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Index of Subjects Hi Ian and others, Just to follow up what you've noted, going by data presented on CWS's breeding bird web page, the breeding bird survey for the last 10 years for House Sparrows in Nova Scotia indicates a mean annual percent decline of 12.5% and for the last 20 years a decline of 7.8%. Both have a P < 0.05. So while the 40 year trend doesn't quite measure up, the last twenty certainly do. Of course the breeding bird survey simply reflects what is happening along BBS routes and it doesn't appear that any routes go through urban centers in Nova Scotia. Therefore if there is a resurgence in the urban population of Metro Halifax-Dartmouth House Sparrow populations I wouldn't expect it to be noted by this method. The Halifax-Dartmouth Christmas bird count data when taken by itself, apart from the rest of the province's CBC data, certainly presents an interesting picture. At its inception in the early 90's, the Halifax-Dartmouth count had a lower bird per party hour than it did last year (~2 versus ~4). However in the late 90s the number was in the 8.5-9.5 range and it has dropped to the current level since then. Last year's rise from the previous year (from ~2 to ~4) hopefully reflects the start of a recovery but it may also be a small peak in an otherwise steadily declining population. That is, of course, the point behind long term projects such as Christmas bird counts and breeding bird censuses. To determine the long term trends hidden in the annual variation. I looked at the last 30 years of the Halifax (east) and Halifax (west) Christmas bird counts to see what that showed and they are consistent with my original email. In the early 1960s 30-35 birds per party hour were being seen. By the end of the counts, when the Halifax-Dartmouth CBC replaced the two, separate counts, the numbers were down to about 2 per party hour. To summarize, the original two Halifax CBCs' data indicate a very large decline from the early 1960's (30-35 birds per party hour) to the early 1990s. At this point a new, Halifax-Dartmouth CBC replaced the two counts. The data shows an increase in numbers of House Sparrows being seen from ~2 to a high of 8.5-9.5 birds per party hours over the next 5 or so years and then a decline over the last 15 years to the present range of 2-4. All the best, Lance
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