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Methods

Much of the methodology that follows is adapted from a variety of sources including “A Land Manager’s Guide to Point Counts of Birds in the Southeast” (Hamel et al, 1996) and Bird Census Techniques (Bibby et al, 2000), as well as Distance Software User’s Guide (Version 4.1, 2003). You may use either the bull’s eye form or spreadsheet format data sheet for point counts. You should use the spreadsheet version for line transect counts. The following details cover the lines of information on each form.

IBA: Please write the name of the IBA as it appears on our web page at www.ncaudubon.org.

Road or Trail name: Please list the road name or number on which your point occurs or on which your line transect lies. Name of trail is fine for line transects, or waterway name if canoeing or floating for a line transect.

Point Number: Each points will be assigned a number and a latitude and longitude will be determined for each point (Curtis will be happy to help with this part of the process. Please contact him via email at csmalling@audubon.org).

Selecting Point Counts

We usually try to set a point based on three criteria. These are access, habitat type, and density in the IBA.

Access – make the points accessible to observers including near or adjacent to tertiary roads or trials and if on private or public property, get permission from the property owners. Road side points can be conducted within DOT right of ways.

Habitat type – in general, try to select points in proportion to available habitat. For example, if 80% of the area is mixed hardwood forest, 80% of counts should be in that habitat and so on. Exceptions might be a single habitat that is less than 1% of the landscape but may have differing species. An example of this might be a bog in a large forested tract.

Density – one of the biggest questions to answer is how many points should we establish? Without spending a lot of time on the statistical reasoning for selecting points, we have chosen a target of 1 point per 4 square kilometers for IBAs over about 10,000 hectares. Smaller IBA’s can have a higher point count density, maybe as low as 1 per square kilometer. For an IBA like our Jordan Reservoir IBA, for example, that would be about 75 points. A small IBA like Pilot Mountain might only be 10 points. Staff will help you determine the number of points for your IBA.

Selecting Line Transects
Transects can be along established roads, trails, or watercourses. They may also be new routes away from these features as well. The most important points to remember with transects is that the same features as above apply. Access is important, transects should be representative of the available habitats, and make sure that enough transects are selected to adequately cover the IBA. Again staff will assist you in picking your transects.

Time of Counts

All breeding season counts, either point or transect, should be completed from sunrise to 11:00 am and from May 10th to June 30th. Migration or winter counts may be conducted at any time, just be sure to log start times in military time (ex. 6 p.m. is 1800)

How Long Do I Count?

Point Counts: On your data sheets, please denote three time periods. These are 3,5, and 10 minute counts. We denote these periods to allow comparison to other studies. Studies like the breeding bird survey use a three minute count, some land manager’s use 5 minute and most researchers use a 10 minute count. This can be delineated in several ways. On a bull’s eye form, three colors of ink works very well. On the data entry form, a simple line after the last bird counted in each period is sufficient. Make sure to only count each bird only once!

Line Transects: No set time duration limit, but log start and stop time.

Skies: Please note sky condition using standard descriptions. Those would be clear, cloudy, partly cloudy. Counts should not be conducted when it is raining or foggy.

Wind: Please use the Beaufort scale for your wind measurements. Acceptable levels are from 0-5 with the following subjective criteria:

Counts should not be conducted with winds higher than these levels.

Temp: For point counts log temperature at beginning of count. For line transects log temperature range from start to end.

Line transect distance: It is important for line transect counts that the total distance traveled be logged. This can be the trail length or watercourse mileage traveled. The more accurate this number is the more accurate our counts will be.

Species Alpha:

A list of standard abbreviations of bird species names is attached. Your use of these will greatly speed your use of the forms. Make sure that you are familiar with the common ones in your area. A note about ones you do not know while conducting your counts – use whatever short hand you want, just make sure that you check and correct those abbreviations at the end of the day. These abbreviations or alpha codes are the ones used by banders at their banding stations.

Distance measurement:

Please enter the distance to each bird seen or heard the first (and only the first) time you saw or heard it. Place the number of each species seen in each appropriate distance band.

Why Do I Measure Distance?

In general terms, a point count or line transect is a way to quantify the birds we see or hear in an area. All birds are not created equal however and some, like a Northern Cardinal, can be seen and heard easier than say a Golden-crowned Kinglet. By taking a distance measurement, we can begin to adjust for these different detectabilities. It makes sense that a bird with a quiet song and that is cryptically colored would b detected more often closer to the observer than a loud, big, and colorful bird. Simple distance measurements help us adjust for that. In both Point counts and line transects, you will be asked to estimate the distance to the bird you see or hear. To make it easier, we have divided the area you are surveying into distance bands. These bands (<25m, 25-50 m, and >50 m) will allow us to generate detection probabilities for the species you see and hear. You don’t have to do that as the observer. All you have to do is estimate which distance band the bird is in.

And it is not as hard as it sounds. Most of us have ways to estimate this that we use every day. Measure some common distances around your house and yard to give you a well defined distance that you see everyday. Maybe it is 50 m to your mailbox, or maybe your house is 25 m long. Measure some of those distances to begin to think about those distances. Another help is to pace one of those bands at your point count sites. You can establish your point center 25 from the edge of the road or trail or creek. This gives you a readily available measuring stick to gauge the birds you see during your point. The more you practice the easier it will be. And again, remembering one of the reasons we count birds is for presence and absence, so if you find distance measurement impossible, don’t do it. Your presence or absence lists will help us as well.

Line transects also use these distance bands. The birds are logged using their perpendicular distance from the transect. So if you see a bird fly up from the path in front of you, the distance is zero, or <25m. If it is singing in a bush 100 yards away from the transect it is in the >50 band.

Flyovers: Often during counts, birds fly over the point count circle or transect without taking off from within the area or landing in it. These birds are counted as flyovers and are listed in the flyovers column with no attempt at a distance measurement.

Nesting: This column is a simple way to note definite evidence of nesting (nest building, adult on nest, feeding juveniles, carrying fecal sacks, etc.). This data is shared with the NC Museum of Natural Sciences Breeding Bird Atlas project.

Comments: Use this area to note any special circumstances that might be of interest or impact the count. Some examples might be a predator in the area (dog, cat, fox) or unusual noises that hinder the count (loud truck, plane, or like last year in Wilkes County, 13 year Cicadas!!)

You may use either the bull’s eye form or spreadsheet form for point counts. Both are included because some people find it easier to keep track of birds on a bull’s eye form than on a linear form. It is important to try not to double count birds and the graphic layout of a bull’s eye sheet may help you with that. It is your choice. It is helpful for us when we enter the data if you have already transcribed the bull’s eye form to the spreadsheet version, but that is not required. Do whichever you are comfortable with because again, it is more important to get your data to us than worry about which form you use.

Thank you for your assistance in this very important process. Any data you can provide helps us learn more our Important Bird Areas. If you have questions or would like to schedule a training session in person with a staff member, please contact Curtis Smalling at csmalling@audubon.org or at 828-265-0198.

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