Selected Excerpts from the Vancouver Natural History Society “Bulletin”
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- Editorial – The Game of the Name
- End Note 32: Birds for the Record (see page 277) Ornithology
- End Note 33: Christmas Bird Count Wing-tagged Gulls (see pages 277-278) Crescent Beach – The Place of Birds
- Seed Plants, mainly from the Shulaps Camp
- End note 34: V.N.H.S Membership Cards to Gain admittance to the Museum (see page 278)
- End Note 36: The Name Game (see page279) Nest Records, Pesticides and You
- End note 37: Birds for the Record (see pages 279-280) Bird Chatter
- Vancouver Christmas Bird Count 1969
- Burnaby Lake Wildlife – Habitat or Epitaph
| Part I
When the white man first visited the climax-forested shores of Burnaby Lake water birds, especially ducks and geese, were abundant. George Green, a pioneer resident of Burnaby, wrote in his book History of Burnaby, “Waterfowl in myriads swam on the tranquil bosom of the Lake and slept peacefully in the covert of the reeds beside the shore. Blue grouse and willow [ruffed] grouse in goodly numbers rested at noonday amid the stately firs of the forest, and the whirr of their vibrant wings often awoke my silent solitude as they sped down the shaded and quiet aisles of the well carpeted woods.” So attractive was Burnaby Lake with its mature green forests, crystal clear waters and carefree wildlife that in the summer of 1859 a “pleasure path” was cut from the newborn City of New Westminster to the lower end of the Lake. This woodland paradise wasn’t to last however, for with the white man came the pioneer tools of the lumber industry. Soon the land was altered for man’s use and as a result wildlife began to disappear from the Lake. Fortunately early conservationists noticed this disappearance and brought it to the attention of the then B.C. Game Commission. On September 12th, 1924 Burnaby Lake was formally designated a Game Reserve. Once again the Lake afforded sanctuary to its abundant waterfowl populations. Gradually, during the next forty years, the area around Burnaby Lake became residential. For this reason the Lake was difficult to access, and because it was illegal to shoot in the Municipality, regular checks by Game [Commission] authorities were difficult and somewhat unnecessary; Burnaby Lake was declassified as a Game Reserve on August 10th, 1964. Today, Burnaby Municipal Council is responsible for determining a policy for the Lake. Burnaby Lake has been receiving small amounts of pollutants, mainly from industrial wastes, for nearly a decade. The deplorable decrease in the Lake’s aquatic life bears witness to this. I have watched the Pacific terrapin, unique to Burnaby Lake; sun itself on the banks of Eagle Creek. The last terrapin I saw was in 1959. The industrious muskrat, once abundant, is now uncommon and forced to homestead along the banks of the Brunette River that drains the Lake. All fish but the hardy three-spine stickleback have disappeared. Even the giant bullfrog once caught on red cloth-baited hooks and sold to local Orientals for 25c, are now rare. Waterfowl, however, are still abundant and varied. Through the combined efforts of the Canadian Wildlife Service, B.C. Waterfowl Society and other interested parties, this excellent waterfowl habitat, on the verge of destruction, can possibly be saved. During the past six years a comprehensive biological survey with emphasis on waterfowl, has been carried out on Burnaby Lake by the B.C. Waterfowl Society and members of the Vancouver Natural History Society. From field notes, it has been verified that 26 kinds of waterfowl are still attracted to the Lake. These species include the whistling [tundra] swan, [greater] white-fronted goose, gadwall, blue-winged and cinnamon teal, ring-necked duck, canvasback, ruddy duck, hooded and red-breasted merganser and many others. This attraction is understandable because the Lake provides the five fundamental requirements for waterfowl. In importance these are: 1. An adequate food supply throughout the year. Ecologically, Burnaby Lake is referred to as an eutrophic lake. This type of lake is characterized by abundant shoreline vegetation, dense planktonic populations with seasonal ‘blooms’ and shallow water. Burnaby Lake is shallow, to eight feet in depth with abundant aquatic invertebrate life populations. Planktonic ‘blooms’ occur in late spring and fall and so abundant are the minute animals during these periods that one resident near the lake actually strains the animals from the water for use as fertilizer on his potted house plants. Bottom fauna which denotes animal life found in the muddy bottom of the Lake, such as chironomid larvae, worms [?], dragonfly nymphs and other species of insect life, is abundant and readily obtained by the sieves, especially that of the [northern] shoveler. Seeds of aquatic plant food like the duckweed, pondweed, coontail and pond [water] lilies are used by many waterfowl. During severe winters the Lake may be frozen but with the slightest thaw, the birds return to feed. 2 Adequate cover during migration and especially during the breeding season. The shores of Burnaby Lake are marked completely by a mixed band, varying in width, of cattail and bulrush. At each end of the Lake this band broadens out to form two large dense marshy areas. This vegetation provides protection and cover for the birds throughout the year. During the breeding season the Lake surface is almost entirely choked by aquatic plant growth, especially the yellow (native)[pond-lily] and white (introduced) water lily. Shelter, protection and food are thus provided for the eight species of waterfowl known to breed on the Lake. Any future development plans should include the opening up of large areas of the vegetation to form clear potholes for feeding and resting. 3 A stable water level, especially during the breeding season. This has been a problem in the past but thanks to talks between Mr. R.D. Harris, Canadian Wildlife Service and Mr. Bunnell of the Greater Vancouver and District Sewage Board, a relatively stable water level is now maintained throughout the year. 4.A number of resting and loafing bars for use during migration. These are not abundant and future management should include more of them. The bars could be formed by using lake sediment dredged to open the areas of water lilies. 5. Freedom from disturbance. This is not a major problem yet; however if motor boating of any description is permitted as has been suggested by various individuals, waterfowl will undoubtedly disappear. A classic local example of waterfowl habitat destruction by motor boating is Hatzic Lake near Mission. Wayne Campbell (Part II will be printed in a later issue of the Bulletin) #145 December 1969 Editorial – The Game of the Name It has been suggested for some considerable time that the Bulletin should have a name, growing as it has in size and content from a simple sheet for the announcement of coming events, to its present dimensions. It becomes necessary that our little quarterly organ should acquire a name by which it can be recognized so that official records of bird, animal and insect sightings and plant occurrences may be published in it and come promptly and in proper form to the notice of those who matter most in such pursuits. Most of our Bulletin’s sister publications across Canada have been endowed with the name of some bird, animal or plant characteristic of the area in which the publishing organization operates. No blinding flash of inspiration having fulminated among the members of your Executive, it has been decided to throw the matter open to competition among the membership. A sub-committee will judge the entries and a prize will be awarded to the author of the selected name. The name should be short, pithy, preferably single-worded, and above all should be immediately suggestive of nature in our Vancouver environment. Not necessarily the name of a bird, animal or plant, though these often seem appropriate. It might be suggestive of stretches of our tidal water: “Trash” or perhaps “Oilslick”. Or our prevailing climate might be immortalized in a name such as “Downpour”. Your Editor doubts that any of the above names will be chosen and, in any event, the Editor is not eligible to compete. Write your proposed name and a brief line saying why you feel your choice to be appropriate. Only one name suggestion per entry, but a member may make more than one entry. Contest closes January 31, 1970. End Note #32: Birds for the Record (see page 277) Ornithology Bird Chatter – The Checklist of Vancouver Birds (1969 Edition) has been published and is available through our Society at 10c per list or 12 for $1.00. Lists can also be obtained from the Centennial Museum, the Vancouver Public Aquarium and the George C. Reifel Waterfowl Refuge. The list is useful for day trips and can be used to keep annual and life lists seen in the area. Have you heard of Dab Chicks? Barbara Howie, while on vacation near Bamfield this summer, was told by a fisherman that the little brown seabirds offshore were called Dab Chicks. Barbara says they were marbled murrelets. Anyway, in Britain a Dab Chick is a Least Grebe! Philadelphia vireos, Kentucky warblers and northern waterthrush are showing up on the northern California coast this year. Ornithologists at Point Reyes Bird Observatory speculate that the “foreigners”, some thousands of miles from their [usual] migration paths, could have suffered recent upsets in their hereditary mechanisms that control bird migration. Look closely at gulls on lawns in the Lower Mainland. A bright white gull may turn out to be a snow goose. Several birders have reported seeing them feeding on lawns in Vancouver this fall. “The golden-cheeked warbler” says Time magazine, “may be just a footnote in an ornithology textbook, another species that fails to adapt to man.” This warbler, native only to Texas, may lose one of its last nesting grounds in Meridian State Park to a proposed nine-hole golf course. Kay Smith reports that an albino Steller’s jay was at the Barnes’ house in West Vancouver in late October. Wayne Weber is 95 per cent certain he saw a Ross’s gull near the cannery at Point Roberts in early October. Birders [going] to Point Roberts keep your eyes open for a small, pink-breasted gull with a wedge-shaped tail. End Note #33: Christmas Bird Count & Wing-tagged Gulls (see pages 277-278) Crescent Beach – The Place of Birds Let us look to the Earth to its wealth and beauty, and be proud that we are part of it. Let us respect it, and time and space, the forces of creation and life itself. As we hold the future in our hands, let us not destroy it. Helen Hoover. The Long-shadowed Forest It could be said that bird study at Crescent Beach began some 145 years ago when on Monday, December 13th, 1824, a small party of explorers led by Chief Factor MacMillan of the Hudson Bay Company made their way down the Nicomekl River where they reported seeing “immense flocks of plover” at its estuary.
of standing room only! These same mud flats are an attraction for a variety of shorebirds that have included on rare occasions, American golden plovers, sandhill cranes and long-billed curlews. Land birds are well represented and some bird students have been rewarded by the sight of a Lewis’s woodpecker, Lapland longspur and snow bunting. The total number of all species stands at 167. I have no doubt that the once beautiful Crescent Beach that Canon Holdom loved so well will be completely destroyed. One only has to witness the acres of trash left by ephemeral users such as weekend picnickers or the abandoned car bodies left to rot near the beach. Crescent Beach – meum et tuum! Al Grass Crescent Beach lies in the Municipality of Surry near the resort City of White Rock Botany Section “Arctic lupines bloom after 10,000 years” – Dr. Michael Black, New Scientist, October 19, 1967. Seeing the Arctic lupine, Lupinus arcticus in profusion in the Shulaps at our V.N.H.S. Camp last summer, reminded me of the above-noted article that I had read. Extracts of interest follow: “During mining operations at Miller Creek, Yukon Territory, in July 1954, a mining engineer, Mr. Harold Schmidt, discovered a system of burrows made by rodents in the frozen silt. These burrows, 3 to 6 meters below the surface of the silt which itself was 8 to 12 metres thick, were excellently preserved. They contained skulls and skeletons of the rodents, later identified as the collared lemming, and a number of seeds, probably originally set down as a food store.” The seeds attracted little attention but were kept for 12 years, fortunately under dry conditions, before being handed over to a staff member at the National Museum of Canada on his visit to the area. On reaching the authors of the science article (Vol. 158. p.113), the two dozen seeds in the sample were readily identified as being those of the Arctic lupine. When tested, 6 of the seeds germinated after 48 hours on wet filter paper and have produced normal plants. One of the plants has even developed flowers. Rodent burrows have previously been found in the frozen organic silt, laid down in the late Pleistocene age (10,000 – 200,000 years ago). By carbon-14 dating the animal remains were estimated to be around 15,000 years old. The collared lemming whose remains were found with the seeds is a species of the Arctic and high alpine tundra and so we must suppose that they left Miller Creek during the time when the area first experienced the post-glacial warming which occurred about 10,000 years ago. The seeds of the Arctic lupine, then, are at least 10,000 years old and survived against unlikely odds. That they were able to do so, and to produce healthy plants, is a striking example of the remarkable property of the cells of some plant organs to remain alive in a dry, seemingly dead state for so long. Stan C. Roberts Coordinator, Botany Section. Seed Plants, mainly from the Shulaps Camp Camp 1969 was not in a park so we were free to collect samples of all the plants we saw. Display facilities at the Shulaps camp were good and the collection just grew and grew as the field trippers brought in new treasures. As usual, identification was an educated guessing game without benefit of equipment or the best reference books. However, most of the specimens came home so most of the doubtful names have been confirmed or corrected. Specimens from the Tchaikazan Valley are still not all identified. Four of our plants were of particular interest, three from the Shulaps and the fourth from Tchaikazan. Most of the party had not before seen “dusty maidens” [hoary false yarrow] the beautiful small pink relative of a gray-white weedy plant that grows around Princeton. [Editor’s note: “dusty maiden” is but the alpine form of Chaenactis douglasii]. I have seen the pretty species only in the Elizabeth Mine vicinity but it grows further south and in the Rockies. The sword fern [Kruckberg’s holly fern] Polystichum kruckebergii is named for Dr. Kruckeberg of the University of Washington in Seattle. Until a few years ago it was called, doubtfully, a form of Polystichum scopulinum, but now it has been established as a separate species by Dr. Wagner, a fern specialist in Michigan. In his study Dr. Wagner used the U.B.C. specimens, among others, that were collected at Elizabeth Mine in 1961. (I might add that he still has those specimens and I’m beginning to fear, on permanent loan.) Cheilanthes siliquosa [Aspidotis densa, slender lip fern], Indian’s dream (don’t ask me who came up with that common name but it has a pleasant sound) was in the crevices of an old rockslide. This is apparently a typical niche for it if the rock is calcareous, but I can find B.C. records of it only from the extreme south. I am sending pictures and notes to Dr. T.M.C. Taylor in Victoria for comment and confirmation of the identity. Erigeron pallens [purple daisy], a tiny fleabane, in size and hairiness rather like E. humilis [Arctic daisy] of the Shulaps area, was found at the head of the Tchaikazan Valley. It is known in the Rockies but is rare enough there that it is on the restricted list even for people granted a collecting permit for the parks. We saw it when we camped in Larch Valley. The list from the Shulaps Camp follows. Unfortunately it is not complete even for what we saw, but it does show what can be found by close inspection even when the country looks at a distance to be exceedingly barren. Common Name Botanical Name Comment [scrub] birch Betula glandulosa [nana] not B. pumila [Boreal] sandwort (Arenaria)[Minuartia] rubella small cushion [thread-leaved sandwort] Arenaria capillaris small A. Formosa [Bering] chickweed Cerastium beeringianum not C. Alpinum moss campion Silene acaulis strawberry-blight Chenopodium capitatum yarrow Achillea millefolium false dandelion [orange agoseris] Agoseris aurantiaca [short-beaked agoseris] Agoseris glauca [racemose] pussytoes Antennaria racemosa & other Antennaria. spp. heart-leaved arnica Arnica cordifolia
[northern wormwood] Artemisia campestris var. [?] An alpine variety [leafy] aster Aster foliaceus [Arctic aster] Aster sibiricus dusty maiden [hoary false yarrow] Chaenactis (alpina) douglasii edible thistle Cirsium edule fleabane [subalpine daisy] Erigeron peregrinus [arctic daisy] E. humilis very small & hairy [Lyall’s golden weed] Haplopappus [Tonestus] lyallii not H. bradegei [slender] hawkweed Hieracium gracile groundsel or ragwort [arrow-leaved butterweed] Senecio triangularis [dwarf mountain butterweed] Senecio fremontii [western groundsel] Senecio integerrimus [woolly groundsel] Senecio canus alpine [northern] goldenrod Solidago multriadiata [horned] dandelion Taraxacum [ceratophorum] native, not weedy [worm-leaved] stonecrop Sedum stenopetalum silverberry [wolf-willow] Elaeagnus commutata soopolallie Shepherdia canadensis crowberry Empetrum nigrum false heather [pink mountain-heather] Phyllodoce empetriformis [yellow mountain-heather] P. glanduliflora [hybrid mountain-heather] P.x intermedia hybrid of the two preceding [four-angled mountain-heather] moss heather Cassiope tetragona No specimens of C. mertensiana mountain misery or white [-flowered] rhododendron Rhododendron albiflorum bearberry or kinnikinnick Arctostaphylos uva-ursi bog-laurel Kalmia polifolia [microphylla] [four]-parted gentian Gentiana [Gentianella] propinqua closes at a touch [northern gentian] Gentiana [Gentianella] amarella mountain [silky] phacelia Phacelia sericea [Arctic] lupine Lupinus arcticus [dwarf mountain lupine] Lupinus lyallii [mountain] locoweed Oxytropis gracilis [monticola] alpine milk-vetch Astragalus alpinus [common] butterwort Pinguicula vulgaris sticky-slimy leaves digest insects nodding onion Allium cernuum false [Indian] hellebore Veratrum eschscholtzii [viride] Columbia [tiger] lily Lilium columbianum [common] false asphodel Tofieldia pusilla not T. glutinosa broad-leaved willowherb Epilobium latifolium fireweed relative [alpine willowherb] Epilobium alpinum vars. tiny fireweeds [Note – original E. alpinum has been split into a number of species. See “Flora of B.C.” Vol. 3, P.352 –366] white rein-orchid Habenaria [Platanthera] dilatata [showy] Jacob’s ladder Polemonium pulcherrimum knotweed or [alpine] bistort Polygonum vivparum bulblets among flowers [sheep] sorrel Rumex acetosella a naturalized weed mountain sorrel Oxyria digyna
[sulphur buckwheat] Eriogonum umbellatum [sulphur buckwheat] Eriogonum umbellatum relative of sorrels and knotweeds windflower [northern anemone] Anemone parviflora Arctic raspberry [nagoonberry] Rubus arcticus [villous] cinquefoil Potentilla villosa [diverse-leaved] cinquefoil Potentilla diversifolia [snow cinquefoil] P. quinquefolia [nivea] [white] mountain avens Dryas octopetala var. hookeriana sometimes classified as D.hookeriana [five-stamened] mitrewort Mitella pentandra [fringed] grass-of-parnassus Parnassia fimbriata fringed on petals, no leaf on flower stem [Kotzebue’s grass-of-parnassus] Parnassia kotzebuei [Lyall’s] saxifrage Saxifraga lyallii [tufted saxifrage] Saxifraga caespitosa [spotted saxifrage] Saxifraga bronchialis [Langsdorf’s] lousewort Pedicularis langsdorfii wood betony [bracted lousewort] Pedicularis bracteosa beardtongue [small-flowered penstemon] Penstemon procerus Indian [scarlet] paintbrush Castilleja miniata veronica [Alpine speedwell] Veronica wormskjoldii cow-parsnip Heracleum lanatum sweet [sitka] valerian Valeriana sitchensis dwarf [snow] willow Salix nivalis and other species rush Luzula sp. No one saved the names or plants grasses (numerous species) from Dr. Brink’s collection sword fern [Kruckeberg’s holly fern] Polystichum kruckebergii Indian’s dream [slender lip fern] Cheilanthes siliquosa [Aspidotis densa] rock brake or parsley fern Cryptogramma crispa [acrostichoides] [common] juniper Juniperus communis [sub]alpine fir Abes lasiocarpa Engelmann spruce Picea engelmannii whitebark pine Pinus albicaulis
At the Portage Mountain Dam visitors’ platform there is a plaque commemorating the ancient wanderings of dinosaurs. Their footprints, well preserved in the Dunlevy sandstone formation were discovered during powerhouse construction. The plaque first states that the prints are 100 million years old. Then it goes on to say that they were made in the Aptian age, Lower Cretaceous period, of the Mesozoic era. Thus the point of time when these great animals wandered around the sand at this locality is represented in two ways: (1) absolute age in years before the present, and (2) a position on the Geological Time Table. Why two methods of denoting past time? And, one might ask, do geologists really know how many years ago this happened? Aristotle long ago observed that the Earth was being shaped by the normal action of natural forces acting slowly over long periods of time. Such wisdom was lost in the darkness of the Middle Ages and the understanding of geology was particularly constrained by a literal interpretation of the writings of Genesis. An all time low point of knowledge of geologic time was expressed by the pronouncement early in the 17th century by Bishop Usher that the Earth was created catastrophically in the year 4004 B.C. In the 18th century it became apparent to geologists that the physical form and structure of the Earth’s outer layer developed slowly by the very processes that they were observing, and not by catastrophic happenings. They found that shallow seas had once overlapped many land areas; that sediments worn by rivers from the lands were transported and deposited in the seas; that these sediments hardened into rock; and that they became elevated into new land masses. Erosion again reduced the land to sediments that were deposited in new seas, hardened into rock and elevated into new land. Dozens of such cycles were recognized, one upon the other, extending indefinitely back into time. In the words of James Hutton, “there was no evidence of a beginning, no prospect of an end.” In the background of this majestic cycling of sea and land there was a continuous process marking the passage of time. This was the evolving development of organic life, spreading world-wide through the seas, and leaving its imprint as fossil remains in the sedimentary rocks. Fossils provided a means of relating in time and on a world basis, the sedimentary rocks and the processes that produced them. The degree of evolution of the fossils provided a basis for assigning relative ages to the rocks. Geologists were thus able to construct a detailed record of the events of Earth history, the familiar Geological Time Table, with its divisions into Eras, periods and Ages. Greatly unknown and unappreciated, the Table, with its record of organic evolution is truly one of man’s great accomplishments. The Table had several shortcomings. Many rock formations, recording some important events, are produced by heat and so they bear no fossil records. Much of geology took place long before life had evolved to the point where fossils were produced. Its most serious shortcoming was that it possessed no scale of absolute time. It was a story rich in detail with section and chapter headings all assigned, but laid out as on a galley proof, without page numbers. This was the way things stood at the end of the 19th century. The story of how the Table was time-calibrated in the 20th century we’ll leave to another Bulletin issue. C. S. Ney What is a Barnacle? Barnacles: -Phylum arthropoda; Order: - Cirripedia. There are about 400 species of barnacles in the world. What is a barnacle? It is a crustacean, a relative of the crab, lobster, shrimp and sand flea, etc., that has attached itself permanently to some object larger than itself. A shell has developed in which it lives and its legs have become modified into most efficient sweeps for the capture of the small sea creatures and organic material on which it feeds. The opening of the shell is closed by four movable cover plates, hinged like folding doors. When these are opened the legs (Cirri) may be protruded and when they are closed the barnacle is protected from enemies and from drying when exposed to the air. Some barnacles have chosen strange placed in which to live. The acorn barnacles fasten directly to a rock or shell, a piece of wood or kelp or the carapace of a crab, and prefer to live in more sheltered waters. One species of barnacle is found only on the tongue of a certain turtle. Another bores holes in soft rocks. Several species are found only in deep water. Others are found only in inter-tidal areas. Goose barnacles like the strong wave action of our open ocean coastline. Certain Sessile barnacles are found on whales and these are known by the general term of “whale barnacle”. Some species of Cirripeds are parasitic on other crustaceans. One that has this habit loses all trace of resemblance to its relatives and becomes a mere sac with a system of branching roots that reach throughout the body of the host. There are two divisions of barnacles, the Acorn, or Sessile [barnacles], and the Goose, or Pedunculate [barnacles]. In both divisions the internal anatomy is much the same, but their outside appearance is very different. The Sessile have calcareous shells fixed directly to some support; the Pedunculate have the body chamber on the end of a flexible stem called the Peduncle which may be anchored to a fixed or floating object, or to a float produced by the cement gland. Most barnacles are hermaphroditic, that is both male and female reproductive organs are present in each individual. Ovaries are located below the mantle cavity. A pair of oviducts open into the mantle cavity on each side of the head. In all species the eggs are retained in two sacs in which they are held together in layers by a delicate transparent membrane. The young barnacle leaves the mantle cavity of the parent as a free swimming Nauplius. This larva increases in size by a series of molts until it reaches the Metanauplius stage during which it changes in form and the single eye becomes two. By the end of the next molt a bivalve shell has developed, additional appendages appear, and the globules of fat form in the body to provide buoyancy. After a period of some days it settles on a solid object to which it becomes attached. The larval bivalve carapace is shed and the shell-like plates begin to form from the outer surface of the mantle. For the rest of its life the barnacle remains fixed in this position literally standing on its head and kicking food into its mouth with its feet. On the B.C. coast there are only two genera of Sessile barnacle – the Balanus and the Thamalus. At intervals throughout life a barnacle casts off its old shell and replaces it with a larger one to allow for growth. For some unknown reason, molting seems to take place simultaneously over a large area. For a few weeks many young periwinkles and mussels live on the empty shells of barnacles. The attachment of barnacles to the bottom of ships is a serious matter and periodic removal from hulls and repainting is necessary. They are considered therefore to be a serious pest in marine circles. On the other hand, the young that are free swimming for some time after they are hatched, are eaten in large quantities by various commercially important fish. C. Gough
End note #34: V.N.H.S Membership Cards to Gain admittance to the Museum (see page 278) #146 March 1970 End Note #35: Lighthouse Park Handbook; Library News & Vancouver Junior Naturalists (see pages 278-279 The Dynamic Spirals of Plants (Excerpt from This Green World by Rutherford Platt) Stand off and look at the crown of a tree. Although the leaves are beautifully massed, they may at first appear to be placed haphazardly. Look again. Stand under the arching limb of a beech or elm or the flat, angular branch of a dogwood. What do you see? A mosaic – one of the wonders of the plant kingdom. Note how this mosaic is placed together, detail-by-detail, throughout the entire pattern of the tree. Think of branches as projecting from a circle made by the cross-section of the tree trunk. If the distance between two successive branches is one-third of the way around the circle, their angle is 120º. As the branches mount the tree they go round and round with equal spacing. One kind of tree may put forth its branches at an angle of 90º, 144º or 180º; whatever the angle of the species, it is constant throughout the tree. These angles made by the branches always divide the circle equally. In mature trees of course, all limbs will not be in place, but that is only because as twigs they were damaged or failed to develop. Their traces would however be there; not one is missed at its true angle. This same angular succession is true of twigs that grow out of a limb. Look still closer and you will see that a leaf emerges from its twig at the same angle from its neighbour as the limbs make with the trunk. In place of twigs and leaves you may see unopened buds, and these two project from the bark in the same succession of angles. Limbs, twigs, leaves, all originate in buds, and these four structures are homologous. Throughout the tree, from the trunk to the tip of every twig, both leaves themselves and the skeleton on which they are hung, are dispersed at equal angles in every direction. At least that is their basic plan although their equal angles may become distorted by later conditions of wind or light. The leaf mosaic is further perfected by the variation of the lengths of branches and the lengths of the stems of individual leaves, so that each leaf may be held away from its neighbour. Often the twigs and the stems of leaves are bent around or twisted to achieve a position more in the clear. The net result is that thousands of leaves can grow together, above and below and around their tree without overlapping or getting in each other’s light. This is functional beauty in one of its purest forms. End Note #36: The Name Game (see page279) Nest Records, Pesticides and You Many of you know that housed in UBC’s Vertebrate Museum is a steadily growing collection of nest record cards. These cards provide standard forms on which naturalists throughout the Pacific Northwest record data on the bird nests they happened to find each year. In 1969 ninety observers sent in 3,510 cards for B.C. alone, bringing the total for the Province up to 26,000 for the 15 years the scheme has been in operation. Across Canada there is growing concern about the effects pesticides may be having on wildlife and there has been an upsurge in interest for nest records that provide a huge sample of data suitable for monitoring clutch size and nesting success over wide areas. If managed properly nest records can function as a warning system. With this object in mind, analysis of common species has begun at UBC in cooperation with the Canadian Wildlife Service. To date barn swallow, song sparrow and starling records have been analysed and we have made a disappointing discovery: - fewer and fewer observers are checking the nests often enough to secure clutch size and nesting success, the very information we need. Ten years ago the record cards in our files were the best in Canada; today they are second worst. If you are concerned about the fate of wildlife in Canada, then become an active contributor to the scheme. Remember, the common species are especially important, yes, even the robin in your backyard! – and you must try to follow through each nest. Only about 6 visits are required. End note #37: Birds for the Record (see pages 279-280) Bird Chatter Important jobs! Scavengers help keep our beaches clean and on January 3rd Penny Haering saw them at work. She watched three northwestern crows and an adult glaucous-winged gull feed on the carcass of a dead female mallard washed ashore at Ambleside Park. Tom Stevens reported a high wire act at Centennial Park. On Jan 2nd he watched three short-eared owls perch with apparent steadiness on telephone wires! During the January snowfall Bill Wilson watched a Lapland longspur visit a backyard feeder at Point Roberts. Vancouver Christmas Bird Count 1969 Date: December 21st, 1969 Time: 12:01 a.m. to 7:30 p.m. Temp: Low 41º - High 48º F. Wind: light, 5–10 Knots. SE Weather: Cloudy with showers, clearing just before noon, then sunny. Visibility: Fair a.m.; excellent p.m. Observers 132 (25 grps) +5 feeder reports. Compiler’s Comments: - This year Vancouver established a Canadian record of 138 species. (Rock dove and blue goose are not included in the report to New York.) Vancouver is probably in the top 25 areas of North America. San Diego and Cocoa Florida usually report over 200 species and several southern states tally around 150. With our 132 participants this year we are in the top five on the continent. An area in southern Florida has recorded a high of 152 participants. The total individual birds we recorded are also a high for Canada. Although the total number of species is not the most important reason for the Count, it is fun to see what each area tallies after a single day in the field. Generally the numbers of birds recorded for each species this year were up. Some birds like the varied thrush and the red-breasted sapsucker, which are forced down to lower elevations by cold weather, were scarce and among the lowest numbers ever recorded on a Vancouver Count Some of our all time highs, like the pied-billed grebe and the ruffed grouse we can attribute to better coverage of areas. Other fluctuations will require closer study. The following are some of the highest or lowest numbers for species in our area. Comparative figures, that is, previous highs or lows, are in brackets. All grebes, with the exception of the eared were highest ever totals: red-necked 107 (63), horned 417 (258), western grebe 14,450 (5,817) and pied-billed 20 (9); double-crested 263 (226) and Brandt’s cormorant 59 (34) were also all time highs. Puddle ducks, especially mallard, [northern] pintail and American wigeon were generally down with the exception of the green-winged teal 1,916 (1,496). Barrow’s goldeneye 3,279 (2,335), harlequin 36 (25) and common merganser 590 (203) were highest counts ever for the diving ducks. Raptors were fairly consistent in numbers except for the largest number of red-tailed hawks 21 (9) and marsh hawks [northern harrier] 27 (10). Twelve species of shorebirds were recorded: black-bellied plover 111 (53) was an all time high, and lesser yellowlegs was a new species for our area. The spotted sandpiper seen on the log booms off the North Arm jetty, was a second count record. Bonaparte’s gull, 361, was the highest since 1956 (380). The northwestern crow 2,047 (1,452) was the highest ever. Other highs include black-capped chickadee 828 (684), chestnut-backed chickadee 311 (217), common bushtit 97 (42), brown creeper 24 (15), Bewick’s wren 35 (27), northern shrike 18 (12), and white-crowned sparrow 210 (156). Varied thrush 23 (53) was the lowest recorded in ten years, and the [European] starling count was down by about 40,000 over last year. Many of the birds are now roosting near the penitentiary in New Westminister. Five species were new for the Vancouver Count bringing the total since 1954 to 173. The lesser yellowlegs has been mentioned. Madelon Schouten’s group carefully observed a Franklin’s gull in Area K, while they were counting starlings at the Alberta Wheat Pool. This sighting was confirmed by the compiler the following day. American bitterns and mountain chickadees were reported independently by two parties and have been included in the list. Allen Poynter gave his wife [Helen] a verbal field description of the immature loggerhead shrike during the Count and has sent the description to the compiler. As a result it is included in the Count – the description will be sent to New York with the record. Our birders could expect anything on Count day – a free flying mute swan (Stanley Park), or an African shelduck (North Vancouver). Five species reported during the Count period (Dec. 20 – Jan. 4) but not on Count day were gyrfalcon, pine grosbeak, tree, Harris’s and Lincoln’s sparrows. Some birds have been deleted from the area lists and in some cases total numbers of individuals recorded have been reduced. For example, many of the very large flocks of starling reported on Lulu Island would also be counted at the evening roosts. To avoid duplication it was necessary to ‘balance’ the estimates. Also some birds of prey may have passed from one area to another. After these movements were closely examined, some counts were slightly reduced. The peregrine falcon that was report in Stanley Park was deleted from the list because it may have been the same bird seen earlier flying over the water toward the Park. The compiler feels that birds that are difficult to identify or are easily confused with other species, as well as rarities or new birds for the Count area, should be confirmed if possible, by a back-up party the following day, or a written description should be included with the day’s report before they can be accepted. It is better to have fewer species but have good ones. Next year we will have to try to get more watchers in the field, than species seen! R. Wayne Campbell Burnaby Lake Wildlife – Habitat or Epitaph? 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