Ontario Breeding Bird Atlas, Region 24 (Ottawa)

Region 24 (Ottawa) Report for 2002

by Christine Hanrahan

Note: 2001 summary report still available

Introduction
If year one was a time for atlassers to acquaint themselves with the atlas process and become familiar with their territory (squares), year two has clearly been a time of serious data gathering. Almost every square reported big increases in numbers of species recorded. Many more point counts were done and some atlassers participated in the Atlas Nocturnal Owl Survey.

Most of you are familiar with the details of Region 24 but for the new folk, here is a quick overview. Our region, which contains 86 10 km X 10 km squares, extends roughly from Casselman in the east to Westmeath, in the west, south to Flower Station, Winchester and Finch, with the Ottawa River as our northern boundary. Along with the City of Ottawa, the area encompasses the towns of Arnprior, Renfrew, Pakenham, Almonte, Russell and Chesterville. Also included: the Larose and Marlborough Forests, White Lake and Richmond Fens, Gillies Grove, the Burnt Lands Alvar, Winchester and Moose Creek Bogs, Mud Lake and Mud Pond, the Innis Point Banding Station, Shirleys Bay… the list goes on. And let’s not forget the famous cornbelts in the east!

Of the 86 squares in our region, only one has not yet received any coverage, 18VR14, a sliver of land along the Ottawa River near Dunrobin. However, it now has a volunteer ready to go for next year.

Several of last year’s atlassers moved on to new ventures. We wish them well and thank them for their significant contributions to the atlas. At the same time we welcome all the new volunteers who have now brought the number of participants to 95 (up from 81 last year). We still have two natural history clubs taking part, the MacNamara Field Naturalists of Arnprior and the Mississippi Valley Field Naturalists of Carleton Place.

Forward to 2003!
Confirmations: The Atlas has set a goal of a 50% confirmation rate per square, a goal we’re trying hard to achieve. As many know, finding evidence of confirmed breeding is not always easy, but those atlassers who spent time in the field through July and early August generally had higher confirmation rates than others who stopped atlassing in June. However, birding at the right time is only part of the story, the other half is learning how to find solid breeding evidence, and of course plain old good luck plays a big part too! Watch for some tips on the local atlas web pages. In July we’ll hold a field workshop to provide some hands-on experience.

Night birds: Owls and crepuscular species are difficult to census, and in the next three years we plan to try varied approaches to help us attain a good level of coverage for this group of birds. Watch for nocturnal square bashes and possibly more owl prowls.

Breeding vs. migration dates: Please check out the Migration and Nest Dates posted on our local atlas web pages and become familiar with who does what when. You’ll be better able to determine whether the bird you just saw is still in migratory mode – or not. This is especially important for the uncommon to scarce breeders in our region. Warblers in particular can be problematical because they generally come through in mid-to-late May when many other species are on territory or have begun nesting and the tendency is to record species within this group as possible breeders if observed in late May. It is best to check the range of nesting and migration dates for each species and use that data along with your observations of what the bird is doing and then make a decision based on your best judgement. A Black-and-white Warbler, for example, carrying nesting material is certainly on territory, but the same species found in a mixed flock of warblers obviously feeding on the wing, so the speak, is best not recorded as a possible breeder. If in doubt, please contact me. If I can’t answer your question, I’ll put it to one of the other committee members.

New stuff: This year the folk at Atlas Central organized a couple of interesting projects. First was the Atlas Nocturnal Owl Survey (ongoing to 2005) complete with instruction manual and CD or cassettes, and second was a compilation of bird photos and bird songs (the Bluebird CD-ROM) which was made available free to any atlasser who wanted one. An update of the Bluebird CD-ROM may be in the works for 2003.

Watch for a more complete report in the OFNC publication, Trail & Landscape, in the new year.

Results for 2002

Breeding evidence has now been found for 177 species, with confirmed breeding for 139 species.

Numbers of species per square
In Table 2, you will find the total number of species recorded in each square. Based on our knowledge of the region and results from the last atlas, the local atlas committee has set a goal of at least 80 species per square east of Ottawa and at least 90 species west of the city. Quite obviously this is not a hard and fast rule, simply a general guideline. For example, some squares east of Ottawa have a significant diversity of birds and finding a 100 species or more is very probable while in others, getting 70 species will present a challenge. Furthermore, some squares have less than 50% of their land mass in Ontario; expectations for these 13 squares will be somewhat different.

Of the 85 squares that have so far been atlassed, 13 have recorded more than 100 species; the highest number recorded is 124 species in 18UR80. Twenty-four (24) squares have recorded between 80-99 species.

We’re aiming to have breeding confirmed for 50% of the birds found in each square. To date, only ten squares have reported 45 or more species with breeding confirmed. The highest total thus far is 72 species in 18VR30, followed closely by 70 species in 18VR52.

Highlights this year included several species not reported for the last atlas in this region: Black-crowned Night-heron (1 square), Black-backed Woodpecker (1 square), Tennessee Warbler (3 squares), and Le Conte’s Sparrow (1 square).

Found on the previous atlas but not reported during this atlas until 2002 were Least Bittern (four squares), Philadelphia Vireo (2 squares), Northern Parula Warbler (1 square), and Lincoln’s Sparrow (2 squares).

While Cape May Warblers were not recorded on the last atlas, they were found on 2 squares last year and on 5 more this year, although none were confirmed as breeding. Both the Tennessee and Cape May Warblers are essentially birds of northern coniferous forests. However, the last atlas saw scattered records for both species south of Algonquin Park and local Ottawa birders have generally anticipated a more southerly range expansion for them as nesting birds. It will be interesting to see what happens with these species in Region 24 over the next three years.

Other: Black-billed cuckoos were noticeably widespread ths year, recorded on 33 squares (44 squares cumulatively – 2001-02) although there were only a few with breeding confirmed. To anyone who noted the abundance of tent caterpillars, the ‘outbreak’ of black-billed cuckoos was no surprise, since the one follows the other, the caterpillars being a favoured food source which are fed in great quantities to young birds.

Evening Grosbeaks were also recorded widely in 2002 compared to the previous year. Like the crossbills, this is another species of irregular occurrence, found sporadically in some years, relatively common in others. This species was recorded on 33 squares, but only 6 had confirmed breeding records, all of these involving fledged young.

Acknowledgments
Thank You to every one who participated in the Breeding Bird Atlas this year. Thank you for spending so much time and effort surveying your squares, contributing casual observations, helping out fellow atlassers, doing point counts, taking part in owl surveys, sharing your sightings and your enthusiasm. Without your help we simply wouldn’t have an atlas.

As always heartfelt thanks to the local Atlas Committee: Mark Gawn, Paul Jones, and new member, Mick Panesar. They’re always ready with comments, suggestions, thoughts, plans for helping ensure that our region runs smoothly. Mark organizes our workshops (this year at Jack Pine Trail), and Paul is our front man, talking to other local natural history groups about the atlas.