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Vol 13 No 3
Is that a crocodile or a monitor lizard?
Special projects to Understand Nature (SUN Club)
Dragonflies and Damselflies of Sungei
Buloh
The Kranji Countryside: Singapore's
very own countryside
Migration monitoring at Prince Edward Point BIrd Observatory, Ontario, Canada
Selai Endau Rompin
Johor National Park
A feathered friend from Thailand
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Migration Monitoring
at Prince Edward Point Bird
Observatory, Ontario Canada
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Ray Knock
Businessman, SBWR
Volunteer
Bird Ringer based in the United Kingdom
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 Relaxing afternoon: Cold beer in hand and binoculars slung
around my neck. I’m at the shore of Lake
Ontario watching Ospreys (Pandion haliaetus)
wing their way over the lake, and Ring-billed Gulls (Larus
delawarensis) fly round and land to pick food
from the beach, while Turkey Vultures (Cathartes
aura) soar, wings spread out, on the thermals. Ahh,
Prince Edward Point is a great place for a birding experience of a lifetime.
Prince Edward Point Bird Observatory is situated in the Prince Edward county
of Ontario, 200kms north-east from the city of Toronto. The county includes
an island that sits in Lake Ontario, one of the five great lakes of North
America. The Observatory is located in a national wildlife area at the most
easterly point of the island and is set among scrub and mature trees complete
with cheeky Chipmunks and Red Squirrels that scurry around all day. The
island is a focal point for migrating passerines and raptors, so in 1995 the
Observatory was established to help monitor the spring and autumn migration
of birds. In 1999 the observatory became part of the Canadian migration
monitoring network that comprises 22 observatories and monitoring stations in
Canada. Information from the ringing studies and bird counts is collated by
Bird Studies Canada where analysis of the information helps towards the
understanding of the status of birds in the Americas. Much of northern
Canada, particularly the expansive boreal forests, is inaccessible.
Consequently, breeding birds that nest in these forests during the summer are
not well studied. However, because the migration monitoring network uses
standardised ringing and counting methods, the population trends of these
breeding birds in the northern forests can still be determined.
I visited the Observatory in September 2005, to participate in the ringing
programme that monitors the autumn migration. It was also my first visit to
North America so all the bird species I encountered were new to me. To
identify, age and sex a new array of birds was both daunting and exciting,
particularly so, as between 80 & 90 different species are regularly
caught and ringed at the Observatory.
The most colourful group of birds I encountered were the warblers with over
20 species caught. The commonest species are the Yellowrumped
or Myrtle Warbler (Dendronica coronata) and the Magnolia Warbler (Dendronica magnolia). Both species can
winter as far south as Mexico and Central America. Apart from the common species,
I was lucky too to ring an Orange-crowned Warbler (Vermivora
celata) and a Tennessee Warbler (Vermivora pergrina)
both of which occur as rare migrants.
There was a diverse range of size in the birds that were caught. The very small
Kinglets, Golden-crowned (Regulus satrapa) and Ruby-crowned (Regulus
calendula) were only 8 to 11cms long and weigh 6 to 9 grams. It is not
unusual to catch up to a thousand individuals of each of these species during
the autumn. At the other end of the size scale was the Sharp-shinned Hawk (Accipiter
striatus). Although considered small for a
hawk, they still weighed in at over 200 grams and had wingspans of over 56cm.
These hawks hunt in the taller trees and the Observatory had special large
mesh nets that could be raised into the canopy using a pulley system and then
lowered again to enable the extraction of the trapped hawk. The hawks had
bright colourful evillooking eyes and I had to be
careful to keep uncovered flesh (like fingers!) away from their needle sharp
talons!
Slightly smaller than the hawk is the Blue Jay (Cyanocitta
cristata), an abundant bird of North America,
with stunning blue and white plumage. When the peak passage of the jay takes
place, it is not unusual to count up to 5,000 jays per hour passing over the
Observatory. This fact impressed me, as our European Jay (Garrulus
glandarius) is a secretive bird and normally I
am lucky to see one at a time!
 Not withstanding this fact, I consider the most amazing bird to be the
Ruby-throated Hummingbird (Archilochus colubris).
It is the only hummingbird that breeds in eastern North America and it is a
really tiny bird, weighing in at just 4 grams! These birds are caught in
special hummingbird traps and as the technique of ringing them is also very
different from the usual assortment of birds, a special license is required
for one to ring them. I was fortunate that the warden of the Observatory was
licensed and allowed me to ring one under his expert tuition. The “rings’’
are supplied on a flat sheet of aluminum with the
numbers photo-etched on, and the ringer has to cut out the ring and form it
himself using a small jig. The fitting of the ring is done under a large
magnifying lens and closed with a special pair of pliers - a really delicate
operation I should say. Holding the tiny bird in my hand, the realization
that these birds actually migrate to Mexico and Central America, crossing the
Gulf of Mexico in one non-stop flight is nothing short of amazing!
During major movements, bird numbers caught can be quite large. On one Sunday
we caught and ringed nearly 700 birds! It was fortunate that we had two other
local ringers join us for the day. As we worked through ringing the many
warbler and thrush species we noted the more unusual ones such as the
Rose-breasted Grosbeak (Pheucticus ludovicianus), Slate-coloured Junco (Junco hyemalis) and Yellow-bellied Sapsucker (Sphyrapicus varius)
that is actually a species of woodpecker. As it turned out, that day’s catch was a record in terms of bird numbers
ringed in a single day at the Observatory and we all had a nice celebration
with the wardens’ whisky!
Many birds are caught using mist nets but we also made use of a selection of
ground traps that are essentially baited wire mesh cages. These traps have
openings for the birds to enter easily but with no way of exiting on their
own. They are designed to catch finches and we managed to obtain the stunning
black and yellow plumaged American Goldfinch (Carduelis
tristis) and several species of sparrows. The
Swamp Sparrow (Melospiza Georgiana),
quite a scarce species, was one of five different species I ringed in Canada –
that made my day as I’ve been studying
sparrows, albeit of a different species in my home area in the United
Kingdom.
Towards the tail end of the autumn migration, one species that the
Observatory targets to trap is the Northern Saw-whet Owl (Aegolius
acadicus). In a good year, 700 to 800 of these
small owls are ringed when they migrate through the Observatory. The owls are
lured to the nets by repeatedly playing a tape recording of the bird’s call. Each night, we sat in the observatory and
listened to the owl’s call emanating from the
tape players. No luck though. The owls were late that year. The nightly
vigils however were not fruitless as two Whip-poor-wills (Caprimulgis
vociferous) that are a type of Nightjar, were netted. I was delighted to
be able to add this unusual species to my Canadian ringing list. Guess I will
just have to return to the Observatory for another attempt at the owls!
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