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Frequently Asked Questions Random sites. Why do I have to survey a randomly selected site? BBS sites are randomly picked by computer and not selected by the BBS observer to ensure that the majority of habitat types in the UK are surveyed. It is vitally important that we survey less popular urban and upland sites and squares that contain few bird species, so that we obtain a representative sample of the bird numbers in the UK. Survey sites chosen by the observer tend to be ones that are best for the birds, such as nature reserves. Bird populations in these 'hot-spot' sites tend to fare better than those in the wider countryside and are therefore, not representative. However, from the observers’ point-of-view, the random site-selection of the BBS will take you to new parts of the countryside that you would not have normally visited. Most BBS squares will normally hold a wide diversity of species; for instance, we have an observer who regularly records more than 60 species from an inland square in the Kennet Valley in Berkshire. Access permission. How do I get access to private land that my transect route crosses? Most BBS transect routes run along public footpaths, tracks and minor roads and therefore, should not require any access permission. However, you may need to gain access to private land, and the most effective way of doing this is to visit your square and ask the landowner in person. In the vast majority of instances, landowners are happy to allow access across their land for the purpose of a bird survey. A letter of reference can be provided from your RO or the National Organiser, if needed. Refusal of access is relatively rare, but if it does occur, you must not continue your survey across that land. It is vital that we maintain good relations with landowners, for without their co-operation, the survey could not operate. Habitat change. Should I continue to survey my square if the habitat has changed out of all recognition? Yes, even if the habitat in your square has changed drastically from the previous year, it is vitally important that you continue to survey your square, so that we can monitor any changes in bird numbers that might have been caused by the habitat changes. Examples of dramatic habitat changes include the clear felling of woodland, construction of housing estates on open-land and the opening up of new quarries. Transect route change. Can I change my transect route? No, please do not change your transect route unless it is absolutely necessary. To enable us to produce accurate population trends, we must conduct our bird counts along the same routes in the same squares, year after year. Altering your survey route will alter the list of species and the numbers of each species you will record. However, it may be necessary to change your route permanently if the old route becomes dangerous to follow, or access has been refused to part of it for the foreseeable future. The new route should follow the old one as close as possible. Route outside my square. Is it okay for my transect route to go outside my square? Yes, small deviations into adjacent squares are perfectly acceptable if this is the only route you can take. In an ideal world, your transect route should follow the 'ideal route' across your square, but in most cases, access will prevented by physical barriers such as roads, rivers, hedgerows, walls and buildings. Time of year. At what time of year should I undertake my survey? In lowland Britain, the first bird-count visit should ideally be undertaken between early April and mid-May and the second visit between mid-May and the end of June. In upland areas and in Scotland and Northern Ireland, visits can be carried out a little later, but the second bird count should not be done any later than mid-July. Visits are undertaken during this time period, firstly to coincide with the peak singing periods for most resident and migrant bird species and secondly to reduce the number of unidentified juveniles recorded. It is very important that you are consistent and therefore, survey your square on roughly the same dates every year. However, if you find that it is impossible for you to do this in one year, it is better to make a late visit, rather than miss it out altogether. Time of day. At what time of day should I undertake my survey? The ideal time of day to survey your square to count birds in the breeding season is roughly one hour after sunrise until mid-morning (10-11am). This generally means starting your BBS survey at around 6-7am and ideally no later than 9am. Birds are generally most active at this time of day and most inactive in the early afternoon. However, if it takes you several hours to reach your square, and this can be the case in remote upland areas, we understand that you may have to survey your site in the afternoon. Again an afternoon visit is better than no visit, but most importantly, try to be consistent year after year. Weather. Should I undertake my survey on windy or rainy days? No, not unless it is absolutely necessary because bird song and activity is very much reduced on wet or very windy days. However, there are many parts of the country, particularly in the west and in upland areas, where these less than ideal weather conditions are the norm. Again, it is better to undertake the survey in less than ideal weather conditions than not to do it at all. It is also worth remembering that bird song can be quite intense after rain showers, and that birds will stop singing earlier in the day on very fine days, particularly if there have previously been several days of good weather. Colony counts. Do I need to record the same birds on my transect counts, if I am including them in my colony count? Yes, please write the number of adults you see, as well as the number of active nests counted at a colony. For example, if you record 20 active Rook nests on your colony count and you can see 35 adult birds on your line-transect count, enter 20 in the number of active nests and 35 in the relevant distance bands on your transect section counts. Aerial hunters and songsters; in which distance band do I record them? Hovering Kestrels and birds in song-flight, such as Skylark, Greenfinch, Sedge Warbler and Whitethroat should be recorded in the relevant distance bands. The correct distance band is determined by estimating the length of a line that runs at a right angle from your transect route to a point directly below where the bird is displaying or hunting. Swifts, swallows and martins should only be recorded in a distance band if they are seen to land or fly into a nest site, such as a barn or the eve of a roof. Habitat priority. I have three habitat types in my 200m section; which two do I choose? Firstly, the order in which the habitat types are entered, does not matter (i.e. the First Habitat and Second Habitat on the green Habitat Recording Form). However, if you have three distinct habitats within your 200m transect section, you will have to choose two of them. Select the habitats to include, in terms of the number of birds they are contributing to the survey and their physical size within the 200x50m rectangular habitat recording area. |
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