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Introduction
In previous autumns I had noticed fairly large numbers of Meadow Pipits flying over the garden. In 1996 I decided to keep daily records of the numbers involved, as well as direction of flight, flock size, daily timing and weather conditions.My field of view spanned a corridor of ‘air-space’, running north/south, of approximate width 400 M. I had an indoor and an outdoor watch point. I do not consider that there was a great difference in my ability to detect Meadow Pipits between the two situations. Calls were easier to pick up outside, but on the other hand the greater comfort of the indoor situation made for easier scanning of the sky.
Observations were made every day during the migration period, starting at around sunrise on most days and continuing while Meadow Pipits were passing overhead.
Results
A total of 1,511 passed overhead between 7 Sept and 8 Nov. A pronounced peak occurred between 26 Sept and 2 Oct when 70% of the Meadow Pipits flew over. The largest daily total was 481 on 1 Oct, followed by 220 on 30 Sept and 180 on 28 Sept.
Direction
South was by far the most common direction of flight. 84% flew south followed by 9% south-east and 2% south-west. Less than 1% flew in each of the other directions. This pattern was more or less constant throughout the period except for the first half of September. During the period 7 Sept to 16 Sept, 55% flew east and 20% southSize of party
In October (this data was only obtained for Oct), 40% of the parties/singletons that flew over comprised one Meadow Pipit. The mean number of Meadow Pipits per party was 2.7. The three largest parties (comprising 22, 17 & 11 respectively) all flew over on the day with the largest passage, i.e. 1 Oct.
Daily timing
The first Meadow Pipits were usually noted shortly after sunrise, the largest numbers typically occurring about an hour later. The time of peak passage was however variable, for example on 27 Sept it occurred at around 10.00 a.m., whereas on the next day it was at around 8.30 a.m. Very few flew over after midday (excepting 1 Oct), the latest being 5.55 p.m.The length of time during which passage occurred was, more or less, proportional to the number of Meadow Pipits on a given day. By far the most protracted passage occurred on the day with by far the most pipits i.e. 1 Oct
Weather conditions
Wind strength This was the factor which best correlated with Meadow Pipit numbers. There was a sudden drop-off in numbers once wind speed went above 4 on the Beaufort Scale (‘light breeze’). On days with wind strength 4 or above there was an average of 0.4 Meadow Pipits, whereas on days with strength less than 4 the average was 23. This was well illustrated on 29 Sept, a day with strong wind and no pipits, which was sandwiched between two days with light winds and 180 & 230 pipits respectively.Wind direction This factor also correlated well with pipit numbers. Any conclusions here will be based, however, on very limited data. For example there was a north, north-east and south-east wind on only two mornings each. Mornings with north and north-west winds had the largest average numbers. The average numbers of Meadow Pipits on days with given wind directions were as follows: N 134, NW 80, W 31, NE 18, SW 7, S 5, E 4, SE 3.
Cloud cover On cloudless mornings fewer Meadow Pipits tended to be recorded (average 7) than on cloudy mornings (average 30). This may have been because fewer were flying on those mornings it also possible though, that they were flying higher and so went unrecorded.
Precipitation Rain occurred on only 5 mornings (and only light drizzle on 4 of those) when the average was 20, compared to 25 on dry mornings. Again this data is very limited.
Associated species
On 3 occasions single Pied Wagtails were seen flying with Meadow Pipits. This was the only species which showed a direct association.Discussion
1,511 Meadow Pipits was more than expected. In 1995 the number recorded was 663 when, an admittedly, less systematic count was carried out. There were however, several reports from Cheshire and elsewhere of diurnal migration being good in 1996, particularly so for Meadow Pipits.How many went unrecorded? Pipits would not have been recorded if: a) they flew over before or after recording was being carried out, b) they were flying too high to be seen or heard, c) they could have been recorded but were simply missed. All three factors are likely, to a greater or lesser extent, to have been at play. A very rough guess then, would be that a half of those which flew over were recorded.
Migrants are believed to (amongst other things) use leading lines and landmarks to navigate. This location appears not to have any such characteristics, which would concentrate overflying Meadow Pipits. However, the numbers recorded compare well with those at traditional ‘migration watch-points’. Two of the possible interpretations this suggests are: a) there could, in fact, be some subtle factor which makes this location favourable, or b) these numbers are nothing special and could be encountered ‘anywhere’.
If (and it’s a big if) we assume b) to be the case then these figures could be extrapolated for the whole of non-costal Cheshire, given my field of view and the breadth of the county. This is of course, highly speculative, but would yield a figure with order of magnitude 100,000.
"Birds in a Cheshire Garden"