaks in the spring and early summer and then essentially disappear for a month and then make an appearance on fall migration from mid-August until the end of September. They may well be here, only silent in the canopies of the Douglas-fir or perhaps they move up in elevation during those months. The Yellow-rumped Warbler has two distinct colour forms that used to be considered separate species: the "Myrtle" Warbler of the east and "Audubon’s" Warbler of the mountainous West. The Audubon’s has a yellow throat; in the Myrtle subspecies the throat is white. Female Audubon's have less boldly marked faces, lacking the dark ear patches of the "Myrtle" Warbler. We get both forms on migration, but the form that lingers here to breed is the "Audubon's" form. Most years, Red-breasted Sapsucker (Sphyrapicus ruber) is an occasional visitor to Leaning Oaks, but a few times over the years this species has been on the property for extended periods and over the breeding season. Sapsuckers (there are 4 species in BC) feed on tree sap that they harvest by drilling net arrays of holes through the bark and into the cambium of a tree. Here the tree of choice is Douglas-fir and one of our trees has an large area of sapsucker wells on the trunk about 8 m off the ground. The sap attracts insects, which are also used as food by the sapsucker. Some winters, especially those with pronounced cold snaps, we have an influx of Red-breasted Sapsuckers. Sigh, maybe next pond will be this big! It would have to be big to hold the world's largest waterfowl. Beginning about mid November through to March or April we see or hear these bulky beautiful swans flying over Leaning Oaks on their way to or from a local wetland or field where they over winter. The trumpeting call is a wonderful reminder of how sometimes there really is good news and conservation success stories. By the early 1900s Trumpeter Swans (Cygnus buccinator) had been harvested to near extinction. In 1932 only 69 were known to exist! In the early '50s a few thousand were found in Alaska. And as you can see by the graph from the Pacific Flyway Council (2006) just the coastal population was 25 000 by 2005! There are still concerns about fragmentation of wintering habitat and development around their breeding grounds in the north - but they are doing alright now, with populations that continue to increase. It is hard to imagine Leaning Oaks without Anna's Hummingbirds (Calypte anna), they are nearly ever -present with their songs that sound like radio static, the small squeak notes that the males give during courtship flights and the constant buzz of activity around the feeders and flowers in the garden. When we first moved here however, Anna's Hummingbird had not yet colonized the property and I can still remember seeing the first one in the garden on a sunny October afternoon. Local researchers and naturalists, many of them associated with Rocky Point Bird Observatory, have located nests, followed successes and banded Anna's Hummingbirds and are slowly learning about the remarkable lives of this species. Anna's Hummingbird probably arrived on southern Vancouver Island in the 1950's. The species breeds nearly year round, with some females building multiple nests a year here. They sometimes will reuse a nest, or even a one of a Rufous Hummingbird and they will often re-use nesting material - sometimes while the chicks are still in the nest! Alison Moran from the RPBO hummingbird project tells of a female that had overlapping nests where the nest material was reused this way for four successive nestings. Golden-crowned Sparrows (Zonotrichia atricapilla) are mainly spring and fall migrants at Leaning Oaks, although elsewhere on southern Vancouver Island they are common throughout the winter months, and have, very rarely, lingered and bred. They are mostly skulkers, hiding in thickets and hedgerows, coming into the open to feed on seeds in the ground or in low weeds. In fall when they arrive they often sing, a mournful clear song that can be remembered as "Oh dear me" or "I'm so weary" which is the source of another common name "Weary Willie". Turkey Vultures (Cathartes aura) are a common sight here during the summer and fall months. Almost always seen flying over Leaning Oaks with wings outstretched and tipped upwards, they have a distinctive rocking back and forth as they fly. They are most noticeable on nice days when they stay aloft on thermal uprisings. They also seem to appreciate the assist of a good wind storm as well, and we see Turkey Vultures using high winds to keep themselves aloft with little or no apparent effort on their part. Here we have Turkey Vulture records from the third week of February to the middle of November. They are clearly increasing in numbers as well as how long they stay, with small numbers being found year round on southern Vancouver Island now. It is suspected they have been assisted with a contant supply of road-killed animals on ever busier road and milder winters.. Amongst local birders there is a running joke that if you hear a bird noise that you don't know - it is a Bewick's Wren (Thryomanes bewickii). Males have multiple songs that they can sing (from half a dozen to almost 2 dozen depending on the male), and there is considerable local geographical variation on top of that. Throw in a few chucks, whistles, burrs and trills and you get a lot of variety. Click here to listen to Bewick's Wren vocalizations from througout their range. They often nesting in human made things like mailboxes, shoes, hats, nest boxes and other cavities. Loud and visible, Bewick's Wrens are often hard to ignore neighbours. They are present at Leaning Oaks from time to time and have raised families here, but we also have had them disappear for months at a time some years, particularly after period of cold weather. Of our 3 wrens it is the longest tailed and has a distinctive white eyebrow stripe. |
AuthorsTwo biologists on a beautiful property armed with cameras, smart phones and a marginal knowledge of websites took up the challenge of documenting one species a day on that property. Join along! Posts and photographs by Leah Ramsay and David Fraser (unless otherwise stated); started January 1, 2014. Categories
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