Sandra is a local photographer, naturalist and an active member of the Friends of Sam Smith Park steering committee.
As of the posting of this article, there are seven grebe pairs in the bay sitting on eggs - six on provided platforms and one on a rock outcrop.
“In order to see birds, it is necessary to become part of the silence”. Robert Lynd
The winter Olympic Games are long over, and soon it will
be time for those of the summer to begin. Although the “human” games happen
every four years, I think in terms of a different sort of Olympiad—the one that
unfolds with each successful return migration and nesting cycle.
Surviving on the wintering grounds, completing the long
flight northward, seeking a mate, locating and defending a nesting territory,
building a nest, mating, laying eggs, protecting, feeding and raising the young--all
in such a short period of time, are truly feats of Olympian
proportion. Human
athletes train for a scant number of years. Birds train for their entire lives.
PAIR BONDING |
In spring, soon after the ice recedes from Ontario’s lakes
and ponds, the plaintive wail of the Red-necked Grebe shatters the winter’s
silence. For the past few years, however, the shoreline of Lake Ontario in the
GTA and the marina at Colonel Samuel Smith Park have served as wintering
locations for some of these magnificent birds. Although its sound may not be as
musical or as lilting as that of the White-throated or Song Sparrow, it
announces that a new season has begun with grand changes in the offing.
Description,
Distribution and Range
Shedding their subtle gray feathers of winter, the
Red-necked Grebes that return to Ontario in March are clad in avian finery.
With their chestnut necks, distinctive large white cheek patches, natty jet black
crowns, dark gray head and long black bills that are yellow at the base, the
birds are a sight to behold. They are a medium-sized grebe with a length of
43-56cm, a wingspan of 61-88cm with weight averaging 800-1600g. The sexes are
similar in colouration, although the male tends to be larger than the female.
Although Red-necked Grebes are listed as one of the most
common diving birds found on large numbers of lakes in western Canada, their
presence in our area has most often been associated with migration alone. The
Canadian Atlas of Bird Banding describes their breeding range in Ontario to be
“from Lake Superior westward...” Such statistical data will most certainly need
updating thanks to our resident wintering and breeding population in Colonel
Sam Park. It is hoped that the park’s recent designation as an Environmentally
Significant Area (ESA) will provide the Grebes with added protection.
Courtship
Red-necked Grebes commonly form breeding pairs while still
on the wintering grounds and they tend to be monogamous during the breeding
season that lasts from May to
September. Sexual maturity occurs at 1-2 years.
COURTSHIP "GIFTS" |
The courtship period is noisy and active and may become
highly aggressive, especially when other Red-Necked Grebes dare venture too
near. Although the birds tend to be largely silent during the non-breeding
period, such is not the case when pair bonds are being established. Whether
singly or as part of a duet, the birds commonly enter into bouts of loud wailing
during their highly ritualized courtship and territorial defence displays. At times they appear to run on the surface of
the water as they rush closer together in an upright position and present each
other with “gifts” of green vegetation. Thrashing of wings, hunching of bodies
and pointing of bills upward are parts of the “arsenal” employed when
interlopers begin to encroach.
Habitat and Nesting
In spring, Red-necked Grebes seek out marshy ponds and
shallow bodies of fresh water. Although the male initiates site selection, both
birds are involved with nest building. Aquatic (emergent) vegetation forms the
primary building material for nests that, in the wild, are built atop a “platform”
of floating plant material. Nests are
often secured to vegetation at the bottom of a pond. (FOSS offers a very special thank
you to Mr. Joe Calico in appreciation for successfully designing and building
platforms for the Red-necked Grebes that nest in the Colonel
Sam Smith Marina). The upper layer of the nest consists of sticks and
bulrushes. It is not uncommon to observe a nest entirely surrounded by open
water.
DEFENDING THE NEST |
A clutch of 1-9 light blue eggs is laid in a depression
formed in the middle of the nesting mound. Both parents share incubation duties
lasting 21-33 days. Immediately upon hatching (asynchronous), the downy and
precocial chicks climb onto a parent’s back where they will spend most of the next
10-17 days. At times, the brood may be split between the parents in order to
spread the demand for feeding equally between the adult birds.
The parents continue to feed the young for approximately
50 days. Fledging occurs after
50-70 days. Normally Red-necked Grebes raise a
single brood, although re-nesting after a clutch has been lost or the
incubation of a second clutch is not uncommon.
TURNING THE EGGS |
Diet
The grebe’s diet is varied and includes small fish, minnows,
sculpins, crustaceans, tadpoles, aquatic insects, crayfish and some vegetation.
They are also known to catch low flying insects out of the air.
Adult Red-necked Grebes ingest large amounts of their own
feathers, while feathers of parent birds are found in the stomachs of
their
small chicks. It is speculated that
these wads of feathers act as a sort of padding that protects their stomachs
from sharp fish bones. They may also retard the digestion process allowing
bones to dissolve and not pass into the intestine.
FEEDING THE CHICKS |
Threats
and Status in Ontario
Red-necked Grebe populations are relatively healthy and
stable in Ontario. They suffer predation from foxes, raccoons, mink, muskrat, pike,
Bald Eagles, gulls, ravens, crows and even American Coots. They are susceptible
to disturbance from farming, fracking, road building and general human
interference with the wetlands and lakes they require for feeding and nesting. Contaminants
such as heavy metals and organochlorines that accumulate in the tissues of
their prey are suspected for causing thinning of egg shells
and egg sterility.
Boat traffic near nesting areas should be minimized to prevent disturbance to
the birds and their nests.
RED NECKED GREBE FAMILY PORTRAIT |
Conclusion
One of the first books I truly called my own was Ernest
Thompson Seton’s “Wild Animals I Have Known”. I treasured my old dog-eared copy
and, to this day, have not forgotten the wonderful word portraits he painted. His
tales are etched in my mind as though it were yesterday. For those who have not
yet read this classic book, I urge you to do so as it recalls memories of a less
degraded and threatened natural world. This “portrait” of the Red-necked Grebe
is dedicated to such memories.
Resources
http://www.birdsontario.org/atlas/atlasbook.jsp?pg=043
Red-necked Grebes—Atlas of Breeding Birds of Ontario
http://www.ofnc.ca/birding/bbanestdates.html
Migration and Nesting Dates for Ontario Bird Species
https://www.allaboutbirds.org/guide/Red-necked_Grebe/id The
Cornell Lab of Ornithology—All About Birds
http://www.ec.gc.ca/aobc-cabb/index.aspx?lang=en&nav=bird_oiseaux&aou=2
Canadian Atlas of Bird Banding-Environment Canada
http://www.registrelep-sararegistry.gc.ca/species/speciesDetails_e.cfm?sid=322 Species at Risk Public Registry
http://www.gutenberg.org/files/3031/3031-h/3031-h.htm
(Project Gutenberg free downloadable copy of Wild Animals I Have Known by
Ernest Thompson Seton).
Erlich, Paul R., Dobkin, David S. and Wheye, Darryl, 1988,
The Birder’s Handbook: A Field Guide to the Natural History of North American
Birds, Simon and Schuster, New York, N.Y.
Godfrey, W. Earl, 1990 Rev. ed., The Birds of Canada,
National Museum of Natural Sciences, National Museums of Canada, Ottawa.
*This
article was first published in Nature Alberta Magazine in 2014. It has been
edited to include Ontario references. All photographs were taken at Colonel
Samuel Smith Park or at Humber Bay East Park.
3 comments:
Do you mind if I quote a few of your posts as long as I provide
credit and sources back to your weblog? My blog is in the exact same area of
interest as yours and my visitors would really benefit from a lot of the information you provide here.
Please let me know if this okay with you. Thanks a lot!
Hi there
Please contact us directly at friendsofsamsmithpark@gmail.com
Your comment was signed as "Anonymous" and it is not possible to respond to you directly.
Hello would you mind sharing which blog platform you're
working with? I'm going to start my own blog soon but I'm having a hard time making a decision between BlogEngine/Wordpress/B2evolution and Drupal.
The reason I ask is because your layout seems different then most blogs and
I'm looking for something completely unique. P.S Apologies for being off-topic but
I had to ask!
Post a Comment