 wetlandsa publication of Sungei Buloh Wetland Reserve |
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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 |
 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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